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1. Hydrogen Station Location Planning via Geodesign in Connecticut: Comparing Optimization Models and Structured Stakeholder Collaboration

   https://doi.org/10.3390/en14227747  

   Lopez Jaramillo, Oscar; Rinebold, Joel; Kuby, Michael; Kelley, Scott; Ruddell, Darren; Stotts, Rhian; Krafft, Aimee; Wentz, Elizabeth (November 2021, Energies)

   Geodesign is a participatory planning approach in which stakeholders use geographic information systems to develop and vet alternative design scenarios in a collaborative and iterative process. This study is based on a 2019 geodesign workshop in which 17 participants from industry, government, university, and non-profit sectors worked together to design an initial network of hydrogen refueling stations in the Hartford, Connecticut, metropolitan area. The workshop involved identifying relevant location factors, rapid prototyping of station network designs, and developing consensus on a final design. The geodesign platform, which was designed specifically for facility location problems, enables breakout groups to add or delete stations with a simple point-and-click operation, view and overlay different map layers, compute performance metrics, and compare their designs to those of other groups. By using these sources of information and their own expert local knowledge, participants recommended six locations for hydrogen refueling stations over two distinct phases of station installation. We quantitatively and qualitatively compared workshop recommendations to solutions of three optimal station location models that have been used to recommend station locations, which minimize travel times from stations to population and traffic or maximize trips that can be refueled on origin–destination routes. In a post-workshop survey, participants rated the workshop highly for facilitating mutual understanding and information sharing among stakeholders. To our knowledge, this workshop represents the first application of geodesign for hydrogen refueling station infrastructure planning. 

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2. Hydrogen Refueling Station Consideration and Driver Experience in California

   https://doi.org/10.1177/0361198120956999  

   Krafft, Aimee; Kelley, Scott; Kuby, Michael; Lopez Jaramillo, Oscar G.; Stotts, Rhian (January 2021, Transportation Research Record: Journal of the Transportation Research Board)

   null (Ed.)

   The recent growth in the California hydrogen fuel cell vehicle (FCV) market offers the opportunity to analyze how refueling stations that drivers use after some experience compare with those they initially intended to use. Online surveys completed by 124 FCV adopters in California in early 2019 were analyzed. Respondents listed stations they initially planned to use, stations that they later used, subjective reasons for using them, and important travel destinations. Network GIS analysis was then used to measure estimated travel times between both available and planned retail hydrogen stations and home, work, and frequently traveled routes, both at the time of adoption and at the time of the survey. Results show that 40% of respondents changed refueling stations over time. Those with stations objectively nearer to home, work, and frequently traveled routes were less likely to change their list. Drivers were more likely to subjectively label stations as near home and less likely to label them as on the way compared with objective measurements of these criteria, though these differences are greater for respondents who changed stations. Regardless of whether the station was available pre-adoption or opened post-adoption, stations that respondents added to their lists were farther from home than those they initially intended to use. For stations available pre-adoption, reliability positively influenced adding them after experience, while stations added by drivers that opened post-adoption tended to require short deviations to reach. These results indicate that a mixture of geographic and station-level characteristics contribute to FCV drivers changing stations over time. 

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3. Experimental Comparison of Hydrogen Refueling with Directly Pressurized vs. Cascade Method

   https://doi.org/10.3390/en16155749  

   Genovese, Matteo; Blekhman, David; Dray, Michael; Piraino, Francesco; Fragiacomo, Petronilla (August 2023, Energies)

