Tag: travel and transportation

Distracted driving on the rise, but rather than the problem, expert says technology could be the solution

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In the digital age, an increased desire for constant online connection has created safety hazards for drivers on the road. It’s especially top of mind during the month of April, which is Distracted Driver Awareness Month, but Virginia Tech Transportation Institute (VTTI) researcher, Charlie Klauer says that technology can also be part of the solution.

According to VTTI, the top distractions are inattention due to fatigue and texting, particularly by inexperienced drivers . Klauer, a research scientist and leader within the Division of Vehicle, Driver, & System Safety, says the emergence of modern technology has certainly had an impact on our driver experience and safety. Klauer explains that while technology is a distraction, it can also be a part of the solution through tools such as car play, in which drivers can answer a call hands-free.

“As human factors researchers, it is imperative that we improve the design of the in-vehicle interfaces to allow drivers to interact with cellular technologies in the safest way possible,” says Klauer. “Any interactions that reduce eyes off the forward roadway and physical manipulation of the phone will improve safety.”

Although texting while driving is illegal and a primary offense in Virginia and many other states, it remains a key challenge in driving safety. Klauer explains that these laws are crucial and must be enforced.

“While passing hands-free laws is certainly an important step, it will also require that these laws are enforced by police officers, that fines and violations are significant enough to warrant behavior change, and technological solutions exist to allow drivers to remain connected while remaining as safe as possible,” says Klauer.

Texting while driving isn’t the only distraction people face. “Other examples include eating, reaching for objects, interacting with an infotainment system, etcetera,” says Klauer.

Klauer has also researched the effect that age has on distraction on risks. Her findings show that younger groups are at higher risk.

“Our younger age groups are far more affected by secondary task engagement. These younger age groups certainly include teenage drivers (ages 16-20) but also young adults,” says Klauer. “Recent research has shown that drivers between 21-29 also have very high crash rates associated with many secondary tasks, especially when using wireless devices.”

Klauer says following safety recommendations is vital to keeping both you and other drivers on the road safe.

Read more from the Virginia Tech Transportation Institute about distracted driving here.

About Klauer

Charlie Klauer is a research scientist and leader of the Training Systems Group in the Division of Vehicle, Driver, & System Safety at the Virginia Tech Transportation Institute. She is also an associate professor in the Industrial and Systems Engineering Department in the College of Engineering and researches Human Factors Engineering and Ergonomics. Klauer has been working in transportation research since 1996.

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Virginia Tech

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April 14, 2023
New SLAC-Stanford Battery Center targets roadblocks to a sustainable energy transition

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Newswise — Menlo Park, Calif. – The Department of Energy’s SLAC National Accelerator Laboratory and Stanford University today announced the launch of a new joint battery center at SLAC. It will bring together the resources and expertise of the national lab, the university and Silicon Valley to accelerate the deployment of batteries and other energy storage solutions as part of the energy transition that’s essential for addressing climate change.

A key part of this transition will be to decarbonize the world’s transportation systems and electric grids – to power them without fossil fuels. To do so, society will need to develop the capacity to store several hundred terawatt-hours of sustainably generated energy. Only about 1% of that capacity is in place today.

Filling the enormous gap between what we have and what we need is one of the biggest challenges in energy research and development. It will require that experts in chemistry, materials science, engineering and a host of other fields join forces to make batteries safer, more efficient and less costly and manufacture them more sustainably from earth-abundant materials, all on a global scale.

The SLAC-Stanford Battery Center will address that challenge. It will serve as the nexus for battery research at the lab and the university, bringing together large numbers of faculty, staff scientists, students and postdoctoral researchers from SLAC and Stanford for research, education and workforce training.

“We’re excited to launch this center and to work with our partners on tackling one of today’s most pressing global issues,” said interim SLAC Director Stephen Streiffer. “The center will leverage the combined strengths of Stanford and SLAC, including experts and industry partners from a wide variety of disciplines, and provide access to the lab’s world-class scientific facilities. All of these are important to move novel energy storage technologies out of the lab and into widespread use.”

Expert research with unique tools

Research and development at the center will span a vast range of systems – from understanding chemical reactions that store energy in electrodes to designing battery materials at the nanoscale, making and testing devices, improving manufacturing processes and finding ways to scale up those processes so they can become part of everyday life.

“It’s not enough to make a game-changing battery material in small amounts,” said Jagjit Nanda, a SLAC distinguished scientist, Stanford adjunct professor and executive director of the new center, whose background includes decades of battery research at DOE’s Oak Ridge National Laboratory. “We have to understand the manufacturing science needed to make it in larger quantities on a massive scale without compromising on performance.”

Longstanding collaborations between SLAC and Stanford researchers have already produced many important insights into how batteries work and how to make them smaller, lighter, safer and more powerful. These studies have used machine learning to quickly identify the most promising battery materials from hundreds made in the lab, and measured the properties of those materials and the nanoscale details of battery operation at the lab’s synchrotron X-ray facility. SLAC’s X-ray free-electron laser is available, as well, for fundamental studies of energy-related materials and processes.

SLAC and Stanford also pioneered the use of cryogenic electron microscopy (cryo-EM), a technique developed to image biology in atomic detail, to get the first clear look at finger-like growths that can degrade lithium-ion batteries and set them on fire. This technique has also been used to probe squishy layers that build up on electrodes and must be carefully managed, in research performed at the Stanford Institute for Materials and Energy Sciences (SIMES).

Nanda said the center will also focus on making energy storage more sustainable, for instance by choosing materials that are abundant, easy to recycle and can be extracted in a way that’s less costly and produces fewer emissions.

A unique collaboration in the heart of Silicon Valley

Battery Center Director Will Chueh, an associate professor at Stanford and faculty scientist at SLAC, emphasized that the center is located in the middle of Silicon Valley’s entrepreneurial culture, two miles from the Stanford campus and a short walk away from large, world-class scientific facilities that only a national lab can provide. This generates advantages that would be impossible for any single partner to achieve, including outstanding educational and training opportunities for Stanford students and postdocs that will play an outsized role in shaping the next generation of energy researchers.

“There’s no other place in the world,” Chueh said, “where all of this comes together.”

A pilot project for the center began in 2020 with two battery laboratories in SLAC’s Arrillaga Science Center where Stanford students and postdoctoral researchers have been synthesizing battery materials and evaluating devices.

The center is operated by SLAC’s Applied Energy Division and Stanford’s Precourt Energy Institute. Major funding for battery research at SLAC comes from the DOE Office of Science and Office of Energy Efficiency and Renewable Energy. SLAC’s Stanford Synchrotron Radiation Lightsource (SSRL) and Linac Coherent Light Source (LCLS) X-ray free-electron laser are DOE Office of Science user facilities.

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SLAC National Accelerator Laboratory

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April 13, 2023
Prepare for Landing: Making Airports More Efficient

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Newswise — WASHINGTON, March 28, 2023 – Air traffic is a significant and complex problem. Near misses between passenger planes on runways have been making headlines lately and raising safety concerns as airports try to accommodate more travelers in the wake of COVID-19. Also, as any disgruntled air traveler knows, a single aircraft’s late arrival at a busy airport can trigger an avalanche effect and cause a series of subsequent delays.

In Chaos, from AIP Publishing, a team of scientists from Spain and Argentina presented an original oscillating short-term memory model, with just two parameters, to study the dynamics of landing events at 10 major European airports. The model can estimate how landing volumes will influence those in consecutive hours – a critical ability given airport capacity constraints and external events that cause landing delays.

