Browsing by Author "Buehler, Ralph"

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    The 2019 Conference on Health and Active Transportation: Research Needs and Opportunities
    Berrigan, David; Dannenberg, Andrew L.; Lee, Michelle; Rodgers, Kelly; Wojcik, Janet R.; Wali, Behram; Tribby, Calvin P.; Buehler, Ralph; Sallis, James F.; Roberts, Jennifer D.; Steedly, Ann; Peng, Binbin; Eisenberg, Yochai; Rodriguez, Daniel A. (MDPI, 2021-11-11)
    Active transportation (AT) is widely viewed as an important target for increasing participation in aerobic physical activity and improving health, while simultaneously addressing pollution and climate change through reductions in motor vehicular emissions. In recent years, progress in increasing AT has stalled in some countries and, furthermore, the coronavirus (COVID-19) pandemic has created new AT opportunities while also exposing the barriers and health inequities related to AT for some populations. This paper describes the results of the December 2019 Conference on Health and Active Transportation (CHAT) which brought together leaders from the transportation and health disciplines. Attendees charted a course for the future around three themes: Reflecting on Innovative Practices, Building Strategic Institutional Relationships, and Identifying Research Needs and Opportunities. This paper focuses on conclusions of the Research Needs and Opportunities theme. We present a conceptual model derived from the conference sessions that considers how economic and systems analysis, evaluation of emerging technologies and policies, efforts to address inclusivity, disparities and equity along with renewed attention to messaging and communication could contribute to overcoming barriers to development and use of AT infrastructure. Specific research gaps concerning these themes are presented. We further discuss the relevance of these themes considering the pandemic. Renewed efforts at research, dissemination and implementation are needed to achieve the potential health and environmental benefits of AT and to preserve positive changes associated with the pandemic while mitigating negative ones.
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    Assessment of the Jones Act Waiver Process on Freight Transportation Networks Experiencing Disruption
    Fialkoff, Marc Richard (Virginia Tech, 2017-10-27)
    In October 2012, Hurricane Sandy caused massive disruption and destruction to the Mid-Atlantic region of the United States. The intensity of the storm forced the Port of New York and New Jersey to close, forcing cargo diversion to the Port of Norfolk in Virginia. Because of the Jones Act restriction on foreign vessels moving between U.S. ports, the restriction on short sea shipping was viewed as a barrier to recovery. Much of the critical infrastructure resilience and security literature focuses on the "hardening" of physical infrastructure, but not the relationship between law, policy, and critical infrastructure. Traditional views of transportation systems do not adequately address questions of governance and behaviors that contribute to resilience. In contrast, recent development of a System of Systems framework provides a conceptual framework to study the relationship of law and policy systems to the transportation systems they govern. Applying a System of Systems framework, this research analyzed the effect of relaxing the Jones Act on freight transportation networks experiencing a disruptive event. Using WebTRAGIS (Transportation Routing Analysis GIS), the results of the research demonstrate that relaxing the Jones Act had a marginal reduction on highway truck traffic and no change in rail traffic volume in the aftermath of a disruption. The research also analyzed the Jones Act waiver process and the barriers posed by the legal process involved in administration and review for Jones Act waivers. Recommendations on improving the waiver process include greater agency coordination and formal rulemaking to ensure certainty with the waiver process. This research is the first in studying the impact of the Jones Act on a multimodal freight transportation network. Likewise, the use of the System of Systems framework to conceptualize the law and a critical infrastructure system such as transportation provides future opportunities for studying different sets of laws and policies on infrastructure. This research externalizes law and policy systems from the transportation systems they govern. This can provide policymakers and planners with an opportunity to understand the impact of law and policy on the infrastructure systems they govern.
