tag:theconversation.com,2011:/africa/topics/engineering-824/articlesEngineering – The Conversation2024-03-28T18:54:32Ztag:theconversation.com,2011:article/2268342024-03-28T18:54:32Z2024-03-28T18:54:32ZAfter the Baltimore bridge collapse, we need clear-eyed assessments of the risks to key infrastructure<p>Catastrophic collapses of major bridges are thankfully rare. Notable examples in the last couple of decades include the failure of the <a href="https://www.dot.state.mn.us/i35wbridge/collapse.html">I35-W in Minneapolis in August 2007</a>, and the collapse of the <a href="https://theconversation.com/genoa-bridge-collapse-maintaining-these-%20structures-is-a-constant-battle-against-traffic-and-decay-101627">Morandi bridge in Genoa 11 years later</a>. When such events do occur, public attention is understandably focused on the nature of the collapse, which can extend over hundreds of metres in seconds, and its underlying causes. </p>
<p>Whether because of an extreme loading event or an accident, these supposedly rare events in the life of a bridge need to be assessed before they happen, and mitigation measures taken in accordance with the potential consequences. This type of analysis is known as a “risk-based consequence assessment”. The cost of taking additional measures in the near term can prevent major adverse consequences further down the road.</p>
<p>With many bridges being over 50 years old, we often hear that a bridge’s condition may have been compromised by deterioration and increased traffic loads – both in the size and frequency of vehicles. Also, older bridges were designed to standards that have been superseded by new knowledge and technology.</p>
<p>While these factors have helped convince some politicians to increase their infrastructure budgets, including through the <a href="https://www.whitehouse.gov/briefing-room/statements-%20releases/2021/11/06/fact-sheet-the-bipartisan-infrastructure-deal/">Bipartisan Infrastructure Deal</a> in the US, the tendency has been to focus on stronger, more resilient new structures and on higher maintenance for existing structures. Thus, it is easy for politicians to show the money spent has had a positive impact, because it results in an overall reduction in the number of structures classified as obsolete or deficient.</p>
<p>Given the enormous scale of the bridge maintenance problem – the American Road Transportation Builders Association has estimated that <a href="https://theconversation.com/disasters-like-bridge-collapses-put-%20transportation-agencies-emergency-plans-to-the-test-207779">one in three US bridges needs repair</a> – it makes sense to spread available funding widely. However, this approach can have serious shortcomings if it does not set clear priorities based on potential consequences from accidents and failures.</p>
<p>One of the two central pylons of the <a href="https://en.wikipedia.org/wiki/Francis_Scott_Key_Bridge_(Baltimore)">Francis Scott Key bridge</a> in Baltimore was rammed by a 300m-long container ship at around 1.30am on March 24, leading to progressive collapse of the bridge’s entire <a href="https://en.wikipedia.org/wiki/Truss_bridge">truss</a> within four seconds. </p>
<p>Although the 47-year-old bridge had been <a href="https://www.cbsnews.com/news/francis-scott-key-bridge-baltimore-condition-container-ship-what-we-know-how-collapse-happened/">found to be in a “fair” condition</a> during its most recent inspection in 2008, and was “fully up to code” according to Maryland’s governor after the collapse, experts agreed that a catastrophic collapse <a href="https://www.cbsnews.com/news/francis-scott-key-%20bridge-baltimore-condition-container-ship-what-we-know-how-collapse-happened/">was to be expected</a> given the magnitude of the ship’s impact. Construction workers were on the bridge at the time filling potholes, including the <a href="https://www.bbc.co.uk/news/world-us-canada-68673146">six people who died</a>.</p>
<h2>Direct and indirect consequences</h2>
<p>Bridge collapses due to vessel collisions have happened before and unfortunately will happen again. In a similar incident in 1980, <a href="https://www.structuremag.org/?p=20417">the Sunshine Skyway bridge in Tampa Bay</a>, also a steel truss structure, was hit by a barge, resulting in 35 casualties due to the collapse of over 1,300ft of its span. </p>
<p>Around the world, the American Association of State Highway and Transportation Officials has reported 31 major bridge collapses <a href="https://doi.org/10.1016/j.marstruc.2020.102840">due to vessel collisions</a> between 1960 and 2002, resulting in 342 deaths.</p>
<p>The destruction of the Francis Scott Key Bridge has cut off one of three transport links across the Patapsco river in the busy Baltimore port area. Given its importance as a transport hub, this will have major economic implications that could have been anticipated. </p>
<p>More than 30,000 vehicles that were using the Key Bridge daily now have to seek alternative routes. Significantly, the other two local crossings are via tunnels, which imposes limits on the type of traffic that can cross the river, because the transporting of hazardous materials through tunnels is prohibited.</p>
<p>Shipping traffic into and out of the Baltimore port has been suspended until further notice. Removal of the debris will be a complex operation, and work to ensure all vessel types can navigate the river safely will take time.
Further restrictions will need to be in place when the new bridge is constructed.</p>
<p>There are already signs that supply chains around the world are being affected by the bridge collapse, especially in the car and light truck sector as well as in farm and construction machinery. </p>
<p>The economic consequences of this catastrophic event will be substantial at both city and state level, with potentially wider ripple effects. Early estimates on liability insurance payouts suggest the total cost may <a href="https://www.ft.com/content/17cf3f2e-e64d-4666-b1c2-2723347c2ada">exceed US$1.5 billion (£1.2 billion)</a>. </p>
<p>Judging by what has happened after other bridge collapses, there could be negative impacts on jobs and the local economy: about 14,000 people work in the port itself, and another 140,000 are employed in related services. </p>
<p>Above all, six people lost their lives. But the human cost could have been much worse if the incident had taken place during rush hour. Had the impact occurred with a vessel carrying hazardous materials, the environmental costs could have been dramatic as well.</p>
<h2>What could have been done?</h2>
<p>Given what we know from previous incidents about the severity of ship-bridge collisions and major bridge collapses, decision-makers should have understood the critical importance of this bridge and the consequences of its destruction.</p>
<p>A number of mitigation options were available, including the installation of protection devices around the bridge supports (pylons) in the form of fenders or artificial islands, to deflect a ship or lessen the energy of a collision. </p>
<p>For bridges in general, there are measures that can help on the ship side too, such as requiring the use of tugboats or introducing stricter limits on speeds, depending on the type of cargo and vessel size. It is not clear, however, whether these would have made any difference in the case of the Baltimore bridge collapse.</p>
<p>Above all, by undertaking a risk-based consequence assessment every decade or so, authorities that are responsible for vital infrastructure can help visualise changing risks and prioritise their responses appropriately. In the case of river bridges, ever-increasing ship sizes, speedier turnaround times and higher cargo volumes have all increased the risks – and the costs of a catastrophic collision or collapse.</p><img src="https://counter.theconversation.com/content/226834/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Marios Chryssanthopoulos has received funding from UKRI, Network Rail, Highways Agency and the European Commission.</span></em></p>The collapse of the Francis Scott Key bridge is already affecting global supply chains.Marios Chryssanthopoulos, Professor of Structural Systems, University of SurreyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2267852024-03-28T10:23:50Z2024-03-28T10:23:50ZBaltimore Key Bridge: how a domino effect brought it down in seconds<p>The <a href="https://www.bbc.co.uk/news/live/world-us-canada-68663071">collapse of the Francis Scott Key Bridge</a> in Baltimore on 26 March was a shocking and tragic event. Six people remain unaccounted for in the disaster, which saw the world’s third largest continuous truss bridge fall into the Patapsco river.</p>
<p>The cause was Singapore-flagged container ship, the Dali, which veered off course, <a href="https://www.cbsnews.com/news/baltimore-bridge-collapse-ship-what-caused-crash-francis-scott-key-dali/">colliding with one of the bridge’s supports</a>, or piers. As the 300 metre-long vessel slammed into the structure, it triggered what’s known as a <a href="https://www.sciencedirect.com/science/article/pii/S2590123023002177">progressive collapse</a>, where a domino effect leads to the entire structure failing. The bridge, built more than 45 years ago, crashed down into the frigid water at 1:28am eastern standard time (5:28 UTC).</p>
<p>But how could one ship bring down this 366m (1,200 ft) structure within seconds of the collision? </p>
<p>A progressive collapse involves the failure of a single element, like the pier, and results in the sequential failure of other connected components. These can include the metallic truss and the bridge’s deck. This type of collapse can have catastrophic consequences in terms of the risk to human life, as well as to the economy of an area and the local environment. </p>
<p>Although it’s impossible to account for every scenario, bridges can be built with inherent features that enhance their resistance to progressive collapse. Typically, bridges can withstand some degree of damage to a pier or part of the superstructure. The bridge deck can even remain safe for vehicles depending on the circumstances.</p>
<p>However, in the case of the Baltimore bridge collapse, the metallic truss was designed <a href="https://www.washingtonpost.com/local/2024/03/26/francis-scott-key-bridge-history-baltimore/">as one continuous system</a>. The space between each support, or pier, is known as the truss span. The collapse of one of the piers effectively doubled the truss span to the next support. This dramatic increase in span exerted a much larger force on the remaining truss structure. </p>
<p>While continuous truss systems are favoured because they can redistribute weight in the event of damage, in this case, the remaining truss elements couldn’t withstand all that extra force after the pier failed. </p>
<p>This resulted in the complete collapse of the truss section above the damaged
pier. The collapse didn’t stop there, however. Due to the interconnected nature of the trusses, the remaining section was initially pulled upwards. The sudden release of this tension created a powerful dynamic effect, ultimately causing the entire bridge to collapse.</p>
<h2>Rare event</h2>
<p>It’s certainly not unknown for ships to strike bridge supports. On May 9, 1980, <a href="https://www.fox13news.com/news/sunshine-skyway-bridge-francis-scott-key-baltimore-tampa-st-pete-florida-pinellas-hillsborough-collapse-boat-freighter">a strikingly similar event</a> took place when a freighter <a href="https://eu.jacksonville.com/picture-gallery/news/state/2019/05/08/photos-sunshine-skyway-bridge-disaster/809810007/">collided with a support pier of the Sunshine Skyway Bridge</a> in Tampa Bay, Florida. As a result, the bridge failed over a similar distance as the Baltimore collapse.</p>
<p>But while bridge designers are acutely aware of the potential for collisions, these are – at the same time – rather rare events. The impact forces on a support pier are also highly variable. A higher speed or heavier ship will significantly increase the force on the pier. And higher vessel traffic in the water boosts the probability of a collision.</p>
<p>In addition, the current method used in the US for calculating the collision force of a ship is based on <a href="https://www.taylorfrancis.com/chapters/edit/10.1201/b15621-9/vessel-collision-design-bridges-michael-knott-zolan-prucz">research conducted between 1967 and 1976</a>. However, a different method would have been used for the Key Bridge, which opened in 1977. Needless to say, vessels as heavy and fast as the Dali were not a common sight in 1977. </p>
<p>In fact, the collision force under some scenarios is likely to be <a href="https://www.newcivilengineer.com/latest/baltimores-366m-span-steel-truss-bridge-collapses-after-being-struck-by-container-ship-26-03-2024/">well beyond the capacity of bridge piers to withstand</a>. This is why bridges have other systems of protection, such as dolphins – a group of pilings situated in the water near a pier, which serve to deflect a vessel or take the energy out of a collision.</p>
<p>There isn’t any information about the system that was installed when the Key Bridge opened in 1977. And some observers have questioned whether the <a href="https://www.nytimes.com/2024/03/26/us/baltimore-key-bridge-structure-support-pier.html">protective barriers around the Baltimore bridge were sufficient</a>.</p>
<p>Regular structural assessments and retrofits are crucial to ensure a bridge meets current safety standards. Concrete and steel, the primary materials in this bridge, are susceptible to deterioration from factors like corrosion and other environmental conditions. </p>
<p>In general, insufficient maintenance or inadequate retrofits can be contributing factors when bridges collapse. However, it must be said there is no evidence this was a factor in this case – and the Key Bridge <a href="https://web.archive.org/web/20240326081517/https://www.cnn.com/2024/03/26/us/baltimore-key-bridge-collapse-tuesday/index.html">was said to be “up to code”</a> when the disaster occurred. </p>
<p>There will be more detail to come on this dramatic and tragic event. And the findings will surely inform future approaches to the design and protection of bridges across busy waterways.</p><img src="https://counter.theconversation.com/content/226785/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Dr Mohamed Shaheen does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>We’ll need to learn the lessons from this disaster.Dr Mohamed Shaheen, Lecturer in Structural Engineering, Loughborough UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2267162024-03-27T03:59:18Z2024-03-27T03:59:18ZBaltimore bridge collapse: a bridge engineer explains what happened, and what needs to change<p>When the container ship MV Dali, 300 metres long and massing around 100,000 tonnes, lost power and slammed into one of the support piers of the <a href="https://en.wikipedia.org/wiki/Francis_Scott_Key_Bridge_(Baltimore)">Francis Scott Key Bridge</a> in Baltimore, the <a href="https://apnews.com/article/baltimore-bridge-collapse-53169b379820032f832de4016c655d1b">bridge collapsed in moments</a>. Six people are presumed dead, several others injured, and the city and region are expecting a months-long logistical nightmare in the absence of a crucial transport link.</p>
<p>It was a shocking event, not only for the public but for bridge engineers like me. We work very hard to ensure bridges are safe, and overall the probability of being injured or worse in a bridge collapse remains <a href="https://www.icevirtuallibrary.com/doi/10.1680/feng.13.00021">even lower</a> than the chance of being struck by lightning.</p>
<p>However, the images from Baltimore are a reminder that safety can’t be taken for granted. We need to remain vigilant. </p>
<p>So why did this bridge collapse? And, just as importantly, how might we make other bridges more safe against such collapse?</p>
<h2>A 20th century bridge meets a 21st century ship</h2>
<p>The Francis Scott Key Bridge was built through the mid 1970s and opened in 1977. The main structure over the navigation channel is a “continuous truss bridge” in three sections or spans.</p>
<p>The bridge rests on four supports, two of which sit each side of the navigable waterway. It is these two piers that are critical to protect against ship impacts.</p>
<p>And indeed, there were two layers of protection: a so-called “dolphin” structure made from concrete, and a fender. The dolphins are in the water about 100 metres upstream and downstream of the piers. They are intended to be sacrificed in the event of a wayward ship, absorbing its energy and being deformed in the process but keeping the ship from hitting the bridge itself.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/584647/original/file-20240327-28-cm4rr0.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Diagram of a bridge" src="https://images.theconversation.com/files/584647/original/file-20240327-28-cm4rr0.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/584647/original/file-20240327-28-cm4rr0.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=120&fit=crop&dpr=1 600w, https://images.theconversation.com/files/584647/original/file-20240327-28-cm4rr0.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=120&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/584647/original/file-20240327-28-cm4rr0.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=120&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/584647/original/file-20240327-28-cm4rr0.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=151&fit=crop&dpr=1 754w, https://images.theconversation.com/files/584647/original/file-20240327-28-cm4rr0.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=151&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/584647/original/file-20240327-28-cm4rr0.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=151&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Francis Scott Key Bridge in Baltimore, showing the pier struck by the cargo ship and the sections of bridge which collapsed as a result.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Francis_Scott_Key_Bridge_collapse#/media/File:2024_Francis_Scott_Key_Bridge_collapse.svg">F Vasconcellos / Wikimedia</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>The fender is the last layer of protection. It is a structure made of timber and reinforced concrete placed around the main piers. Again, it is intended to absorb the energy of any impact.</p>
<p>Fenders are not intended to <a href="https://iabse.org/Sys/Store/Products/296602">absorb impacts from very large vessels</a>. And so when the MV Dali, weighing more than 100,000 tonnes, made it past the protective dolphins, it was simply far too massive for the fender to withstand.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/ive-captained-ships-into-tight-ports-like-baltimore-and-this-is-how-captains-like-me-work-with-harbor-pilots-to-avoid-deadly-collisions-226700">I've captained ships into tight ports like Baltimore, and this is how captains like me work with harbor pilots to avoid deadly collisions</a>
</strong>
</em>
</p>
<hr>
<p>Video recordings show a cloud of dust appearing just before the bridge collapsed, which may well have been the fender disintegrating as it was crushed by the ship.</p>
<p>Once the massive ship had made it past both the dolphin and the fender, the pier – one of the bridge’s four main supports – was simply incapable of resisting the impact. Given the size of the vessel and its likely speed of around 8 knots (15 kilometres per hour), the impact force would have been <a href="https://iabse.org/Sys/Store/Products/296602">around 20,000 tonnes</a>.</p>
<h2>Bridges are getting safer</h2>
<p>This was not the first time a ship hit the Francis Scott Bridge. There was <a href="https://apps.dtic.mil/sti/tr/pdf/ADA135602.pdf">another collision in 1980</a>, damaging a fender badly enough that it had to be replaced. </p>
<p>Around the world, <a href="https://apnews.com/article/bridge-collapses-barges-list-1f2d6261d523ddc625aaaf3b32c626bc">35 major bridge collapses resulting in fatalities</a> were caused by collisions between 1960 and 2015, according to a 2018 report from the World Association for Waterborne Transport Infrastructure. Collisions between ships and bridges in the 1970s and early 1980s led to a significant improvement in the design rules for protecting bridges from impact.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/584643/original/file-20240327-30-727593.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A greenish book cover with the title Ship Collision With Bridges." src="https://images.theconversation.com/files/584643/original/file-20240327-30-727593.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/584643/original/file-20240327-30-727593.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=883&fit=crop&dpr=1 600w, https://images.theconversation.com/files/584643/original/file-20240327-30-727593.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=883&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/584643/original/file-20240327-30-727593.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=883&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/584643/original/file-20240327-30-727593.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1110&fit=crop&dpr=1 754w, https://images.theconversation.com/files/584643/original/file-20240327-30-727593.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1110&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/584643/original/file-20240327-30-727593.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1110&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Guidelines like this have played a crucial role in improved bridge safety.</span>
<span class="attribution"><a class="source" href="https://iabse.org/Sys/Store/Products/296602">IABSE</a></span>
</figcaption>
</figure>
<p><a href="https://link.springer.com/book/10.1007/978-3-319-73833-8">Further impacts</a> in the 1970s and early 1980s instigated significant improvements in the design rules for impact. </p>
<p>The International Association for Bridge and Structural Engineering’s <a href="https://iabse.org/Sys/Store/Products/296602">Ship Collision with Bridges</a> guide, published in 1993, and the American Association of State Highway and Transporation Officials’ <a href="https://store.transportation.org/Item/PublicationDetail?ID=1346">Guide Specification and Commentary for Vessel Collision Design of Highway Bridges</a> (1991) changed how bridges were designed.</p>
<p>In Australia, the <a href="https://www.standards.org.au/standards-catalogue/standard-details?designation=as-5100-2-2017">Australian Standard for Bridge Design</a> (published in 2017) requires designers to think about the biggest vessel likely to come along in the next 100 years, and what would happen if it were heading for any bridge pier at full speed. Designers need to consider the result of both head-on collisions and side-on, glancing blows. As a result, many newer bridges protect their piers with entire human-made islands.</p>
<p>Of course, these improvements came too late to influence the design of the Francis Scott Key Bridge itself.</p>
<h2>Lessons from disaster</h2>
<p>So what are the lessons apparent at this early stage? </p>
<p>First, it’s clear the protection measures in place for this bridge were not enough to handle this ship impact. Today’s cargo ships are much bigger than those of the 1970s, and it seems likely the Francis Scott Key Bridge was not designed with a collision like this in mind.</p>
<p>So one lesson is that we need to consider how the vessels near our bridges are changing. This means we cannot just accept the structure as it was built, but ensure the protection measures around our bridges are evolving alongside the ships around them.</p>
<p>Second, and more generally, we must remain vigilant in managing our bridges. I’ve written <a href="https://theconversation.com/are-australian-bridges-safe-and-can-we-do-better-101825">previously</a> about the current level of safety of Australian bridges, but also about how we can do better. </p>
<p>This tragic event only emphasises the need to spend more on maintaining our ageing infrastructure. This is the only way to ensure it remains safe and functional for the demands we put on it today.</p><img src="https://counter.theconversation.com/content/226716/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Colin Caprani receives funding from the Department of Transport (Victoria) and the Level Crossing Removal Project. He is also Chair of the Confidential Reporting Scheme for Safer Structures - Australasia, Chair of the Australian Regional Group of the Institution of Structural Engineers, and Australian National Delegate for the International Association for Bridge and Structural Engineering.</span></em></p>Bridges are getting safer – but their designers need to keep up with the ever-growing size of cargo ships.Colin Caprani, Associate Professor, Civil Engineering, Monash UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2238092024-03-26T12:39:43Z2024-03-26T12:39:43ZHow AI and a popular card game can help engineers predict catastrophic failure – by finding the absence of a pattern<figure><img src="https://images.theconversation.com/files/584159/original/file-20240325-10630-wq22k6.png?ixlib=rb-1.1.0&rect=84%2C498%2C1343%2C882&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Can you find a matching set?</span> <span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/File:Set_isomorphic_cards.svg">Cmglee/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>Humans are very good at <a href="https://doi.org/10.1016/j.neuron.2018.05.013">spotting patterns</a>, or repeating features people can recognize. For instance, ancient Polynesians navigated across the Pacific by <a href="https://nla.gov.au/nla.obj-318911458/view?partId=nla.obj-318923632#page/n90/mode/1up">recognizing many patterns</a>, from the stars’ constellations to more subtle ones such as the directions and sizes of ocean swells.</p>
<p>Very recently, <a href="https://scholar.google.com/citations?user=L1lKOGsAAAAJ&hl=en">mathematicians like me</a> have started to study large collections of objects that have no patterns of a particular sort. How large can collections be before a specified pattern has to appear somewhere in the collection? Understanding such scenarios can have significant real-world implications: For example, what’s the smallest number of server failures that would lead to the severing of the internet?</p>
<p>Research from mathematician <a href="https://scholar.google.com/citations?user=b7P6YbkAAAAJ&hl=en">Jordan Ellenberg</a> at the University of Wisconsin and researchers at <a href="https://deepmind.google/">Google’s Deep Mind</a> have proposed a novel approach to this problem. Their work <a href="https://doi.org/10.1038/s41586-023-06924-6">uses artificial intelligence to find</a> large collections that don’t contain a specified pattern, which can help us understand some worst-case scenarios.</p>
<h2>Patterns in the card game Set</h2>
<p>The idea of patternless collections can be illustrated by a popular card game <a href="https://brilliant.org/wiki/set-game/">called Set</a>. In this game, players lay out 12 cards, face up. Each card has a different simple picture on it. They vary in terms of number, color, shape and shading. Each of these four features can have one of three values.</p>
<p>Players race to look for “sets,” which are groups of three cards in which every feature is either the same or different in each card. For instance, cards with one solid red diamond, two solid green diamonds and three solid purple diamonds form a set: All three have different numbers (one, two, three), the same shading (solid), different colors (red, green, purple) and the same shape (diamond).</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/7AeEr9QtDF0?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Marsha Falco originally created the game Set to help explain her research on population genetics.</span></figcaption>
</figure>
<p>Finding a set is usually possible – but not always. If none of the players can find a set from the 12 cards on the table, then they flip over three more cards. But they still might not be able to find a set in these 15 cards. The players continue to flip over cards, three at a time, until someone spots a set.</p>
<p>So what is the maximum number of cards you can lay out without forming a set?</p>
<p>In 1971, mathematician Giuseppe Pellegrino showed that the <a href="https://www.quantamagazine.org/set-proof-stuns-mathematicians-20160531/">largest collection of cards without a set is 20</a>. But if you chose 20 cards at random, “no set” would happen only <a href="https://www-cs-faculty.stanford.edu/%7Eknuth/programs/setset-all.w">about one in a trillion times</a>. And finding these “no set” collections is an extremely hard problem to solve.</p>
<h2>Finding ‘no set’ with AI</h2>
<p>If you wanted to find the smallest collection of cards with no set, you could in principle do an exhaustive search of every possible collection of cards chosen from the deck of 81 cards. But there are an enormous number of possibilities – on the order of 10<sup>24</sup> (that’s a “1” followed by 24 zeros). And if you increase the number of features of the cards from four to, say, eight, the complexity of the problem would overwhelm any computer doing an exhaustive search for “no set” collections.</p>
<p>Mathematicians love to think about computationally difficult problems like this. These complex problems, if approached in the right way, can become tractable. </p>
<p>It’s easier to find best-case scenarios – here, that would mean the fewest number of cards that could contain a set. But there were few known strategies that could explore bad scenarios – here, that would mean a large collection of cards that do not contain a set.</p>
<p>Ellenberg and his collaborators approached the bad scenario with a type of AI called <a href="https://theconversation.com/ai-to-z-all-the-terms-you-need-to-know-to-keep-up-in-the-ai-hype-age-203917">large language models, or LLMs</a>. The researchers first wrote computer programs that generate some examples of collections of many that contain no set. These collections typically have “cards” with more than four features.</p>
<p>Then they fed these programs to the LLM, which soon learned how to write many similar programs and choose the ones that give rise to the largest set-free collections to undergo the process again. Iterating that process by repeatedly tweaking the most successful programs enables them to find larger and larger set-free collections.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/584175/original/file-20240325-28-3w7tk3.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Square of nine circles, four of which are colored blue, connected by grey, red, green, and yellow lines" src="https://images.theconversation.com/files/584175/original/file-20240325-28-3w7tk3.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/584175/original/file-20240325-28-3w7tk3.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/584175/original/file-20240325-28-3w7tk3.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/584175/original/file-20240325-28-3w7tk3.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/584175/original/file-20240325-28-3w7tk3.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/584175/original/file-20240325-28-3w7tk3.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/584175/original/file-20240325-28-3w7tk3.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">This is another version of a ‘no set,’ where no three components of a set are linked by a line.</span>
<span class="attribution"><a class="source" href="https://doi.org/10.1038/s41586-023-06924-6">Romera-Peredes et al./Nature</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>This method allows people to explore disordered collections – in this instance, <a href="https://doi.org/10.1038/s41586-023-06924-6">collections of cards that contain no set</a> – in an entirely new way. It does not guarantee that researchers will find the absolute worst-case scenario, but they will find scenarios that are much worse than a random generation would yield.</p>
<p>Their work can help researchers understand how events might align in a way that leads to catastrophic failure. </p>