Altogether, the model demonstrates that statistical analyses of hourly plane landing volumes can yield valuable insights into airport operations.

“Characterizing chains of landing delay events, especially quantifying the temporal scale, is key for evaluating an airport’s operational performance,” said author Felipe Olivares. “If directly identifying interactions is not possible, a solution is to analyze the signatures they leave in time series as representative of the system’s aggregated dynamics. The main idea [of the study] is to use statistical physics tools to obtain insights about airport operations when only macroscale information, the hourly landing volume, is available.”

One of the model’s parameters represents the correlation between consecutive hours in landing volume as a metric of an airport’s landing operations efficiency.

“This could also help assess the evolution of a facility’s efficiency, understood as the capacity of handling a given traffic volume while generating minimal interaction between aircraft,” said Olivares.

The study also examined the differences between dynamics before and after the peak of COVID-19, determining that the landing flow became more random post-pandemic. That means consecutive hours in landing flow were less correlated. But this was not only caused by reduced traffic because of travel restrictions: it also might reflect a change in interactions between aircraft.

A first of its kind, the study showcases how, via statistical physics, macroscale aeronautical data analysis can reveal information on microscale dynamics.

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The article “Markov-modulated model for landing flow dynamics: An ordinal analysis validation” is authored by F. Olivares, L. Zunino, and M. Zanin. It will appear in Chaos on March 28, 2023 (DOI: 10.1063/5.0134848). After that date, it can be accessed at http://aip.scitation.org/doi/full/10.1063/5.0134848.

ABOUT THE JOURNAL

Chaos is devoted to increasing the understanding of nonlinear phenomena in all areas of science and engineering and describing their manifestations in a manner comprehensible to researchers from a broad spectrum of disciplines. See https://aip.scitation.org/journal/cha.

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American Institute of Physics (AIP)

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March 28, 2023
11 ways to improve airlines for customers
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Newswise — COLUMBIA, Mo— The name of the game is customer satisfaction, especially in the airline industry where companies are constantly jockeying for business by promising better service than their competitors. Now a professor at the University of Missouri has used artificial intelligence to sort through thousands of customer reviews and identify where airlines are falling short.

Sharan Srinivas, an assistant professor with a joint appointment in the Department of Industrial and Systems Engineering and the Department of Marketing, used AI to analyze nearly 400,000 unique, publicly available customer reviews of six airline companies throughout the United States. After sorting through the information, he developed algorithms that identified the most common themes discussed in the reviews and then determined the customer’s sentiment (positive or negative) toward each of the identified themes, allowing airlines to potentially gain a better understanding of their customers’ perspective and experience.

The results showed most of the negative feedback involved lost luggage, uncomfortable seating and flight cancellations; while customers felt most positively about in-flight entertainment, ground and cabin staff service and service in first- and business-class seating.

Based on this feedback, Srinivas posited 11 recommendations to improve the customer experience:
1. Implement more flexible seating arrangements to improve comfort.
2. Automate the disinfecting process for bathrooms in the plane.
3. Redesign overhead baggage bins.
4. Implement a more personalized cabin environment through seat height and temperature adjustments capabilities.
5. Use analytical models to optimize flight schedules and time buffer between flights.
6. Use an artificial intelligence-based approach to monitor equipment health.
7. Introduce a more flexible booking policy (i.e., no cancellation charge, no change fee, upfront information about costs).
8. Provide ticketing agents with better task clarifications, performance-based feedback and social praise to better improve morale and interactions with customers.
9. Install more accurate luggage tracking systems by using RFID tags in lieu of regular barcode tags.
10. Provide more frequent and automated baggage related updates to passengers’ phones.
11. Use biometrics and blockchain technology to remove the need to present several identification documents at multiple checkpoints. This would eliminate the need for passengers to show a boarding pass, passport and ID.
Srinivas said airlines can use this information to determine their next steps as a company.

“The ultimate goal is to help inform these airlines about what the customer is actually thinking,” Srinivas said. “It’s impossible to hear every customer and potential customer’s voice, especially for bigger airlines, but our software and recommendations will significantly assist the airlines in thinking about things from a consumer perspective.”

Srinivas was inspired to pursue this research by an incident in 2017, in which a United Airlines security representative dragged a passenger off a plane when he refused to leave because the flight was overbooked. United Airlines officials said they chose the passenger at random, yet the amount of outrage that poured in via customer review and on social media was staggering. Consequently, it was challenging for United Airlines to sift through all the customer feedback. Srinivas said this study’s AI software would allow companies like United Airlines to sort through customer feedback and more quickly respond to issues when they arise.

“Using our proposed approach could allow companies to digest textual information in a much more automated and streamlined manner,” Srinivas said. “Without an automated process, it would be much more challenging and time consuming to look at each individual review and come away with something that airlines can use to improve their business.”

While stakeholders and employees may have a better understanding of how the business works, Srinivas said that when it comes to the product — air travel in this case — knowing your customers is key.

“The users of a product are the ones that can give you the best insight on what needs to be improved,” Srinivas said. “They are the target audience. They are the ones using the product with limited bias and there’s a lot of untapped insight in what they are saying.”

Srinivas has used different versions of artificial intelligence to track customer approval in many different industries, including insurance, adaptive clothing and colleges. Srinivas said it can be used to interpret doctor’s notes and patient reviews as well.

“Passenger intelligence as a competitive opportunity: unsupervised text analytics for discovering airline-specific insights from online reviews” contains more details on all 11 recommendations and was published in Annals of Operation Research.

Editor’s note: Sharan Srinivas has a joint appointment in the MU College of Engineering and the Trulaske College of Business.
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University of Missouri, Columbia

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March 24, 2023
Fact-checking the reporting of the explosion in East Palestine, Ohio
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Five days after a Norfolk Southern train carrying vinyl chloride derailed and exploded near the Ohio-Pennsylvania border, crews ignited a controlled burn of toxic chemicals to prevent a much more dangerous explosion. Local residents of East Palestine, Ohio are wondering whether returning to the area is really safe. In a report from television station WXBN in Youngstown, Ohio, it was disclosed that additional toxic chemicals have been discovered in the area. A comment made by Sil Caggiano, a hazardous materials specialist, was included in the WXBN report. Caggiano said that “We basically nuked a town with chemicals so we could get a railroad open.” The quote has been shared by thousands on social media. Christopher M. Reddy, a Senior Scientist at the Department of Marine Chemistry and Geochemistry at Woods Hole Oceanographic Institution cautions that this statement may be hyperbole.

“Do not let the ‘doom and gloom’ overwhelm you,” says Reddy. In response to the Caggiano’s “nuked a town” statement, Reddy says it is “totally irresponsible. A very different situation when perceived by the public.”

Reddy’s comment on the reporting of the incident:

I would caution that the outcomes and scenarios available on Wikipedia are often overgeneralized and lack nuance. I don’t wish to downplay this accident at all. Very different situation. It is very hard to predict the short and long-term impacts of any chemical release with great certainty, but I don’t foresee with the knowledge in hand, significant long-term impacts. All of these chemicals are relatively short-lived and unlikely to persist for many months, and they have a low affinity to bioaccumulate in human and animal tissue.”