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    Built Environment Determinants of Pedestrian Activities and Their Consideration in Urban Street Design
    Gerike, Regine; Koszowski, Caroline; Schröter, Bettina; Buehler, Ralph; Schepers, Paul; Weber, Johannes; Wittwer, Rico; Jones, Peter (MDPI, 2021-08-20)
    Pedestrian facilities have been regarded in urban street design as “leftover spaces” for years, but, currently, there is a growing interest in walking and improving the quality of street environments. Designing pedestrian facilities presents the challenge of simultaneously accommodating (1) pedestrians who want to move safely and comfortably from point A to B (movement function); as well as (2) users who wish to rest, communicate, shop, eat, and enjoy life in a pleasant environment (place function). The aims of this study are to provide an overview of how the task of designing pedestrian facilities is addressed in international guidance material for urban street design, to compare this with scientific evidence on determinants of pedestrian activities, and to finally develop recommendations for advancing provisions for pedestrians. The results show that urban street design guidance is well advanced in measuring space requirements for known volumes of moving pedestrians, but less in planning pleasant street environments that encourage pedestrian movement and place activities. A stronger linkage to scientific evidence could improve guidance materials and better support urban street designers in their ambition to provide safe, comfortable and attractive street spaces that invite people to walk and to stay.
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    Changes in Travel Behavior, Attitudes, and Preferences among E-Scooter Riders and Non-Riders: A First Look at Results from Pre and Post E-Scooter System Launch Surveys at Virginia Tech
    Buehler, Ralph; Broaddus, Andrea; Swenney, Ted; Mollenhauer, Michael A.; White, Elizabeth; Zhang, Wenwen (2021-04-22)
    Shared micromobility such as electric scooters (e-scooters) has potential to enhance the sustainability of urban transport by displacing car trips, providing more mobility options, and improving access to public transit. Most published studies on e-scooter ridership focus on cities and only capture data at one point in time. This study reports results from two cross-sectional surveys deployed before (n=462) and after (n=428) the launch of a fleet of shared e-scooters on Virginia Tech’s campus in Blacksburg, VA. This allowed for a pre-post comparison of attitudes and preferences of e-scooter riders and non-users. E-scooter ridership on campus follows patterns identified in other studies, with a greater share of younger riders—in particular undergraduate students. Stated intention to ride prior to system launch was greater than actual ridership after system launch. The drop-off between pre-launch intention to ride and actual riding was strongest for older age groups, women, and university staff. As in city surveys, the main reasons for riding e-scooters on campus were travel speed and fun of riding. About 30% indicated using e-scooters to ride to parking lots or to access public transport service—indicating e-scooters’ potential as connector to other modes of transport. Compared to responses prior to system launch, perceptions about the convenience, cost, safety, parking, rider behavior, and usefulness of the e-scooter systems were more positive among non-riders after system launch—indicating that pilot projects may improve public perception of e-scooters. Building more bike lanes or separate spaces for e-scooters to ride could help move e-scooter riders off sidewalks—a desire expressed by both pedestrians and e-scooter users.
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    Climate Change Vulnerabilities in Loíza: The Role of Transportation in Enhancing Resilience
    Gonzalez-Velez, Justine Ivan (Virginia Tech, 2024-06-24)
    Climate change-related vulnerabilities in Loíza are prevalent in both physical and social dimensions. The social-ecological systems indicate that a change in one component will trigger an effect in the other regardless if physical or not, suggesting that the examination of vulnerabilities cannot be done overlooking one dimension. Such is the case of transportation, as climate change vulnerabilities in Puerto Rico are exacerbated due to the capacity of the Island to recover from a disaster, mainly because there are nearly no options for mobility aside from a private vehicle. This research intended to describe the social vulnerabilities of the population and asses the physical vulnerabilities of the transportation infrastructure of Loíza to understand how resilience is threatened using the social-ecological systems approach. This study found that the transportation infrastructure is exposed and sensitive to sea level rise, flooding, and strong winds, mainly because these climate stressors cause damage to the roadways and inhibit the flow and traffic of people throughout the main roadway and evacuation route, the PR-187. The study also identified that Loíza is socially vulnerable. Many people belong to one of the described vulnerable groups, indicating that its population may experience hurdles in preparing for and recovering after a natural disaster primarily because the available resources greatly condition the level of preparedness and capacity to cope. It was evidenced that transportation plays an enormous role in decreasing or increasing resilience in Loíza, as it will determine how fast people can access supplies and necessary services to reconstruct and recover from a natural disaster. Adaptation strategies should be outlined alongside the community to ensure an equitable and inclusive approach, as well as ensure assertive and effective outcomes for all the residents of Loíza.
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    Cycling behaviour in 17 countries across 6 continents: levels of cycling, who cycles, for what purpose, and how far?