<p>For example, how vulnerable is the electrical grid to a malicious attacker who destroys select substations? Suppose that a bad collection of substations is one where they don’t form a connected grid. The worst-case scenario is now a very large number of substations that, when taken all together, still don’t yield a connected grid. The amount of substations excluded from this collection make up the smallest number a malicious actor needs to destroy to deliberately disconnect the grid.</p>
<p>The work of Ellenberg and his collaborators demonstrates yet another way that AI is a very powerful tool. But to solve very complex problems, at least for now, it still needs human ingenuity to guide it.</p><img src="https://counter.theconversation.com/content/223809/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>John Edward McCarthy is partially supported by National Science Foundation Grant
DMS 2054199. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author and do not necessarily reflect the views of the National Science Foundation.</span></em></p>What mathematicians call ‘disordered collections’ can help engineers explore real-world worst-case scenarios. The simple card game Set illustrates how to predict internet and electrical grid failures.John Edward McCarthy, Professor of Mathematics, Arts & Sciences at Washington University in St. LouisLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2201902024-03-22T12:31:50Z2024-03-22T12:31:50ZThin, bacteria-coated fibers could lead to self-healing concrete that fills in its own cracks<figure><img src="https://images.theconversation.com/files/578396/original/file-20240227-26-c98ze5.jpg?ixlib=rb-1.1.0&rect=0%2C7%2C5176%2C3437&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Cracked roads and sidewalks generate big costs for cities. </span> <span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/CaliforniaDroughtRain/f93eda16ae2d49ad8539aaf1ad9eb92c/photo?Query=cracked%20concrete&mediaType=photo&sortBy=&dateRange=Anytime&totalCount=260&digitizationType=Digitized&currentItemNo=17&vs=true&vs=true">AP Photo/Marcio Jose Sanchez</a></span></figcaption></figure><p>Some say there are two types of concrete – cracked and on the brink of cracking. But what if when concrete cracked, it could heal itself? </p>
<p><a href="https://research.coe.drexel.edu/caee/aim/">We’re part of a team</a> of <a href="https://scholar.google.com/citations?user=Tn72mFcAAAAJ&hl=en">materials</a> <a href="https://scholar.google.com/citations?user=AtY08c4AAAAJ&hl=en">scientists</a> and microbiologists that has <a href="https://theconversation.com/calcium-munching-bacteria-could-be-a-secret-weapon-against-road-salt-eating-away-at-concrete-roads-and-bridges-113970">harnessed the power of bacteria</a> to create biological fibers that <a href="https://doi.org/10.1016/j.conbuildmat.2023.133765">initial results suggest</a> can heal cracks in concrete. We’re working on a technology that, if we work out the kinks and manage to bring it to the market one day, could extend the life span of concrete.</p>
<h2>Cracking concrete</h2>
<p>Picture a bridge exposed to snow, rain, temperature changes and trucks carrying heavy loads. The concrete on the bridge will gradually develop cracks from stress and wear. Over time, these cracks expand, allowing water and corrosive substances that weaken the concrete to penetrate further down. </p>
<p>At some point, local authorities have to pay for repairs, which are not only expensive but also <a href="https://artbabridgereport.org/reports/2022-ARTBA-Bridge-Report.pdf">disrupt traffic and drain public resources</a>.</p>
<p>Now, consider a medical patient recovering from a severe injury. As the patient’s cells recognize the damage, they release tiny healing agents – like microscopic repair crews. These agents target the wounded area, mending tissues and restoring the cells’ functionality. What if concrete had the same kind of <a href="https://doi.org/10.1038/nmat1934">self-healing ability</a> as human tissue? </p>
<h2>A self-healing concrete</h2>
<p><a href="https://research.coe.drexel.edu/caee/aim/people/">Our team</a> at the <a href="https://research.coe.drexel.edu/caee/aim/">Advanced Infrastructure Materials lab</a> at Drexel University was inspired by self-healing tissue in the human body. We developed an addition to concrete we <a href="https://doi.org/10.1016/j.conbuildmat.2023.133765">call BioFiber</a>.</p>
<p>BioFiber has <a href="https://doi.org/10.1016/j.conbuildmat.2023.133765">three essential functions</a>: It heals itself on its own, it stops cracks from growing wider, and it remains intact inside the concrete when there aren’t any cracks. </p>
<p>Each BioFiber has <a href="https://doi.org/10.1016/j.conbuildmat.2023.133765">three key components</a>: a tough core fiber made of a polymer called polyvinyl alcohol, a porous layer of hydrogel infused with <em><a href="https://www.sciencedirect.com/topics/immunology-and-microbiology/lysinibacillus-sphaericus">Lysinibacillus sphaericus</a></em> bacteria, and a damage-responsive outer shell. When cracks hit the BioFiber, its outer shell breaks and releases the bacteria into the crack, which starts the self-healing process.</p>
<p>The strong core fibers in BioFiber <a href="https://doi.org/10.1016/j.conbuildmat.2023.133765">bridge the cracks</a> and stop them from growing wider during the healing process.</p>
<p>Surrounding the core fiber, the hydrogel layer is made up of a mesh of polymer chains at the molecular level that attract water. Their spongelike structure can absorb and hold large volumes of water. During the production process, we add calcium to help the hydrogel solidify. </p>
<p>The hydrogel itself is made up of a <a href="https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/alginate">natural polymer found in seaweed called alginate</a>, which has special properties that allow it to trap bacteria. Alginate isn’t toxic and is even safe for biomedical applications such as <a href="https://doi.org/10.1155/2020/8886095">drug delivery</a> and <a href="https://doi.org/10.3390/md21030189">tissue engineering</a>.</p>
<p>The hydrogel <a href="https://www.ncbi.nlm.nih.gov/books/NBK556071">houses endospores</a>, which are dormant bacteria. Once the outer shell cracks and the endospores are awakened from their dormant state, they facilitate the self-healing. </p>
<h2>Activating BioFiber</h2>
<p>The endospores need water to activate. Luckily, the middle hydrogel layer absorbs water well. When the concrete cracks, and water from rain, humidity or street runoff seeps in, the spores wake up. </p>
<p>The spores ingest carbon that we specifically add into the concrete mix, as well as calcium in the concrete itself. With these materials, the bacteria facilitates a chemical reaction called microbially induced calcium carbonate precipitation, or MICCP. This reaction creates <a href="https://doi.org/10.1016/j.dibe.2024.100351">calcium carbonate crystals</a>, which build up and fill in the cracks in the concrete.</p>
<p>The crystal shape varies, from sphere to needle-shaped, and each shape is strong enough to heal the cracks. We can alter the type of crystals the bacteria produces by changing the pH level, calcium source and type of bacteria.</p>
<p>Concrete acts like a solid, tough substance because it’s a mix of cement, sand, gravel and water. We toss the BioFibers into the mix and spread them out as the concrete is mixed, ensuring they’re evenly distributed throughout the mixture.</p>
<p>Once the self-healing process ends and the bacteria dies, the activated BioFiber is done – it can’t heal anymore. But since the concrete has many BioFibers distributed throughout, another fiber can mend the next crack. At the moment, we do not know how many cracks BioFiber concrete can heal, and we’re conducing more research to figure that out. </p>
<p>To feed the bacteria, we add the amount of food it needs to stay alive and heal the cracks, depending on how many cracks we anticipate them having to fix. When the bacteria runs out of food, the process stops. The bacteria can live for roughly a couple of weeks during the healing process. </p>
<p>While BioFiber shows initial promise, it does have shortcomings, which could make manufacturing it at a larger scale challenging. The manufacturing process and materials used are specialized and not always affordable and practical. While our first tests suggest that BioFiber extends the life span of concrete, we’ll need more testing, including field trials, to verify those early results.</p>
<p>We hope to eventually commercialize and manufacture the fibers at larger production scales, while in the meantime we continue to run tests and study how to improve BioFiber’s self-healing abilities. We’d like to one day get these fibers into roads and sidewalks to potentially prevent cracking in aging concrete.</p><img src="https://counter.theconversation.com/content/220190/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mohammad Houshmand works for Drexel University. He receives funding from the National Science Foundation.</span></em></p><p class="fine-print"><em><span>Yaghoob Farnam receives funding from the National Science Foundation. In addition to his role as an associate professor at Drexel University, he is co-founder and senior technical advisor for SusMaX Inc. </span></em></p>Your skin heals from cuts and scrapes on its own − what if concrete could do that too?Mohammad Houshmand, Ph.D. Candidate in Civil Engineering, Drexel UniversityYaghoob Farnam, Assistant Professor of Civil Engineering, Drexel UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2256752024-03-14T05:47:43Z2024-03-14T05:47:43ZShould you be concerned about flying on Boeing planes?<p>The American aerospace giant Boeing has been synonymous with safe air travel for decades. Since the 1990s, Boeing and its European competitor Airbus have dominated the market for large passenger jets. </p>
<p>But this year, Boeing has been in the news for all the wrong reasons. In January, an emergency door plug <a href="https://www.seattletimes.com/business/boeing-aerospace/alaska-airlines-let-boeing-max-fly-despite-warning-signals">blew off a Boeing 737 MAX</a> in mid flight, triggering an investigation from United States federal regulators. </p>
<p>More recently, we have seen a Boeing plane lose a tyre while taking off, another flight turned back as the plane was leaking fluid, an apparent engine fire, a landing gear collapse, a stuck rudder pedal, and a plane “dropping” in flight and <a href="https://theconversation.com/latam-flight-800-just-dropped-in-mid-flight-injuring-dozens-an-expert-explores-what-happened-and-how-to-keep-yourself-safe-225554">injuring dozens of passengers</a>. A Boeing engineer who had raised concerns regarding quality control during the manufacturing process on the company’s 787 and 737 MAX planes also <a href="https://www.bbc.com/news/business-68534703">died earlier this week</a>, apparently of a self-inflicted gunshot wound. </p>
<p>As members of the travelling public, should we be concerned? Well, yes and no.</p>
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<strong>
Read more:
<a href="https://theconversation.com/boeing-door-plug-blowout-highlights-a-possible-crisis-of-competence-an-aircraft-safety-expert-explains-221069">Boeing door plug blowout highlights a possible crisis of competence − an aircraft safety expert explains</a>
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<h2>Many problems, but not all can be blamed on Boeing</h2>
<p>The recent parade of events has certainly been dramatic – but not all of them can be blamed on Boeing. Five incidents occurred on aircraft owned and operated by United Airlines and were related to factors outside the manufacturer’s control, like maintenance issues, potential foreign object debris, and possible human error. </p>
<p>A <a href="https://www.independent.co.uk/travel/news-and-advice/united-airlines-plane-tire-blowout-boeing-b2509241.html">United Airlines 777</a> flying from San Francisco to Japan lost a tyre on takeoff, a maintenance issue not related to Boeing. The aircraft landed safely in Los Angeles. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1767636549288824990"}"></div></p>
<p>A <a href="https://www.mercurynews.com/2024/03/12/united-airlines-reports-fifth-flight-incident-in-a-week-as-jet-turns-back-due-to-maintenance-issue/">United Airlines flight from Sydney</a> to Los Angeles had to return to Sydney due to a “maintenance issue” after a fluid was seen leaking from the aircraft on departure. </p>
<p>A <a href="https://www.nbcnews.com/news/us-news/passenger-video-shows-flames-shoot-united-airlines-engine-midflight-rcna142217">United Airlines 737-900</a> flying from Texas to Florida ended up with some plastic bubble wrap in the engine, causing a suspected <a href="https://skybrary.aero/articles/compressor-stall#:%7E:text=Compressor%20stalls%20cause%20the%20air,dirty%20or%20contaminated%20compressor%20components">compressor stall</a>. This is a disruption of air flow to an operating engine, making it “backfire” and emit flames. </p>
<p>A <a href="https://simpleflying.com/united-boeing-737-max-houston-runway-incident/">United Airlines 737 Max</a> flying from Tennessee to Texas suffered a gear collapse after a normal landing. The pilot continued to the end of the runway before exiting onto a taxiway – possibly at too high a speed – and the aircraft ended up in the grass and the left main landing gear collapsed. </p>
<p>The fifth event occurred on a <a href="https://www.nbcnews.com/news/us-news/another-boeing-max-mishap-ntsb-probes-stuck-rudder-pedals-united-airli-rcna142286">United Airlines 737-8</a> flight from the Bahamas to New Jersey. The pilots reported that the rudder pedals, which control the left and right movement of the aircraft in flight, were stuck in the neutral position during landing.</p>
<h2>Manufacturing quality concerns</h2>
<p>The <a href="https://www.seattletimes.com/business/boeing-aerospace/alaska-airlines-let-boeing-max-fly-despite-warning-signals">exit door plug failure in January</a> occurred on an Alaska Airlines flight. US regulators are currently investigating Boeing’s <a href="https://www.vox.com/money/24052245/boeing-corporate-culture-737-airplane-safety-door-plug">manufacturing quality assurance</a> as a result. </p>
<p>The door plug was installed by a Boeing subcontractor called Spirit AeroSystem. The door plug bolts were not properly secured and the plug door fell off in flight. The same aircraft had a series of pressurisation alarms on two previous flights, and was scheduled for a maintenance inspection at the completion of the flight. </p>
<p>Spirit got its start after Boeing shut down its own manufacturing operations in Kansas and Oklahoma, and Boeing is now in the process of <a href="https://www.cnbc.com/2024/03/01/spirit-aerosystems-boeing.html">buying the company</a> to improve quality oversight. Spirit currently works with Airbus, as well, though that may change.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-did-alaska-airlines-flight-1282-have-a-sealed-off-emergency-exit-in-the-first-place-the-answer-comes-down-to-money-221263">Why did Alaska Airlines Flight 1282 have a sealed-off emergency exit in the first place? The answer comes down to money</a>
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<h2>What changed at Boeing</h2>
<p>Critics say the <a href="https://www.washingtonpost.com/business/2024/03/12/boeing-whistleblower-death-plane-issues/">culture at Boeing has changed</a> since Airbus became a major competitor in the early 2000s. The company has been accused of shifting its focus to profit at the expense of quality engineering. </p>
<p>Former staff have raised concerns over tight production schedules, which increased the pressure on employees to finish the aircraft. This caused many engineers to question the process, and the US Federal Aviation Administration (FAA) to fine Boeing for lapses in quality oversight after tools and debris were found on aircraft being inspected. </p>
<p>Several employees have testified before US Congress on the production issues regarding quality control. Based on the congressional findings, the FAA began to inspect Boeing’s processes more closely.</p>
<p>Several Boeing employees noted there was a high staff turnover rate during the COVID pandemic. This is not unique to Boeing, as all manufacturing processes and airline maintenance facilities around the globe were also hit with high turnover. </p>
<p>As a result, there is an acute shortage of qualified maintenance engineers, as well as pilots. These shortages have created several issues with the airline industry successfully returning to the <a href="https://www.aviationbusinessnews.com/mro/critical-shortage-of-engineers-means-looming-crisis-for-aviation-warns-aeroprofessional/">pre-pandemic levels</a> of 2019. Airlines and maintenance training centres around the globe are working hard to train replacements, but this takes time as one cannot become a qualified engineer or airline pilot overnight.</p>
<p>So, is it still safe to fly on Boeing planes? Yes it is. Despite dramatic incidents in the news and social media posts <a href="https://twitter.com/DaveMcNamee3000/status/1767636549288824990">poking fun at the company</a>, air travel is still extremely safe, and that includes Boeing.</p>
<p>We can expect these issues with Boeing planes now will be corrected. The financial impact has been significant – so even a profit-driven company will demand change.</p><img src="https://counter.theconversation.com/content/225675/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Doug Drury does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>The American aerospace company Boeing has been synonymous with safe air travel for decades, but recent weeks have seen it plagued by a series of issues.Doug Drury, Professor/Head of Aviation, CQUniversity AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2255542024-03-12T02:18:16Z2024-03-12T02:18:16ZLATAM flight 800 ‘just dropped’ in mid-flight, injuring dozens. An expert explores what happened, and how to keep yourself safe<figure><img src="https://images.theconversation.com/files/581149/original/file-20240312-18-cpokru.jpeg?ixlib=rb-1.1.0&rect=12%2C38%2C4224%2C2776&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/los-angelescalifornia-january-14-2017-latam-558269083">Shutterstock</a></span></figcaption></figure><p>On Monday, LATAM Airlines flight 800 from Sydney to Auckland experienced what officials are describing as a “technical fault” that meant the <a href="https://edition.cnn.com/2024/03/11/australia/new-zealand-latam-airlines-intl-hnk/index.html">Boeing 787-9 Dreamliner</a> “<a href="https://www.reuters.com/world/asia-pacific/24-injured-after-technical-problem-latam-sydney-auckland-flight-nz-herald-2024-03-11/">just dropped</a>” without any warning. </p>
<p>The aircraft pitched downward very quickly, causing some passengers and crew members who were not wearing seatbelts to hit the ceiling, and leaving at least 50 people injured. The flight landed without further incident and the injured passengers and crew were transferred to local hospitals.</p>
<p>So what happened? And should air passengers be concerned?</p>
<p>The short answer is there’s no need to worry – if anything, it seems the plane’s safety systems worked as intended. The real takeaway from the story is you should always wear your seatbelt while seated, just like the cabin crew have been telling you.</p>
<h2>Keep perspective</h2>
<p>When we plan a trip, we usually have adventure or work on our minds as we wing our way to our destination. We think about what types of activities we’ll do, like hiking or water sports, and where we can find great meals. </p>
<p>Most of us never think about what is happening up front in the cockpit as we watch a movie or enjoy the in-flight meal. We generally don’t feel the need to worry about the flights as we feel confident we’ll get to our destination without a problem. Airline incidents are rare when you consider how much travelling is taking place around the globe.</p>
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<strong>
Read more:
<a href="https://theconversation.com/could-climate-change-have-played-a-role-in-the-airasia-crash-36002">Could climate change have played a role in the AirAsia crash?</a>
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<p>On peak travel days, there can be more than <a href="https://www.travelweek.ca/news/exactly-many-planes-world-today/">16,000 planes in the air</a> at any time. There are around 4 billion air travel passengers each year, and the number is <a href="https://www.airlineratings.com/news/airline-passengers-tipped-to-double-by-2035/">expected to double by 2035</a> by some estimates.</p>
<p>The vast majority of these flights pass without incident. However, when an emergency does occur it receives a lot of attention – a lot more attention than the far more frequent crashes or other accidents that happen on our roads, for example.</p>
<p>So when you do hear about an incident on a plane, the first thing to do is keep it in perspective.</p>
<h2>What happened on LATAM 800?</h2>
<p>Authorities have not released a lot of detail on the cause of the incident, beyond saying it was a “technical fault”. As LATAM Flight 800 originated in Australia, the transportation investigation teams from Australia, New Zealand, Boeing and LATAM will scrutinise the incident to better understand what happened. </p>
<p>Modern airliners have redundant systems for flight-critical controls. If one fails, it can be transferred to the backup automatically or manually by the flight crew. </p>
<p>One passenger stated that one of the <a href="https://www.news.com.au/travel/travel-updates/incidents/fifty-injured-after-pilot-lost-instrumentation-on-latam-flight-from-sydney-to-auckland/news-story/e713c49fd1332b06950d802d57cecb35">pilots said his instruments went blank</a>, he lost control briefly, and the backup system returned the aircraft back to normal operations. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1767346331448742364"}"></div></p>
<p>If the aircraft experienced a sudden loss of electrical power – from a generator failure, for example – it would cause the autopilot to fail as well. This could have caused the aircraft to abruptly change its flight configuration and descend rapidly. </p>
<p>Whatever happened in this case, it seems the redundant systems on the 787, <a href="https://simpleflying.com/united-787-9-generator-failure/">which includes six backup generators</a>, were able to rapidly return all systems to normal. </p>
<h2>Wear your seatbelt</h2>
<p>LATAM 800 is an example of why we should always wear seatbelts when we are seated on an airplane. While technical faults of this kind are rare, turbulence is a much more common occurrence that can lead to injuries for unsecured passengers.</p>
<p>The <a href="https://www.npr.org/2023/03/05/1161196591/turbulence-airplanes-injuries-death-safety">US Federal Aviation Administration</a> has reported that, in the United States, 30 passengers and 116 crew members were hospitalised due to in-flight injuries caused by turbulence between 2009 and 2021. </p>
<p>Crew members are most susceptible due to the nature of their job. The <a href="https://www.atsb.gov.au/publications/2014/in-flight-turbulence">Federal Aviation Administration states</a> the annual cost to the global aviation industry due to turbulence injuries is US$100 million.</p>
<h2>Climate change and turbulence</h2>
<p>With climate change heating up our atmosphere every year, we can expect more turbulence. Wind speeds at the altitudes where most aircraft fly are increasing, <a href="https://www.forbes.com/sites/marisagarcia/2023/11/20/more-clear-air-turbulence-from-climate-change-raises-safety-concerns/?sh=18be6a894b39">causing more turbulence</a>.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/what-is-air-turbulence-196872">What is air turbulence?</a>
</strong>
</em>
</p>
<hr>
<p>This type of turbulence is known as “clear air turbulence” and is difficult to predict or see with current aircraft technologies. <a href="https://www.forbes.com/sites/marisagarcia/2023/11/20/more-clear-air-turbulence-from-climate-change-raises-safety-concerns/?sh=18be6a894b39">Researchers have</a> found that severe clear air turbulence over the North Atlantic increased by 55% from 1979 to 2020. </p>
<p>For airlines, more turbulence will mean more wear and tear on aircraft. But for travellers, the bottom line is clear: always follow the safety instructions from the cabin crew, and keep your seatbelt fastened at all times when seated.</p><img src="https://counter.theconversation.com/content/225554/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Doug Drury does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>It’s unclear exactly what happened to violently shake up LATAM flight 800, but the moral for passengers is clear: wear your seatbelt.Doug Drury, Professor/Head of Aviation, CQUniversity AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2225712024-03-05T14:00:28Z2024-03-05T14:00:28ZLithium-ion batteries don’t work well in the cold − a battery researcher explains the chemistry at low temperatures<figure><img src="https://images.theconversation.com/files/579001/original/file-20240229-20-z7oy0y.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C2120%2C1414&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Why do batteries lose charge more quickly when it's cold? </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/man-charging-electric-car-in-front-his-cabin-in-royalty-free-image/1977511649?phrase=battery+cold&adppopup=true">Halfpoint Images/Moment</a></span></figcaption></figure><p>Rechargeable batteries are great for storing energy and powering electronics from smartphones to electric vehicles. In cold environments, however, they can be more difficult to charge and may even catch on fire. </p>
<p>I’m a mechanical engineering professor who’s been interested in batteries since college. I now lead a <a href="https://research.drexel.edu/mem/changlab">battery research group</a> at Drexel University. </p>
<p>In just this past decade, I have watched the <a href="https://about.bnef.com/blog/lithium-ion-battery-pack-prices-hit-record-low-of-139-kwh/">price of lithium-ion batteries drop</a> as the production market <a href="https://www.iea.org/reports/global-ev-outlook-2023/trends-in-batteries">has grown much larger</a>. Future projections predict the market could reach <a href="https://www.mckinsey.com/industries/automotive-and-assembly/our-insights/battery-2030-resilient-sustainable-and-circular">thousands of GWh per year by 2030</a>, a significant increase. </p>
<p>But, lithium-ion batteries aren’t perfect – this rise comes with risks, such as their tendency to slow down during cold weather and even catch on fire.</p>
<h2>Behind the Li-ion battery</h2>
<p>The <a href="https://www.sciencedirect.com/topics/chemistry/electrochemical-energy-storage">electrochemical energy storage</a> within batteries works by storing electricity <a href="https://www.britannica.com/science/ion-physics">in the form of ions</a>. Ions are atoms that have a nonzero charge because they have either too many or not enough electrons. </p>
<p>When you plug in your electric car or phone, the electricity provided by the outlet <a href="https://www.youtube.com/watch?v=4-1psMHSpKs&ab_channel=TheLimitingFactor">drives these ions</a> from the battery’s positive electrode into its negative electrode. The electrodes are solid materials in a battery that can store ions, and all batteries have both a positive and a negative electrode. </p>
<p>Electrons pass through the battery as electricity. With each electron that passes to one electrode, a lithium ion also passes into the same electrode. This ensures the balance of charges in the battery. As you drive your car, the stored ions in the negative electrode move back to the positive electrode, and the resulting flow of electricity powers the motor. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/578759/original/file-20240228-8828-q6kh1t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A diagram showing three boxes, one labeled cathode, one labeled electrolyte, and one labeled anode. Small circles representing lithium ions move to the anode to charge and the cathode to discharge." src="https://images.theconversation.com/files/578759/original/file-20240228-8828-q6kh1t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/578759/original/file-20240228-8828-q6kh1t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=564&fit=crop&dpr=1 600w, https://images.theconversation.com/files/578759/original/file-20240228-8828-q6kh1t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=564&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/578759/original/file-20240228-8828-q6kh1t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=564&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/578759/original/file-20240228-8828-q6kh1t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=708&fit=crop&dpr=1 754w, https://images.theconversation.com/files/578759/original/file-20240228-8828-q6kh1t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=708&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/578759/original/file-20240228-8828-q6kh1t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=708&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">When a lithium-ion battery delivers energy to a device, lithium ions – atoms that carry an electrical charge – move from the negative electrode, the anode, to the positive electrode, the cathode. The ions move in reverse when recharging.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/argonne/5029455937">Argonne National Laboratory</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-sa/4.0/">CC BY-NC-SA</a></span>
</figcaption>
</figure>
<p>While AA or AAA batteries can power small electronics, they can be used only once and cannot be charged. Rechargeable Li-ion batteries can operate for thousands of cycles of full charge and discharge. For each cycle, they can also store a much higher amount of charge than an AA or AAA battery.</p>
<p>Since lithium is the lightest metal, it has a high <a href="https://doi.org/10.1039/C3EE40795K">specific capacity</a>, meaning it can store a <a href="https://chang-lab.notion.site/How-To-Become-a-Battery-Expert-20a8edebe395403c9a158d7caca06ef4?pvs=4">huge amount of charge per weight</a>. This is why lithium-ion batteries are useful not just for portable electronics but for powering modes of transportation with limited weight or volume, such as electric cars. </p>
<h2>Battery fires</h2>
<p>However, lithium-ion batteries have risks that AA or AAA batteries don’t. For one, they’re more likely to catch on fire. For example, the number of <a href="https://gothamist.com/news/e-bike-battery-fires-keep-climbing-in-nyc">electric bike battery fires</a> reported in New York City has increased from 30 to nearly 300 in the past five years. </p>
<p>Lots of different issues can cause a battery fire. Poorly manufactured cells could contain defects, such as trace impurities or particles left behind from the manufacturing process, that increase the risk of an internal failure. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/578754/original/file-20240228-30-b8mmfs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A car in a garage is on fire with the door cracked open, a firefighter carrying a hose runs towards it." src="https://images.theconversation.com/files/578754/original/file-20240228-30-b8mmfs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/578754/original/file-20240228-30-b8mmfs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=396&fit=crop&dpr=1 600w, https://images.theconversation.com/files/578754/original/file-20240228-30-b8mmfs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=396&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/578754/original/file-20240228-30-b8mmfs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=396&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/578754/original/file-20240228-30-b8mmfs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=497&fit=crop&dpr=1 754w, https://images.theconversation.com/files/578754/original/file-20240228-30-b8mmfs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=497&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/578754/original/file-20240228-30-b8mmfs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=497&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The lithium-ion batteries in electric vehicles have a higher risk of catching on fire when it’s cold out.</span>