Reddy recommends the following for local residents:
1. Remain cautious
Mark Jones, a retired industrial chemist has this to say…

The chemicals, now four, are all dangerous in multiple ways. They can be acutely toxic, chronically toxic and they are all flammable. The controlled burn takes flammable materials to more benign materials. In the case of vinyl chloride, a product of combustion is hydrochloric acid, itself dangerous but not flammable.

The comment about a “more dangerous explosion” is a bit misleading. There is a risk to those attempting to clean up the site if there is a reservoir of flammable material. Reducing that risk is one of the reasons to do a controlled burn. There are many ways to do a controlled burn and I don’t know exactly what was done here.

Two of the materials, vinyl chloride and isobutylene, are quite volatile. Isobutylene handles approximately like butane, the stuff in a lighter. It is a liquid under just a little bit of pressure. Release the pressure and it becomes a gas. Vinyl chloride is similar. When released, both become a gas. They should not persist on the site. They should be swept away in the air.

The other two materials, ethylene glycol monobutyl ether and ethylhexyl acrylate, are higher boiling liquids. Both are flammable. The controlled burn of these materials should destroy them and make only carbon dioxide and water.

Note to Journalists/Editors: The expert quotes are free to use in your relevant articles on this topic. Please attribute them to their proper sources.
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Newswise

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February 14, 2023
Helping transit agencies visualize the transition to electric bus fleets

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Newswise — The transit industry is rapidly moving toward battery electric bus fleets because of the environmental and financial benefits they offer. As electric vehicles become more prevalent, transit agencies have several questions to consider: What is the most cost-effective and equitable way to make the transition to electric buses? How can the buses’ charging needs be incorporated into the existing city power grid? In which parts of the city should electric buses be introduced first, and what impacts will all this have on transit operations? A new modeling and visualization tool can help agencies answer those questions.

With funding from a National Institute for Transportation and Communities (NITC) “Translate Research to Practice” grant, a team of University of Utah (UU) researchers led by Xiaoyue Cathy Liu and Jianli Chen have created a model—a “bi-objective optimization framework”—which takes both cost and environmental equity into consideration, helping transit agencies achieve their desired environmental and public health-related outcomes in the most cost-effective way. The flexible framework is a helpful tool for doing cost-benefit analysis on a range of transit-related objectives. The research team also created two products to help transit agencies use the model:

WHAT DO THESE TOOLS DO?

The bi-objective optimization framework model allows transit operators, planners and decision-makers to explore the interdependency of an electric bus transit system and a city’s energy infrastructure, in both spatial and temporal dimensions with high resolution. It allows agencies to make short and long-term decisions based on their investment resources and strategic goals.

Building on that framework, the research team developed their prototype visualization tool, the BEB Explorer. BEB stands for battery-electric bus, and the visualization tool lets users test, visualize, and explore different BEB deployment scenarios given constraints of budget, bus schedules, routing, charging station locations, and other factors. The explorer includes an interactive map of routes and charging locations, with data tables that dynamically update. Also, users can zoom in and create overviews at different resolutions.

The guide offers step-by-step instructions to help practitioners implement the model for their own transit network, using their own customized data. From compiling the data, to running the model, to interpreting the results and setting up visualizations for presentations to assist with decision-making, the guide aims to make it easy for agencies to get the most out of this model.

WHY IS IT IMPORTANT?

Last year, we reported on the project team’s original research effort to roll out electric buses while improving air quality in high-pollution, low-income areas. Transit agency partners had this to say:

“We are making investments based on [Dr. Liu’s] recommendations, from the model and the tool, for five more high-powered chargers in our system…. You can optimize to a lot of different factors using her model. It’s a really good tool in that you can use it in multiple ways to make better business decisions for both your agency and the community.”

– Hal Johnson, Manager of Systems Planning and Project Development, Utah Transit Authority

“This research made me aware of always communicating and addressing equity issues, even in small projects. I’m working on implementing small electric community shuttle systems and this research was very relevant.”

– Project Specialist, Florida Department of Transportation

Building upon this body of work, Liu and Andy Hong of UU’s Department of City & Metropolitan Planning are also partnering with the Utah Transit Authority (UTA) to design a dynamic service with zero-emission transit vehicles to enhance service equity and efficiency for vulnerable populations. That effort is funded by a grant from the Federal Transit Administration (FTA)’s “Areas of Persistent Poverty” program, aimed at creating better transit for residents who have limited or no transportation options.

Project team members Gabrielius Kudirka, Xinyuan Yan, Sarah Kunzler, Yirong Zhou, Bei Wang and Xiaoyue Cathy Liu of UU presented their latest work on this topic at the 2023 annual meeting of the Transportation Research Board (TRB) in a poster session on Current Issues in Alternative Fuels and Technologies. Check out their poster, Enable Decision Making for Battery Electric Bus Deployment Using Robust High-Resolution Interdependent Visualization (PDF) or read the full research paper (PDF).

This research was funded by the National Institute for Transportation and Communities, with additional support from the University of Utah and Rocky Mountain Power.

ABOUT THE PROJECT

Enabling Decision-Making in Battery Electric Bus Deployment through Interactive Visualization

Xiaoyue Cathy Liu and Jianli Chen, University of Utah

RELATED RESEARCH

To learn more about this and other NITC research, sign up for our monthly research newsletter.

The National Institute for Transportation and Communities (NITC) is one of seven U.S. Department of Transportation national university transportation centers. NITC is a program of the Transportation Research and Education Center (TREC) at Portland State University. This PSU-led research partnership also includes the Oregon Institute of Technology, University of Arizona, University of Oregon, University of Texas at Arlington and University of Utah. We pursue our theme — improving mobility of people and goods to build strong communities — through research, education and technology transfer.

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Portland State University

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February 10, 2023
Attributing the rising costs of groceries to “price gouging” is not accurate

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Fact Check By:
Craig Jones, Newswise

Truthfulness: Mostly False

Claim:

Grocery stores need to be brought to heel over food prices. This isn’t ‘inflation’ because it isn’t caused by monetary oversupply. It’s just price gouging and we know that because we can literally see that they’re all reporting surplus profits.

Claim Publisher and Date: Twitter user emmy rākete among others on 2023-01-21

On social media, complaints regarding the rising costs of groceries are trending. It’s no surprise after all, the price of groceries has gone up around 13% compared to last year. According to the data from the Labor Department, the price of fruits and vegetables increased by 10.4 percent annually, while milk rose 15.2 percent and eggs soared 30.5 percent. Like other sectors of the economy, food prices are susceptible to supply chain complications and geopolitical unrest including the war in Ukraine. But some people have expressed their disdain for grocery store companies, accusing them of “price gouging” to increase their profits, which have been reaching exorbitant heights (corporate profits are at their highest levels in nearly 50 years, according to CBS MoneyWatch).

For example, this tweet shared by thousands blames the rising prices of groceries on retailers engaged in price gouging: “Grocery stores need to be brought to heel over food prices. This isn’t ‘inflation’ because it isn’t caused by monetary oversupply. It’s just price gouging and we know that because we can literally see that they’re all reporting surplus profits.”