    Goel, Rahul; Goodman, Anna; Aldred, Rachel; Nakamura, Ryota; Tatah, Lambed; Garcia, Leandro Martin Totaro; Diomedi-Zapata, Belen; de Sa, Thiago Herick; Tiwari, Geetam; de Nazelle, Audrey; Tainio, Marko; Buehler, Ralph; Gotschi, Thomas; Woodcock, James (2021-05-09)
    International comparisons of cycling behaviour have typically been limited to high-income countries and often limited to the prevalence of cycling, with lack of discussions on demographic and trip characteristics. We used a combination of city, regional, and national travel surveys from 17 countries across the six continents, ranging from years 2009 through 2019. We present a descriptive analysis of cycling behaviour including level of cycling, trip purpose and distance, and user demographics, at the city-level for 35 major cities (>1 million population) and in urbanised areas nationwide for 11 countries. The Netherlands, Japan and Germany are among the highest cycling countries and their cities among the highest cycling cities. In cities and countries with high cycling levels, cycling rates tend to be more equal between work and non-work trips, whereas in geographies with low cycling levels, cycling to work is higher than cycling for other trips. In terms of cycling distance, patterns in high- and low-cycling geographies are more similar. We found a strong positive association between the level of cycling and women's representation among cyclists. In almost all geographies with cycling mode share greater than 7% women made as many cycle trips as men, and sometimes even greater. The share of cycling trips by women is much lower in geographies with cycling mode shares less than 7%. Among the geographies with higher levels of cycling, children (<16 years) are often overrepresented. Older adults (>60 years) remain underrepresented in all geographies but have relatively better representation where levels of cycling are high. In low-cycling settings, females are underrepresented across all the age groups, and more so when older than 16 years. With increasing level of cycling, representation of females improves across all the age groups, and most significantly among children and older adults. Clustering the cities and countries into homogeneous cycling typologies reveals that high cycling levels always coincide with high representation of females and good representations of all age groups. In low-cycling settings, it is the reverse. We recommend that evaluations of cycling policies include usage by gender and age groups as benchmarks in addition to overall use. To achieve representation across different age and gender groups, making neighbourhoods cycling friendly and developing safer routes to school, should be equally high on the agenda as cycling corridors that often cater to commuting traffic.
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    Cycling through the COVID-19 Pandemic to a More Sustainable Transport Future: Evidence from Case Studies of 14 Large Bicycle-Friendly Cities in Europe and North America
    Buehler, Ralph; Pucher, John (MDPI, 2022-06-14)
    This article examines the impact of COVID-19 on cycling levels and government policies toward cycling over the period 2019 to 2021. We analyze national aggregate data from automatic bicycle counters for 13 countries in Europe and North America to determine month-by-month and year-to-year changes in cycling levels in 2020 and 2021 compared to 2019. That aggregate analysis is complemented by case studies of 14 cities in the USA, Canada, the UK, Belgium, France, Spain, and Germany. Although there was much variation over time, among countries, and among cities, cycling levels generally increased from 2019 to 2021, mainly due to growth in cycling for recreation and exercise. In contrast, daily trips to work and education declined. All 14 of the cities we examined in the case studies reported large increases in government support of cycling, both in funding as well as in infrastructure. Bikeway networks were expanded and improved, usually with protected cycling facilities that separate cyclists from motorized traffic. Other pro-cycling measures included restrictions on motor vehicles, such as reducing speed limits, excluding through traffic from residential neighborhoods, banning car access to some streets, and re-allocating roadway space to bicycles. Car-restrictive measures became politically possible due to the COVID-19 crisis.