<span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/ElectricCarsBatteryFires/0624a4c4cadb4ee0be42d58b8aab0161/photo?Query=ev%20battery%20fire&mediaType=photo&sortBy=&dateRange=Anytime&totalCount=300&digitizationType=Digitized&currentItemNo=0&vs=true&vs=true">Orange County Sheriff’s Department/National Transportation Safety Board via AP</a></span>
</figcaption>
</figure>
<p>Climate can also affect battery operation. <a href="https://about.bnef.com/electric-vehicle-outlook/">Electric vehicle sales</a> have increased across the U.S., particularly in cold regions such as the Northeast and Midwest, where the frigid temperatures can hinder battery performance. </p>
<p>Batteries contain fluids called electrolytes, and cold temperatures cause fluids to flow more slowly. So, the electrolytes in batteries slow and thicken in the cold, causing the lithium ions inside to move slower. This slowdown can prevent the lithium ions from properly inserting into the electrodes. Instead, they may deposit on the electrode surface and form <a href="https://doi.org/10.1016/j.xcrp.2020.100035">lithium metal</a>. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/G_TCFgEdEGc?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">The molecules in fluids move slower at colder temperatures – the same thing happens inside batteries.</span></figcaption>
</figure>
<p>If too much lithium deposits on the electrode’s surface during charging, it may cause an internal short circuit. This process can <a href="https://theconversation.com/lithium-ion-battery-fires-are-a-growing-public-safety-concern-heres-how-to-reduce-the-risk-209359">start a battery fire</a>.</p>
<h2>Making safer batteries</h2>
<p><a href="https://research.coe.drexel.edu/mem/changlab">My research group</a>, along with many others, is studying how to make batteries that operate more efficiently in the cold. </p>
<p>For example, researchers are exploring swapping out the usual battery electrolyte and replacing it with an alternative electrolyte that doesn’t thicken at cold temperatures. Another potential option is <a href="https://www.washingtonpost.com/climate-solutions/2024/01/19/electric-vehicle-battery-cold/">heating up the battery pack</a> before charging so that the charging process occurs at a warmer temperature. </p>
<p>My group is also investigating new types of batteries beyond lithium ion. These could be battery types that are more stable at wider temperature ranges, types that don’t even use liquid electrolytes at all, or batteries that use sodium instead of lithium. <a href="https://www.technologyreview.com/2023/05/11/1072865/how-sodium-could-change-the-game-for-batteries/">Sodium-ion batteries</a> could work well and cost less, as sodium is a very abundant resource.</p>
<p><a href="https://doi.org/10.1038/s41560-023-01208-9">Solid-state batteries</a> use solid electrolytes that aren’t flammable, which reduces the risk of fire. But these batteries don’t work quite as well as Li-ion batteries, so it’ll take more research to tell whether these are a good option.</p>
<p>Lithium-ion batteries power technologies that people across the country use every day, and research in these areas aims to find solutions that will make this technology even safer for the consumer.</p><img src="https://counter.theconversation.com/content/222571/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Wesley Chang receives funding from Solid Energy Systems, Inc., Electric Power Research Institute, Drexel University. Wesley Chang consults for The Electrochemical Society. </span></em></p>Electric vehicles are catching on across the US, but they’re also catching on fire in colder regions like the Northeast and Midwest.Wesley Chang, Assistant Professor of Mechanical Engineering and Mechanics, Drexel UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2141262024-02-20T13:29:38Z2024-02-20T13:29:38Z3D printing promises more efficient ways to make custom explosives and rocket propellants<figure><img src="https://images.theconversation.com/files/575456/original/file-20240213-26-q2ug1p.jpg?ixlib=rb-1.1.0&rect=6%2C3%2C2111%2C1406&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">3D printing can be used to build with all kinds of materials – even those that go 'boom.'</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/printer-printing-prototypes-royalty-free-image/1459229120?phrase=3D+printer&adppopup=true">kynny/iStock via Getty Images</a></span></figcaption></figure><p>Imagine you’re driving to work on a rainy day, when a distracted, reckless driver hits your car out of nowhere. With a “boom,” an air bag deploys faster than you can <a href="https://www.nhtsa.gov/vehicle-safety/air-bags">blink your eyes</a> to save your life. </p>
<p>That air bag deployed rapidly thanks to an energetic material called <a href="https://cen.acs.org/safety/chemicals-make-airbags-inflate-changed/100/i41">sodium azide</a>, which generates nitrogen gas during a chemical reaction to inflate your airbag. But what’s an energetic material? </p>
<p>Energetic materials include <a href="https://www.osti.gov/biblio/1765628">propellants, pyrotechnics, fuels and explosives</a>, and they’re used in all sorts of settings. </p>
<p>Uses of energetic materials include <a href="https://www.explainthatstuff.com/flares.html">flares</a>, <a href="https://www.compoundchem.com/2014/11/20/matches/">matches</a>, <a href="https://www.youtube.com/watch?v=a1Ef1PcPKjk">solid rocket boosters</a>, <a href="https://www.ict.fraunhofer.de/en/comp/em/treib.html">gun propellants</a>, hot <a href="https://www.twi-global.com/technical-knowledge/faqs/what-is-cad-welding">thermite welding</a> used to fuse materials together, <a href="https://theconversation.com/how-do-fireworks-work-a-pyrotechnics-chemist-explains-the-science-behind-the-brilliant-colors-and-sounds-173576">fireworks</a> and the <a href="https://www.gq.com/video/watch/the-breakdown-gq-the-breakdown-explosions">explosive special effects</a> in your favorite action movie. </p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/575457/original/file-20240213-30-hajfxf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A gold and white rocket, with flames coming out of its end, attached to a concrete scaffold." src="https://images.theconversation.com/files/575457/original/file-20240213-30-hajfxf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/575457/original/file-20240213-30-hajfxf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=750&fit=crop&dpr=1 600w, https://images.theconversation.com/files/575457/original/file-20240213-30-hajfxf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=750&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/575457/original/file-20240213-30-hajfxf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=750&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/575457/original/file-20240213-30-hajfxf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=943&fit=crop&dpr=1 754w, https://images.theconversation.com/files/575457/original/file-20240213-30-hajfxf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=943&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/575457/original/file-20240213-30-hajfxf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=943&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Propellants help rockets blast off.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Rocket_propellant#/media/File:Delta_IV_launch_2013-08-28.jpg">U.S. Air Force/Joe Davila</a></span>
</figcaption>
</figure>
<p>Energetic materials come in many shapes and sizes, but they’re often in a solid form and release a lot of energy through <a href="https://www.nfpa.org/news-blogs-and-articles/blogs/2023/03/27/explosions-vs-deflagrations-vs-detonations">burning or exploding</a>, depending on their shape and the conditions they’re operating in. </p>
<p>I’m a <a href="https://www.technologyreview.com/innovator/monique-mcclain/">mechanical engineering professor</a> who studies <a href="https://scholar.google.com/citations?user=whbrwS0AAAAJ&hl=en">energetic materials</a>. Making energetic materials isn’t easy, but developments in 3D printing could make customization easier, while allowing for more potential scientific applications. </p>
<h2>The role of geometry</h2>
<p>How energetic materials are made affects the shapes that they come in and how they release energy over time. For example, solid rocket propellants are made <a href="https://www.youtube.com/watch?v=E0bnPb1WIuc">similar to a cake</a> where a stand mixer stirs the “batter,” which is mostly made of <a href="https://blogs.nasa.gov/Rocketology/tag/ammonium-perchlorate/">ammonium perchlorate, aluminum and a rubbery binder</a>, before it’s poured into a pan. The “cake” solidifies in the pan while it bakes in the oven. </p>
<p>Typically, rocket propellants have a cylindrical shape, but with a rod in the center. <a href="https://airandspace.si.edu/collection-objects/mandrel-rocket-manufacturing-solid-propellant-rocket-motor/nasm_A20060526000">The rod</a> often has a specific <a href="https://www.nakka-rocketry.net/th_grain.html">cross-sectional shape</a>, like a circle or a star. When the propellant solidifies, the rod is removed, leaving the core shape behind. </p>
<p>The core shape affects how the propellant burns, which can affect the <a href="https://www.youtube.com/watch?v=eVvIZ3f2tSU">thrust of the motor it’s used in</a>. Just by changing the central shape of the propellant, you can make a motor accelerate, slow down or maintain its speed over time. </p>
<p>But this traditional “cake baking” process limits the shapes that you can make. You must be able to remove the rod after the propellant solidifies, so if the rod’s shape is too complex, you might break the propellant, which could make it burn erratically. </p>
<p>Designing propellant shapes that make rockets go faster or fly farther is an active area of research, but engineers need new manufacturing methods to create these increasingly complex designs.</p>
<h2>3D printing to the rescue</h2>
<p><a href="https://www.pcmag.com/news/3d-printing-what-you-need-to-know">3D printing</a> has revolutionized manufacturing in a variety of ways, and researchers like me are trying to understand how it can improve the performance of energetic materials. 3D printing uses a printer to stack up material <a href="https://www.youtube.com/watch?v=Vx0Z6LplaMU">layer by layer</a> to build an object. </p>
<p>3D printing allows you to make custom shapes, print multiple types of material in one part, and save money and material. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/Vx0Z6LplaMU?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">3D printing can be cost- and time-efficient.</span></figcaption>
</figure>
<p>However, it is very challenging to 3D-print energetic materials for several reasons. Some <a href="https://ntrs.nasa.gov/citations/19720024117">energetic materials are very viscous</a>, which means it is very hard to squeeze that mixture out of a tube with a small nozzle. Imagine squeezing clay out of a small syringe – the material is too thick to easily move through the small hole. </p>
<p>In addition, energetic materials can be dangerous if handled improperly. They can ignite if there is <a href="https://www.osti.gov/servlets/purl/639810">too much heat</a> during the manufacturing process or during storage, or if they are exposed to a <a href="https://apps.dtic.mil/sti/tr/pdf/ADA322856.pdf">static electric shock</a>.</p>
<h2>Recent progress</h2>
<p>Despite this, researchers have made a lot of progress in the <a href="https://doi.org/10.1002/prep.201900060">past decade</a> to overcome some of these challenges. For example, scientists have 3D-printed <a href="https://engineering.purdue.edu/ME/News/inkjetprinted-thermite-combines-energetic-materials-and-additive-manufacturing">reactive inks onto electronics</a> to enable self-destruction if they fall into the wrong hands.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/8QNQRhBstRg?wmode=transparent&start=28" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Scientists are studying how to print thin layers of thermite, a type of energetic material, onto surfaces.</span></figcaption>
</figure>
<p>Theoretically, you could also 3D-print these inks strategically onto old satellites or the <a href="https://www.cnn.com/2022/02/02/world/nasa-international-space-station-retire-iss-scn/index.html">aging International Space Station</a> to break up these orbiting devices into <a href="https://arc.aiaa.org/doi/10.2514/6.2024-2162">small enough debris</a> that burns up in the atmosphere before hitting the ground. </p>
<p>Many researchers are looking into 3D-printing gun propellants. <a href="https://doi.org/10.1002/prep.201900176">Modifying the shape of gun propellants</a> could make bullets that can fly farther. </p>
<p>Others have sought to use 3D printing to reduce the environmental impact of <a href="https://serdp-estcp.mil/projects/details/a04a6382-e4d4-4e7e-b262-2febb6cae014/wp19-1246-project-overview">gun propellants</a> and <a href="https://serdp-estcp.mil/projects/details/7a5dc45b-a30b-485f-93ab-ec3731356b3c/wp19-1300-project-overview">igniters that require harsh solvents</a> to manufacture. These solvents are unsafe, difficult to dispose of and can harm <a href="https://www.epd.gov.hk/epd/english/environmentinhk/air/prob_solutions/vocs_smog.html">the environment</a> and <a href="https://www.epa.gov/indoor-air-quality-iaq/volatile-organic-compounds-impact-indoor-air-quality">peoples’ health</a>. </p>
<p>I showed that it is possible to <a href="https://www.purdue.edu/newsroom/releases/2018/Q2/now-you-can-3d-print-clay,-cookie-dough--or-solid-rocket-fuel.html">3D-print solid rocket propellants</a> that have similar properties to traditionally made propellants. With that research, we now have the opportunity to explore how <a href="https://doi.org/10.2514/1.B38282">propellants made of multiple materials burn</a>, which is new territory. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/OIdLg4zeGso?wmode=transparent&start=2" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">To 3D-print rocket propellants, you first need to figure out how to print very viscous materials.</span></figcaption>
</figure>
<p>For example, instead of using a rod to made a cross-sectional shape in a propellant, you could <a href="https://doi.org/10.2514/1.B38128">3D-print a highly reactive material</a> that you could add to the center. Instead of having to remove that center material, you could burn it up so fast that it leaves a core shape behind. The reactive material would also add energy to the propellant. This would eliminate the need to use and remove a rod to make a central core.</p>
<p>While much of this research is in its infancy, companies such as <a href="https://www.prnewswire.com/news-releases/x-bow-systems-launches-second-successful-bolt-rocket-301851088.html">X-Bow</a> have been 3D-printing propellants and conducting successful flight tests with these motors.</p>
<p>Finally, several researchers have studied how <a href="https://www.machinedesign.com/3d-printing-cad/article/21836373/a-look-inside-the-explosive-3dprinting-industry">3D-printed explosives</a> detonate. When the explosives are printed into a grid-shaped lattice, they react differently when their pores are filled with air or water. This process produces a safer “<a href="https://discover.lanl.gov/news/0317-high-explosives/">switchable” explosive</a> that does not react unless it is in a specific environment. </p>
<p>3D-printing energetic materials is still a new field. Scientists have a long way to go before we completely understand how <a href="https://doi.org/10.1002/prep.202380231">3D printing affects their safety and performance</a>. But every day, scientists like me are finding new ways to use 3D-printed energetics to serve crucial, and sometimes lifesaving, purposes.</p><img src="https://counter.theconversation.com/content/214126/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Monique McClain receives funding from Air Force Office of Scientific Research (AFOSR), Army Research Office (ARO), and National Aeronautics and Space Administration (NASA).</span></em></p>‘Energetic’ materials are ones that readily ignite or detonate. The shapes of those materials have a big effect on how they burn or blow up.Monique McClain, Assistant Professor of Mechanical Engineering, Purdue UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2223072024-02-08T13:21:28Z2024-02-08T13:21:28ZA new generation of spaceplanes is taking advantage of the latest in technology<figure><img src="https://images.theconversation.com/files/572455/original/file-20240131-25-t35ou5.jpeg?ixlib=rb-1.1.0&rect=5%2C0%2C1911%2C1281&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Dream Chaser would ferry cargo, and eventually crew, to low-Earth orbit.</span> <span class="attribution"><a class="source" href="https://images.nasa.gov/details/AFRC2017-0124-015">Ken Ulbrich / NASA</a></span></figcaption></figure><p><a href="https://www.nasa.gov/space-shuttle/">Nasa’s space shuttle</a> operated in low-Earth orbit for 30 years before its retirement in 2011. However, the US space agency’s <a href="https://www.nasa.gov/humans-in-space/orion-spacecraft/">replacement for this vehicle, Orion</a>, returned to the conical capsule design familiar from the Apollo missions. This was because Nasa intended that this newer craft be used for exploring targets in deep space, such as the Moon.</p>
<p>But in recent years, we have seen a return of the spaceplane design. <a href="http://news.bbc.co.uk/1/hi/sci/tech/8601172.stm">Since 2010</a>, the US Space Force (and formerly the US Air Force) has been <a href="https://www.spaceforce.mil/News/Article-Display/Article/3628417/united-states-space-force-launches-seventh-x-37b-mission/#:%7E:text=KENNEDY%20SPACE%20CENTER%2C%20Fla.,Space%20Center%20Launch%20Complex%2039A.">launching a robotic spaceplane called the X-37B</a> into low Earth orbit on classified missions. China has its own <a href="https://www.space.com/china-space-plane-depoyed-mystery-objects">military spaceplane called Shenlong</a>. </p>
<p>This year could see a test flight of the company Sierra Space’s <a href="https://www.sierraspace.com/dream-chaser-spaceplane/">Dream Chaser</a> – the first commercial spaceplane capable of orbital flight. If all goes well, the vehicle could be used to resupply the International Space Station (ISS) with cargo and, eventually, crew. </p>
<p>Spaceplanes can fly or glide in the Earth’s atmosphere and land on runways rather than using parachutes to land in water or flat ground like capsules. They’re also more manoeuvrable as the spacecraft reenters the atmosphere, increasing the area of the Earth’s surface where landing is possible from a specific re-entry point. </p>
<p>Spaceplanes also allow a gentler but longer flight path during re-entry and a softer landing, which is easier on crew and cargo than capsules, which can land with a thump. A runway also allows ground support crews and infrastructure to be ready at the landing location.</p>
<h2>Cost and complexity</h2>
<p>But spaceplanes are more complex and heavier than an equivalent capsule. The winged body shape poses a particular challenge for designing thermal protection systems (TPS) – the heat-resistant materials that protect the craft from scorching temperatures on re-entry. These additional costs mean it’s impractical to design a spaceplane for a single flight. They need to be used again and again to be viable.</p>
<figure class="align-center ">
<img alt="X-37B." src="https://images.theconversation.com/files/572489/original/file-20240131-27-2o63f0.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/572489/original/file-20240131-27-2o63f0.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/572489/original/file-20240131-27-2o63f0.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/572489/original/file-20240131-27-2o63f0.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/572489/original/file-20240131-27-2o63f0.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/572489/original/file-20240131-27-2o63f0.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/572489/original/file-20240131-27-2o63f0.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The US Space Force’s X-37B carries no crew, and its missions are classified.</span>
<span class="attribution"><a class="source" href="https://www.spaceforce.mil/Multimedia/Photos/igphoto/2003113618/">Staff Sgt. Adam Shanks / US Space Force</a></span>
</figcaption>
</figure>
<p>There has been interest in spaceplanes from the earliest days of human spaceflight. A military spaceplane project called <a href="https://apps.dtic.mil/sti/citations/ADA303832">Dyna-Soar</a> was started in the US in 1957, then cancelled just after construction started. The vehicle was sophisticated for its time, built using a metal alloy that is able to withstand high temperatures and featuring a heat shield on the front that could be detached after it returned from space, so that the pilot could see clearly as he was landing.</p>
<p>The space shuttle, which entered service in 1981, was the first operational spaceplane. It was supposed to launch more often than it did and have <a href="https://www.popularmechanics.com/space/rockets/a36304153/nasa-space-shuttle/">greater reusability</a> but it turned out that extensive refurbishment was required between launches. It did, however, demonstrate the ability to return astronauts and large cargo from orbit.</p>
<p>Other space agencies invested in the 1980s and 1990s, in Europe, with <a href="https://www.esa.int/About_Us/ESA_history/History_Hermes_spaceplane_1987">the Hermes spaceplane</a>, and Japan, with <a href="https://www.flightglobal.com/japan-stops-work-on-hope-x-spaceplane-/33798.article">the HOPE vehicle</a>. Both programmes were cancelled in large part because of cost. The Soviet Union developed its own <a href="https://airandspace.si.edu/stories/editorial/soviet-buran-shuttle-one-flight-long-history">shuttle-like vehicle called Buran</a>, which successfully flew to space once in 1988. The programme was cancelled after the collapse of the Soviet Union.</p>
<h2>Feeling the heat</h2>
<p>Spaceplanes have specific requirements for the final part of their journeys – as they return from space. <a href="https://www.faa.gov/sites/faa.gov/files/about/office_org/headquarters_offices/avs/III.4.1.7_Returning_from_Space.pdf">During atmospheric re-entry</a>, they are heated to over one thousand degrees Celsius as they travel at hypersonic speeds of over seven kilometres per second – more than 20 times the speed of sound. A blunt nose design (where the edge of the spacecraft is rounded) is an ideal shape because it reduces build-up of heat at the foremost part of the vehicle.</p>
<figure class="align-center ">
<img alt="Space shuttle, STS-132" src="https://images.theconversation.com/files/573023/original/file-20240202-19-du1hll.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/573023/original/file-20240202-19-du1hll.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/573023/original/file-20240202-19-du1hll.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/573023/original/file-20240202-19-du1hll.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/573023/original/file-20240202-19-du1hll.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/573023/original/file-20240202-19-du1hll.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/573023/original/file-20240202-19-du1hll.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">On launch, the space shuttle was attached to the side of a large external propellant tank.</span>
<span class="attribution"><a class="source" href="https://images.nasa.gov/details/sts132-s-047">NASA / JSC</a></span>
</figcaption>
</figure>
<p>Even so, the expected temperatures experienced by the craft can still be as high as 1600°C, necessitating a thermal protection system on the outside of the vehicle. <a href="https://www.centennialofflight.net/essay/Evolution_of_Technology/TPS/Tech41.htm">The space shuttle TPS</a> included ceramic tiles that were especially heat resistant and a reinforced carbon-carbon matrix that was capable of withstanding temperatures as high as 2400°C. </p>
<p>The <a href="https://www.nasa.gov/history/20-years-ago-remembering-columbia-and-her-crew/">loss of the Columbia shuttle</a> during re-entry in 2003, causing the deaths of seven astronauts, was the result of a breach in the TPS on the leading edge of the wing. This resulted from a piece of insulating foam flying off the shuttle’s external tank during Columbia’s launch and hitting the wing. </p>
<p>This foam issue was recurrent with the shuttle because of the way it launched on the side of the external propellant tank. But newer spaceplane designs will fly atop conventional rockets, where falling foam isn’t a problem.</p>
<p>An effective TPS remains vital for the <a href="https://www.nasa.gov/wp-content/uploads/2016/08/2015_nasa_technology_roadmaps_ta_9_entry_descent_landing_final.pdf">future success of spaceplanes</a>, as are systems that monitor the TPS performance in real time.</p>
<h2>Current vehicles</h2>
<p>There are currently two operating spaceplanes, one Chinese and one American, that can reach orbit. Little information is available on China’s Shenlong, but <a href="https://www.boeing.com/defense/autonomous-systems/x37b">the US military’s X-37B</a> is better known. Weighing close to five tonnes at launch, the nine metre-long, uncrewed vehicle is launched using a conventional rocket and lands autonomously on a runway at the end of its mission. </p>
<p>The X-37B’s TPS uses tiles similar to the shuttle over the lower surface with a lower-cost alternative to reinforced <a href="https://en.wikipedia.org/wiki/Reinforced_carbon%E2%80%93carbon">carbon-carbon</a> called Tufroc, developed for the X37B, on the nose and leading edges.</p>
<p>They should soon be joined by Dream Chaser, which was was developed by the company to carry both cargo and astronauts, but Nasa wants to prove its safety before carrying people by using it to carry cargo to the space station first. The ability to return comparatively fragile cargo to the surface because of a softer landing is a key capability. The tiles that protect Dream Chaser are made from silica, and <a href="https://www.nasaspaceflight.com/2023/09/dream-chaser-tps/">each has a unique shape</a> matched to the area on the vehicle they are designed to protect.</p>
<figure class="align-center ">
<img alt="Dream Chaser" src="https://images.theconversation.com/files/573027/original/file-20240202-27-ml7rkh.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/573027/original/file-20240202-27-ml7rkh.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/573027/original/file-20240202-27-ml7rkh.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/573027/original/file-20240202-27-ml7rkh.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/573027/original/file-20240202-27-ml7rkh.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1130&fit=crop&dpr=1 754w, https://images.theconversation.com/files/573027/original/file-20240202-27-ml7rkh.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1130&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/573027/original/file-20240202-27-ml7rkh.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1130&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Dream Chaser undergoing evaluation at Nasa’s Neil Armstrong Test Facility.</span>
<span class="attribution"><a class="source" href="https://twitter.com/NASAglenn/status/1753108059004825754/photo/1">NASA</a></span>
</figcaption>
</figure>
<h2>Future developments</h2>
<p>There is continued interest in spaceplanes because of their ability to return crew and cargo to a runway. The demand for this capability is limited now. But if the costs of launching to space continue falling and an expansion of industry in space raises demand, they will become an increasingly viable alternative to capsules.</p>
<p>Longer term, there is also potential for spaceplanes capable of reaching orbit after taking off from a runway. The challenges of developing these single-stage-to-orbit (SSTO) vehicles is considerable. However, <a href="https://www.colorado.edu/faculty/kantha/sites/default/files/attached-files/70494-96876_-_kyle_borg_-_may_8_2015_853_am_-_borg_matula_skylon_report.pdf">concepts such as the Skylon vehicle</a> are leading to technical developments that could eventually support development of an SSTO craft.</p>
<p>For the foreseeable future, spaceplanes look promising for the following reasons: new design techniques, improved materials for the TPS, advanced computer modelling and simulation tools for optimising different aspects of design and flight parameters and continuous improvements in propulsion systems. </p>
<p>Given that several governments, space agencies, and private companies worldwide are investing heavily in spaceplane research and development, we could see a future where flights with these vehicles become routine.</p><img src="https://counter.theconversation.com/content/222307/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Spaceplanes seemed out of favour when the shuttle was retired in 2011; they now seem to be making a comeback.Oluwamayokun Adetoro, Senior Lecturer, Mechanical and Aerospace Engineering, Brunel University LondonJames Campbell, Reader, Brunel University LondonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2208182024-02-02T13:17:06Z2024-02-02T13:17:06ZHow can I get ice off my car? An engineer who studies airborne particles shares some quick and easy techniques<figure><img src="https://images.theconversation.com/files/572255/original/file-20240130-29-7n5wna.jpeg?ixlib=rb-1.1.0&rect=0%2C3%2C1024%2C763&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Condensation and cold combine to create that layer of ice on car windshields in winter. </span> <span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Oblodzone_szyby_samochodu,_zima_2009_%28ubt%29.jpeg">Tomasz Sienicki/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>If you live somewhere that gets cold in the winter, you’ve probably seen cars parked outdoors covered in a thin layer of ice on a chilly morning. But what causes this frost, and how can you get rid of it quickly?</p>
<p>I’m a <a href="https://scholar.google.com/citations?user=xcpTqRYAAAAJ&hl=en">mechanical engineering professor</a> who studies how water vapor interacts with airborne particles under different atmospheric conditions. Frosty windshields are similar to some of the thermodynamic questions I study in the lab, and they’re also a pesky issue that I deal with every winter on my way to work. </p>
<h2>Windshield condensation</h2>
<p>The air in Earth’s atmosphere always contains a certain amount of water vapor, but there’s only so much water vapor the air can hold. Scientists call that limit 100% <a href="https://www.britannica.com/science/humidity">relative humidity</a>. <a href="https://www.weather.gov/arx/why_dewpoint_vs_humidity">The dew point</a> refers to the temperature at which relative humidity reaches 100%. </p>
<p>Wet air has high dew point temperature, while dry air has a low dew point temperature. With each degree drop in temperature, the air gets closer to its dew point temperature – or its water vapor carrying capacity. Any cooling after the dew point temperature has been reached causes <a href="https://sealevel.jpl.nasa.gov/ocean-observation/understanding-climate/air-and-water/">water to condense onto surfaces</a>, or form into fog.</p>
<p>Overnight, car windshields facing the cold dark sky are <a href="https://www.energy.gov/energysaver/principles-heating-and-cooling">radiatively cooled</a>, meaning they release heat out into their surrounding area in the form of visible and invisible light. As air comes in contact with the cold windshield, it can reach its dew point temperature. Then, the water vapor condenses onto the windshield.</p>
<p>When this radiative cooling drops the temperature on the windshield’s surface to <a href="https://www.britannica.com/science/freezing-point">below the freezing point</a>, 32 degrees Fahrenheit (zero degrees Celsius), the layer of condensed water on the windshield turns to frost. </p>
<h2>Defrosting your car</h2>
<p>To defrost an icy windshield, you can follow a few different approaches, some of which take longer and require more effort than others.</p>