Is putting the blame on grocery store managers for your rising costs of orange juice accurate? It’s not quite that simple. The claim of “price gouging” at the grocery store is misleading because of the complex nature of the grocery business. Professor Lisa Jack, School of Accounting, Economics and Finance and lead of the Food Cultures in Transition (FoodCiTi) research group at the University of Portsmouth explains…

Supermarket profits are complex and care should be taken with attributing them to any one cause. There are three main factors:

Commercial income, also known as suppliers payments or back margin, contributes heavily to supermarket profits. These payments and support from suppliers to the supermarket include volume discounts and marketing fees. These can represent as much as 7% of a supermarket’s income: bottom line profits can average around 1-2% of income. Primary producers are seeing rapidly increasing costs for all inputs and having been squeezed to breaking point over the last 20 years, have no choice but to increase the prices of their output. Similarly for processors, packagers, distributors and every other business supplying supermarkets. The supermarkets themselves claim to be fighting on behalf of consumers to be keeping prices down and there is evidence that they are refusing price increase requests, which implies that commercial income is still being maintained.

In the last few years, supermarkets have been increasing profits by cutting overhead costs at head offices and in support services. Counterintuitively, the only economy of scale they have is bargaining power – see above. All their activities, including large stores, increase the overhead costs which can be as much as 75% of their spend. A significant amount of recent ‘soaring profits’ come from job losses, which are not sustainable in the long run.

Since their emergence in the 1920s, the business model for supermarkets has been to sell basics at little or no profit relying on high volumes to break even. Profits come from enticing customers to buy at least one impulse, premium item of food and non-grocery items. 8 of the 10 best sellers in supermarkets are the cheaper (but still higher profit margin) alcohol, confectionery and snacks. Since the pandemic and the cost of living crisis hit, more of us are exchanging going out for buying in ready-meals, alcohol and other treats, and buying more of our non-grocery items from supermarkets. These are where the profits come from, and they are being taken away from other sectors. Unsurprisingly, the food businesses that have the highest margins are those that produce brands of alcohol, confectionery etc – ‘Big Food’.

Note to Journalists/Editors: The expert quotes are free to use in your relevant articles on this topic. Please attribute them to their proper sources.

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Newswise

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January 26, 2023
Comparing airfares instead of seat size fairer indicator of passenger carbon emissions

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Newswise — Allocating passenger aircraft emissions using airfares rather than travel class would give a more accurate idea of individual contributions, finds a study led by UCL.

Emissions calculators base their estimates on travel class, assuming that someone travelling in a higher class and therefore taking up more space on the plane is responsible for more emissions.

The study, published in Environmental Research Letters, describes how including airfares in calculations shows which passengers contribute the most revenue to the airline operating the aircraft, thereby allowing the plane to fly.

Although in general, premium (business) seats are more expensive than economy, the researchers found when looking at data that many late bookings in economy class, often made for business trips or by high income travellers, cost as much as, or more than, premium seats.

Lead author Dr Stijn van Ewijk (UCL Civil, Environmental & Geomatic Engineering) said: “The paper shows we should follow the money when calculating emissions of individual travellers, as it is revenue that decides whether an airline can operate a plane or not. Someone who has paid twice as much as a fellow traveller contributes twice as much to the revenue of the airline and should be allocated twice the emissions. The seat size of each travel class, which is currently used to allocate emissions, is only a rough approximation of how much passengers pay.”

The researchers say that using airfares to calculate passenger emissions would benefit efforts to address climate change by encouraging people on all budgets to find alternative modes of transport where possible. It would also increase estimates of corporate emissions because it allocates more to expensive late bookings, which are often made for business purposes.

Implementing a tax that is proportionate to the price of the ticket could make the total costs of flying fairer. People buying the most expensive tickets would pay the highest tax, encouraging them to seek alternatives.

Whilst taxes differ between countries, typically the rates are the same across each travel class. Travellers buying expensive tickets, who are more likely to have higher incomes, pay a relatively low tax and are not currently discouraged from flying.

Dr Van Ewijk added: “An equitable approach to reducing airline emissions should not just deter travellers who can only afford the cheapest early bookings but also the big spenders who bankroll the airline. By assigning emissions based on ticket prices, and taxing those emissions, we can make sure everyone pays their fair share, and is equally encouraged to look for alternatives.”

A ticket tax should also take into account the distance flown and the model and age of plane, which can indicate how polluting it is.

The authors used a dataset from the USA to test their fare-based allocation approach. They used the Airline Origin Survey database, which includes ticket fare data, origin and destination, travel class and fare per mile. From this, they calculated the distribution of ticket prices across all passengers on a typical flight.

Based on the price distribution, the authors allocated emissions to passengers, and compared the results with estimates from widely used emissions calculators. Since ticket prices vary strongly by time of booking, the emissions per passenger varied too, far more than on the basis of seat size and travel class.

Using an economic supply–demand model, the researchers estimated how a carbon tax on emissions would affect travellers, depending on whether the emissions the tax applied to were calculated from seat size and travel class, or the airfare. In all scenarios, a tax on emissions calculated from airfares had a more equitable effect because it reduced flying more evenly across income groups.

The researchers hope to effect policy change in calculating and taxing passenger emissions, to ensure travellers on all budgets are encouraged to seek other forms of transport where possible or consider how essential the journey is.

Notes to Editors

Stijn van Ewijk, Shitiz Chaudhary, Peter Berrill; Estimating passenger emissions from airfares supports equitable climate action will be published in Environmental Research Letters on Wednesday 25^th January, 12:00 UK time, 07:00 ET and is under a strict embargo until this time.

The DOI for this paper will be 10.1088/1748-9326/acaa48

Additional material

Graphs and figures from the paper

Credit: Dr Stijn Van Ewijk

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University College London

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January 25, 2023
An exploration of calibrating activity-based mobility demand of travelers with bounded rationality

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Newswise — Parameter calibration of the traffic assignment models is vital to travel demand analysis and management. As an extension of the conventional traffic assignment, boundedly rational activity-travel assignment (BR-ATA) combines activity-based modeling and traffic assignment endogenously and can capture the interdependencies between high dimensional choice facets along the activity-travel patterns. The inclusion of multiple episodes of activity participation and bounded rationality behavior enlarges the choice space and poses a challenge for calibrating the BR-ATA models. Till now, no formulation and solution approach for the parameter calibration of BR-ATA has hitherto been developed. To solve this problem, Dong Wang and Feixiong Liao formulated BR-ATA calibration as an optimization problem and used a simultaneous perturbation stochastic approximation method to solve it.

They published their study on January 20, 2023, in Communications in Transportation Research (https://doi.org/10.1016/j.commtr.2023.100092).

“In virtue of the multi-state supernetwork, we formulate the BR-ATA calibration as an optimization problem and analyze the influence of the two additional components on the calibration problem. Considering the temporal dimension, we also propose a dynamic formulation of the BR-ATA calibration problem. The simultaneous perturbation stochastic approximation algorithm is adopted to solve the proposed calibration problems. Numerical examples are presented to calibrate the activity-based travel demand for illustrations.”, says Dr. Feixiong Liao, a transportation scientist from the Urban Planning and Transportation Group at Eindhoven University of Technology (the Netherlands).

The BR parameter and activity participation affect the calibrations

The running times fall within [0.30, 0.40] hours when the BR parameter takes different values. Note that the ATA calibration problem needs more than 2 hours to reach the stopping condition. Regarding the influence of the number of activities, the running time decrease with the increase in the number of activities.

“We can conclude that the running times with the BR-related parameter falling within [0.05, 0.2] are relatively stable and shorter than that with a smaller parameter (i.e., 0.01 or ATA calibration problem). Besides, fewer activities always result in flows being concentrated in a specific period of time and link. The link congestion leads to more ATPs to equilibrate the OD demands.” Dong Wang, an associate professor at Qingdao University (China), explains.