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    The Dynamics of the Impacts of Automated Vehicles: Urban Form, Mode Choice, and Energy Demand Distribution
    Wang, Kaidi (Virginia Tech, 2021-08-24)
    The commercial deployment of automated vehicles (AVs) is around the corner. With the development of automation technology, automobile and IT companies have started to test automated vehicles. Waymo, an automated driving technology development company, has recently opened the self-driving service to the public. The advancement in this emerging mobility option also drives transportation reasearchers and urban planners to conduct automated vehicle-related research, especially to gain insights on the impact of automated vehicles (AVs) in order to inform policymaking. However, the variation with urban form, the heterogeneity of mode choice, and the impacts at disaggregated levels lead to the dynamics of the impacts of AVs, which not comprehensively understood yet. Therefore, this dissertation extends existing knowledge base by understanding the dynamics of the impacts from three perspectives: (1) examining the role of urban form in the performance of SAV systems; (2) exploring the heterogeneity of AV mode choices across regions; and (3) investigating the distribution of energy consumption in the era of AVs. To examine the first aspect, Shared AV (SAV) systems are simulated for 286 cities and the simulation outcomes are regressed on urban form variables that measure density, diversity, and design. It is suggested that the compact development, a multi-core city pattern, high level of diversity, as well as more pedestrian-oriented networks can promote the performance of SAVs measured using service efficiency, trip pooling success rate, and extra VMT generation. The AV mode choice behaviors of private conventional vehicle (PCV) users in Seattle and Knasas City metropolitan areas are examined using an interpretable machine learning framework based on an AV mode choice survey. It is suggested that attitudes and trip and mode-specific attributes are the most predictive. Positive attitudes can promote the adoption of PAVs. Longer PAV in-vehicle time encourages the residents to keep the PCVs. Longer walking distance promotes the usage of SAVs. In addition, the effects of in-vehicle time and walking distance vary across the two examined regions due to distinct urban form, transportation infrustructure and cultural backgrounds. Kansas City residents can tolerate shorter walking distance before switching to SAV choices due to the car-oriented environment while Seattle residents are more sensitive to in-vehicle travel time because of the local congestion levels. The final part of the dissertation examines the demand for energy of AVs at disaggregated levels incorporating heterogeneity of AV mode choices. A three-step framework is employed including the prediction of mode choice, the determination of vehicle trajectories, and the estimation of the demand for energy. It is suggested that the AV scenario can generate -0.36% to 2.91% extra emissions and consume 2.9% more energy if gasoline is used. The revealed distribution of traffic volume suggests that the demand for charging is concentrated around the downtown areas and on highways if AVs consume electricity. In summary, the dissertation demonstrates that there is a dynamics with regard to the impacts and performance of AVs across regions due to various urban form, infrastructure and cultural environment, and the spatial heterogeneity within cities.
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    Emotional Agents: Modeling Travel Satisfaction, Affinity, and Travel Demand  Using a Smartphone Travel Survey
    Le, Huyen Thi Khanh (Virginia Tech, 2019-06-28)
    This dissertation seeks to understand travel satisfaction, travel affinity, and other psychological factors in relation to travel demand, such as the desire for trip making, willingness to spend time traveling, and choice of travel mode. The research was based on the Mood State in Transport Environments survey of 247 Android users (about 6,000 completed trip surveys) in the Blacksburg-Roanoke, VA, Washington, DC, and Minneapolis, MN metropolitan areas from fall 2016 to spring 2018. Respondents answered an entry survey, tracked their travel for 7 days, and answered a trip survey associated with each trip. The dataset provides opportunities to examine travel and activities during travel at the within- and between-person levels. Three studies in this dissertation examined three measures of the positive utility of travel and their relationship with travel behavior. I quantified (1) the desirability of trip making, (2) the ideal travel time related to different travel characteristics, and (3) the effect of satisfaction on commute mode choice. The first study examines the patterns of travel affinity with various travel modes, trip purposes, and activities during the trip. Travel affinity was measured by asking the willingness to forgo a trip when there is an opportunity to do so. I found that this is a valid and strong measure of the positive utility of travel. Travelers were more willing to make trips when they traveled on foot or bicycle, talked with someone during the trip, and took shorter trips. Additionally, commute trips were less likely to be enjoyed as compared to other, non-commute trips. The second study focused on (1) testing the validity of the "ideal travel time" measurement and (2) measuring factors associated with the willingness to spend time traveling. I found that although ideal travel time was a strong measure of the positive utility of travel, it was very weakly associated with the desirability of trip making and satisfaction with trips. Although few people wanted zero commute time (3%), the number of trips that had zero ideal travel time was much higher (16%), indicating that the desired travel amount may vary across different trip and environmental characteristics and purpose. Ideal travel time was longer for active travel trips, leisure trips, when conducting activities during trips (e.g., talking, using the phone, looking at the landscape), when traveling with companions and during the weekend. The third study investigated the role of travel satisfaction and attitude in mode choice behavior. This is one of the very few studies that have considered the role of these psychological factors in multimodal mode choice based on revealed preference data. I found that satisfaction and attitude toward modes and travel played a significant role in the choice model; it also modified the role of travel time in the models. However, the perception of travel time usefulness was insignificant in the model. Scenario analyses based on the model results showed that it is optimal to invest in active transportation and public transit at the same time in order to shift car drivers to these sustainable modes. These studies contribute to the small but growing body of literature on the positive utility of travel and transrational decision making in transportation. It is the only study that employed a smartphone survey with a repeated measure of trips over the course of 1-2 weeks. The third study is among the earliest attempts to include satisfaction and attitude together into mode choice models. This dissertation has several implications for research and practice. First, it calls for better measurements of well-being and satisfaction. Second, models with appropriate psychological factors would more realistically resemble actual travel behavior. Including satisfaction in the choice model changes the coefficient of travel time (and potentially cost), which modifies the value of travel time savings, a basis of most benefit-cost analyses in transportation planning and engineering. Better mode choice and trip generation models will generate more reliable predictions of future infrastructure use and investment. Third, studies of travel affinity (positive utility of travel) have implications for demand modeling and management practice. Practitioners should reevaluate the effectiveness of travel demand management strategies aimed at reducing travel time and trips, such as congestion pricing (e.g., tolls), online shopping, and telecommuting.