<p>One option is to directly spray a small amount of warm liquid on the layer of frost to help melt it. For this approach to work, the spray liquid must be hot enough to raise the overall temperature of the frost layer to above <a href="https://pubchem.ncbi.nlm.nih.gov/ptable/melting-point/">the melting point</a>. But the temperature can’t be way hotter than the temperature of the glass or you’ll crack your windshield. </p>
<p>A better way to melt the ice without damaging your car is to spray your windows with a warm liquid that has a lower freezing point than water, like a mixture of rubbing alcohol and water. This warm mixture will melt the frost layer without heating up the glass, and the resulting liquid layer on the windshield will have a lower freezing point than water. It will remain liquid, and you can wipe it away with your windshield wipers. </p>
<p>Similar alcohol and water mixtures – <a href="https://www.britannica.com/science/glycol">glycol, for example</a> – are commonly used to maintain the <a href="https://mayekawa.es/images/pdf/ASHRAE_ENERGY_EFFICIENT_ICE_RINK_2015.pdf">icy surface of skating rinks</a>.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/A2Kl04dHm4k?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">A mix of water and rubbing alcohol can melt ice on your windshield.</span></figcaption>
</figure>
<p>This approach can melt the ice reasonably quickly and easily, without too much effort. You don’t even have to turn on your car. </p>
<p>If you have a little more time, you can start the car and run <a href="https://www.lifewire.com/how-do-car-defrosters-work-534663">the air defrost system</a> to blow hot air – aim for above 80 degrees Fahrenheit – onto the inside of the windshield. This warms the windshield and will eventually melt the frost layer. Once you see some melting, you can use the windshield wipers to wipe the rest of the ice away. </p>
<p>This option consumes more energy, as your car will have to heat up the windshield, but it doesn’t require you to do much. </p>
<p>Using the defrost system to blow warm air toward the windshield will also help to clear the inside of the windshield when it gets fogged up from condensation. Otherwise, if it’s dry outside, you can also clear up windshield fog by opening the car window and letting in outside air.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/572257/original/file-20240130-23-r3f30r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A person wearing a winter jacket uses a scraper on their frost-covered windshield." src="https://images.theconversation.com/files/572257/original/file-20240130-23-r3f30r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/572257/original/file-20240130-23-r3f30r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=396&fit=crop&dpr=1 600w, https://images.theconversation.com/files/572257/original/file-20240130-23-r3f30r.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=396&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/572257/original/file-20240130-23-r3f30r.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=396&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/572257/original/file-20240130-23-r3f30r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=497&fit=crop&dpr=1 754w, https://images.theconversation.com/files/572257/original/file-20240130-23-r3f30r.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=497&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/572257/original/file-20240130-23-r3f30r.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=497&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">You can use an ice scraper to break the ice on your windshield into chunks, so your wiper blades can clean them off.</span>
<span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/ColoradoWeather/c8d71e03eb5144afad7c01e72eccf5c2/photo?Query=windshield%20wipers&mediaType=photo&sortBy=&dateRange=Anytime&totalCount=296&digitizationType=Digitized&currentItemNo=17&vs=true&vs=true">AP Photo/David Zalubowski</a></span>
</figcaption>
</figure>
<p>If you are in a hurry or need some exercise, you can use an ice scraper to break up frost on your windshield, creating smaller islands of ice. The windshield wiper can then mechanically dislodge the chunks by moving them around and melting them. This requires more energy on your part, but it doesn’t require much from your car.</p>
<p>If you have a relaxed start to your day, you can let the Sun warm the windshield and slowly melt the frost layer for you. This technique saves energy in every way imaginable.</p><img src="https://counter.theconversation.com/content/220818/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Suresh Dhaniyala does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>When you’re running late in the winter, you don’t want to have to spend time scraping frost off your windshield. Try some expert-recommended techniques instead.Suresh Dhaniyala, Bayard D. Clarkson Distinguished Professor of Mechanical and Aeronautical Engineering, Clarkson UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2114702024-01-24T13:29:42Z2024-01-24T13:29:42ZCombining two types of molecular boron nitride could create a hybrid material used in faster, more powerful electronics<figure><img src="https://images.theconversation.com/files/569648/original/file-20240116-15-csiabm.jpg?ixlib=rb-1.1.0&rect=8%2C17%2C5682%2C4471&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Hexagonal boron nitride, also known as 'white graphene.'</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/boron-nitride-monolayer-illustration-royalty-free-image/1161024204?phrase=boron+nitride&adppopup=true">Robert Brook/Science Photo Library via Getty Images</a></span></figcaption></figure><p>In chemistry, structure is everything. Compounds with the same chemical formula can have different properties depending on the arrangement of the molecules they’re made of. And compounds with a different chemical formula but a similar molecular arrangement can have similar properties.</p>
<p><a href="https://www.sciencedirect.com/topics/chemistry/graphene">Graphene</a> and a form of boron nitride called hexagonal boron nitride fall into the latter group. Graphene is made up of carbon atoms. Boron nitride, BN, is composed of boron and nitrogen atoms. While their chemical formulas differ, <a href="https://doi.org/10.1063/PT.3.3297">they have a similar structure</a> – so similar that many chemists call hexagonal boron nitride “white graphene.”</p>
<p>Carbon-based graphene has <a href="https://theconversation.com/graphene-is-a-proven-supermaterial-but-manufacturing-the-versatile-form-of-carbon-at-usable-scales-remains-a-challenge-194238">lots of useful properties</a>. It’s thin but strong, and it conducts heat and electricity very well, making it ideal for use in electronics.</p>
<p>Similarly, hexagonal boron nitride has a host of properties similar to graphene that could improve biomedical imaging and drug delivery, as well as computers, smartphones and LEDs. <a href="https://doi.org/10.1038/nmat2711">Researchers have studied</a> this type of boron nitride for many years.</p>
<p>But, hexagonal boron nitride isn’t the only useful form this compound comes in.</p>
<p>As <a href="https://scholar.google.com/citations?user=S5oLGEgAAAAJ&hl=en">materials engineers</a>, <a href="https://ajayan.rice.edu/">our research team</a> has been investigating another type of boron nitride called cubic boron nitride. We want to know if combining the properties of hexagonal boron nitride with cubic boron nitride could open the door to <a href="https://www.azom.com/article.aspx?ArticleID=78">even more useful applications</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/569649/original/file-20240116-15-c9h3ox.gif?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Molecular structures of molecules, with atoms represented as blue spheres and bonds represented by gray lines connecting them. The left structure is in the shape of the cube, the right in flat sheets of hexagons." src="https://images.theconversation.com/files/569649/original/file-20240116-15-c9h3ox.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/569649/original/file-20240116-15-c9h3ox.gif?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=227&fit=crop&dpr=1 600w, https://images.theconversation.com/files/569649/original/file-20240116-15-c9h3ox.gif?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=227&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/569649/original/file-20240116-15-c9h3ox.gif?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=227&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/569649/original/file-20240116-15-c9h3ox.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=285&fit=crop&dpr=1 754w, https://images.theconversation.com/files/569649/original/file-20240116-15-c9h3ox.gif?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=285&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/569649/original/file-20240116-15-c9h3ox.gif?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=285&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Cubic boron nitride, shown on the left, and hexagonal boron nitride, shown on the right.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Structures_cub_hex_BN.gif">Oddball/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-sa/4.0/">CC BY-NC-SA</a></span>
</figcaption>
</figure>
<h2>Hexagonal versus cubic</h2>
<p>Hexagonal boron nitride is, as you might guess, boron nitride molecules arranged in the shape of a flat hexagon. It looks honeycomb-shaped, like graphene. Cubic boron nitride has a <a href="https://www.azom.com/article.aspx?ArticleID=78">three-dimensional lattice structure</a> and looks like a diamond at the molecular level.</p>
<p>H-BN is thin, soft and used in cosmetics to give them a silky texture. It doesn’t melt or degrade even under extreme heat, which also makes it useful in electronics and other applications. Some scientists predict it could be used to build a <a href="https://doi.org/10.1016/j.cej.2020.127802">radiation shield</a> for spacecraft.</p>
<p>C-BN is hard and resistant. It’s used in manufacturing to make cutting tools and drills, and it can keep its sharp edge even at high temperatures. It can also help dissipate heat in electronics.</p>
<p>Even though h-BN and c-BN might seem different, when put together, <a href="https://doi.org/10.1021/acs.nanolett.3c01537">our research has found</a> they hold even more potential than either on its own.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/566921/original/file-20231220-23-komtmy.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Two white powders, the top labeled 'hexagonal boron nitride' and the bottom labeled 'cubic boron nitride' with a circle between them labeled 'mixed phase boron nitride.' The bottom powder is slightly more brown and more clumpy." src="https://images.theconversation.com/files/566921/original/file-20231220-23-komtmy.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/566921/original/file-20231220-23-komtmy.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=557&fit=crop&dpr=1 600w, https://images.theconversation.com/files/566921/original/file-20231220-23-komtmy.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=557&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/566921/original/file-20231220-23-komtmy.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=557&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/566921/original/file-20231220-23-komtmy.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=700&fit=crop&dpr=1 754w, https://images.theconversation.com/files/566921/original/file-20231220-23-komtmy.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=700&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/566921/original/file-20231220-23-komtmy.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=700&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The two forms of boron nitride have some similarities and some differences, but when combined, they can create a substance with a variety of scientific applications.</span>
<span class="attribution"><span class="source">Abhijit Biswas</span></span>
</figcaption>
</figure>
<p>Both types of boron nitride conduct heat and can provide electrical insulation, but one, h-BN, is soft, and the other, c-BN, is hard. So, we wanted to see if they could be used together to create materials with interesting properties.</p>
<p>For example, combining their different behaviors could make a coating material effective for high temperature structural applications. C-BN could provide strong adhesion to a surface, while h-BN’s lubricating properties could resist wear and tear. Both together would keep the material from overheating.</p>
<h2>Making boron nitride</h2>
<p>This class of materials doesn’t occur naturally, so scientists must make it in the lab. In general, high-quality c-BN has been difficult to synthesize, whereas h-BN is relatively easier to make as high-quality films, using what are called vapor phase deposition methods. </p>
<p>In vapor phase deposition, we heat up boron and nitrogen-containing materials until they evaporate. The evaporated molecules then get deposited onto a surface, cool down, bond together and form a thin film of BN.</p>
<p>Our research team has worked on combining h-BN and c-BN using <a href="https://doi.org/10.1021/nl1022139">similar processes</a> to vapor phase deposition, but we can also <a href="https://doi.org/10.1021/acs.nanolett.3c01537">mix powders of the two together</a>. The idea is to build a material with the right mix of h-BN and c-BN for thermal, mechanical and electronic properties that we can fine-tune.</p>
<p>Our team has found the composite substance made from combining both forms of BN together has a variety of potential applications. When you point a laser beam at the substance, it flashes brightly. Researchers could use this property to create display screens and improve radiation therapies in the medical field. </p>
<p>We’ve also found we can tailor how heat-conductive the composite material is. This means engineers could use this BN composite in <a href="https://doi.org/10.1021/acs.nanolett.3c01537">machines that manage heat</a>. The next step is trying to manufacture large plates made of a h-BN and c-BN composite. If done precisely, we can tailor the mechanical, thermal and optical properties to specific applications.</p>
<p>In electronics, h-BN could <a href="https://doi.org/10.1063/PT.3.3297">act as a dielectric – or insulator – alongside graphene</a> in certain, low-power electronics. As a dielectric, h-BN would help electronics operate efficiently and keep their charge. </p>
<p>C-BN could work alongside diamond to create <a href="https://www.nrel.gov/materials-science/wide-bandgap-semiconductors.html">ultrawide band gap materials</a> that allow electronic devices to work at a much higher power. Diamond and c-BN both conduct heat well, and together they could help cool down these <a href="https://doi.org/10.1002/aelm.201600501">high-power devices</a>, which generate lots of extra heat.</p>
<p>H-BN and c-BN separately could lead to electronics that perform exceptionally well in different contexts – together, they have a host of potential applications, as well. </p>
<p>Our BN composite could improve heat spreaders and insulators, and it could work in energy storage machines like supercapacitors, which are <a href="https://www.azonano.com/article.aspx?ArticleID=6643">fast-charging energy storage devices</a>, and rechargeable batteries.</p>
<p>We’ll continue <a href="https://www.preciseceramic.com/blog/boron-nitride-the-superhero-material-of-the-future.html">studying BN’s properties</a>, and how we can use it in lubricants, coatings and wear-resistant surfaces. Developing ways to scale up production will be key for <a href="https://www.linkedin.com/pulse/global-boron-nitride-market-2024-share-future-trends-d1uwf/?published=t">exploring its applications</a>, from materials science to electronics and even environmental science.</p><img src="https://counter.theconversation.com/content/211470/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Pulickel Ajayan receives funding from the Army Research Laboratory and the Army Research Office. </span></em></p><p class="fine-print"><em><span>Abhijit Biswas does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Two forms of the same boron nitride molecules couldn’t look and act more different – but combining them could lead to applications that have the best of both worlds.Pulickel Ajayan, Professor of Materials Science and NanoEngineering, Rice UniversityAbhijit Biswas, Research Scientist in Materials Science and Nanoengineering, Rice UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2180012024-01-12T13:28:40Z2024-01-12T13:28:40ZI wrote a play for children about integrating the arts into STEM fields − here’s what I learned about encouraging creative, interdisciplinary thinking<figure><img src="https://images.theconversation.com/files/562522/original/file-20231129-27-a3te04.jpeg?ixlib=rb-1.1.0&rect=18%2C18%2C4007%2C2999&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Scenes from 'The STEAM Plays,' performed in Michigan schools. </span> <span class="attribution"><span class="source">Thalia Lara</span></span></figcaption></figure><p>Often, science and art are described as starkly different things. That narrative can start early on, with kids encouraged to pursue a STEM – short for science, technology, engineering and math – education that may or may not include an arts education. </p>
<p>As a <a href="https://people.cal.msu.edu/roznows5/">professor of acting</a>, I’d never thought much about the STEM fields until I received a <a href="https://grad.msu.edu/news/steampower-facultystaff-fellows">fellowship to integrate the arts</a> into STEM educational models. I used the opportunity to write and direct a play for elementary schoolers that showed how the arts can improve upon and extend work in STEM fields when properly integrated – but it wasn’t an easy process. </p>
<h2>STEM or STEAM?</h2>
<p>Whether <a href="https://theconversation.com/explainer-whats-the-difference-between-stem-and-steam-95713">STEM should be augmented to STEAM</a> – science, technology, engineering, arts and math – with the <a href="https://doi.org/10.3390/educsci11070331">addition of the arts</a> remains <a href="https://www.washingtonpost.com/news/innovations/wp/2018/06/12/why-liberal-arts-and-the-humanities-are-as-important-as-engineering/">something of a debate</a>. </p>
<p>The origins of STEM education can be traced to as early as the <a href="https://www.archives.gov/milestone-documents/morrill-act">Morrill Act</a> of 1862, which promoted agricultural science and later engineering at land grant universities. In 2001, the National Science Foundation pushed a focus on STEM education in order to <a href="https://www.stemschool.com/articles/rich-history-of-stem-education-in-the-united-states">make the U.S. more competitive globally</a>. </p>
<p>A Biden-Harris initiative launched in December 2022 called <a href="https://www.ed.gov/news/press-releases/us-department-education-launches-new-initiative-enhance-stem-education-all-students">You Belong in STEM</a> offers support of more than US$120 billion for K-12 STEM education until the year 2025. But, starting in 2012, the United States Research Council has explored the idea of a <a href="https://www.frontiersin.org/articles/10.3389/feduc.2021.709560/">STEAM education</a>. </p>
<p>Researchers have found that when integrated into a STEM education, <a href="https://doi.org/10.1016/j.procs.2013.09.317">the arts make space for curiosity and innovation</a>. So why the lack of agreement and consistency around whether it should be STEM or STEAM? </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/GOYN70wszoo?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Lots of careers bridge both science and arts, from game design to photography and engineering.</span></figcaption>
</figure>
<p>The bias toward emphasizing a STEM education could be driven by the <a href="https://www.cnbc.com/2023/10/20/more-students-pursue-stem-degrees-because-of-high-paying-careers.html">higher future salaries</a> of STEM majors or the significant funding that is connected more to <a href="https://doi.org/10.1057/s41599-021-00891-x">STEM-based research</a> and grants than to the arts. A STEAM education takes more time and <a href="https://theconversation.com/improving-science-literacy-means-changing-science-education-178291">is more complex</a> than a traditional STEM educational model. </p>
<p>Or it could simply be that many academics in STEM fields lack the incentive for interdisciplinary work that brings in the arts, and vice versa. In fact, that was exactly the position I was in as an arts-based researcher asked to create something about STEM disciplines that I knew very little about.</p>
<h2>Putting on the play</h2>
<p>It took me several tries and lots of research to get the script of my STEAM-centered play to its current form. </p>
<p>At first, I made basic discoveries. I learned that <a href="https://www.invent.org/blog/trends-stem/stem-steam-defined">there is a debate</a> about whether the arts should be included in a STEM education. I learned that “<a href="https://stemeducationguide.com/is-psychology-stem/">soft sciences” like psychology</a> are <a href="https://doi.org/10.1007/s12124-020-09545-0">not included</a> in many STEM educational models. I lacked a background in most of the disciplines included in STEM. And I struggled to find a project that inspired me.</p>
<p>But eventually I began work on five one-act plays, called “The STEAM Plays: Using the Arts to Talk about STEM.” Each focused on a category of STEAM education. I wrote the first draft of the show with a chip on my shoulder, trying to prove that the arts did indeed belong in STEM education.</p>
<p>The tone was defensive and provocative – and not entirely appropriate for the elementary age range I was focused on. </p>
<p>The new, revised version that toured Michigan elementary schools in the Fall of 2023 contains 20 bite-sized comedic scenes and songs that dramatize how the arts are integral to many STEM fields. These include how engineering skills go into designing a celebrity’s evening gown, how bakers need to know some basic chemistry, and how the mathematical algorithms of TikTok find new videos for each user.</p>
<p>In each of the scenes, students can see how artistic imagination and creative thinking expand STEM education.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/563453/original/file-20231204-23-wjyepx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A group of people performing on a stage, wearing brightly colored costumes. The background is a screen projecting blue, green and yellow geometric shapes. The two performers on the left have their arms crossed and stand back to back, same on the right." src="https://images.theconversation.com/files/563453/original/file-20231204-23-wjyepx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/563453/original/file-20231204-23-wjyepx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/563453/original/file-20231204-23-wjyepx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/563453/original/file-20231204-23-wjyepx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/563453/original/file-20231204-23-wjyepx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/563453/original/file-20231204-23-wjyepx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/563453/original/file-20231204-23-wjyepx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">‘The STEAM Plays’ in action. Performers, from left: Alex Spevetz, Marcus Pennington, Zoe Dorst, Cassidy Williams and Olivia Hagar.</span>
<span class="attribution"><span class="source">Rob Roznowski</span></span>
</figcaption>
</figure>
<h2>Beyond the stage</h2>
<p>These themes emerge from a wider scholarly understanding that STEM isn’t done in a creativity vacuum, and <a href="https://doi.org/10.1016/j.procs.2013.09.317">stimulating students’ artistic thinking</a> will help them both in the science classroom and the art studio.</p>
<p>One plot point of the show is about an evil genius who views the arts as less important trying to keep the arts out of STEM. He swaps the bodies of a scientist and an actor, as well as an engineer and a creative writer. In each body swap, the STEM professional and the artist recognize how similar their work is. In the final scene, the evil genius tries to switch the bodies of Pythagoras and Taylor Swift, only to realize that music is all about math.</p>
<hr>
<figure class="align-right ">
<img alt="A square box with the words 'Art & Science Collide' and a drawing of a lightbulb with its wire filament in the shape of a brain, surrounded by a circle." src="https://images.theconversation.com/files/567788/original/file-20240103-23-yg479z.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/567788/original/file-20240103-23-yg479z.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/567788/original/file-20240103-23-yg479z.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/567788/original/file-20240103-23-yg479z.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/567788/original/file-20240103-23-yg479z.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/567788/original/file-20240103-23-yg479z.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/567788/original/file-20240103-23-yg479z.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Art & Science Collide series.</span>
</figcaption>
</figure>
<p><em><strong><a href="https://theconversation.com/us/topics/art-in-science-series-2024-149583">This article is part of Art & Science Collide</a></strong>, a series examining the intersections between art and science.</em></p>
<p><em>You may be interested in:</em></p>
<p><a href="https://theconversation.com/literature-inspired-my-medical-career-why-the-humanities-are-needed-in-health-care-217357">Literature inspired my medical career: Why the humanities are needed in health care</a></p>
<p><a href="https://theconversation.com/art-and-science-entwined-this-course-explores-the-long-interrelated-history-of-two-ways-of-seeing-the-world-210250">Art and science entwined: This course explores the long, interrelated history of two ways of seeing the world </a></p>
<p><a href="https://theconversation.com/art-illuminates-the-beauty-of-science-and-could-inspire-the-next-generation-of-scientists-young-and-old-168925">Art illuminates the beauty of science – and could inspire the next generation of scientists young and old</a> </p>
<hr>
<p>Many teachers have provided rave reviews. “The plays did an excellent job of highlighting the importance and value of arts in our educational system,” one noted. “Students walked away enjoying and having a deeper understanding of how all of the different aspects of STEAM were able to work together collaboratively.</p>
<p>A STEAM education in which <a href="https://www.ucf.edu/online/engineering/news/comparing-stem-vs-steam-why-the-arts-make-a-difference/">students learn soft skills</a> like empathy, collaboration, emotional intelligence and creativity through the arts helps prepare students for the job market. And these discussions aren’t confined only to K-12 education – many research grants <a href="https://new.nsf.gov/funding/learn/research-types/learn-about-interdisciplinary-research">encourage interdisciplinary work</a>.</p>
<p>My understanding of the STEM and STEAM debate and my experience writing, producing and watching how people respond to my show have helped me understand how the arts are necessary to every student’s education. I learned that without artistic imagination, STEM students’ big-picture thinking skills can get stifled. </p>
<p>It only took writing a play for children for me to get it myself.</p><img src="https://counter.theconversation.com/content/218001/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Rob Roznowski received funding from Michigan State University from two places. As part of the STEAMpower Fellowship <a href="https://grad.msu.edu/news/steampower-facultystaff-fellows">https://grad.msu.edu/news/steampower-facultystaff-fellows</a> $10,000
and the Humanities And Arts Grant Proposal System. <a href="https://research.msu.edu/humanities-and-arts-research-program">https://research.msu.edu/humanities-and-arts-research-program</a>
The first fellowship covered the writing and research. The HARPwas awarded to tour and design the play. $7000</span></em></p>Is it a STEM education or a STEAM education? Integrating arts into science programming and vice versa can pique kids’ curiosity − a play touring Michigan aims to do just that.Rob Roznowski, Professor of Acting, Michigan State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2197852024-01-11T13:24:53Z2024-01-11T13:24:53ZOtters, beavers and other semiaquatic mammals keep clean underwater, thanks to their flexible fur<figure><img src="https://images.theconversation.com/files/566392/original/file-20231218-18-2f1ege.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C2136%2C1467&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Otters and other semiaquatic mammals can keep clean even in dirty water. </span> <span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/ANIMALSINTROUBLE/88740e31a4f1471ea8048eda247fbceb/photo?Query=otter&mediaType=photo&sortBy=&dateRange=Anytime&totalCount=191&digitizationType=Digitized&currentItemNo=13&vs=true&vs=true">AP Photo/Kirsty Wigglesworth</a></span></figcaption></figure><p>Underwater surfaces can get grimy as they accumulate dirt, algae and bacteria, a process <a href="https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/biofouling">scientists call “fouling</a>.” But furry mammals like beavers and otters that spend most of their lives wet manage to avoid getting their fur slimy. These anti-fouling abilities come, in part, from one of fur’s unique properties — that each hair can bend and flex as an animal moves.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/_ev_ukj9HCU?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Fouling on boats and machinery can be a big problem, and scientists are searching for ways to prevent it.</span></figcaption>
</figure>
<p><a href="https://www.dickersonlab.com/">I’m a mechanical engineer</a> who studies fluid dynamics, or how liquids behave. My team recently <a href="https://doi.org/10.1098/rsif.2023.0485">published a study</a> showing that fur that was allowed to move back and forth in a flow of dirty water accumulated less than half the amount of dirt as fur that was <a href="https://doi.org/10.1098/rsif.2021.0904">held stiff from both ends</a>.</p>
<p>While lots of animals have <a href="https://theconversation.com/body-hair-helps-animals-stay-clean-and-could-inspire-self-cleaning-technologies-50445">fur that seems to clean itself</a>, semiaquatic mammals have the most grime-resistant, or “anti-fouling,” fur.</p>
<p>Our recent study compared fur fibers from beavers, otters, springbok, coyotes and more using a flow of water containing <a href="https://pubchem.ncbi.nlm.nih.gov/compound/Titanium-Dioxide">titanium dioxide</a>, a common additive in cosmetics. Titanium dioxide readily attaches to surfaces like skin. Our team pumped the dirty water over individual fibers in a closed loop for 24 hours, then cleaned the fibers to measure how much titanium dioxide they’d accumulated.</p>
<p>My colleagues and I then used mathematical techniques to combine all of fur’s properties into a single number that predicts its anti-fouling behavior. We considered each fur strand’s ability to bend, how fluid flows over it and other unique features of each species. </p>
<p><a href="https://doi.org/10.1098/rsif.2023.0485">We found</a> that the ability to flex was critical for keeping the animal’s fur clean. </p>
<h2>Why it matters</h2>
<p>Fouling can <a href="https://doi.org/10.1016/j.cis.2020.102336">damage the affected surface</a>. When fur fouls, the arrangement of individual strands across the animal’s pelt is disrupted, and the animal might struggle to stay warm or dry.</p>
<p><a href="http://dx.doi.org/10.3390/polym13060846">Industrial repellent methods</a> used to protect the bottom of ships and the insides of pipes often <a href="http://dx.doi.org/10.1016/j.marpolbul.2004.02.034">employ harmful chemicals</a> and consume energy and materials, unlike naturally evolved solutions.</p>
<p>Figuring out how fur stays clean naturally could lead to more environmentally friendly solutions for repelling fouling in the water supply, in marine environments and even in the medical field. Solutions could include surfaces with parts that can flex and move or that have little hairs on a surface. </p>