Temporal and spatial dimension extensions to the BR-ATA calibration problem

The SPSA takes 8.2 hours to reach the stopping condition for the BR-ATA calibration problem in the Sioux Falls network and the calibrated demands approximate a priori values. Taking one home location for example, the study observes that the calibrated demand has a relative error of 0.01. For the BR-DATA calibration problem in the Sioux Falls network, the running time is 0.92 hours and the number of iterations is 647. All the calibrated demands approach a priori values. To further illustrate scalability in a larger network, the calibration of the BR-DATA model was carried out with the Eastern Massachusetts network. The SPSA takes more than 10 hours to complete 1000 iterations and the corresponding RMSN (a measurement of error) is as small as 0.06.

“The results demonstrate that the SPSA algorithm is feasible for the BR-ATA and BR-DATA calibration problems in sizable networks.”, Feixiong Liao says. “Nevertheless, a more effective algorithm is needed for large-scale real-world applications”, he adds.

The above research is published in Communications in Transportation Research (COMMTR), which is a fully open access journal co-published by Tsinghua University Press and Elsevier. COMMTR publishes peer-reviewed high-quality research representing important advances of significance to emerging transport systems. COMMTR is also among the first transportation journals to make the Replication Package mandatory to facilitate researchers, practitioners, and the general public in understanding and advancing existing knowledge. At its discretion, Tsinghua University Press will pay the open access fee for all published papers from 2021 to 2025.

##

About Communications in Transportation Research

Communications in Transportation Research publishes peer-reviewed high-quality research representing important advances of significance to emerging transport systems. The mission is to provide fair, fast, and expert peer review to authors and insightful theories, impactful advances, and interesting discoveries to readers. We welcome submissions of significant and general topics, of inter-disciplinary nature (transport, civil, control, artificial intelligence, social science, psychological science, medical services, etc.), of complex and inter-related system of systems, of strong evidence of data strength, of visionary analysis and forecasts towards the way forward, and of potentially implementable and utilizable policies/practices. Communications in Transportation Research is indexed in Scopus ten months after its launch.

Communications in Transportation Research is a fully open access journal. It is co-published by Tsinghua University Press and Elsevier, and co-sponsored by the State Key Laboratory of Automotive Safety and Energy (Tsinghua University) and China Intelligent Transportation Systems Association (ITS China). At its discretion, Tsinghua University Press will pay the open access fee for all published papers from 2021 to 2025.

About Tsinghua University Press

Established in 1980, belonging to Tsinghua University, Tsinghua University Press (TUP) is a leading comprehensive higher education and professional publisher in China. Committed to building a top-level global cultural brand, after 41 years of development, TUP has established an outstanding managerial system and enterprise structure, and delivered multimedia and multi-dimensional publications covering books, audio, video, electronic products, journals and digital publications. In addition, TUP actively carries out its strategic transformation from educational publishing to content development and service for teaching & learning and was named First-class National Publisher for achieving remarkable results.

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January 20, 2023
AI improves detail, estimate of urban air pollution

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Newswise — ITHACA, N.Y. – Using artificial intelligence, Cornell University engineers have simplified and reinforced models that accurately calculate the fine particulate matter (PM2.5) – the soot, dust and exhaust emitted by trucks and cars that get into human lungs – contained in urban air pollution.

Now, city planners and government health officials can obtain a more precise accounting about the well-being of urban dwellers and the air they breathe, from new research published December 2022 in the journal Transportation Research Part D.

“Infrastructure determines our living environment, our exposure,” said senior author Oliver Gao, the Howard Simpson Professor of Civil and Environmental Engineering in the College of Engineering at Cornell University. “Air pollution impact due to transportation – put out as exhaust from the cars and trucks that drive on our streets – is very complicated. Our infrastructure, transportation and energy policies are going to impact air pollution and hence public health.”

Previous methods to gauge air pollution were cumbersome and reliant on extraordinary amounts of data points. “Older models to calculate particulate matter were computationally and mechanically consuming and complex,” said Gao, a faculty fellow at the Cornell Atkinson Center for Sustainability. “But if you develop an easily accessible data model, with the help of artificial intelligence filling in some of the blanks, you can have an accurate model at a local scale.”

Lead author Salil Desai and visiting scientist Mohammad Tayarani, together with Gao, published “Developing Machine Learning Models for Hyperlocal Traffic Related Particulate Matter Concentration Mapping,” to offer a leaner, less data-intensive method for making accurate models.

Ambient air pollution is a leading cause of premature death around the world. Globally, more than 4.2 million annual fatalities – in the form of cardiovascular disease, ischemic heart disease, stroke and lung cancer – were attributed to air pollution in 2015, according to a Lancet study cited in the Cornell research.

In this work, the group developed four machine learning models for traffic-related particulate matter concentrations in data gathered in New York City’s five boroughs, which have a combined population of 8.2 million people and a daily-vehicle miles traveled of 55 million miles.

The equations use few inputs such as traffic data, topology and meteorology in an AI algorithm to learn simulations for a wide range of traffic-related, air-pollution concentration scenarios.

Their best performing model was the Convolutional Long Short-term Memory, or ConvLSTM, which trained the algorithm to predict many spatially correlated observations.

“Our data-driven approach – mainly based on vehicle emission data – requires considerably fewer modeling steps,” Desai said. Instead of focusing on stationary locations, the method provides a high-resolution estimation of the city street pollution surface. Higher resolution can help transportation and epidemiology studies assess health, environmental justice and air quality impacts.

Funding for this research came from the U.S. Department of Transportation’s University Transportation Centers Program and Cornell Atkinson.

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January 13, 2023
Toward standardized tests for assessing lidars in autonomous vehicles

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Newswise — Today, autonomous vehicles (AVs) and advanced driver assistance systems (ADASs) are rapidly growing research directions aimed at increasing vehicle and road safety. Both technologies minimize human error by enabling cars to “perceive” their surroundings and act accordingly. This is achieved using light detection and ranging (lidar) technology, one of the most important and versatile components in AVs. Lidars provide a three-dimensional map of all objects around the vehicle regardless of external lighting conditions. This map, updated hundreds of times per second, can be used to estimate the position of the vehicle relative to its surroundings in real time

Despite their crucial role in both AVs and ADAS, however, lidars currently lack a standardized measure for describing their performance. In other words, there is no widely accepted protocol for comparing one lidar with another. Although one could arguably compare lidars based solely on their manufacturers’ specifications, such comparisons are not very useful. This is because the performance metrics used by the manufacturers vary and are typically confidential. Moreover, unlike lidars used for science, surveyance, or defense applications, automotive-grade lidars are optimized for manufacturability, cost, and size. This is likely to lead to marked variations in performance that would be impossible to quantify without standardized tests.

To tackle this problem, Dr. Paul McManamon of Exciting Technology formed a national group in conjunction with SPIE to address the issue with a three-year effort to develop tests and performance standards for lidars used in AVs and ADAS. The tests during the first year were led by Dr. Jeremy P. Bos, an associate professor at Michigan Technological University (MTU), with assistance from his PhD student, Zach Jeffries. Other authors included Charles Kershner from the National Geospatial-Intelligence Agency, who set up a ground truth Reigl lidar for the test, and Akhil Kurup, also of MTU. In a paper published recently in Optical Engineering, the team reports the findings of the first-year tests and a briefing outline of the larger three-year plan.