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    Equilibriums of Paradox: Pittsburgh's Urban Renaissance through Public Transport
    Samson, Benjamin Lee (Virginia Tech, 2012-05-03)
    The city of Pittsburgh, PA has been losing population since the steel trade imploded in the 1970's. Every decade, the city lost more inhabitants and began to be hollowed out in the typical fashion of a Rust Belt city. For the first time in four decades, the city saw a rise in population in 2008. Indications show that Pittsburgh is becoming a successful post-industrial city. The average age of the population also lowered, indicating a brighter future. Pittsburgh recently has gained national distinction, being named America's "Most Livable City" by Rand McNally (2007), Forbes (2010) and The Economist(2011). With museums, theaters, a budding arts scene, and three successful professional sports teams, the city is brimming with urban amenities. In many ways, Pittsburgh has been seen as the example that other Rust Belt cities should follow if they too are to transition into the post-industrial age. However, during the challenging economic times over the past forty years, Pittsburgh has missed out on investing in public transit infrastructure. If Pittsburgh is to continue to shed its Smoky City image and further its urban renaissance, it must invest in a modern, comprehensive and integrated regional transit system. The system will act as stitching to reconnect Pittsburgh's urban fabric to its riverfronts as well act as a catalyst for redevelopment of its hollowed neighborhoods. This thesis offers a design for such a system, ranging from the macro scale of a regional network to the micro scale of hub station details. Each chapter examines the situation on a progressively smaller scale and the design principles in each scale's examples can be applied throughout the transit network.
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    Essays in Transportation and Electoral Politics
    Harmony, Xavier Joshua (Virginia Tech, 2024-03-01)
    Abstract 1 – The Importance of Transportation Policies in Local Elections Building and maintaining transportation systems is one of the most important functions of local government. It is a subject that concerns local residents, jurisdictions spend a lot of money on, and local politicians use to their political advantage. This study helps us understand how transportation issues feature in local elections. Through evaluating a dataset of 542 candidates from 219 local election races from 2022, this study explores which candidates for local office are more likely to have transportation policies, what kind of content is included in these policies, and what are the factors that make including different transportation content more or less likely. The analysis primarily uses website campaign content and a mix of qualitative and quantitative methods to answer these questions. I find a variety of factors affect the inclusion of transportation issues at the local level such as variations in governance, partisanship, and regional characteristics like a jurisdiction's size and transportation behavior. It was also evident that defining transportation issues was more common than proposing transportation policy solutions. Overall, this research provides more insight into how transportation policies are included in local elections. Abstract 2 – Saliency of Transportation Policies in State Legislative Elections: The Case of Virginia Transportation systems are expensive and directly impact important issues like climate change, equity, and quality of life. However, it is not clear how important transportation policies are in state-level elections. Using the Virginia 2021 state legislative election, this research uses candidate website data, Twitter data, and data about Virginia House of Delegates districts to answer three questions: which candidates are more likely to have transportation polices, what issues or transportation modes are included, and what factors make candidates more or less likely to focus on certain issues. Using descriptive statistics, and regression methods, this research found transportation issues varied by political party with top overall issues including transportation funding as well as expanding or improving transportation systems. Public transportation was the top non-car mode. Candidates were more likely to include transportation issues if district households had higher car ownership or a lower percentage of single occupancy vehicle commuters. Finally, differences in transportation issues could be partly explained by political party, incumbency, population density, and transportation habits. These results will be helpful for understanding how state government transportation agendas change, can better inform transportation advocacy efforts, and could help transportation professionals better understand the impact of their work. Abstract 3 – Does Voting Affect the Provision of Bus Service? Inequalities in the distribution of bus services are important to understand. This chapter adds to previous literature by exploring why inequalities exist. Specifically, does voting for elected officials affect inequalities in the delivery of bus services? This study explores this question using a quantitative approach as part of a quasi-experimental research design focusing on GoRaleigh in North Carolina and the Milwaukee County Transit System in Wisconsin. The analysis provides evidence of a relationship between voting behavior and bus service. This finding is observed across cities and elections with the relationships holding even when controlling for factors associated with a bureaucratic explanation for changing bus service, like changes to population or jobs. However, the strength of the relationship can change between elections, the type of elected official, and cities. Overall, this work provides more evidence of the politics behind transit service planning, especially the political influences of voting behavior in representative democracies.