<p>Research into fur also reveals more about how these mammals have evolved to survive across a variety of environments.</p>
<h2>What still isn’t known</h2>
<p>Animal fur and the fouling process <a href="https://doi.org/10.1016/j.cis.2020.102336">are both complex</a>, so we still don’t fully understand how all the intricate properties of fur, from texture and length to cross-sectional shape and environmental conditions, contribute to cleanliness. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/566393/original/file-20231218-23-v903xy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A close-up of an otter's coat, with lots of brown fur packed closely together." src="https://images.theconversation.com/files/566393/original/file-20231218-23-v903xy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/566393/original/file-20231218-23-v903xy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/566393/original/file-20231218-23-v903xy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/566393/original/file-20231218-23-v903xy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/566393/original/file-20231218-23-v903xy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/566393/original/file-20231218-23-v903xy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/566393/original/file-20231218-23-v903xy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Since hairs in fur are packed densely, they brush against each other and don’t always move individually.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/otter-fur-close-up-royalty-free-image/691551942?phrase=fur%2Bup%2Bclose%2Botter">Hailshadow/iStock via Getty Images Plus</a></span>
</figcaption>
</figure>
<p>The strands of hair in fur don’t always move individually. On an animal, the hairs are packed tightly, and they likely clean each other by rubbing as their host moves. We can’t yet tell if rubbing and moving affect the host animal’s cleanliness. </p>
<h2>What’s next</h2>
<p>My colleagues and I have just scratched the surface of the mystery of furry mammal cleanliness, and there’s plenty more we can test. Future work could expose fur to biological foulers like bacteria and algae, or look at the role patches of fur play in cleanliness. </p>
<p>The only known mammal that does succumb to fouling is the sloth – <a href="https://news.mongabay.com/2014/03/sloths-moths-and-algae-a-surprising-partnership-sheds-light-on-a-mystery/">algae grows on their fur</a>. </p>
<p><em>The <a href="https://theconversation.com/us/topics/research-brief-83231">Research Brief</a> is a short take on interesting academic work.</em></p><img src="https://counter.theconversation.com/content/219785/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Andrew Dickerson receives funding from the National Science Foundation. </span></em></p>The bottoms of boats and docks can accumulate lots of dirt, but semiaquatic animals like otters avoid having ‘fouled’ fur. Their secret could one day help keep underwater infrastructure clean.Andrew Dickerson, Assistant Professor of Mechanical, Aerospace and Biomedical Engineering, University of TennesseeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2192602024-01-09T14:03:23Z2024-01-09T14:03:23ZStudying engineering is tough: 6 insights to help university students succeed<figure><img src="https://images.theconversation.com/files/565126/original/file-20231212-21-n9sczs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Support and a sense of community are among the ways that students build academic resilience.</span> <span class="attribution"><span class="source">ASphotowed/iStock/Getty Plus</span></span></figcaption></figure><p>Engineering courses are a <a href="https://www.news24.com/news24/bi-archive/what-popular-degrees-at-top-sa-universities-now-cost-with-some-degrees-varying-by-up-to-r30000-2023-1">popular</a> choice <a href="https://www.cambridgeinternational.org/news/news-details/view/85-per-cent-of-south-african-students-aspire-to-go-onto-university-and-follow-traditional-careers-according-to-new-global-research-20nov2018/">among</a> South African university students. But these courses are also gruelling and the attrition rates are high. The Council on Higher Education reports that half of the engineering students enrolled at South African universities <a href="https://www.timeslive.co.za/sunday-times/news/2018-05-26-joint-effort-needed-to-fix-university-dropout-rate/">do not complete their studies</a>. That figure <a href="https://nces.ed.gov/pubs2014/2014001rev.pdf">is similar</a> in other parts of the world.</p>
<p>Yet, some students weather the storms of an engineering degree with a remarkable resilience, ensuring not just survival but success. How do they do it? I am a senior lecturer and trained academic advisor, registered as a clinical psychologist, with a primary focus on well-being in the higher education sector. <a href="https://www.researchgate.net/publication/374925429_Academic_resilience_of_engineering_students_A_case_study">For my PhD</a> I examined engineering students’ experiences at one South African university to try to answer this question. </p>
<p>The study is particularly timely given the introduction, in 2017, of the <a href="https://www.researchgate.net/publication/372622522_Bachelor_of_Engineering_Technology_and_Diploma_students'_perceptions_of_success_influences_and_potential_retention">Bachelor of Engineering Technology (BEngTech) degree</a>. It replaced the National Diploma in Engineering. The BEngTech degree is more academically centred than its predecessor. It requires less practical in-service and work-integrated learning in industry, and is designed to better prepare students for postgraduate degrees in engineering. The shift is designed to raise academic standards and align South African qualifications with global benchmarks. This may make things even tougher for students.</p>
<p>My research delved into what’s known as academic resilience. With my supervisors, I defined this as accomplishing academic success in the face of academic challenges. Six key themes emerged. Understanding the dynamics of each theme will help universities to develop strategies for student support. This is especially crucial for courses with high drop-out rates like engineering. </p>
<h2>Key themes</h2>
<p>As my research took place during the COVID pandemic, all my interviews were conducted online. I interviewed 13 final-year engineering students, six lecturers and six support staff from one institution. A separate group of 66 final-year students participated in the study by completing a series of four standardised psychometric instruments.</p>
<p>Six key themes emerged.</p>
<p><strong>1. Personal character strengths and wellbeing.</strong> This theme emphasises the importance of internal qualities like hope, gratitude, spirituality, forgiveness, persistence, and perseverance. These are critical in overcoming academic challenges. For instance one participant, Lucien, told me he hoped to get a better job through further study. Another, Jack, was grateful for the effort he himself had put into his studies. </p>
<p>This finding challenges the traditional focus, in research about academic resilience, on <a href="https://link.springer.com/chapter/10.1007/978-1-4614-0586-3_2">socio-ecological</a> factors alone. It highlights the significance of individual character in forming resilience.</p>
<p><strong>2. Enabling vs constraining factors.</strong> This theme explores the dual nature of factors influencing academic resilience. On one hand, the ability to reflect, seek help and persevere enabled students to overcome academic challenges. This was evidenced by students attending additional support programmes and workshops. On the other, students faced adversities like adapting to new countries, language barriers and personal commitments which hindered their academic journey. </p>
<p>Students had a more positive outlook on their ability to grow and overcome challenges than staff did. This discrepancy in perceptions highlights the need for tailored support systems that acknowledge both the struggles and the strengths of students in their academic pursuits.</p>
<p><strong>3. Relational and socio-ecological support.</strong> The study showed that university-provided support, like curricular and extra-curricular workshops, reduced psychological distress and promoted a sense of belonging. But both students and staff thought that more personalised support was needed to cater to students’ unique circumstances and availability. Both groups recognised that the earlier appropriate and personalised support systems are introduced by the institution, the higher the likelihood of students’ academic resilience. Timely, tailored support is crucial in nurturing student success and resilience.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-lecturers-need-to-know-all-about-their-students-lives-fears-and-hopes-55580">Why lecturers need to know all about their students' lives, fears and hopes</a>
</strong>
</em>
</p>
<hr>
<p><strong>4. The transition to university.</strong> The transition to university, predominantly from school but with an increasing number from the working world, represents a critical period for developing resilience. Orientation programmes and support workshops were found to play a significant role in building resilience, especially for students new to the university environment. </p>
<p>I also found that younger students might adapt more easily than older students, suggesting a need for varied support approaches based on age groups. Moreover, students’ past experiences, such as previous work or educational transitions, contributed to a smoother adaptation to university life, emphasising the value of drawing on past experiences for future success.</p>
<p><strong>5. A sense of <a href="https://www.researchgate.net/publication/372622534_You_don%27t_necessarily_feel_like_you_belong_there_Understanding_belonging_and_social_connectedness_among_engineering_students_in_South_Africa">belonging</a> and social connection.</strong> This theme aligns with the African philosophy of <a href="https://www.youtube.com/watch?v=HED4h00xPPA">ubuntu</a>, emphasising <a href="https://www.researchgate.net/publication/344351024_You_Can't_Solve_a_Problem_Until_You_Ask_the_Right_Question_Positioning_Afrocentric_Learning_Communities_in_the_Post_FeesMustFall_Context">relational</a> resilience. </p>
<p>Students who felt a strong sense of belonging were more motivated and likely to succeed academically. It was clear that resilient students often forged empowering connections, helping them to overcome academic challenges. However, it’s important to note that the study may reflect a bias towards students who are adept at forming social bonds; further research may be needed to explore the experiences of those less skilled in this area.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/student-hunger-at-south-african-universities-needs-more-attention-123378">Student hunger at South African universities needs more attention</a>
</strong>
</em>
</p>
<hr>
<p><strong>6. <a href="https://www.researchgate.net/publication/366308508_I_would_help_the_lecturer_with_marking_Entrepreneurial_Education_Insights_on_Academic_Resilience_from_the_Perspectives_of_Engineering_Students_in_South_Africa">Assistance and resources</a></strong>: Access to adequate resources, including food support, specialised facilities and relational networks, is essential for student success. The study found that students utilising resources such as initiatives providing free daily meals to under resourced students showed better academic performance. This underscores the importance of addressing students’ basic needs. </p>
<h2>Real-world implications</h2>
<p>My hope is that these findings might guide institutions to better equip their students with the necessary tools to promote resilience. It’s important that such strategies acknowledge both the struggles and the strengths of students in their academic pursuits.</p><img src="https://counter.theconversation.com/content/219260/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Curwyn Mapaling received a PhD scholarship from the German Academic Exchange Service (DAAD) and the East and South African-German Centre of Excellence in Educational Research Methodologies and Management (CERM-ESA). </span></em></p>Understanding the dynamics of each theme from the research will help universities to develop strategies for student support.Curwyn Mapaling, Senior Lecturer, University of JohannesburgLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2168302023-11-08T23:08:26Z2023-11-08T23:08:26ZHidden tunnels, ambushes and explosives in walls: the Israel-Hamas war enters a precarious new phase<p>With Israeli Defence Forces now reportedly surrounding Gaza City, the most densely packed part of the Gaza Strip, their fight against Hamas has entered a new phase focused primarily on urban warfare – some of it underground.</p>
<p>Sappers are the soldiers who clear paths through obstacles with machines and explosives, enabling other troops to overwhelm the enemy. They also create such obstructions and lay traps and mines when trying to defend a position. </p>
<p>Tunnels are a sapper’s job, too. Indeed, this is where the word comes from: the ancient technique of “sapping” beneath the surface to approach an enemy position protected from their arrows, bullets or shells.</p>
<p>As part of their <a href="https://mwi.usma.edu/defending-the-city-an-overview-of-defensive-tactics-from-the-modern-history-of-urban-warfare/">plan</a> for defence, Hamas sappers have excavated a huge series of <a href="https://mwi.westpoint.edu/underground-nightmare-hamas-tunnels-and-the-wicked-problem-facing-the-idf/">tactical tunnels</a>. Some are interlinked, some isolated. Some have been dug far below where bombs can reach, some are near the surface to allow access. </p>
<p>Tunnels and “mouseholes” in walls also allow for undetected movement between buildings. <a href="https://www.ft.com/content/913d366e-0ace-4463-a004-d293aa49c673">Hamas fighters expect</a> they can emerge from these holes to attack Israeli soldiers before disappearing again. </p>
<p>In addition, Hamas sappers have likely prepared many improvised explosive devices (IEDs) – some hidden in walls to detonate when <a href="https://cat-uxo.com/explosive-hazards/ied/explosively-formed-projectile-efp">armoured vehicles pass by</a> and other, larger explosives buried under roads. </p>
<p>Some tunnels may also be set as traps to entice Israeli soldiers to enter as they search for hostages.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1720248174823063648"}"></div></p>
<h2>Urban warfare is excruciatingly slow</h2>
<p>As the war enters a new phase, it is pitting a grimly determined Israeli Defence Force (IDF), with the world’s <a href="https://www.timesofisrael.com/mini-gaza-the-idfs-urban-warfare-training-center-a-town-thats-known-only-war/">best</a> capabilities for urban warfare, against a force ready for martyrdom that has prepared for this fight for years. It will also be happening on terrain that analysts <a href="https://mwi.usma.edu/city-not-neutral-urban-warfare-hard/">argue</a> greatly favours the defender.</p>
<p>Though fighting in Gaza presents its own unique challenges, there are some lessons to be learned from the operations to eliminate Islamist fighters from the Iraqi city of Mosul and the southern Philippines city of Marawi in 2016-17. </p>
<p>In <a href="https://mwi.westpoint.edu/urban-warfare-project-case-study-2-battle-of-mosul/">Mosul</a>, a US-supported Iraqi force of about 100,000 took nine months to destroy an ISIS force of thousands in a thoroughly fortified city. The coalition lost <a href="https://www.ft.com/content/32bc687b-1385-401b-a60a-7320848ceb16">8,000 troops</a> and many tanks and <a href="https://www.washingtonpost.com/world/middle_east/bulldozers-have-become-more-crucial--and-more-vulnerable--in-the-fight-against-the-islamic-state/2017/05/29/0e6caf3a-409a-11e7-b29f-f40ffced2ddb_story.html">bulldozers</a> to massive IEDs. </p>
<p>Progress was equally slow in <a href="https://www.aspi.org.au/report/marawi-crisis-urban-conflict-and-information-operations">Marawi</a>, where it took five months for Filipino forces to defeat ISIS-Maute fighters. Troops could sometimes secure only one building per day because of the constant threat of ambush from tunnels and IEDs hidden in entrances, windows and stairwells.</p>
<h2>Three layers of challenges</h2>
<p>Urban war presents armies with compounding challenges. </p>
<p>The <a href="https://groundedcuriosity.com/unpacking-the-urban-fight-introducing-the-twelve-challenges-part-i-of-a-series/">first layer</a> is perceptual. There is a cognitive dissonance between a liberal society’s beliefs around the need for restraint in conflict and the primordial demands of urban war with its high costs in blood, destruction and legitimacy. Armies are averse to preparing for such horror. </p>
<p>Second, there are tactical challenges with fighting among buildings: </p>
<ul>
<li><p>the threat of remote attack by drones or IEDs </p></li>
<li><p>the uncertainty created by hidden adversaries </p></li>
<li><p>the extreme exposure of forces as they advance</p></li>
<li><p>the dilution of combat power as forces are channelled, isolated and dispersed among buildings, with very restricted views</p></li>
<li><p>the degrading of sensors and communications systems. </p></li>
</ul>
<p>Third, and critically, the <a href="https://www.icrc.org/en/what-we-do/war-in-cities">presence of civilians</a> in urban war zones imposes moral and ethical challenges. They suffer <a href="https://www.icrc.org/en/document/new-research-shows-urban-warfare-eight-times-more-deadly-civilians-syria-iraq">disproportionately and catastrophically</a>, both as immediate casualties and from displacement and disease following the destruction of cities. </p>
<p>Military commanders also face a proportionality <a href="https://www.e-ir.info/2022/05/27/the-lawful-killing-of-civilians-under-international-humanitarian-law/">dilemma</a> when it comes to <a href="https://www.justsecurity.org/56087/ambiguity-conduct-hostilities/">interpreting</a> international humanitarian law. They need to balance the necessity of their actions and the survival of soldiers against causing unintended but foreseeable civilian harm.</p>
<p>Further complexities include:</p>
<ul>
<li><p>the obligation of forces to provide security and logistical support to noncombatants</p></li>
<li><p>the security threat from phone and social media usage by civilians</p></li>
<li><p>civilians who are hostile, obstructive or offer unarmed resistance</p></li>
<li><p>the psychological and political burden on commanders that may distort their decision-making. </p></li>
</ul>
<h2>How Israel has been preparing for this moment</h2>
<p>The IDF has previously experienced these challenges in Gaza. After Israeli occupation ended in 2005, militant attacks prompted major incursions by the army in 2008 and 2014. That fighting taught the IDF key <a href="https://www.rand.org/content/dam/rand/pubs/research_briefs/RB9900/RB9975/RAND_RB9975.pdf">lessons</a>. </p>
<p>From a political standpoint, Israel realised the importance of winning the contest of international and domestic public opinion. From a military and operational standpoint, the IDF learned that precision air power alone could not eliminate the threat from Hamas. Well-protected armoured vehicles were essential, and new capabilities were needed to counter the increasing use of tunnels by Hamas. </p>
<p>As a result, the IDF is uniquely well-equipped for urban operations, with the world’s best-protected tanks and <a href="https://www.forbes.com/sites/davidaxe/2023/10/13/israels-namer-is-the-heaviest-best-protected-armored-personnel-carrier-in-the-world-hamas-just-captured-one/?sh=1585941a5271">armoured personnel carriers</a>. </p>
<p>It also has world-leading armoured engineering vehicles, such as the <a href="https://www.armyrecognition.com/defense_news_july_2023_global_security_army_industry/israel_defense_force_uses_armored_caterpillar_d9_bulldozers_to_destroy_ieds_in_palestinan_camp_of_jenin.html">D9 armoured “Doobi” bulldozer</a>. With the D9, houses can be demolished instead of entered, reducing the risk of ambush and IEDs. However, these bulldozers have been controversially associated with destroying homes as punishment. </p>
<p>The D9 will be used in the war to create safe paths through terrain that may be mined, push alternative routes through buildings and build protective berms around “secured areas” to consolidate the IDF’s progress. Some of these bulldozers can even be operated by remote control.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/558224/original/file-20231108-29-lujaxp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/558224/original/file-20231108-29-lujaxp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=463&fit=crop&dpr=1 600w, https://images.theconversation.com/files/558224/original/file-20231108-29-lujaxp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=463&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/558224/original/file-20231108-29-lujaxp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=463&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/558224/original/file-20231108-29-lujaxp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=582&fit=crop&dpr=1 754w, https://images.theconversation.com/files/558224/original/file-20231108-29-lujaxp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=582&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/558224/original/file-20231108-29-lujaxp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=582&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The IDF’s Caterpillar D9R armoured bulldozer.</span>
<span class="attribution"><span class="source">Zachi Evenor/Wikimedia Commons</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Other armoured engineering vehicles include the <a href="https://www.militarytoday.com/engineering/puma.htm">Puma minefield breacher</a>, with the <a href="https://www.rafael.co.il/wp-content/uploads/2019/03/Carpet.pdf">Carpet</a> mine and IED clearing system that can detonate or disrupt hidden munitions with blasts from
fuel-air explosive rockets. Engineer vehicles also carry equipment that can jam IED circuits or transmissions. Some may also have the <a href="https://www.ynetnews.com/articles/0,7340,L-5170565,00.html#:%7E:text=The%20IDF%20chose%20to%20make%20relatively%20rare%20use,the%20border%20of%20the%20Gaza%20Strip%20last%20December.">THOR</a> system, which uses lasers to explode IEDs.</p>
<p>Soldiers are also trained to find, operate in and destroy tunnels. They include elements of the <a href="https://www.idf.il/en/mini-sites/the-hamas-terrorist-organization/this-is-the-idf-s-plan-to-combat-hamas-terror-tunnels/">Sarayet Yahalom</a>, a special forces unit that uses specialised demolition charges, subterranean drones and robots. </p>
<p>The Israelis lead the world in highly classified <a href="https://www.israelandstuff.com/israeli-team-who-developed-terror-tunnel-detection-system-wins-defense-prize">subterranean sensing research</a>, including the use of geospatial, acoustic, seismic, electrical resistivity tomography (ERT) and ground-penetrating radar technologies. The IDF’s public statements suggest tunnels within 20 metres of the surface can be mapped. </p>
<p>The IDF tunnel sappers also have <a href="https://aw.my.games/en/news/general/heavy-apcs-centurion-variants">niche armoured fighting vehicles</a>. Some are fitted with the technologies mentioned above, others with drilling equipment that can bore down into tunnels to deliver devices, materials or explosives. One, the Nakpilon, uniquely has a door at the front to deploy soldiers straight into tunnel entrances. </p>
<p>The IDF has generally preferred to destroy tunnels from the surface rather than entering, but some Yahalom and other <a href="https://www.isayeret.com/">reconnaissance special forces</a> train to fight below ground, alongside the Oketz dog unit, with specialised vision, breathing and communications equipment. </p>
<p>Given the scale of the tunnel network and the task of recovering hostages, some human reconnaissance seems unavoidable. <a href="https://historycollection.com/10-crazy-things-never-knew-tunnel-rat-soldiers-vietnam-war/3/">History suggests</a> this will be done by pairs or individuals, perhaps the <a href="https://www.jewishvirtuallibrary.org/the-mista-arvim">Mista’arvim elite undercover units</a>, who may operate by disguising themselves as Hamas fighters. </p>
<p>Given the Hamas advantage of home terrain and the advanced technology deployed by Israel, both sides will likely inflict bloody surprises on one another. The IDF has the military capability to prevail, but the human cost of the ground war and the outcome of the crucial geopolitical war of narratives remain unclear.</p><img src="https://counter.theconversation.com/content/216830/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Charles Knight does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Though Hamas has the advantage of fighting on its territory, Israel has developed one of the most effective urban fighting militaries in the world.Charles Knight, Adjunct Lecturer in Terrorism and Assymetric Conflict and Senior Researcher in Urban Warfare (UNSW), Charles Sturt UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2171472023-11-07T13:36:33Z2023-11-07T13:36:33ZAcapulco was built to withstand earthquakes, but not Hurricane Otis’ destructive winds – how building codes failed this resort city<figure><img src="https://images.theconversation.com/files/557873/original/file-20231106-267225-w11vn6.jpg?ixlib=rb-1.1.0&rect=0%2C16%2C3593%2C2246&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Acapulco's beachfront condo towers were devastated by Hurricane Otis.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/aerial-view-of-damages-caused-by-the-passage-of-hurricane-news-photo/1750791993">Rodrigo Oropeza/AFP via Getty Images</a></span></figcaption></figure><p>Acapulco wasn’t prepared when Hurricane Otis struck as a powerful Category 5 storm on Oct. 25, 2023. The short notice as the <a href="https://www.nesdis.noaa.gov/news/hurricane-otis-causes-catastrophic-damage-acapulco-mexico">storm rapidly intensified</a> over the Pacific Ocean wasn’t the only problem – the Mexican resort city’s buildings weren’t designed to handle anything close to Otis’ 165 mph winds.</p>
<p>While Acapulco’s oceanfront high-rises were built to withstand <a href="https://www.reuters.com/world/americas/strong-quake-rocks-mexicos-acapulco-damaging-airport-killing-one-2021-09-08/">the region’s powerful earthquakes</a>, they had a weakness. </p>
<p>Since powerful hurricanes are <a href="https://coast.noaa.gov/hurricanes">rare in Acapulco</a>, Mexico’s <a href="https://www.gob.mx/cms/uploads/attachment/file/247555/300617_EvaluacionEstructuras_02-Viento.pdf">building codes didn’t require</a> that their exterior materials be able to hold up to extreme winds. In fact, those materials were often kept light to help meet earthquake building standards.</p>
<p>Otis’ powerful winds ripped off exterior cladding and shattered windows, exposing bedrooms and offices to the wind and rain. The storm <a href="https://www.pbs.org/newshour/world/death-toll-from-hurricane-otis-hits-48-with-36-missing-as-search-and-recovery-continues">took dozens of lives</a> and caused <a href="https://www.reinsurancene.ws/corelogic-pegs-hurricane-otis-insurable-loss-at-10bn-to-15bn/">billions of dollars in damage</a>.</p>
<figure class="align-center ">
<img alt="A large glass tower with sloping sides, like a sliced egg, reflects the sunrise with the Pacific Ocean looking placid in the background." src="https://images.theconversation.com/files/557814/original/file-20231106-17-xzhpml.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/557814/original/file-20231106-17-xzhpml.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=397&fit=crop&dpr=1 600w, https://images.theconversation.com/files/557814/original/file-20231106-17-xzhpml.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=397&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/557814/original/file-20231106-17-xzhpml.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=397&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/557814/original/file-20231106-17-xzhpml.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=498&fit=crop&dpr=1 754w, https://images.theconversation.com/files/557814/original/file-20231106-17-xzhpml.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=498&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/557814/original/file-20231106-17-xzhpml.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=498&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A US$130 million luxury condo building on the beach in Acapulco before Hurricane Otis struck on Oct. 25, 2023.</span>
<span class="attribution"><span class="source">Hamid Arabzadeh, PhD., P.Eng.</span></span>
</figcaption>
</figure>
<figure class="align-center ">
<img alt="A stormy sky shows through the floors that were once apartments." src="https://images.theconversation.com/files/557815/original/file-20231106-19-vbqly2.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/557815/original/file-20231106-19-vbqly2.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/557815/original/file-20231106-19-vbqly2.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/557815/original/file-20231106-19-vbqly2.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/557815/original/file-20231106-19-vbqly2.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/557815/original/file-20231106-19-vbqly2.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/557815/original/file-20231106-19-vbqly2.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The same Acapulco condo tower after Hurricane Otis.</span>
<span class="attribution"><span class="source">Hamid Arabzadeh, PhD., P.Eng.</span></span>
</figcaption>
</figure>
<p>I have worked on engineering strategies to enhance disaster resilience for over three decades and recently wrote a book, “<a href="https://rowman.com/ISBN/9781633888234/The-Blessings-of-Disaster-The-Lessons-That-Catastrophes-Teach-Us-and-Why-Our-Future-Depends-on-It">The Blessings of Disaster</a>,” about the gambles humans take with disaster risk and how to increase resilience. Otis provided a powerful example of one such gamble that exists when building codes rely on probabilities that certain hazards will occur based on recorded history, rather than considering the severe consequences of storms that can devastate entire cities.</p>
<h2>The fatal flaw in building codes</h2>
<p>Building codes typically provide “<a href="https://asce7hazardtool.online/">probabilistic-based” maps</a> that specify wind speeds that engineers must consider when designing buildings. </p>
<p>The problem with that approach lies in the fact that “probabilities” are simply the odds that extreme events of a certain size will occur in the future, mostly calculated based on past occurrences. Some models may include additional considerations, but these are still typically anchored in known experience. </p>
<p>This is all good science. Nobody argues with that. It allows engineers to design structures in accordance with a consensus on what are deemed acceptable <a href="https://doi.org/10.5194/nhess-19-1347-2019">return periods</a> for various hazards, referring to the likelihood of those disasters occurring. Return periods are a somewhat arbitrary assessment of what is a reasonable balance between minimizing risk and keeping building costs reasonable.</p>
<p>However, <a href="https://www.structuremag.org/?p=13360">probabilistic maps</a> only capture the odds of the hazard occurring. A <a href="https://hazards.atcouncil.org/">probabilistic map</a> might specify a wind speed to consider for design, irrespective of whether that given location is a small town with a few hotels or a megapolis with high-rises and complex urban infrastructure. In other words, probabilistic maps do not consider the consequences when an extreme hazard exceeds the specified value and “all hell breaks loose.”</p>
<h2>How probability left Acapulco exposed</h2>
<p>According to the Mexican building code, hotels, condos and other commercial and office buildings in Acapulco must be <a href="https://www.gob.mx/cms/uploads/attachment/file/247555/300617_EvaluacionEstructuras_02-Viento.pdf">designed to resist 88 mph winds</a>, corresponding to the strongest wind likely to occur on average once every 50 years there. That’s a Category 1 storm.</p>