The objective of these tests was to evaluate the range, accuracy, and precision of eight automotive-grade lidars using a survey-grade lidar as a reference. Bos, Jeffries, and the team set up various targets along a 200-meter path in an open field in Kissimmee, Florida. One key aspect of these targets that made the tests stand out from previous studies was that they were near-perfect matte surfaces with a calibrated 10% reflectivity across a wide spectrum. The researchers also measured the ability of the lidars to detect the target among highly reflective road signs.

The tests results were, in general, consistent with the values advertised in the manufacturer’s datasheets. However, despite recording a mean precision of 2.9 cm across all the tested devices, the distribution of the measured values was not Gaussian. Simply put, there was a non-negligible probability for these devices to report very imprecise values (error greater than 10 cm). In fact, in some cases, the measured range deviated from the real value by as much as 20 cm. Another important result was that the reflective road signs impaired the target detection performance of the lidars. “The advertised range performance of lidars pertains to very specific conditions, and performance degrades significantly in the presence of a highly reflective adjacent object,” said Bos.

Overall, the first round of tests provided important insights into the performance differences between different lidars, suggesting that the metrics reported by their respective manufacturers are not reliable. Still, Bos emphasizes this is only the beginning. “The first-year tests were the simplest of them. In the second year, we will duplicate these tests for the characterized lidars while introducing confusion resulting from other automotive lidars approaching from the opposite direction. Additionally, we will measure the eye safety of the lidars,” said Bos. “Finally, in the third year, we will include weather effects as a culmination of the complexity build-up.”

The team’s efforts will help decisionmakers, engineers, and manufacturers realize the importance of lidar standardization and ultimately make our roads safer.

Read the open access paper by Jeffries et al., “Towards open benchmark tests for automotive lidars, year 1: static range error, accuracy, and precision” Opt. Eng. 62(3) 031211 (2023). doi: 10.1117/1.OE.62.3.031211.

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January 6, 2023
London Underground polluted with metallic particles small enough to enter human bloodstream

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Newswise — The London Underground is polluted with ultrafine metallic particles small enough to end up in the human bloodstream, according to University of Cambridge researchers. These particles are so small that they are likely being underestimated in surveys of pollution in the world’s oldest metro system.

The researchers carried out a new type of pollution analysis, using magnetism to study dust samples from Underground ticket halls, platforms and operator cabins.

The team found that the samples contained high levels of a type of iron oxide called maghemite. Since it takes time for iron to oxidise into maghemite, the results suggest that pollution particles are suspended for long periods, due to poor ventilation throughout the Underground, particularly on station platforms.

Some of the particles are as small as five nanometres in diameter: small enough to be inhaled and end up in the bloodstream, but too small to be captured by typical methods of pollution monitoring. However, it is not clear whether these particles pose a health risk.

Other studies have looked at overall pollution levels on the Underground and the associated health risks, but this is the first time that the size and type of particles has been analysed in detail. The researchers suggest that periodic removal of dust from Underground tunnels, as well as magnetic monitoring of pollution levels, could improve air quality throughout the network. Their results are reported in the journal Scientific Reports.

The London Underground carries five million passengers per day. Multiple studies have shown that air pollution levels on the Underground are higher than those in London more broadly, and beyond the World Health Organization’s (WHO) defined limits. Earlier studies have also suggested that most of the particulate matter on the Underground is generated as the wheels, tracks and brakes grind against one another, throwing up tiny, iron-rich particles.

“Since most of these air pollution particles are metallic, the Underground is an ideal place to test whether magnetism can be an effective way to monitor pollution,” said Professor Richard Harrison from Cambridge’s Department of Earth Sciences, the paper’s senior author. “Normally, we study magnetism as it relates to planets, but we decided to explore how those techniques could be applied to different areas, including air pollution.”

Pollution levels are normally monitored using standard air filters, but these cannot capture ultrafine particles, and they do not detect what kinds of particles are contained within the particulate matter.

“I started studying environmental magnetism as part of my PhD, looking at whether low-cost monitoring techniques could be used to characterise pollution levels and sources,” said lead author Hassan Sheikh from Cambridge’s Department of Earth Sciences. “The Underground is a well-defined micro-environment, so it’s an ideal place to do this type of study.”

Working with colleagues from Cambridge’s Department of Materials Science and Metallurgy, Sheikh and Harrison analysed 39 dust samples from the London Underground, provided by Transport for London (TfL). The samples were collected in 2019 and 2021 from platforms, ticket halls, and train operator cabins on the Piccadilly, Northern, Central, Bakerloo, Victoria, Northern, District and Jubilee lines. The sampling included major stations such as King’s Cross St Pancras, Paddington, and Oxford Circus.

The researchers used magnetic fingerprinting, 3D imaging and nanoscale microscopy to characterise the structure, size, shape, composition and magnetic properties of particles contained in the samples. Earlier studies have shown that 50% of the pollution particles in the Underground are iron-rich, but the Cambridge team were able to look in much closer detail. They found a high abundance of maghemite particles, ranging in diameter from five to 500 nanometres, and with an average diameter of 10 nanometres. Some particles formed larger clusters with diameters between 100 and 2,000 nanometres.

“The abundance of these very fine particles was surprising,” said Sheikh. “The magnetic properties of iron oxides fundamentally change as the particle size changes. In addition, the size range where those changes happen is the same as where air pollution becomes a health risk.”

While the researchers did not look at whether these maghemite particles pose a direct health risk, they say that their characterisation methods could be useful in future studies.

“If you’re going to answer the question of whether these particles are bad for your health, you first need to know what the particles are made of and what their properties are,” said Sheikh.

“Our techniques give a much more refined picture of pollution in the Underground,” said Harrison. “We can measure particles that are small enough to be inhaled and enter the bloodstream. Typical pollution monitoring doesn’t give you a good picture of the very small stuff.”

The researchers say that due to poor ventilation in the Underground, iron-rich dust can be resuspended in the air when trains arrive at platforms, making the air quality on platforms worse than in ticket halls or in operator cabins.

Given the magnetic nature of the resuspended dust, the researchers suggest that an efficient removal system might be magnetic filters in ventilation, cleaning of the tracks and tunnel walls, or placing screen doors between platforms and trains.

The research was supported in part by the European Union, the Cambridge Trust and Selwyn College, Cambridge.

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December 15, 2022
Tackling Crowd Management in Subways during Pandemics

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Newswise — Mass transit, and subways in particular, are essential to the economic viability and environmental sustainability of cities across the globe. But public transit was hit hard during the COVID pandemic and subways especially experienced substantial drops in ridership. Spurred on by a Columbia Engineering Transit Design Challenge in 2020, researchers from across the University have been collaborating on a project to strengthen both the preparedness and resilience of transit communities facing public health disasters.

The team, led by Civil Engineering Professor Sharon Di, recently won a $2,500,000 four-year grant from the National Science Foundation to tackle crowd management in subways. The project–”Preparing for Future Pandemics: Subway Crowd Management to Minimize Airborne Transmission of Respiratory Viruses”–is focused on developing a system for public transit communities, including riders, workers, and agencies, that will help transit riders to make informed decisions and adapt travel behavior accordingly and provide transit agencies engaged in planning and policymaking with recommendations for mitigating virus transmission risks to riders and workers.

“We think our system, which we’re calling Way-CARE, will be transformative, especially for people in low-income communities who are among the most impacted by reduced accessibility to safer travel modes,” said Di, who is a leader in transportation management. “We expect our project to improve the social, economic, and environmental well-being of those who live, work, and travel within cities.”