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    Evolving Technologies Shaping Public Transit
    Epanty, Efon Mandong (Virginia Tech, 2024-02-01)
    The transit industry is changing rapidly due to technology, which in turn changes business models, ridership, travel patterns, and the transit workforce. As transit agencies introduce new technology systems, research is needed on how these systems impact demand for paratransit and on-demand mobility services. This research addresses this topic by studying the impact of technology on demand-responsive transportation and urban mobility. Over the past two decades, this sector has been transformed by cloud computing, machine learning, artificial intelligence, ridesharing, and mobility-on-demand. This dissertation explores the adoption of new technology by transit agencies and service providers, focusing on implementing app-based dynamic technologies for dispatching and scheduling demand-responsive transportation modes such as microtransit services, on-demand transit, and paratransit. Although studies on technological changes in other sectors have been conducted, public transit agencies need a more systematic approach to adopting new technology. Current literature on technology adoption in public transit focuses on the benefits and outcomes of technology adoption, with limited discussions of the challenges faced in adopting and implementing technologies. Comprehensive research on the emerging and evolving transit technological landscape is essential to bridge this gap. This research examines how transit agencies react to internal and external technological changes as their operational, tactical, and strategic operating conditions evolve. The aim is to enhance the current comprehension of the topic by providing a comprehensive overview of the technology adoption methodology and to offer practical planning and policy recommendations where possible. A mixed-methods approach was applied to explore the research questions. Transit practitioners and managers in the Washington DC region were surveyed, and the analysis techniques employed included cross-tabulation and descriptive statistics. This dissertation focuses on gaining insight into adopting real-time dynamic dispatching and scheduling, on-demand transit, and microtransit technologies, including the opinions of transit practitioners and policymakers involved in facilitating technology adoption. Specifically, the study aims to: 1) understand the impact of adopting emerging paratransit technologies; 2) investigate on-demand transit system performance outcomes under ridership, on-time performance, and operating costs, using a survey and expert interviews; and 3) investigate the use of a multicriteria decision-making approach to evaluate accessibility considerations in microtransit adoption planning and design strategies. The results suggest that current technology adoption approaches in transit can significantly enhance decision-making and transit outcomes while addressing the equity and accessibility needs of the community and maintaining coverage and route frequency. The Socio-Technical-Systems (STS) approach was applied to help understand the adoption of new technology in demand response transit. This approach provides insights into technology, accessibility, decision-making, functionality, and interchangeability, enhancing our understanding of social complexity. Additionally, this research introduces a multi-level decision-making framework to measure service performance and provides insights into the impact of transportation technology on planning, policy, and decision-making processes.