<p>A 200-year return period for wind is used for essential facilities, such as hospital and school buildings, <a href="https://www.gob.mx/cms/uploads/attachment/file/247555/300617_EvaluacionEstructuras_02-Viento.pdf">corresponding to 118 mph winds</a>. But over a building’s life span of, say, 50 years, that still leaves a 22% chance that winds exceeding 118 mph will occur (yes, the world of statistics is that sneaky). </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/557871/original/file-20231106-15-ffcd7l.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A map of the Mexico area with lots of storm tracks offshore and a few crossing land in the southern part of the country." src="https://images.theconversation.com/files/557871/original/file-20231106-15-ffcd7l.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/557871/original/file-20231106-15-ffcd7l.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=457&fit=crop&dpr=1 600w, https://images.theconversation.com/files/557871/original/file-20231106-15-ffcd7l.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=457&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/557871/original/file-20231106-15-ffcd7l.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=457&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/557871/original/file-20231106-15-ffcd7l.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=575&fit=crop&dpr=1 754w, https://images.theconversation.com/files/557871/original/file-20231106-15-ffcd7l.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=575&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/557871/original/file-20231106-15-ffcd7l.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=575&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Mexico’s hurricane history in storm tracks.</span>
<span class="attribution"><a class="source" href="https://coast.noaa.gov/hurricanes/#map">NOAA</a></span>
</figcaption>
</figure>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/557869/original/file-20231106-19-jxgqql.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A map of the Acapulco area with lots of storm tracks offshore and a few crossing land." src="https://images.theconversation.com/files/557869/original/file-20231106-19-jxgqql.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/557869/original/file-20231106-19-jxgqql.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=427&fit=crop&dpr=1 600w, https://images.theconversation.com/files/557869/original/file-20231106-19-jxgqql.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=427&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/557869/original/file-20231106-19-jxgqql.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=427&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/557869/original/file-20231106-19-jxgqql.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=537&fit=crop&dpr=1 754w, https://images.theconversation.com/files/557869/original/file-20231106-19-jxgqql.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=537&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/557869/original/file-20231106-19-jxgqql.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=537&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A century of hurricane storm tracks near Acapulco show several offshore storms that brought strong winds and rain to the city, but few direct landfalls. Acapulco Bay is in the center of the map on the coast. Red, pink and purple lines are categories 3, 4 and 5, respectively.</span>
<span class="attribution"><a class="source" href="https://coast.noaa.gov/hurricanes/#map">NOAA</a></span>
</figcaption>
</figure>
<p>The probability wind maps for both return periods show Acapulco experiences lower average wind speeds than much of the 400 miles of Mexican coast north of the city. Yet, Acapulco is a major city, with a metropolitan population of over 1 million. It also has <a href="https://skyscraperpage.com/cities/?cityID=586&offset=100&statusID=1">more than 50 buildings</a> taller than 20 stories, according to the SkyscraperPage, a database of skyscrapers, and it is the only city with buildings that tall along that stretch of the Pacific coast.</p>
<p>Designing for a 50-year return period in this case is questionable, as it implies a near 100% chance of encountering wind exceeding this design value for a building with a 50-year life span or greater. </p>
<h2>Florida faces similiar challenges</h2>
<p>The shortcomings of probabilistic-based maps that specify wind speeds have also been observed in the United States. For example, new buildings along most of Florida’s coast must be able to <a href="https://www.flrules.org/gateway/readRefFile.asp?refId=13160&filename=Florida_Building_Code_7thEdition_1609_3_Tables.pdf">resist 140 mph winds</a> or greater, but there are a few exceptions. One is the Big Bend area where <a href="https://www.tampabay.com/hurricane/2023/09/02/map-idalia-flooding-big-bend-surge/">Hurricane Idalia made landfall</a> in 2023. Its design wind speed is about 120 mph instead.</p>
<p>A <a href="https://codes.iccsafe.org/content/FLBC2023P1/chapter-16-structural-design#FLBC2023P1_Ch16_Sec1609">2023 update to the Florida Building Code</a> raised the minimum wind speed to approximately 140 mph in Mexico Beach, the Panhandle town that was <a href="https://mexicobeachfl.gov/uploads/2022/06/Wind-load-Ordinance-21919.pdf">devastated by Hurricane Michael</a> in 2018. The Big Bend exception may be the next one to be eliminated.</p>
<h2>Acapulco’s earthquake design weakness</h2>
<p>A saving grace for Acapulco is that it is located in one of <a href="https://mexicodailypost.com/2021/04/19/earthquake-map-30-of-mexico-under-high-seismic-risk/">Mexico’s most active seismic risk zones</a> – for example, a <a href="https://www.nytimes.com/live/2021/09/07/world/mexico-earthquake">magnitude 7 earthquake struck nearby in 2021</a>. As a result, the lateral-load-resisting structural systems in tall buildings there are designed to resist seismic forces that are generally larger than hurricane forces.</p>
<p>However, a drawback is that the larger the mass of a building, <a href="https://www.wbdg.org/resources/seismic-design-principles">the larger the seismic forces</a> the building must be designed to resist. Consequently, light materials were typically used for the cladding – the exterior surface of the building that protects it against the weather – because that translates into lower seismic forces. This light cladding was not able to withstand hurricane-force winds.</p>
<p>Had the cladding not failed, the full wind forces would have been transferred to the structural system, and the buildings would have survived with little or no damage.</p>
<h2>A ‘good engineering approach’ to hazards</h2>
<p>A better building code could go one step beyond “good science” probabilistic maps and adopt a “<a href="https://michelbruneau.com/TheBlessingsOfDisaster.htm">good engineering approach</a>” by taking stock of the consequences of extreme events occurring, not just the odds that they will.</p>
<p>In Florida, the incremental cost of designing for wind speeds of 140 mph rather than 120 mph is marginal compared to total building cost, given that cladding able to resist more than 140 mph is already used in nearly all of the state. In Acapulco, with the spine of buildings already able to resist earthquake forces much larger than hurricane forces, designing cladding that can withstand stronger hurricane-level forces is likely to be an even smaller percentage of total project cost.</p>
<p>Someday, the way that design codes deal with extreme events such as hurricanes, not only in Mexico, will hopefully evolve to more broadly account for what is at risk at the urban scale. Unfortunately, as I explain in “<a href="https://michelbruneau.com/TheBlessingsOfDisaster.htm">The Blessings of Disaster</a>,” we will see more extreme disasters before society truly becomes disaster resilient.</p><img src="https://counter.theconversation.com/content/217147/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michel Bruneau does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>The best science is not always the best engineering when it comes to building codes. It’s also a problem across the US, as an engineer who works on disaster resilience explains.Michel Bruneau, Professor of Engineering, University at BuffaloLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2156522023-10-19T19:24:01Z2023-10-19T19:24:01ZNew class of recyclable polymer materials could one day help reduce single-use plastic waste<figure><img src="https://images.theconversation.com/files/554111/original/file-20231016-23-gcf4fp.jpg?ixlib=rb-1.1.0&rect=79%2C3%2C2038%2C1397&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Single-use plastics. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/various-types-of-plastic-trash-on-the-grass-plastic-royalty-free-image/1325351577?phrase=plastic&adppopup=true">Anton Petrus/Moment</a></span></figcaption></figure><p><a href="https://www.unep.org/interactives/beat-plastic-pollution/">Hundreds of millions of tons</a> of single-use plastic ends up in landfills every year, and even the small percentage of plastic that gets recycled can’t last forever. But our group of materials scientists has developed a new method for creating and deconstructing polymers that could lead to more easily recycled plastics – ones that don’t require you to carefully sort out all your recycling on trash day. </p>
<p>In the century since their conception, people have come to understand the enormous impacts – beneficial as well as detrimental – plastics have on human lives and the environment. As a <a href="https://miyakelab.colostate.edu/">group of polymer scientists</a> dedicated to inventing sustainable solutions for real-world problems, we set out to tackle this issue by rethinking the way polymers are designed and making plastics with recyclability built right in. </p>
<h2>Why use plastics, anyway?</h2>
<p>Everyday items including milk jugs, grocery bags, takeout containers and even ropes are made from a class of <a href="https://www.polymersolutions.com/blog/top-types-of-polyolefins-the-most-common-kind-of-plastics/">polymers called polyolefins</a>. Polyolefins make up around <a href="https://ourworldindata.org/grapher/plastic-waste-polymer">half of the plastics</a> produced and disposed of every year. </p>
<p>These polymers are used in plastics commonly labeled as HDPE, LLDPE or PP, or by their recycling codes #2, #4 and #5, respectively. These plastics are incredibly durable because the <a href="https://doi.org/10.1021/acssuschemeng.9b06635">chemical bonds</a> that make them up are extremely stable. But in a world set up for single-use consumption, this is no longer a design feature but rather a design flaw. </p>
<p><iframe id="2k7dQ" class="tc-infographic-datawrapper" src="https://datawrapper.dwcdn.net/2k7dQ/1/" height="400px" width="100%" style="border: none" frameborder="0"></iframe></p>
<p>Imagine if half of the plastics used today were recyclable by twice as many processes as they are now. While that wouldn’t get the recycling rate to 100%, a jump from single digits – <a href="https://www.energy.gov/articles/department-energy-releases-plastics-innovation-challenge-draft-roadmap-and-request">currently around 9%</a> – to double digits would make a big dent in the plastics produced, the plastics accumulated in the environment and their capacity for recycling and reuse. </p>
<h2>Recycling methods we already have</h2>
<p>Even the plastics that make it to a recycling facility <a href="https://ellenmacarthurfoundation.org/plastics-and-the-circular-economy-deep-dive">can’t be reused</a> in exactly the same way they were used before – the recycling process degrades the material, so it loses utility and value. Instead of making a plastic cup that is downgraded each time it gets recycled, manufacturers could potentially make plastics once, collect them and reuse them on and on.</p>
<p>Conventional recycling requires careful sorting of all the collected materials, which can be hard with so many different plastics. Here in the U.S., collection happens mainly through <a href="https://www.container-recycling.org/index.php/issues/single-stream-recycling">single stream recycling</a> – everything from metal cans, glass bottles, cardboard boxes and plastic cups end up in the same bin. Separating paper from metal doesn’t require complex technology, but sorting a polypropylene container from a polyethylene milk jug is hard to do without the occasional mistake. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/554113/original/file-20231016-20-hwyi6k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Two workers, in bright yellow, stand at a conveyor belt covered in plastics in a recycling facility." src="https://images.theconversation.com/files/554113/original/file-20231016-20-hwyi6k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/554113/original/file-20231016-20-hwyi6k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/554113/original/file-20231016-20-hwyi6k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/554113/original/file-20231016-20-hwyi6k.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/554113/original/file-20231016-20-hwyi6k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/554113/original/file-20231016-20-hwyi6k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/554113/original/file-20231016-20-hwyi6k.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Recycling workers sort through materials.</span>
<span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/OhioRecycling/d1c2014b8c194d55b9f06a328b2dd4a5/photo?Query=recycling%20plant&mediaType=photo&sortBy=&dateRange=Anytime&totalCount=181&currentItemNo=22&vs=true">AP Photo/Mark Gillispie</a></span>
</figcaption>
</figure>
<p>When two different plastics are mixed together during recycling, their useful properties are hugely reduced – to the point of <a href="https://www.scientificamerican.com/article/why-its-so-hard-to-recycle-plastic/">making them useless</a>. </p>
<p>But say you can recycle one of these plastics by a different method, so it doesn’t end up contaminating the recycling stream. When we mixed samples of polypropylene with a polymer we made, we were <a href="https://doi.org/10.1126/science.adh3353">still able to depolymerize</a> – or break down the material – and regain our building blocks without chemically affecting the polypropylene. This indicated that a contaminated waste stream could still recover its value, and the material in it could go on to be recycled, either mechanically or chemically. </p>
<h2>Plastics we need − but more recyclable</h2>
<p>In <a href="https://doi.org/10.1126/science.adh3353">a study published in October 2023</a>, our team developed a series of polymers with only two simple building blocks – one soft polymer and one hard polymer – that mimicked polyolefins but could also be chemically recycled.</p>
<p>Connecting two different polymers together multiple times until they form a single, long molecule creates what’s called a <a href="https://doi.org/10.1021/jacsau.1c00500">multiblock polymer</a>. Just by adjusting how much of each polymer type goes into the multiblock polymer, our team created a wide range of materials with properties that spanned across polyolefin types. But creating these multiblock polymers is easier said than done. </p>
<p>To link these hard and soft polymers, we <a href="https://doi.org/10.1126/science.adh3353">adapted a technique</a> that had previously been used only on very small molecules. This method is improved relative to traditional methods of making polymers in a step-by-step fashion, developed in the 1920s, where the reactive groups on the end of the molecules need to be exactly matched. </p>
<p>In our method, the reactive groups are now the same as each other, meaning we didn’t have to worry about pairing the ends of each building block to make polymers that can compete with the polyolefins we already use. Using the same strategy, applied in reverse by adding hydrogen, we could disconnect the polymers back into their building blocks and easily separate them to use again. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/554857/original/file-20231019-21-9enk8w.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A graph showing a steady increase in single-use plastic use across all plastic types shown, from X to projected in 2050." src="https://images.theconversation.com/files/554857/original/file-20231019-21-9enk8w.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/554857/original/file-20231019-21-9enk8w.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=302&fit=crop&dpr=1 600w, https://images.theconversation.com/files/554857/original/file-20231019-21-9enk8w.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=302&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/554857/original/file-20231019-21-9enk8w.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=302&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/554857/original/file-20231019-21-9enk8w.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=380&fit=crop&dpr=1 754w, https://images.theconversation.com/files/554857/original/file-20231019-21-9enk8w.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=380&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/554857/original/file-20231019-21-9enk8w.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=380&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Realized and predicted production of commodity plastics through 2050.</span>
<span class="attribution"><a class="source" href="https://www.energy.gov/sites/default/files/2021/01/f82/Plastics%20Innovation%20Challenge%20Draft%20Roadmap.pdf">International Energy Agency</a></span>
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</figure>
<p>With an almost <a href="https://www.reuters.com/business/environment/plastic-consumption-course-nearly-double-by-2050-research-2023-02-27/">twofold increase in annual plastic use</a> projected through 2050, the complexity and quantity of plastic recycling will only increase. It’s an important consideration when designing new materials and products. </p>
<p>Using just two building blocks to make plastics that have a huge variety of properties can go a long way toward reducing and streamlining the number of different plastics used to make the products we need. Instead of needing one plastic to make something pliable, another for something stiff, and a third, fourth and fifth for properties in between, we could control the behavior of plastics by just changing how much of each building block is there.</p>
<p>Although we’re still in the process of answering some big questions about these polymers, we believe this work is a step in the right direction toward more sustainable plastics. </p>
<p>We were <a href="https://doi.org/10.1126/science.adh3353">able to create materials</a> that mimic the properties of plastics the world relies on, and our sights are now set on creating plastic compositions that you couldn’t with existing methods.</p><img src="https://counter.theconversation.com/content/215652/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Katherine Harry receives funding from RePLACE (Redesigning Polymers to Leverage a Circular Economy) funded by the Office of Science of the US Department of Energy.</span></em></p><p class="fine-print"><em><span>Emma Rettner receives funding from RePLACE (Redesigning Polymers to Leverage a Circular Economy) funded by the Office of Science of the US Department of Energy.</span></em></p>A team of scientists has developed a method for creating a new class of plastic materials that are potentially more recyclable than single-use plastics.Katherine Harry, PhD Student in Chemistry, Colorado State UniversityEmma Rettner, PhD Candidate in Materials Science and Engineering, Colorado State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2084342023-10-13T12:31:53Z2023-10-13T12:31:53ZThis engineering course has students use their brainwaves to create performing art<figure class="align-right ">
<img alt="Text saying: Uncommon Courses, from The Conversation" src="https://images.theconversation.com/files/499014/original/file-20221205-17-kcwec8.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/499014/original/file-20221205-17-kcwec8.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=375&fit=crop&dpr=1 600w, https://images.theconversation.com/files/499014/original/file-20221205-17-kcwec8.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=375&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/499014/original/file-20221205-17-kcwec8.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=375&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/499014/original/file-20221205-17-kcwec8.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=471&fit=crop&dpr=1 754w, https://images.theconversation.com/files/499014/original/file-20221205-17-kcwec8.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=471&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/499014/original/file-20221205-17-kcwec8.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=471&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><em><a href="https://theconversation.com/topics/uncommon-courses-130908">Uncommon Courses</a> is an occasional series from The Conversation U.S. highlighting unconventional approaches to teaching.</em> </p>
<h2>Title of course:</h2>
<p>“Arts and Geometry”</p>
<h2>What prompted the idea for the course?</h2>
<p>After a serious injury in 2016, I started drawing and painting during my recovery as a form of self-taught art therapy. I found the experience transformative. During my recovery, I rediscovered Pablo Picasso’s artwork and the geometry of his cubism, which inspired my early paintings.</p>
<p>As making art became part of my life, a desire grew to share this transformative experience with my engineering students. I wanted them to learn how to see science and engineering from a broader perspective – as an artist.</p>
<p>This led to the idea for, and development of, a course on arts and geometry in collaboration with professional artists of the Atlanta community. The play “<a href="https://www.concordtheatricals.com/p/2865/picasso-at-the-lapin-agile">Picasso at the Lapin Agile</a>,” where comedian Steve Martin imagined a conversation in a Parisian cafe between Picasso and Albert Einstein, helped inspire the course. So did a book by history and philosophy of science professor Arthur Miller, “<a href="https://www.arthurimiller.com/books/einstein-picasso/">Einstein, Picasso: Space, Time and the Beauty That Causes Havoc</a>.” </p>
<h2>What does the course explore?</h2>
<p>The course introduces engineering students to the geometry of manifolds – that is, cylinders, spheres or hyperboloids, and more complex surfaces, like a crumpled piece of paper or a rippled kale leaf. It then looks at how these concepts influenced modern arts and sciences: Picasso’s cubism and Einstein’s relativity. Cubism combines many angles to create a new way of seeing things, whereas Einstein’s theory changes how we think about time, which isn’t separate from the space around us – they are intertwined. </p>
<p>The course is integrated with weekly art labs taught over the years by Atlanta professional artists <a href="https://www.createdbyemily.com">Emily Vickers</a>, <a href="https://www.rachelgrantstudio.com/">Rachel Grant</a>, <a href="https://research.gatech.edu/anna-doll">Anna Doll</a> and <a href="https://jerushiagraham.wixsite.com/jerushiagraham">Jerushia Graham</a>, and with the support of music technologist <a href="https://mikewinters.io/">Mike Winters</a>. The artists teach students the fundamentals of several art mediums: <a href="https://issuu.com/ceebuzz/docs/like_picasso_and_einstein_book_fina">pencil and charcoal drawing</a>, printmaking, <a href="https://issuu.com/ceebuzz/docs/forms_and_expression_book_2019_fedele_grant">oil painting</a> and sculptures. </p>
<p>We also teach students how to create performing art using their brainwaves. Brainwaves are produced when we are engaged in any activity. They can be measured by electroencephalography – or EEG – headsets.</p>
<p>Students learn to create auditory or dynamic visual representations of our mind activity when we think, reason, create, dance or relax doing nothing. For example, brainwaves produced by a dancer can be transformed into musical sounds, an auditory representation of the dancer’s movements. Similarly, the brainwaves of an artist making a painting, or those of a mathematician deriving an equation, can be transformed into music that mirrors the act of creating art or math.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/ZB7Gk1lVZFM?wmode=transparent&start=419" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Mind melody performance: The brainwaves of artist Rachel Grant making a painting, engineer Francesco Fedele developing equations and choreographer Bella Dorado dancing are transformed into musical sounds designed by student Dennis Frank.</span></figcaption>
</figure>
<p>The same brainwaves can power on or off a set of pumps that produce water jets in a tank, a system designed by professor <a href="https://lai-etal-lab.github.io/author/chris-ck-lai/">Chris Lai</a> and students Muhammad Mustafa and Alexander Zimmer. These jets interact among themselves to produce a disordered turbulent flow in the water tank. The shape and motion of vortexes generated by <a href="https://www.youtube.com/watch?v=OFLOn6fzMKY&ab_channel=73gabbiano">turbulence</a> are a dynamic visualization of the human mind’s activity.</p>
<figure class="align-center ">
<img alt="A student dances on stage while another paints in the background." src="https://images.theconversation.com/files/540377/original/file-20230801-17-2r0ssq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/540377/original/file-20230801-17-2r0ssq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=340&fit=crop&dpr=1 600w, https://images.theconversation.com/files/540377/original/file-20230801-17-2r0ssq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=340&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/540377/original/file-20230801-17-2r0ssq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=340&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/540377/original/file-20230801-17-2r0ssq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=427&fit=crop&dpr=1 754w, https://images.theconversation.com/files/540377/original/file-20230801-17-2r0ssq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=427&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/540377/original/file-20230801-17-2r0ssq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=427&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Choreographer Bella Dorado dances to sounds produced by the brainwaves of student Tanisha Chanda while she paints a waterscape.</span>
<span class="attribution"><span class="source">Francesco Fedele</span></span>
</figcaption>
</figure>
<h2>Why is this course relevant now?</h2>
<p>Civil engineering can be explained and taught using the physics and mathematics of Isaac Newton and Gottfried Leibniz, from the 17th century: the concepts of derivatives and force being proportional to acceleration.</p>
<p>In our fast-changing world, there are exciting discoveries happening in science and technology, like in the understanding of the universe, artificial intelligence and quantum computing.</p>
<p>To prepare for the challenges posed by these recent discoveries, engineering students should be familiar with special mathematical tools developed by 20th-century geniuses such as Elie Cartan and Einstein. Such tools empower students to gain insights such as uncovering hidden geometric structures of complex physical systems or of large amounts of data. Normally, engineering classes don’t teach these topics.</p>
<p>The course also involves the participation of Colombian university students interested in arts for <a href="https://www.100kstrongamericas.org/roboarts-initiative/">the RobotArts Initiative</a>. Such an international exchange seeks to increase the number of Latino engineering students with skills in the arts, engineering and robotics. Besides taking my course, the students from Colombia also take a course on robotics. </p>
<h2>What’s a critical lesson from the course?</h2>
<p>Students realize the <a href="https://doi.org/10.2105/AJPH.2008.156497">mental health benefits</a> of practicing arts. They feel more self-confident and have more <a href="https://apps.who.int/iris/handle/10665/329834">self-esteem</a> because they have created something.</p>
<p>Performing art live empowers students’ self-expression. By not relying on memorization, these performances stimulate spontaneous creativity, improvisation and free thinking.</p>
<figure class="align-center ">
<img alt="Students dance on stage." src="https://images.theconversation.com/files/540378/original/file-20230801-20-t0wcs4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/540378/original/file-20230801-20-t0wcs4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=335&fit=crop&dpr=1 600w, https://images.theconversation.com/files/540378/original/file-20230801-20-t0wcs4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=335&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/540378/original/file-20230801-20-t0wcs4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=335&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/540378/original/file-20230801-20-t0wcs4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=420&fit=crop&dpr=1 754w, https://images.theconversation.com/files/540378/original/file-20230801-20-t0wcs4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=420&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/540378/original/file-20230801-20-t0wcs4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=420&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Students Dennis Frank, Muhammad Mustafa and Alexander Zimmer performing brain art. In the background, software converts student performers’ brainwaves into music and water turbulence in a tank designed by professor Chris Lai.</span>
<span class="attribution"><span class="source">Francesco Fedele</span></span>
</figcaption>
</figure>
<h2>What materials does the course feature?</h2>
<p>• “<a href="https://www.worldcat.org/title/1112495919">Spacetime and Geometry: An Introduction to General Relativity,</a>” by Sean M. Carroll, Cambridge University Press, 2019 – a textbook that covers the foundations of the general relativity and mathematical formalism.</p>
<p>• “<a href="https://www.arthurimiller.com/books/einstein-picasso/">Einstein, Picasso: Space, Time, and the Beauty That Causes Havoc_</a> by Arthur J. Miller, Perseus Books Group, 2001 – a biography of Albert Einstein and Pablo Picasso.</p>
<p>• EEG headsets to acquire brainwaves and <a href="https://supercollider.github.io/">SuperCollider</a> software to synthesize them into music. </p>
<h2>What will the course prepare students to do?</h2>
<p>The course will prepare students to think like an artist, using abstraction, imagination and fluid thinking. They will tackle with confidence the new engineering quests and challenges of the 21st century. The challenges encompass sustainable urban and ocean infrastructure design for extreme weather, global warming mitigation, clean water and energy, quantum computing, cybersecurity and <a href="https://link.springer.com/chapter/10.1007/978-3-030-69978-9_4">ethical use of AI</a>.</p><img src="https://counter.theconversation.com/content/208434/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Francesco Fedele does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Art and science combine in this engineering course to let students turn their brainwaves into creative works.Francesco Fedele, Associate Professor of Civil and Environmental Engineering, Georgia Institute of TechnologyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2137152023-09-25T12:20:30Z2023-09-25T12:20:30Z‘Design of Coffee’ course teaches engineering through brewing the perfect cup of coffee<figure><img src="https://images.theconversation.com/files/549189/original/file-20230919-29-u8o1mb.jpg?ixlib=rb-1.1.0&rect=7%2C21%2C4785%2C3168&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">UC Davis students learn the fundamentals of both engineering and brewing coffee.</span> <span class="attribution"><span class="source">UC Davis</span></span></figcaption></figure><figure class="align-right ">