The team, which includes Co-PIs Jeffrey Shaman (Columbia Climate School; Mailman School of Public Health); Marco Giometto, Xiaofan Jiang, and Faye McNeill (Columbia Engineering); Ester Fuchs (School of International and Public Affairs); and Kai Ruggeri (Columbia University Irving Medical Center), is working with New York City’s Metropolitan Transportation Authority and local rider communities in Harlem and at Columbia on the Way-CARE project. They hope that their system will enable smart city transit operators to access real-time sensing information collected from subway stations and/or trains for crowd management.

The researchers are integrating sensing and crowd and airflow modeling with public health expertise on a microscale applied to subway crowd management. They are developing coupled airborne dispersion and epidemiological models that account for microscale processes–the transport of droplets and aerosols–that affect respiratory virus transmission. In addition, they are integrating behavioral science data that will help inform travel choices and policy making.

“This is an important interdisciplinary collaboration,” said Shaman, an epidemiologist who is a leader in infectious disease modeling. “The transmission of respiratory viruses is not directly observed, and the microscale processes influencing infection risk are not well known. Our project will address these shortcomings by advancing understanding of the physical, biological, and behavioral features that enable transmission of respiratory viruses in subway settings, and equip transit officials and the public with real-time information that improves worker and rider safety.”

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December 15, 2022
Inexpensive Airborne Testbeds Could Study Hypersonic Technologies

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Newswise — Miniature satellites known as CubeSats are taking on larger roles in space missions that might previously have been carried out by more expensive conventional spacecraft. Now, researchers at the Georgia Institute of Technology are envisioning a still larger mission for CubeSats as airborne testbeds for technologies that are being developed for future generations of hypersonic vehicles.

Development of hypersonic vehicles able to travel through the Earth’s atmosphere at Mach 5 or faster – five times the speed of sound – is attracting substantial new government and industry funding. But test facilities needed to evaluate thermodynamic, aerodynamic, acoustic, and other issues critical to operating in that harsh environment are limited, in high demand, and costly to use.

Georgia Tech researchers want to eliminate that roadblock by building hardened CubeSats that could use re-entry from space to generate the conditions needed to evaluate hypersonic technologies. The small satellites, with their key systems protected from the heat of re-entry, would be launched into the upper atmosphere from the International Space Station or a “rideshare” rocket to provide several minutes of testing at velocities of up to Mach 25.

“We are looking at the feasibility of building what would be an inexpensive flying wind tunnel,” said Krish Ahuja, Regents Professor of Aerospace Engineering and division chief for aerospace and acoustics in the Aerospace, Transportation, and Advanced Systems Laboratory of the Georgia Tech Research Institute (GTRI) and the project’s principal investigator. “We could gather pretty much any data that would be needed for hypersonic research and provide a new way to conduct studies that now can be quite difficult to do.”

Initial Study Suggests Developing 6U Vehicle

Based on a six-month feasibility study that included collaborators from Georgia Tech’s School of Aerospace Engineering and two private companies, Ahuja believes it would be worthwhile to pursue design of a 6U test vehicle to evaluate the concept. (A 6U CubeSat is about the size of the system unit of a desktop computer). If that proves promising, larger vehicles could be constructed with more capable instrumentation, guidance, and even propulsion.

The goal of the project’s first year is to understand what would be required to develop and launch the flying testbeds – and recover them after flight. Design and development of the new test vehicles must overcome significant challenges related to controlling the flight duration, speed, altitude, and orientation of the vehicle during data collection. Systems to communicate with the ground and track the vehicle’s trajectory must also be developed. Also, part of the first-year goal is creation of a roadmap showing the development and test process.

“Ongoing work will include a ‘system-of-systems’ analysis of the concept to model its performance and interaction with other support systems to assess its capability to conduct scientific research,” Ahuja said. “Our initial calculations indicate that a 6U CubeSat could be hardened with a thermal protection system for hypersonic conditions to help conduct limited feasibility experiments. This will be a building block for future systems that would be larger and able to conduct the testing we envision.”

Initial testing is likely to involve free fall of the test vehicle, but subsequent tests would include control surfaces that would provide steering to prevent tumbling and other undesired effects. Multiple CubeSats could also be operated together.

Possible New Capabilities for Small Satellites

CubeSats, so-called because they are designed in standard cube sizes, aren’t normally designed to be recovered after a mission; when their work is done, they simply burn up in the atmosphere. Because Ahuja wants to study effects on materials and capture data from on-board instruments, the flying wind tunnel satellites will need to be recovered using parachutes that would drop them into a recovery zone, perhaps in the desert Southwest.

“Getting them down at the right location will require good guidance and control, good telemetry, and a propulsion system,” he said. “The challenge will be to make these very small and inexpensive. To get the information we need, we will have to bring the testbed safely to the ground.”

The high temperatures generated by re-entry into the Earth’s atmosphere could be useful for more than simulating hypersonic conditions. Ahuja believes the heat could be used to operate a proprietary device that could provide steering for the CubeSats, which normally don’t have propulsion systems.

Much of current research on hypersonic flight depends on data from computational fluid dynamics simulations, which need validation from testing. Beyond the information gained from the testbed, Ahuja believes the small spacecraft could make big contributions by providing a real-world anchor for the analysis tools that researchers are using for a variety of hypersonic vehicles.

A New Approach to Hypersonic Testing is Needed

Hypersonic testing is typically done in short-duration wind tunnels or high-temperature testbeds, meaning high-speed and high-temperature conditions are difficult to achieve simultaneously and at test durations relevant to hypersonic vehicles. In addition, there are few existing facilities where such testing can be done, and they are in high demand. The new testbed is expected to provide about three minutes of testing per flight.

Currently, there is a critical need to understand how much and what kind of thermal protection system is needed to protect hypersonic vehicles at high velocities where friction can produce temperatures of more than 4,000 degrees F. Additionally, there are questions about acoustic effects and how uneven heating will spread across a vehicle and potentially damage its structure.

“The airflow across a hypersonic vehicle can be both turbulent and laminar, different on different parts of the vehicle,” said Ahuja. “These wide variations of the flow properties can produce large variation in temperatures over the vehicle surface, which is highly undesirable with respect to vehicle’s structural integrity. As such, we need to understand what is happening to the material as a result of temperature changes over time. This thermal loading cannot be studied in conventional wind tunnels, which normally offer fractions of seconds of run time at hypersonic conditions, because it takes a while for those conditions to become steady.”

Acoustic loading can also dramatically affect the structural integrity of a hypersonic vehicle, and that likewise requires time to evaluate. “Acoustic loading of the kind that could generate a crack in a structure that develops over time,” he said. “We could create and study these conditions with our flying testbed.”

Funding from GTRI’s Independent Research and Development (IRAD) program has supported the initiative so far, and by gathering enough data from the initial studies, Ahuja hopes to attract collaborators to help implement the new test approach.

“There is so much enthusiasm for this that I believe our chances of success are high,” he said. “By launching from another space system, we won’t have to worry about the initial launch propulsion. This could address a lot of challenges in conducting hypersonic research.”

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December 4, 2022
Argonne and Oak Ridge national laboratories collaborate with Wabtec on hydrogen-powered trains to decarbonize rail industry

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Newswise — Hydrogen-powered trains on track to decarbonize the rail industry.