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    An Exploration of the Decline in E-Scooter Ridership after the Introduction of Mandatory E-Scooter Parking Corrals on Virginia Tech's Campus in Blacksburg, VA
    Buehler, Ralph; Broaddus, Andrea; White, Elizabeth; Sweeney, Ted; Evans, Chris (MDPI, 2022-12-23)
    We report shared e-scooter ridership and rider perceptions on Virginia Tech’s Blacksburg campus before and after introduction of mandatory e-scooter parking corrals in January 2022. The analysis relies on a panel of 131 e-scooter riders surveyed in Fall 2021 and Spring 2022. Although parking corrals were perceived favorably prior to implementation, perceptions became more negative afterwards. Respondents said corrals were not located where needed, difficult to find, fully occupied, and took too much extra time to use. After parking corrals were introduced, ridership declined 72% overall and also fell for all socio-economic subgroups. The heaviest user groups, like undergraduate males, were most likely to quit. The first study identifying desired and actual egress times for e-scooters, we found that roughly two-thirds of riders desired egress times under 2 min and one quarter under 1 min. Prior to the introduction of parking corrals, 82% of riders reported actual egress times under 2 min, and 43% under 1 min. Those who kept riding after the introduction of e-scooter corrals reported longer actual egress times and a stronger stated desire for egress times under 2 min. Communities should be careful when imposing e-scooter parking restrictions to ensure that e-scooter egress time is sufficiently low—ideally within an easy 2 min walk of popular origins and destinations.
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    Green Infrastructure in the Public Realm: Reimagining Stormwater and the Urban Fabric of Falls Church, Virginia
    Dsouza, Michelle Mary (Virginia Tech, 2023-02-21)
    Impervious surfaces are the greatest contributors to degradation of water quality and large volumes of stormwater runoff. Green infrastructure is the holistic solution to this problem which not only reduces flooding but also actively moves towards achievement of larger environmental goals. Green infrastructure has the co-benefits of reducing the heat island effect, traffic calming, beautifying the neighbourhood, improving the canopy within the city, the creation of parks and even supports economic development. The City of Falls Church is deeply concerned with the pressing matter of flood control due to the threats to human life and property in recent flooding events. The polluted waters of Falls Church also contribute to a highly impaired watershed- the Chesapeake Bay. This thesis recognizes the environmental crisis caused by polluted runoff and places equal emphasis upon reducing runoff as well as improving water quality. In order to mitigate the effects of inundation, it is most critical to intervene at the source of locations which create the most runoff and pollution. The thesis provides a systematic methodology of identifying such areas and intervening in them. The watershed which contains the downtown area of Falls Church has the greatest amount of impervious surfaces and the highest rate of stormwater runoff. The two intersecting streets of S. Maple Avenue and Annandale Road are identified as the location of intervention after tabulating a confluence of stormwater and public realm factors. S. Maple Avenue is a part of the Falls Church bike network and is also designated to become a civic great street. Meanwhile, Annandale Road has the potential to play an active role in collection and management of stormwater. Annandale Road runs along the watershed boundary as well as crosses several tributaries which are low points in the watershed. Furthermore, there is a dynamic urban character to the street as it transitions from a residential zone to the commercial zone. Both streets present excellent possibilities for road diets, pedestrianization and traffic calming which bolsters the implementation of stormwater management in the public realm.
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    Guidance and Practice in Planning Cycling Facilities in Europe—An Overview
    Schröter, Bettina; Hantschel, Sebastian; Koszowski, Caroline; Buehler, Ralph; Schepers, Paul; Weber, Johannes; Wittwer, Rico; Gerike, Regine (MDPI, 2021-08-25)
    The provision of convenient, safe and seamless facilities for cyclists is one core success factor in promoting cycling as a mode of transport. Cycling infrastructures and planning philosophies differ greatly between countries, but there is no systematic overview or comparison of similarities and dissimilarities. The aim of this study is to provide an in-depth international overview of guidance material for cycling facilities in European countries and to develop recommendations for advancing provisions for cyclists. International guidance materials for cycling facilities along street sections are collated, systemised and compared. For researchers, the findings provide background information to better understand cycling behaviour and safety. For planners, the findings support their efforts to support cycling and to improve guidance materials. The results show that, in general, countries that are just beginning to promote cycling tend to offer a greater variety of cycling infrastructures in their guidance materials than more mature cycling countries. Countries differ in whether they prefer to put cyclists on the street level or on the sidewalk and whether they mix cyclists with other user groups in the same space. There was even greater variability among countries in the criteria for selecting types of cycling facilities than in the design characteristics (width, buffer zones, etc.).