<img alt="Text saying: Uncommon Courses, from The Conversation" src="https://images.theconversation.com/files/499014/original/file-20221205-17-kcwec8.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/499014/original/file-20221205-17-kcwec8.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=375&fit=crop&dpr=1 600w, https://images.theconversation.com/files/499014/original/file-20221205-17-kcwec8.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=375&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/499014/original/file-20221205-17-kcwec8.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=375&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/499014/original/file-20221205-17-kcwec8.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=471&fit=crop&dpr=1 754w, https://images.theconversation.com/files/499014/original/file-20221205-17-kcwec8.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=471&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/499014/original/file-20221205-17-kcwec8.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=471&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><em><a href="https://theconversation.com/topics/uncommon-courses-130908">Uncommon Courses</a> is an occasional series from The Conversation U.S. highlighting unconventional approaches to teaching.</em> </p>
<h2>Title of course:</h2>
<p>The Design of Coffee: An Introduction to Chemical Engineering</p>
<h2>What prompted the idea for the course?</h2>
<p>In 2012, my colleague professor Tonya Kuhl and I were drinking coffee and brainstorming how to improve our senior-level laboratory course in chemical engineering. Tonya looked at her coffee and suggested, “How about we have the students reverse-engineer a Mr. Coffee drip brewer to see how it works?” </p>
<p>A light bulb went off in my head, and I said, “Why not make a whole course about coffee to introduce lots of students to chemical engineering?” </p>
<p>And that’s what we did. We developed The Design of Coffee as a freshman seminar for 18 students in 2013, and, since then, the course has grown to over 2,000 general education students per year at the University of California, Davis.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/549190/original/file-20230919-25-c9imuf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A student wearing a flannel shirt uses a white microscope, with a pile of coffee beans and a metal scoop sitting next to them on the table." src="https://images.theconversation.com/files/549190/original/file-20230919-25-c9imuf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/549190/original/file-20230919-25-c9imuf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/549190/original/file-20230919-25-c9imuf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/549190/original/file-20230919-25-c9imuf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/549190/original/file-20230919-25-c9imuf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/549190/original/file-20230919-25-c9imuf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/549190/original/file-20230919-25-c9imuf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A student uses a microscope to look at coffee beans in The Design of Coffee lab.</span>
<span class="attribution"><span class="source">UC Davis</span></span>
</figcaption>
</figure>
<h2>What does the course explore?</h2>
<p>The course focus is hands-on experiments with roasting, brewing and tasting in our coffee lab. </p>
<p>For example, students measure the energy they use while roasting to illustrate the law of <a href="https://www.britannica.com/science/conservation-of-energy">conservation of energy</a>, they measure how <a href="https://www.sciencedirect.com/topics/nursing-and-health-professions/ph-measurement">the pH of the coffee</a> changes after brewing to illustrate the kinetics of chemical reactions, and they measure how the <a href="https://doi.org/10.1038/s41598-021-85787-1">total dissolved solids</a> in the brewed coffee relates to time spent brewing to illustrate the principle of <a href="https://en.wikipedia.org/wiki/Mass_transfer">mass transfer</a>. </p>
<p>The course culminates in an engineering design contest, where the students compete to make the best-tasting coffee using the least amount of energy. It’s a classic engineering optimization problem, but one that is broadly accessible – and tasty.</p>
<h2>Why is this course relevant now?</h2>
<p>Coffee plays <a href="https://www.smithsonianmag.com/videos/the-history-of-coffee-culture-in-america/">a huge role in culture</a>, <a href="https://doi.org/10.3945/jn.116.233940">diet</a> and <a href="https://www.ncausa.org/Research-Trends/Economic-Impact">the U.S.</a> and <a href="https://icocoffee.org/">global economy</a>. But historically, relatively little academic work has focused on coffee. There are entire academic programs on wine and beer at many major universities, but almost none on coffee. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/549191/original/file-20230919-15-46yjz8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A student wearing a black UC Davis sweatshirt holds a glass cup of coffee" src="https://images.theconversation.com/files/549191/original/file-20230919-15-46yjz8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/549191/original/file-20230919-15-46yjz8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/549191/original/file-20230919-15-46yjz8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/549191/original/file-20230919-15-46yjz8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/549191/original/file-20230919-15-46yjz8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/549191/original/file-20230919-15-46yjz8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/549191/original/file-20230919-15-46yjz8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Many students who don’t like coffee develop a taste for it over the course of the class.</span>
<span class="attribution"><span class="source">UC Davis</span></span>
</figcaption>
</figure>
<p>The Design of Coffee helps fill a huge unmet demand because students are eager to learn about the beverage that they already enjoy. Perhaps most surprisingly, many of our students enter the course professing to hate coffee, but by the end of the course they are roasting and brewing their own coffee beans at home.</p>
<h2>What’s a critical lesson from the course?</h2>
<p>Many students are shocked to learn that black coffee can have <a href="https://doi.org/10.1111/1750-3841.16531">fruity, floral or sweet flavors</a> without adding any sugar or syrups. The most important lesson from the course is that engineering is really a quantitative way to think about problem-solving. </p>
<p>For example, if the problem to solve is “make coffee taste sweet without adding sugar,” then an engineering approach provides you with a tool set to tackle that problem quantitatively and rigorously. </p>
<h2>What materials does the course feature?</h2>
<p>Tonya and I originally self-published our lab manual, <a href="https://www.amazon.com/Design-Coffee-Engineering-Approach/dp/B09FSCDY18">The Design of Coffee: An Engineering Approach</a>, to keep prices low for our students. </p>
<p>Now in its third edition, it has sold more than 15,000 copies and has been translated to <a href="https://www.amazon.com/dise%C3%B1o-del-caf%C3%A9-aproximaci%C3%B3n-ingenier%C3%ADa/dp/B08TQ42NS2/">Spanish</a>, with Korean and Indonesian translations on the way.</p>
<h2>What will the course prepare students to do?</h2>
<p>Years ago, a student in our class told the campus newspaper, “I had no idea there was an engineering way to think about coffee!” Our main goal is to teach students that there is an engineering way to think about anything. </p>
<p>The engineering skills and mindset we teach equally prepare students to design a multimillion-dollar biofuel refinery, a billion-dollar pharmaceutical production facility or, most challenging of all, a naturally sweet and delicious $3 cup of coffee. Our course is the first step in preparing students to tackle these problems, as well as new problems that no one has yet encountered.</p><img src="https://counter.theconversation.com/content/213715/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>William D. Ristenpart receives funding from the National Science Foundation, the Coffee Science Foundation, and the Specialty Coffee Association. </span></em></p>In an engineering course at UC Davis, students learn all the nuances that go into brewing ‘a truly excellent cup of coffee.’William D. Ristenpart, Professor of Chemical Engineering, University of California, DavisLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2117062023-09-14T12:29:46Z2023-09-14T12:29:46ZHeating and cooling space habitats isn’t easy – one engineering team is developing a lighter, more efficient solution<figure><img src="https://images.theconversation.com/files/546491/original/file-20230905-23-lf6ix5.jpg?ixlib=rb-1.1.0&rect=18%2C27%2C6006%2C3983&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">It's hard to keep a spacecraft cool, but ongoing research on the International Space Station might yield a solution. </span> <span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/SpaceXStarshipTestFlight/bd7689d98def429b9461fd88e6ce5ae0/photo?Query=rocket&mediaType=photo&sortBy=&dateRange=Anytime&totalCount=697&currentItemNo=48&vs=true">AP Photo/Eric Gay</a></span></figcaption></figure><p><a href="https://www.science.org/content/article/chinese-spacraft-successfully-lands-moons-far-side-and-sends-pictures-back-home">China</a>, <a href="https://theconversation.com/indias-chandrayaan-3-landed-on-the-south-pole-of-the-moon-a-space-policy-expert-explains-what-this-means-for-india-and-the-global-race-to-the-moon-212171">India</a> and <a href="https://www.nasa.gov/specials/artemis/">the U.S.</a> have all achieved landing on the Moon in the 2020s.</p>
<p>Once there, their eventual goal is to <a href="https://time.com/6270882/china-moon-base-timeline/">set up a base</a>. But a successful base – along with the spacecraft that will carry people to it – must be habitable for humans. And a big part of creating a habitable base is making sure the heating and cooling systems work. </p>
<p>That’s especially true because the ambient temperature of potential places for a base can vary widely. Lunar <a href="https://www.space.com/18175-moon-temperature.html">equatorial temperatures</a> can range from minus 208 to 250 degrees Farenheit (minus 130 to 120 degrees Celsius) – and similarly, from minus 225 F to 70 F (minus 153 C to 20 C) <a href="https://solarsystem.nasa.gov/planets/mars/in-depth/">on Mars</a>.</p>
<p>In 2011, the National Academies of Science <a href="https://nap.nationalacademies.org/catalog/13048/recapturing-a-future-for-space-exploration-life-and-physical-sciences">published a report</a> outlining research in the physical and life sciences that scientists would need to do for the U.S. space program to succeed. The report emphasized the need for research about building heating and cooling systems for structures in space.</p>
<p>I’m an <a href="https://scholar.google.com/citations?user=r2-awKwAAAAJ&hl=en">engineering professor</a>, and when that report came out, I submitted a research proposal to NASA. I wanted to study something called the liquid-vapor phenomenon. Figuring out the science behind this phenomenon would help with these big questions around keeping structures in space a comfortable and habitable temperature. </p>
<p>Over a decade after we submitted a proposal, my team’s project is now being tested on the International Space Station.</p>
<h2>Going with the ‘flow’</h2>
<p>Liquid-vapor systems – or two-phase systems – involve the simultaneous flow of <a href="https://doi.org/10.1016/bs.aiht.2017.06.002">liquid and vapor</a> within a heating or cooling system. While many commercial air conditioners and refrigeration systems on Earth use two-phase systems, most systems used in spacecraft and on the International Space Station are purely liquid systems – or one-phase systems. </p>
<p>In one-phase systems, a liquid coolant moves through the system and absorbs excess heat, which raises the liquid’s temperature. This is similar to the way <a href="https://www.youtube.com/watch?v=Q56k37FsRcA">cars use radiators to cool</a>. Conversely, heated liquid in the system would eject the heat out to the ambient area, lowering the liquid’s temperature to its initial level. </p>
<p>But liquid-vapor systems could <a href="https://doi.org/10.1016/bs.aiht.2017.06.002">transfer heat more effectively</a> than these one-phase systems, and they’re much smaller and lighter than purely liquid systems. When traveling in space, you have to carry everything on the craft with you, so small and light equipment is essential.</p>
<p>There are two key processes that happen in a closed, two-phase liquid-vapor system. In one, the liquid changes to a vapor during a process called “<a href="https://doi.org/10.1007/s00231-020-02854-5">flow boiling</a>.” Just like boiling water on the stove, in flow boiling the liquid heats up and evaporates.</p>
<p>In systems used in space, the two-phase mixture passes through heat exchange components that transfer the heat generated from electronics, power devices and more into the mixture. This gradually increases the amount of vapor produced as the system absorbs heat and converts liquid to vapor. </p>
<p>Then, there’s <a href="https://doi.org/10.1016/j.ijheatmasstransfer.2013.06.044">flow condensation</a>, in which the vapor cools and returns to a liquid. During flow condensation, heat leaves the system by radiating out into space.</p>
<p>Scientists control these two processes <a href="https://doi.org/10.1016/j.ijheatmasstransfer.2023.123998">in a closed loop</a> so they can extract and use the heat that’s released during condensation. In the future, this technology could be used to control temperature in spacecraft going to the Moon, Mars or beyond, or even in settlements or habitats on the lunar and Martian surfaces.</p>
<h2>Building and testing</h2>
<p>With the grant from NASA to do this work, I designed an experimental program called the “<a href="https://doi.org/10.1016/j.ijheatmasstransfer.2023.123998">Flow Boiling and Condensation Experiment</a>.” My team built a fluid management system for the experiment and two test modules: one that helped us test flow boiling and one that helped us test flow condensation.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/546486/original/file-20230905-21-47kml0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="The International Space Station orbiting the Earth, shown below, with the Sun shown from a distance." src="https://images.theconversation.com/files/546486/original/file-20230905-21-47kml0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/546486/original/file-20230905-21-47kml0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=371&fit=crop&dpr=1 600w, https://images.theconversation.com/files/546486/original/file-20230905-21-47kml0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=371&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/546486/original/file-20230905-21-47kml0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=371&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/546486/original/file-20230905-21-47kml0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=466&fit=crop&dpr=1 754w, https://images.theconversation.com/files/546486/original/file-20230905-21-47kml0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=466&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/546486/original/file-20230905-21-47kml0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=466&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The Flow Boiling and Condensation Experiment is undergoing tests on the International Space Station.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/illustration/international-space-station-orbiting-earth-royalty-free-illustration/645390554">3DSculptor/iStock via Getty Images</a></span>
</figcaption>
</figure>
<p>Right now, the <a href="https://www.nasa.gov/content/cooling-system-keeps-space-station-safe-productive">equipment used for heating and cooling</a> in space was designed based on experiments in Earth’s gravity. Our flow boiling and condensation experiment seeks to change that.</p>
<p><a href="https://doi.org/10.1016/j.ijheatmasstransfer.2023.124296">First, we tested</a> whether the system and modules we built worked when subjected to Earth’s gravity. Once we learned they did, we sent them up in a <a href="https://www.nasa.gov/analogs/parabolic-flight">parabolic flight aircraft</a>. This craft <a href="https://theconversation.com/what-is-the-zero-gravity-that-people-experience-in-the-vomit-comet-or-space-flight-133144">simulated reduced gravity</a> so we could get an idea of how the system performed in an environment similar to that of space.</p>
<p>In August 2021 we completed the flow boiling module and launched it to the International Space Station for <a href="https://doi.org/10.1016/j.ijheatmasstransfer.2023.124000">testing in zero gravity</a>. By July 2022 we’d completed the boiling experiments. In August 2023 the flow condensation module followed, and we’ll start working on the final condensation tests soon.</p>
<h2>Responding to reduced gravity</h2>
<p><a href="https://doi.org/10.1016/j.ijheatmasstransfer.2023.123998">Liquid-vapor flow systems</a> are far more sensitive to gravity than the purely liquid systems used now, so it’s harder to design ones that work under reduced gravity. </p>
<p>The mechanism behind these systems has to do with the motion of liquid relative to the vapor, and what that motion looks like depends on <a href="https://www.britannica.com/science/buoyancy">a concept called buoyancy</a>.</p>
<p>Buoyancy is determined by gravity as well as the density difference between liquid and vapor. So any change in gravity affects the system’s buoyancy, and thus the movement of the vapor relative to the liquid. </p>
<p>In space, there are also different strengths of gravity that the systems might need to operate under. Space vehicles experience <a href="https://www.nasa.gov/audience/forstudents/k-4/stories/nasa-knows/what-is-microgravity-k4.html">microgravity</a> – near weightlessness – while a lunar habitat would operate under gravity conditions about <a href="https://www.sciencedirect.com/topics/engineering/lunar-gravity">one-sixth the strength of Earth’s gravity</a>, and a Martian habitat would be operating under gravity <a href="https://phys.org/news/2016-12-strong-gravity-mars.html">three-eighths the strength</a> of Earth’s gravity. </p>
<p>Our team is working on designing flow boiling and condensation models that can work under all these levels of reduced gravity.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/xDZdNxPFits?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Vapor condensing in microgravity in a flow condensation module.</span></figcaption>
</figure>
<h2>Applications for space habitats</h2>
<p>This equipment could one day go into a human habitat on the Moon or Mars, where it would help maintain comfortable temperatures for people and machinery inside. A <a href="https://theconversation.com/electric-heat-pumps-use-much-less-energy-than-furnaces-and-can-cool-houses-too-heres-how-they-work-154779">heat pump</a> using our flow boiling and flow condensation systems could extract the heat that astronauts and their machines give off. It would then send this collected heat out of the habitat to keep the inside cool – similar to the way air conditioners on Earth work. </p>
<p>The temperatures in space can be extreme and hostile to people, but with these technologies, my team might one day help create craft and habitats that allow people to explore the Moon and beyond.</p><img src="https://counter.theconversation.com/content/211706/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Issam Mudawar receives funding from NASA. </span></em></p>You can’t bring your AC to space, unfortunately, but innovative flow boiling and condensation research might lead to lighter, more efficient heating and cooling on spacecraft.Issam Mudawar, Betty Ruth and Milton B. Hollander Family Professor of Mechanical Engineering, Purdue UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2107502023-08-30T15:07:26Z2023-08-30T15:07:26ZCurious Kids: how does a tower crane go up and down?<p><strong>How does a crane go up and down? – Spencer, aged four, UK</strong></p>
<p>When you see the metal arms of a crane – known properly as a tower crane – against the skyline, you know a new building is going up in your city or town. </p>
<p>Many of the materials and machines on a big building site are too heavy for people to lift by themselves without getting hurt. Using a tower crane means that building materials can be lifted easily and quickly, even when something very tall is being built, such as a skyscraper. </p>
<p>Tower cranes are huge. They are transported to a building site in many separate small sections and put together on site, almost like a Lego kit. </p>
<hr>
<figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/282267/original/file-20190702-126345-1np1y7m.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/282267/original/file-20190702-126345-1np1y7m.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=293&fit=crop&dpr=1 600w, https://images.theconversation.com/files/282267/original/file-20190702-126345-1np1y7m.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=293&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/282267/original/file-20190702-126345-1np1y7m.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=293&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/282267/original/file-20190702-126345-1np1y7m.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=368&fit=crop&dpr=1 754w, https://images.theconversation.com/files/282267/original/file-20190702-126345-1np1y7m.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=368&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/282267/original/file-20190702-126345-1np1y7m.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=368&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><em><a href="https://theconversation.com/au/topics/curious-kids-36782">Curious Kids</a> is a series by <a href="https://theconversation.com/uk">The Conversation</a> that gives children the chance to have their questions about the world answered by experts. If you have a question you’d like an expert to answer, send it to <a href="mailto:curiouskids@theconversation.com">curiouskids@theconversation.com</a> and make sure you include the asker’s first name, age and town or city. We won’t be able to answer every question, but we’ll do our very best.</em></p>
<hr>
<p>In order to lift heavy things like concrete, <a href="https://www.mdpi.com/2075-5309/13/1/115">tower cranes</a> themselves must be very strong, so they are made from steel. Tower cranes come in many different sizes and many weigh more than 100 tonnes. They can carry up to <a href="https://thinkwelty.com/how-do-tower-cranes-work/">around 18 tonnes</a> – about the weight of 12 cars.</p>
<h2>Building the crane</h2>
<p>Before the tower crane can be put up, a strong foundation is normally built out of concrete and steel. This means that that the ground below will not collapse when the crane is lifting heavy materials.</p>
<p>When the foundation is ready, the bottom section of the tower is lifted by another crane (usually one attached to the top of a truck) and fixed on it. The other sections of the tower are then lifted and stacked on top of each other. Each section of the tower has a ladder inside it, so that the people building the crane can climb up and bolt the sections together. </p>
<p>Once the last section of the main tower is lifted and fixed, a big metal ring that can spin around is attached on top of it. There’s a driver up at the top of the crane and they sit in a cabin fixed to the side of this ring. This means that the driver has a good view of everywhere around the crane, because the cabin can move around in a circle. </p>
<figure class="align-center ">
<img alt="Man inside crane cabin smiling" src="https://images.theconversation.com/files/543769/original/file-20230821-15-yctdpp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/543769/original/file-20230821-15-yctdpp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=300&fit=crop&dpr=1 600w, https://images.theconversation.com/files/543769/original/file-20230821-15-yctdpp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=300&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/543769/original/file-20230821-15-yctdpp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=300&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/543769/original/file-20230821-15-yctdpp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=377&fit=crop&dpr=1 754w, https://images.theconversation.com/files/543769/original/file-20230821-15-yctdpp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=377&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/543769/original/file-20230821-15-yctdpp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=377&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">An engineer operates a tower crane from the cabin.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/engineer-operator-crane-action-he-sit-1304722618">Oleksii Sidorov/Shutterstock</a></span>
</figcaption>
</figure>
<p>A steel frame which becomes the highest part of the tower crane is then lifted and fixed directly on top of the rotating ring. </p>
<p>Then, the bit of the crane which sticks out horizontally – the <a href="https://www.ny-engineers.com/blog/the-role-of-tower-cranes-in-high-rise-building-projects">lifting arm</a> – can be attached. It is connected to the rotating ring and tied to the highest steel frame of the tower with big, strong wire ropes. </p>
<p>The lifting arm also comes in sections which are connected together by strong bolts. In order to put these sections together safely, fitters wear harnesses tied to a stable point to ensure that they don’t fall from the heights they are working at. </p>
<p>Before the crane can be used, engineers check to make sure it is fixed and working perfectly. When the tower crane is in use, engineers also keep <a href="https://www.premierline.co.uk/knowledge-centre/adverse-weather-increases-risk-of-tower-crane-collapse.html">an eye on the weather</a>. Sometimes the crane can’t be used when the wind is too strong, because it might fall over. </p>
<p>The crane is ready to work. To balance the weight of the lifting arm when it is carrying things, some heavy weights made out of concrete are lifted and placed on the opposite side. </p>
<p>In order to lift things, a wire rope with a hook is connected to the lifting arm. By pulling or lowering this rope, things on the building site can be lifted or lowered – and the new skyscraper in your town can be built.</p><img src="https://counter.theconversation.com/content/210750/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kenneth Awinda does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Tower cranes come in many different sizes, and many weigh more than 100 tonnes.Kenneth Awinda, Senior Lecturer, School of Civil Engineering and Surveying, University of PortsmouthLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2105912023-08-29T12:25:03Z2023-08-29T12:25:03ZMachines can’t always take the heat − two engineers explain the physics behind how heat waves threaten everything from cars to computers<figure><img src="https://images.theconversation.com/files/544645/original/file-20230824-17-rzbu1.jpg?ixlib=rb-1.1.0&rect=85%2C54%2C5090%2C3391&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Extreme heat can affect how well machines function, and the fact that many machines give off their own heat doesn't help. </span> <span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/MoroccoRenaultSandero/b86810360f694e719364ff6cfb327f27/photo?Query=manufacturing&mediaType=photo&sortBy=&dateRange=Anytime&totalCount=317&currentItemNo=NaN&vs=true">AP Photo/Abdeljalil Bounhar</a></span></figcaption></figure><p>Not only people need to stay cool, especially in a summer of <a href="https://www.usatoday.com/story/news/weather/2023/07/18/us-temperature-records-summer-heat-wave/70425231007/">record-breaking heat waves</a>. Many machines, including cellphones, data centers, cars and airplanes, become less efficient and degrade more quickly in <a href="https://doi.org/10.1049/iet-est.2015.0050">extreme heat</a>. Machines generate their own heat, too, which can make hot temperatures around them even hotter. </p>
<p>We are <a href="https://scholar.google.com/citations?user=_C33NmEAAAAJ&hl=en">engineering researchers</a> <a href="https://scholar.google.com/citations?user=q0jrPekAAAAJ&hl=en">who study</a> how machines manage heat and ways to effectively recover and reuse heat that is otherwise wasted. There are several ways extreme heat affects machines.</p>
<p>No machine is perfectly efficient – all machines face some internal friction during operation. This friction causes machines to dissipate some heat, so the hotter it is outside, the hotter the machine will be. </p>
<p><a href="https://support.apple.com/en-us/HT201678">Cellphones</a> and similar devices with <a href="http://www.nrel.gov/docs/fy13osti/58145.pdf">lithium ion batteries</a> stop working as well when operating in climates above 95 degrees Farenheit (35 degrees Celsius) – this is to avoid overheating and increased stress on the electronics.</p>
<p>Cooling designs that use innovative <a href="https://ieeexplore.ieee.org/abstract/document/6188826">phase-changing fluids</a> can help keep machines cool, but in most cases heat is still ultimately dissipated into the air. So, the hotter the air, the harder it is to keep a machine cool enough to function efficiently. </p>
<p>Plus, the closer together machines are, the more dissipated heat there will be in the surrounding area. </p>
<h2>Deforming materials</h2>
<p>Higher temperatures, either from the weather or the excess heat radiated from machinery, can cause materials in machinery to deform. To understand this, consider what temperature means at the molecular level. </p>
<p>At <a href="https://chem.libretexts.org/Bookshelves/General_Chemistry/CLUE%3A_Chemistry_Life_the_Universe_and_Everything/05%3A_Systems_Thinking/5.1%3A_Temperature">the molecular scale</a>, temperature is a measure of how much molecules are vibrating. So the hotter it is, the more the molecules that make up everything from the air to the ground to materials in machinery vibrate.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/sNvMfuOvHwg?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">When metal is heated, the molecules in it vibrate faster and the space between them moves farther apart. This leads the metal to expand.</span></figcaption>
</figure>
<p>As the temperature increases and the molecules vibrate more, the average space between them grows, causing most materials to expand as they heat up. Roads are one place to see this – hot concrete expands, gets constricted and <a href="https://www.heraldnet.com/news/heat-wave-melted-county-roads-buckled-sidewalks/">eventually cracks</a>. This phenomenon can happen to machinery, too, and thermal stresses are just the beginning of the problem.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/544793/original/file-20230825-17-s9qfkc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A close-up of a street with several cracks running through the asphalt and a white paint stripe." src="https://images.theconversation.com/files/544793/original/file-20230825-17-s9qfkc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/544793/original/file-20230825-17-s9qfkc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/544793/original/file-20230825-17-s9qfkc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/544793/original/file-20230825-17-s9qfkc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/544793/original/file-20230825-17-s9qfkc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/544793/original/file-20230825-17-s9qfkc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/544793/original/file-20230825-17-s9qfkc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Streets crack under heat because higher temperatures create more space between vibrating molecules, causing the material to expand and deform.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/cracked-asphalt-royalty-free-image/1266178787?phrase=broken+street+hot&adppopup=true">Priscila Zambotto/Moment via Getty Images</a></span>