As the United States shifts away from fossil fuel burning cars and trucks, scientists at the U.S. Department of Energy’s (DOE) Argonne National Laboratory and Oak Ridge National Laboratory (ORNL) are exploring options for another form of transportation: trains. The research focuses on zero carbon hydrogen and other low-carbon fuels as viable alternatives to diesel for the rail industry.

Both laboratories have entered into cooperative research and development agreements with Wabtec, a leading manufacturer of freight locomotives. The Argonne and Wabtec agreement also includes Convergent Science, a software developer. The project will run for four years.

Researchers from the multidisciplinary team kicked off the project and celebrated the installation of rail technology company Wabtec’s single cylinder dual-fuel locomotive engine in the National Transportation Research Center, a DOE-designated user facility located at ORNL, during a Nov. 9 event.

“While hydrogen has been used in light-duty combustion engines, it is still a very new area of research in railway applications.” — Muhsin Ameen, Argonne senior research scientist

Hydrogen as fuel has many advantages, but locomotive engines must be modified to ensure safe, efficient and clean operation. The team will develop hardware and control strategies for the engine, which will run on hydrogen and diesel fuel to demonstrate the viability of using alternative fuels.

“We are excited to be a part of this collaboration because it addresses the need to decarbonize the rail industry by advancing hydrogen engine technology for both current and future locomotives,” said Josh Pihl, an ORNL distinguished researcher and group leader for applied catalysis and emissions research. “It is also a perfect example of how a DOE-funded collaboration between industry and national laboratories can accelerate the development and commercialization of technologies to help reduce carbon emissions from transportation.”

Pihl said the project aligns with the goals of DOE’s Vehicle Technologies Office to use low-carbon fuels in hard-to-electrify transportation sectors. While electrifying vehicles is an effective strategy in reducing carbon emissions from some parts of the transportation sector, railways are considered more difficult because of the high cost of building a single coordinated electrified rail system across North America. Each year, the North American rail fleet emits approximately 87.6 billion pounds of carbon dioxide, a major driver of climate change.

Researchers are exploring the potential of hydrogen combustion engine technology in the rail industry, said Muhsin Ameen, Argonne senior research scientist. Hydrogen is an energy carrier that can be produced from clean energy sources such as solar and wind power. Scientists have studied hydrogen-powered vehicles for decades.

“To reduce carbon dioxide emissions to net zero by 2050, we must make dramatic improvements in energy efficiency and emissions in the overall transportation system, including railways,” said Ameen. “Hydrogen has been used in light-duty combustion engines. However, hydrogen is a newer area of research in railway applications.”

The research team is developing combustion technology to power the next generation of trains with up to 100% hydrogen and other low-carbon fuels. The team’s goal is to design train engines that will deliver the same power, range and cost-effectiveness as current diesel technology.

“This collaboration with Argonne and Oak Ridge national laboratories with DOE support will advance the development of hydrogen technology within Wabtec’s existing industry-leading platforms for medium-speed engines. Railroads will be able to greatly reduce emissions and operating costs while maintaining commonality within their current fleet of trains,” said James Gamble, vice president of Engine & Power Solutions Technology at Wabtec.

In the project’s first phase, the ORNL team will work on hardware changes for retrofitting locomotives. Their goal is to reduce CO₂ emissions from the roughly 25,000 locomotives already in use in North America. Locomotives have a service life of more than 30 years, so replacing the entire fleet would take decades.

During the second phase of the project, Argonne will leverage more than a decade of experience in modeling hydrogen injection and combustion to create a modeling framework to study combustion and emission control technologies used in hydrogen combustion engines. Experts in fuel injection, kinetics and combustion modeling, design optimization, high performance computing and machine learning will take the project from start to finish.

At the same time, ORNL and Wabtec will continue to alter the engine hardware to increase the amount of hydrogen that can be used. The team aims to completely replace diesel with hydrogen or low-carbon fuels in new locomotives.

Scientists are using Argonne’s high performance computers to develop simulation software. This tool will help predict the behavior of combustion engines as operating conditions change and hardware is modified. Simulations help researchers understand the combustion process, which drives engine efficiency and reduces emissions.

Each diesel-powered locomotive that is converted to a zero- or low-carbon energy source is anticipated to save up to 5.6 million pounds of carbon dioxide per year.

Along with Ameen, the Argonne team includes group leader and principal research scientist Riccardo Scarcelli, postdoctoral fellow Samuel Kamouz and principal engine research scientist Christopher Powell.

In addition to Pihl, the ORNL team includes research engineers Dean Edwards and Eric Nafziger and research mechanic Steve Whitted.

The project is funded by the Vehicle Technologies Office under DOE’s Office of Energy Efficiency and Renewable Energy and Wabtec. In-kind contributions are provided by Wabtec and Convergent Science. The U.S. Department of Transportation Federal Railroad Administration is also funding related research on safe use of hydrogen in locomotive engines.

Wabtec Corporation (NYSE: WAB) is focused on creating transportation solutions that move and improve the world. The company is a leading global provider of equipment, systems, digital solutions and value-added services for the freight and transit rail industries, as well as the mining, marine and industrial markets. Wabtec has been a leader in the rail industry for over 150 years and has a vision to achieve a zero-emission rail system in the U.S. and worldwide. Visit Wabtec’s website at: www.wabteccorp.com.

UT-Battelle manages ORNL for the Department of Energy’s Office of Science, the single largest supporter of basic research in the physical sciences in the United States. The Office of Science is working to address some of the most pressing challenges of our time. For more information, please visit energy.gov/science.

Argonne National Laboratory seeks solutions to pressing national problems in science and technology. The nation’s first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their specific problems, advance America’s scientific leadership and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science.

The U.S. Department of Energy’s Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, visit https://energy.gov/science.

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November 14, 2022
Top 10 Most Visited Cruise Ports According to the Users of the Visited Travel App

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Find out which Cruise ports made the Top 10 Most Visited List. Users can also see what percentage of all the ports/cities they have seen with the travel app, Visited.

Press Release
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Jul 7, 2022

TORONTO, July 7, 2022 (Newswire.com)
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Get inspired by the Visited App’s Top 10 Most Visited Cruise Ports published by Arriving In High Heels, the company behind Visited. Visited is a travel app, that started off with a simple idea of mapping out where travelers have been to and where they want to go in the future. It later expended to provide users with personal travel stats on how many countries they have seen, how many cities they have visited and what percentage of the world that they want to see they covered. Today, the app also allows users to check off destinations, countries, cities and experiences that they have been to. The travel app also helps discover new destinations by allowing users to swipe between different travel sights that they can then add to their bucket-list.

Our global trotting users have selected the following cruise ports the greatest number of times:

1. Barcelona, Spain

2. Venice, Italy

3. Amsterdam, Netherlands

4. Miami, United States

5. New York, United States

6. Lisbon, Portugal

7. Cozumel, Mexico

8. Copenhagen, Denmark

9. Stockholm, Sweden

10. Helsinki, Finland

To see the full list of ports and what percentage you have visited, download Visited for free on iOS or Android .

To learn more about the Visited app, get more travel insights and its latest feature update, please visit https://visitedapp.com/.

About Arriving In High Heels Corporation

Arriving In High Heels Corporation is a mobile app company; Visited is their most popular app. For inspiration on travel destinations, travel stats and the latest travel news, follow Visited on Facebook, Twitter, Instagram, and Pinterest. Other apps include Pay Off Debt and X-Walk.

Contact Information

Anna Kayfitz

anna@arrivinginhighheels.com

Source: Arriving In High Heels Corporation

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July 7, 2022