   This paper presents a comparative analysis of two hydrogen station configurations during the refueling process: the conventional “directly pressurized refueling process” and the innovative “cascade refueling process.” The objective of the cascade process is to refuel vehicles without the need for booster compressors. The experiments were conducted at the Hydrogen Research and Fueling Facility located at California State University, Los Angeles. In the cascade refueling process, the facility buffer tanks were utilized as high-pressure storage, enabling the refueling operation. Three different scenarios were tested: one involving the cascade refueling process and two involving compressor-driven refueling processes. On average, each refueling event delivered 1.6 kg of hydrogen. Although the cascade refueling process using the high-pressure buffer tanks did not achieve the pressure target, it resulted in a notable improvement in the nozzle outlet temperature trend, reducing it by approximately 8 °C. Moreover, the overall hydrogen chiller load for the two directly pressurized refuelings was 66 Wh/kg and 62 Wh/kg, respectively, whereas the cascading process only required 55 Wh/kg. This represents a 20% and 12% reduction in energy consumption compared to the scenarios involving booster compressors during fueling. The observed refueling range of 150–350 bar showed that the cascade process consistently required 12–20% less energy for hydrogen chilling. Additionally, the nozzle outlet temperature demonstrated an approximate 8 °C improvement within this pressure range. These findings indicate that further improvements can be expected in the high-pressure region, specifically above 350 bar. This research suggests the potential for significant improvements in the high-pressure range, emphasizing the viability of the cascade refueling process as a promising alternative to the direct compression approach. 

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4. Rapid molecular evolution of pain insensitivity in multiple African rodents

   https://doi.org/10.1126/science.aau0236  

   Eigenbrod, Ole; Debus, Karlien Y.; Reznick, Jane; Bennett, Nigel C.; Sánchez-Carranza, Oscar; Omerbašić, Damir; Hart, Daniel W.; Barker, Alison J.; Zhong, Wei; Lutermann, Heike; et al (May 2019, Science)

   Noxious substances, called algogens, cause pain and are used as defensive weapons by plants and stinging insects. We identified four previously unknown instances of algogen-insensitivity by screening eight African rodent species related to the naked mole-rat with the painful substances capsaicin, acid (hydrogen chloride, pH 3.5), and allyl isothiocyanate (AITC). Using RNA sequencing, we traced the emergence of sequence variants in transduction channels, like transient receptor potential channel TRPA1 and voltage-gated sodium channel Na v 1.7, that accompany algogen insensitivity. In addition, the AITC-insensitive highveld mole-rat exhibited overexpression of the leak channel NALCN (sodium leak channel, nonselective), ablating AITC detection by nociceptors. These molecular changes likely rendered highveld mole-rats immune to the stings of the Natal droptail ant. Our study reveals how evolution can be used as a discovery tool to find molecular mechanisms that shut down pain. 

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5. A Comprehensive Survey on Basic Safety Message Attacks and Their Detection

   https://doi.org/10.1007/978-3-031-89360-5_7  

   Mohamed, Ahmed; Xie, Mengjun (May 2025, Springer Nature Switzerland)

   Vehicular Ad-hoc Networks (VANETs) are a crucial component of Cooperative Intelligent Transportation Systems (C-ITS), enabling vehicles to communicate and share vital information to enhance road safety and efficiency. Basic Safety Messages (BSMs), periodically broadcast by vehicles to provide real-time kinematic data, form the foundation of numerous safety applications within VANETs. Ensuring the security of BSMs is paramount, as malicious entities can exploit vulnerabilities to launch attacks that could have catastrophic consequences. In this study, we provide a comprehensive analysis of BSM attacks and detection mechanisms in VANETs. We begin by outlining the system model, security requirements, and attacker models relevant to BSMs. Then, we categorize and describe a range of attacks, from simple position falsification to more sophisticated and evasive techniques, such as the SixPack attack. We also classify existing attack detection methods into machine learning-based, deep learning-based, plausibility and consistency-based, and software-defined networking (SDN)-based mechanisms, analyzing their effectiveness and limitations. Additionally, we highlight the challenges in securing BSMs, such as the trade-off between model accuracy and real-time performance. Future research directions are also discussed. This survey paper serves as a foundational step towards building safe, secure, and reliable cooperative intelligent transportation systems and their associated applications. 

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