</figcaption>
</figure>
<h2>Travel delays and safety risks</h2>
<p>High temperatures can also change the way oils in your car’s engine behave, leading to potential engine failures. For example, if a heat wave makes it 30 degrees F (16.7 degrees C) hotter than normal, the viscosity – or thickness – of typical car engine oils can change <a href="https://wiki.anton-paar.com/kr-en/engine-oil/">by a factor of three</a>. </p>
<p>Fluids like engine oils become thinner as they heat up, so if it gets too hot, the oil may not be thick enough to properly lubricate and protect engine parts from increased wear and tear.</p>
<p>Additionally, a hot day will cause the air inside your tires to expand and increases the tire pressure, which could <a href="https://www.athensreview.com/news/impact-of-excessive-heat-on-tires/article_31542372-3169-11ee-a135-3711984fefc6.html">increase wear and the risk of skidding</a>. </p>
<p>Airplanes are also not designed to take off at extreme temperatures. As it gets hotter outside, air starts to expand and takes up more space than before, making it thinner or less dense. This <a href="https://www.washingtonpost.com/business/2023/08/01/climate-change-extreme-heat-is-making-air-travel-worse/51ae039c-3077-11ee-85dd-5c3c97d6acda_story.html">reduction in air density</a> decreases the amount of weight the plane can support during flight, which can cause significant <a href="https://www.usatoday.com/story/travel/airline-news/2023/07/14/extreme-heat-airplane-flight-delay-cancellation/70415739007/">travel delays</a> or flight cancellations. </p>
<h2>Battery degradation</h2>
<p>In general, the electronics contained in devices like cellphones, personal computers and data centers consist of many kinds of materials that all respond differently to temperature changes. These materials are all located next to each other in tight spaces. So as the temperature increases, different kinds of materials deform differently, potentially leading to <a href="https://www.pcmag.com/news/asus-confirms-thermal-stress-is-killing-the-rog-ally-sd-card-reader">premature wear and failure</a>.</p>
<p>Lithium ion batteries in cars and general electronics degrade faster at higher operating temperatures. This is because higher temperatures <a href="https://doi.org/10.1016/j.jpowsour.2013.05.040">increase the rate of reactions</a> within the battery, including corrosion reactions that deplete the lithium in the battery. This process wears down its storage capacity. Recent research shows that electric vehicles <a href="https://www.recurrentauto.com/research/what-a-c-does-to-your-range">can lose about 20% of their range</a> when exposed to sustained 90-degree Farenheit weather.</p>
<p><a href="https://theconversation.com/the-factories-of-the-past-are-turning-into-the-data-centers-of-the-future-70033">Data centers</a>, which are buildings full of servers that store data, dissipate significant amounts of heat to keep their components cool. On very hot days, fans must work harder to ensure chips do not overheat. In some cases, powerful fans are not enough to cool the electronics. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/545073/original/file-20230828-94298-qbkjjs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A white room filled with large black data servers, which look like lockers." src="https://images.theconversation.com/files/545073/original/file-20230828-94298-qbkjjs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/545073/original/file-20230828-94298-qbkjjs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/545073/original/file-20230828-94298-qbkjjs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/545073/original/file-20230828-94298-qbkjjs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/545073/original/file-20230828-94298-qbkjjs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/545073/original/file-20230828-94298-qbkjjs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/545073/original/file-20230828-94298-qbkjjs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Data centers, which store large quantities of data, can overheat and require large-scale cooling − which adds to their environmental footprint.</span>
<span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/DataCenterEnergyEfficiency/1f66b88d245a4f64ac6048bb84627ef2/photo?Query=data%20center&mediaType=photo&sortBy=&dateRange=Anytime&totalCount=185&currentItemNo=1&vs=true">AP Photo/Julie Carr Smyth</a></span>
</figcaption>
</figure>
<p>To keep the centers cool, incoming dry air from the outside is often first sent through a moist pad. The water from the pad evaporates into the air and absorbs heat, which cools the air. This technique, called evaporative cooling, is usually an <a href="https://doi.org/10.1080/01457632.2018.1436418">economical and effective way</a> to keep chips at a reasonable operating temperature. </p>
<p>However, evaporative cooling can require a <a href="https://doi.org/10.1088/1748-9326/abfba1">significant amount of water</a>. This issue is problematic in regions where water is scarce. Water for cooling can add to the already <a href="https://theconversation.com/is-generative-ai-bad-for-the-environment-a-computer-scientist-explains-the-carbon-footprint-of-chatgpt-and-its-cousins-204096">intense resource footprint</a> associated with data centers. </p>
<h2>Struggling air conditioners</h2>
<p>Air conditioners struggle to perform effectively as it gets hotter outside – just when they’re needed the most. On hot days, air conditioner compressors have to work harder to <a href="https://home.howstuffworks.com/ac.htm">send the heat from homes</a> outside, which in turn disproportionally increases electricity consumption and <a href="https://doi.org/10.1029/2021EF002434">overall electricity demand</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/543804/original/file-20230821-19-xxe1t5.jpg?ixlib=rb-1.1.0&rect=12%2C0%2C8527%2C4263&q=45&auto=format&w=1000&fit=clip"><img alt="An apartment building wall with closed windows, an AC unit in each." src="https://images.theconversation.com/files/543804/original/file-20230821-19-xxe1t5.jpg?ixlib=rb-1.1.0&rect=12%2C0%2C8527%2C4263&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/543804/original/file-20230821-19-xxe1t5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=305&fit=crop&dpr=1 600w, https://images.theconversation.com/files/543804/original/file-20230821-19-xxe1t5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=305&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/543804/original/file-20230821-19-xxe1t5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=305&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/543804/original/file-20230821-19-xxe1t5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=383&fit=crop&dpr=1 754w, https://images.theconversation.com/files/543804/original/file-20230821-19-xxe1t5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=383&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/543804/original/file-20230821-19-xxe1t5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=383&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Heat waves can stress air conditioners, which are already working hard to dissipate heat.</span>
<span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/SpainHeatwave/7d830b0761634881b61119751a1aa911/photo?Query=air%20conditioner&mediaType=photo&sortBy=&dateRange=Anytime&totalCount=253&currentItemNo=28&vs=true">AP Photo/Paul White</a></span>
</figcaption>
</figure>
<p>For example, in Texas, every increase of 1.8 degrees F (1 degree C) creates a rise of <a href="https://www.iea.org/commentaries/keeping-cool-in-a-hotter-world-is-using-more-energy-making-efficiency-more-important-than-ever">about 4% in electricity demand</a>. </p>
<p>Heat leads to a staggering 50% increase in electricity demand during the summer in hotter countries, posing serious threats of <a href="https://www.washingtonpost.com/climate-environment/2022/07/11/texas-record-heat-ercot-power-grid/">electricity shortages</a> or blackouts, coupled with higher greenhouse gas emissions.</p>
<h2>How to prevent heat damage</h2>
<p>Heat waves and warming temperatures around the globe pose significant short- and long-term problems for people and machines alike. Fortunately, there are things you can do to minimize the damage. </p>
<p>First, ensure that your machines are kept in an air-conditioned, <a href="https://doi.org/10.1016/j.heliyon.2023.e16102">well-insulated space</a> or out of direct sunlight. </p>
<p>Second, consider using high-energy devices like air conditioners or charging your electric vehicle during off-peak hours when fewer people are using electricity. This can help avoid local electricity shortages.</p>
<h2>Reusing heat</h2>
<p>Scientists and engineers are developing ways to use and recycle the vast amounts of heat dissipated from machines. One simple example is using the waste heat from data centers <a href="https://www.euronews.com/green/2023/03/16/from-heating-swimming-pools-to-vertical-farms-data-centres-are-proving-useful-but-is-it-en">to heat water</a>.</p>
<p>Waste heat could also drive other kinds of air-conditioning systems, such as <a href="https://www.energy.gov/eere/amo/articles/absorption-chillers-chp-systems-doe-chp-technology-fact-sheet-series-fact-sheet">absorption chillers</a>, which can actually use heat as energy to support coolers through a series of chemical- and heat-transferring processes.</p>
<p>In either case, the energy needed to heat or cool something comes from heat that is otherwise wasted. In fact, waste heat from power plants could hypothetically support 27% of <a href="https://doi.org/10.1016/j.energy.2011.07.047">residential air-conditioning needs</a>, which would reduce overall energy consumption and carbon emissions.</p>
<p>Extreme heat can affect every aspect of modern life, and heat waves aren’t going away in the coming years. However, there are opportunities to harness extreme heat and make it work for us.</p><img src="https://counter.theconversation.com/content/210591/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>People aren’t the only ones harmed by heat waves. The hotter it gets, the harder it is for machines to keep their cool.Srinivas Garimella, Professor of Mechanical Engineering, Georgia Institute of TechnologyMatthew T. Hughes, Postdoctoral Associate, Massachusetts Institute of Technology (MIT)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2024762023-07-20T12:28:35Z2023-07-20T12:28:35ZA sculptor of wind explains how to make fiber dance far above city streets<figure><img src="https://images.theconversation.com/files/519873/original/file-20230406-22-dv2imt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">In 2018, Echelman's sculpture 'Earthtime 1.78 Madrid' premiered in the Spanish capital.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/an-art-installation-featuring-a-net-sculpture-of-layers-of-news-photo/918590464?adppopup=true">GettyImages</a></span></figcaption></figure><p><em><a href="https://arts.mit.edu/people/janet-echelman/">Janet Echelman</a> says she never set out to be a sculptor of wind. But if you have ever explored <a href="https://www.echelman.com/project/she-changes">Porto, Portugal</a>, walked the streets of <a href="https://www.echelman.com/earthtime-korea">Gwanggyo, South Korea</a>, or passed through <a href="https://www.echelman.com/project/west-hollywood">West Hollywood</a>, you might have seen her massive iridescent sculptures of fiber floating above cities and the millions of people in them. Working closely with engineers, Echelman has spent the past 26 years of her career producing sculptures that rival the size of skyscrapers.</em> </p>
<p><em>In March, Echelman spoke at the 2023 <a href="https://www.imaginesolutionsconference.com/">Imagine Solutions Conference</a> in Naples, Florida, about her journey to becoming a sculptor, her creative process and how her sculptures have forever changed the landscapes of the cities where they ripple, dance and billow in the wind.</em></p>
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<figcaption><span class="caption">Janet Echelman speaks at the 2023 Imagine Solutions Conference.</span></figcaption>
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<p><strong>What inspired you to create this type of art?</strong></p>
<p>I began my career as a painter. In 1997, I traveled to India as a Fulbright scholar and planned to give exhibitions around the country. I had my paints and brushes shipped to India from the U.S., but they never arrived. As the deadline for the show loomed, I had to come up with something fast. In Mahabalipuram, the Indian fishing village where I was staying, I would watch the fishermen work and reel in their mounds of netting on the beach at the end of each day. One day, it occurred to me that those nets would make excellent material for sculptures. By the end of my Fulbright year, I had created an entire series of these netted sculptures with the fishermen, called <a href="https://static1.squarespace.com/static/5bcf71640cf57d7e684e11bd/t/5c1966b78985836efb599fe2/1545168569303/Bellbottoms.pdf">the Bellbottom Series</a>, named after the popular bell-bottom pants. </p>
<p>I’ve been working to develop and refine this visual language ever since. It’s an ever-evolving challenge to go from making handmade nets on the beach with fishermen in India to creating works the scale of one or two city blocks attached to skyscrapers.</p>
<p><strong>How do you approach the engineering side of your art? How are these pieces constructed, especially given their large scale?</strong></p>
<p>Every piece is planned out digitally first. The first sketches are very simple – it’s just me with a pencil. </p>
<p>But the final design in our studio is a complete digital color 3D model. We can see how the sculpture sits in space and how it attaches to everything around it. We’re able to move around the three-dimensional site to see the work from all sides. </p>
<p>My team and I have engaged in a decade of development of original computer software to do soft-body modeling of our sculptures, which allows us to design our 3D netted forms while understanding the constraints of our craft, showing response to the forces of gravity and wind.</p>
<p>Every element – every line of twine, and every knot – is modeled in terms of its thickness, stiffness, weight and density. So it’s actually quite an endeavor to analyze such unusual structures that are both porous and fluidly moving. This is not the standard – building departments typically analyze solid buildings made of things they know, like steel and concrete – so this is really pushing everyone to work in new ways.</p>
<p>In terms of the physical construction, my sculptures appear delicate yet are incredibly strong. They have to be able to withstand winds of a Category 5 hurricane. We achieve that by using highly engineered materials, including a fiber that NASA used for the Mars Rover called <a href="https://www.sciencedirect.com/topics/chemistry/ultra-high-molecular-weight-polyethylene">ultrahigh-molecular-weight polyethylene</a>, which is custom-braided into structural ropes. We use a variety of other fibers to create the braided twine for the soft layers of each sculpture. </p>
<p>The ropes are then all hand-spliced together with methods that have been used for hundreds of years to construct boats in the maritime industry. These are old human technologies passed down from generation to generation. </p>
<p>Once we have these knotted net panels, we incorporate different colors to create patterns within the work. These panels are then attached to rope structures and usually lifted into space using cranes. My team pulls them into tension so that they can withstand immense forces of nature. </p>
<p><strong>What was the hardest sculpture to create from a technical standpoint, and why?</strong></p>
<p>My commission for the <a href="https://www.echelman.com/st-petersburg-fl">St. Petersburg pier</a> in Florida titled “Bending Arc” was challenging, because it needed to withstand a Category 5 hurricane – and yet we did it. There’s <a href="https://www.wtsp.com/video/news/local/bending-arc-at-st-pete-pier-dazzles-viewers-as-hurricane-ian-moves-through-florida/67-3583713f-164d-46e2-909e-60ccf0c3132d">footage of it during Hurricane Ian</a>, and it was just dancing beautifully. </p>
<p>Hurricane testing starts in the design stages. Our detailed digital models are tested and analyzed for their capacity to withstand certain forces of wind, which, for public safety reasons, is required in order to obtain a building permit. My sculptures have to satisfy the same requirements as a skyscraper, and they can withstand the same forces as any major building. </p>
<p><strong>What are you currently working on that you’re excited about?</strong></p>
<p>I am excited to continue to explore the relationship between dance and art. In 2014, <a href="https://www.echelman.com/project/dance-collaboration-stuttgart-germany-2014">I collaborated with the Stuttgart Ballet in Germany</a> to create sculptures that dancers could interact with in their performances. </p>
<p>Since then I have worked with a choreographer and engineer at Princeton University to create a sculpture that the dancers actually enter into and interact with. Their movements cause the sculpture to move and appear as if it were a dancer itself at a larger scale. I see it as an exploration of our planet and its climate. It illustrates how the Earth and human beings are always mutually influencing one another – and yet we are not equals. </p>
<p><strong>What do you hope your art evokes in people?</strong></p>
<p>It’s important to me that each person can create their own meaning from art. They are the expert in their own experience. </p>
<p>If my work offers a moment of contemplation and allows you to feel a sense of calm and your own interconnection with the wind, sun, people and city, then that’s all I could hope for. I like how complete strangers often start talking to each other underneath the sculptures. Our cities are made up of straight lines and hard edges and my sculptures offer something completely different – they are soft and adaptable, yet they’re the same scale as skyscrapers. </p>
<p>If my art prompts people to contemplate that the world can be built in a completely different way than it always has been, if it opens up questions, then that is the most an artist could ever hope to do.</p><img src="https://counter.theconversation.com/content/202476/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Janet Echelman does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Artist Janet Echelman explains how she collaborates with engineers to create massive sculptures that have changed city landscapes and inspired people around the world.Janet Echelman, Mellon Distinguished Visiting Artist, Massachusetts Institute of Technology (MIT)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2071682023-07-14T12:47:39Z2023-07-14T12:47:39ZEmpty office spaces can be converted to residential buildings – but it won’t be affordable<figure><img src="https://images.theconversation.com/files/534137/original/file-20230626-23-hhuczo.jpg?ixlib=rb-1.1.0&rect=0%2C3%2C2121%2C1406&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Many office buildings have been left empty since the start of the COVID-19 pandemic.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/low-angle-view-of-skyscrapers-in-london-royalty-free-image/1405678211?phrase=building">Gary Yeowell/DigitalVision via Getty Images</a></span></figcaption></figure><p>Since the COVID-19 pandemic began, <a href="https://www.pewresearch.org/short-reads/2023/03/30/about-a-third-of-us-workers-who-can-work-from-home-do-so-all-the-time/">more companies have offered remote work options</a> for their employees, or have even <a href="https://www.forbes.com/sites/bryanrobinson/2022/02/01/remote-work-is-here-to-stay-and-will-increase-into-2023-experts-say/?sh=383f0f5d20a6">switched to working entirely remotely</a> – leaving empty office buildings a new fixture in many cities. In July 2023, Boston’s <a href="https://www.bostonglobe.com/2023/07/10/business/wu-administration-will-offer-tax-breaks-turn-office-buildings-into-housing/">Planning and Development Agency announced</a> a pilot program to offer incentives to building developers who convert office buildings to residential housing.</p>
<p>As <a href="https://www.ccee.iastate.edu/directory/focus-areas/profile/jzbaker/">engineers</a> <a href="https://scholar.google.com/citations?user=zi8F33cAAAAJ&hl=en">who study buildings</a>, we wanted to know if these empty spaces could be converted to residential buildings, and what hurdles developers would face. </p>
<p>While converting office buildings to multi-family residential involves many considerations – including zoning codes, real estate values and structural issues – certain buildings may be good candidates for this type of conversion. Here’s what it would take to remodel these spaces. </p>
<h2>Redefining space</h2>
<p>First off, the building owners wouldn’t need to make any major structural changes to convert an office building to a residential building. Most office buildings are designed so that the tenants can easily <a href="https://www.ny-engineers.com/blog/shell-and-core-construction">build out the space</a> to suit their needs. This means they can put up walls, take power where they need, and select finishes like flooring, paint and lighting.</p>
<p>With a conversion to multi-family residential, the shell and structural elements of the building would remain, while the building owners could add or move walls to create individual apartments. The costs for this interior remodeling would depend on the <a href="https://www.build-review.com/high-end-finishes-and-materials-you-need-for-your-dream-home/">how fancy things like the countertops and light fixtures are</a>. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/-7EG4d-W4W8?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Proper daylighting in a dwelling or office provides a host of benefits.</span></figcaption>
</figure>
<p>But remodelers would also need to consider nonstructural building features, like windows. Windows determine the distribution of natural light in each <a href="https://doi.org/10.1016/j.enbuild.2016.02.026">residential unit</a>. Narrower office buildings with more area along the perimeter – and therefore more opportunity for viewing windows – would transition more easily to residential than deep, rectangular-shaped <a href="https://doi.org/10.1016/j.sleh.2017.03.005">office buildings</a>. No one wants to live in a <a href="https://www.reddit.com/r/Denver/comments/xg7elq/you_thought_slot_homes_were_bad_check_out_the/">home with no daylight</a>.</p>
<h2>Electricity, fire alarm and telecommunications</h2>
<p>Residential and commercial buildings have <a href="https://doi.org/10.1109/ECCE.2010.5618423">different electricity needs</a>. Residential buildings have <a href="https://www.siliconvalleypower.com/residents/save-energy/appliance-energy-use-chart">kitchen appliances</a> that require lots of power, but office buildings use more computers, projectors and copy machines – meaning the electrical load would likely be about the same. Office and residential buildings also have similar power needs for <a href="https://www.ies.org/standards/lighting-library/">lighting</a>. </p>
<p>The electrical load from heating and air conditioning would depend on the type of systems used. While the main electrical service of an office building might be an OK size for a residential building, remodelers would need to add a <a href="https://www.eaton.com/us/en-us/products/low-voltage-power-distribution-control-systems/loadcenters/load-center-fundamentals.html">subpanel</a> to each residential unit. U.S. code requires that all residents have “<a href="https://codes.iccsafe.org/s/ISEP2018/national-electrical-code-nec-solar-provisions/ISEP2018-NEC-Sec240.24">ready access</a>” to the circuit breakers or fuses supplying their unit. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/534142/original/file-20230626-4425-72bc8a.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Two floor plans, one shows an apartment layout with living room, kitchen, two bedrooms and a bathroom, while the other shows an office with bathrooms, an atrium and many individual offices" src="https://images.theconversation.com/files/534142/original/file-20230626-4425-72bc8a.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/534142/original/file-20230626-4425-72bc8a.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=261&fit=crop&dpr=1 600w, https://images.theconversation.com/files/534142/original/file-20230626-4425-72bc8a.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=261&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/534142/original/file-20230626-4425-72bc8a.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=261&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/534142/original/file-20230626-4425-72bc8a.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=327&fit=crop&dpr=1 754w, https://images.theconversation.com/files/534142/original/file-20230626-4425-72bc8a.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=327&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/534142/original/file-20230626-4425-72bc8a.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=327&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Residential units, left, and commercial units, right, use space differently and have different electrical, HVAC and plumbing needs.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Typical_apartment_floor_plan_FOCSA_Building.jpeg">Osvaldo valdes/Wikimedia Commons and Aushist/Wikimedia Commons</a></span>
</figcaption>
</figure>
<p>Building owners would also need to add more fire alarm devices, since residential buildings have more rooms. They might need to revise the internet, telephone and cable systems, as well, to make sure each residential tenant has access to these services.</p>
<p>Though expensive, these electrical revisions are possible. The biggest hurdles would be adding the subpanels and metering to figure out <a href="https://doi.org/10.1016/j.scs.2022.104250">how much each unit uses</a>.</p>
<h2>Heating, ventilation and air conditioning</h2>
<p>While commercial buildings usually have centralized HVAC systems, residential buildings need separate HVAC systems and controls for each residential unit. That being said, mid-rise and high-rise apartment buildings often use a centralized HVAC system with <a href="https://mepacademy.com/how-a-variable-air-volume-vav-system-works/">variable air volume units</a> in <a href="https://doi.org/10.1016/j.enbuild.2019.109429">each zone</a>. Variable air volume units work together with a central air handling unit that supplies a constant airflow. Each variable air volume unit then adjusts the air flow for its specific zone. Each smaller apartment would be a zone, but some larger apartments may need multiple zones. </p>
<p>Residential buildings typically have a smaller HVAC load than office buildings, meaning the existing HVAC system would be larger than needed for residential reuse. Oversized air conditioning systems often have humidity problems – add to that the fact that residential tenants <a href="https://www.apartments.com/blog/how-to-deal-with-home-humidity">create more humidity</a> from showering, doing laundry and cooking. The way to <a href="https://hghomeinspection.com/reduce-humidity-in-the-home/">mitigate humidity</a> here is through <a href="https://doi.org/10.4028/www.scientific.net/AMM.680.524">additional exhaust fans</a>. Variable air volume units would also help keep the extra humidity under control. Building owners would need to pay for these additions, as well as ductwork remodeling. </p>
<h2>Plumbing and fire protection</h2>
<p>In office buildings, most <a href="https://bsesc.energy.gov/energy-basics/basics-core-plumbing-layout">plumbing is centralized</a>, often in the building’s core. For instance, bathrooms tend to be grouped together and located in the same spot on each floor. However, in residential buildings, <a href="https://trusteyman.com/blog/how-plumbing-works-in-apartment-buildings/">plumbing is distributed throughout</a>. Each unit typically has its own bathroom and kitchen, and each requires drinking water and sanitary sewer. </p>
<p>The biggest issues here would be <a href="https://doi.org/10.1016/j.scs.2015.05.007">the service sizes</a> – or how large the pipes serving the building are – and the interior plumbing system. The <a href="https://doi.org/10.1002/j.1551-8833.1966.tb01643.x">service sizes for water</a> and sewer in an office building may not be big enough for residential uses. This would depend on <a href="https://www.weekand.com/home-garden/article/plumbing-code-requirements-18060405.php">local codes</a> and the number of plumbing fixtures. It’s likely that the pipe for a <a href="https://up.codes/viewer/iowa/upc-2018/chapter/7/sanitary-drainage#7">sewer utility connection</a> would need to be larger for an apartment building than for an office building. Also, the <a href="https://www.youtube.com/watch?v=qZ4HTmibt1g">interior plumbing system</a> would need a remodel to serve each residential unit. </p>
<p>Reworking the plumbing for water should be possible. However, reworking the <a href="https://codes.iccsafe.org/content/IPC2018/chapter-7-sanitary-drainage">sanitary sewer system</a> would be much more difficult, especially on upper floors. Gravity makes things run downhill, and longer horizontal pipes need more vertical drop to keep things flowing in the right direction. This remodel would require new <a href="https://www.h2ouse.org/pipe-chase/">plumbing chases</a> – vertical cavities that pipes run in – to accommodate the sanitary sewer and vent piping needs. Adding these chases would likely require <a href="https://doi.org/10.1016/j.procir.2023.03.008">core drilling</a> of floors. If the owner wanted to invest the money, it would be doable – but expensive.</p>
<p>The <a href="https://www.nfpa.org/News-and-Research/Publications-and-media/Blogs-Landing-Page/NFPA-Today/Blog-Posts/2021/03/26/Sprinkler-System-Basics-Types-of-Sprinkler-Systems">fire sprinkler system</a> would likely need revisions once the new walls go up, but the size of the pipe bringing water to the sprinkler system should be pretty close to the right size.</p>
<h2>New life for vacant buildings is doable but not easy</h2>
<p>No one wants to see <a href="https://www.npr.org/2023/05/16/1174938708/commercial-real-estate-property-offices-work-from-home-remote-work">office buildings sitting vacant</a>, as vacant buildings can <a href="https://communityprogress.org/blog/how-vacant-abandoned-buildings-affect-community/">diminish surrounding real estate values</a>. Converting an office building to a multi-family residential occupancy is possible. It would, however, not be cheap.</p>
<p>But office buildings that are due for a remodel or upgrade anyway could be great candidates for this type of reinvention. If the building systems – HVAC, plumbing, electrical – are due for replacement, the project becomes more cost effective. With <a href="https://www.jchs.harvard.edu/americas-rental-housing-2022">demand for rental units outpacing growth in new supply</a>, and many cities like <a href="https://www.axios.com/local/san-francisco/2023/04/06/san-francisco-office-housing-conversions">San Francisco</a> and <a href="https://www.bostonglobe.com/2023/07/10/business/wu-administration-will-offer-tax-breaks-turn-office-buildings-into-housing/">Boston</a> offering incentives to convert, there is potential here. For someone with a creative vision and a building in the right location, this could be a successful and innovative project.</p><img src="https://counter.theconversation.com/content/207168/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>With many employers switching to remote work, two engineering experts explain the feasibility of converting office buildings to residential spaces.Jenny Baker, Teaching Professor in Civil, Construction and Environmental Engineering, Iowa State UniversityLeah Mo, Assistant Professor of Civil, Construction and Environmental Engineering, Iowa State UniversityLicensed as Creative Commons – attribution, no derivatives.