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    Heterotopia: Loose Space For an Edge City
    Babii, Volodymyr (Virginia Tech, 2017-01-26)
    In the beginning of my research I focused on transformations of the urban leftover and void space found in between buildings, street networks, parks or other institutionalized public spaces into urban places of character. By studying the spatial qualities of different places and their relation to human activities in those places I came up with the main question of my thesis: Can a space be designed loose and/or can it be loosened by design? The concept of “heterotopia”, as described by Michel Foucault in his essay “Of Other Spaces: Utopias and Heterotopias”, is a place functioning in nonhegemonic conditions, the place of “otherness” that has more layers of meaning than meet the eye. That concept proved to be the best description and the bounding frame of the design part of my research.
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    Impact of Road Proximity and other Determinants of Air Quality along Multi-Use Trails in the National Capital Region
    Tushar, Md Shazalal (Virginia Tech, 2024-06-04)
    Active travel can provide short-term and long-term health benefits and has the ability to reduce the negative externalities of vehicular traffic, for example, congestion, land consumption, and air pollution. However, exposure to air pollution is higher for pedestrians and cyclists than other road users when considering inhalation rate and travel distance. Route choice for active travel is a potential strategy to reduce the adverse impact of exposure to air pollution. Multi-use trails could be an effective way to reduce health impacts as the pollutant concentration is typically lower on trails, however, proximity to nearby roadways can deteriorate the air quality in multi-use trails. The goal of this study is to investigate the air pollutant concentrations on multi-use trails adjacent to different roadway classification and identify the factors that influence air quality in multi-use trails. I collected pollutant concentrations of PM2.5, particle number, and black carbon using mobile monitoring on an e-bike. I identified five trail routes that run parallel to an interstate highway, principal arterial, and local roads for this study and collected pollutant concentrations during morning, afternoon, and weekend afternoon peak hours. The average concentration of PM2.5, particle number, and black carbon was 15.62 µg/m3, 9,857 pt/cc, and 595.36 ng/m3 respectively among all the trail routes used for this study. I observed higher pollutant concentrations during morning peak hours than afternoon peak hours. Also, concentrations were lower on weekends than weekdays. The pollutant concentrations were different among multi-use trails based on their proximity and characteristics of nearby roadways. The pollutant concentrations significantly declined when the trail segment was 50-100 meters away as compared to segments within 50 meters of nearby interstates, freeways, or collectors. Concentrations increased significantly for trail segments having a nearby road Annual Average Daily Travel (AADT) of more than 32,000. The regression models explain 65%, 59%, and 52% of variability in the PM2.5, particle number, and black carbon concentrations respectively. Nearby road AADT and road density were found to be significant for PM2.5, particle number, and black carbon concentrations. Cooking place (rest areas with barbeque grills) and construction sites were significant and positively associated with PM2.5 concentrations. Airport and construction sites near trails showed a positive relation to the particle number concentration. Parking spaces near trails increase the concentration of black carbon along trails. This study shows the impact of roadway proximity on the air quality of trails which should be considered by municipalities while planning for multi-use trail network to mitigate health risks of pedestrians and bicyclists on trails.
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    Lenses of Connectivity: Adapting the Impact of Urban Highways on American Cities
    Hayes, Andrew Michael (Virginia Tech, 2016-09-30)
    Once thriving neighborhoods in mid-sized American cities have been decimated, scarred and disrupted by the serpentine free form highways that have touched them. This product of technological innovation from the 1950s and 60s has had a profound and disturbing affect upon American cities. The collective history, cultural rituals and organic urban fabric of life has been almost completely extinguished in these cities by the false opportunity and instant gratification that comes with so-called 'technological progress.' This, yes this, epitomizes the urban core of a majority of cities across the United States early in the early 21st century. What is to be the future legacy of these American cities upon the life of their residents? It quickly became apparent that to develop a deep understanding of this urban challenge, it was going to be necessary to carefully examine cites that have been acutely affected by urban highways. The neighborhoods at the core of these damaged American cities trudge on'.. Why? Because they have no other option'. The question currently at hand is how can these damaged neighborhoods adjacent to urban highways, and their associated cities, be regenerated? The research phase of this thesis exposed four critical elements of a thriving and organic urban neighborhood; connectivity, realness, livability and performativity. I was encouraged to focus upon and explore this notion of connectivity by my thesis committee, as it represents the element offering the most agency for the design professions. Through interrogating the [dis]connectivity of four specific neighborhoods in Baltimore, Buffalo, Richmond and St Petersburg certain operational systems began to evolve. These systems center around three critical lenses of focus; the economic, social and physical operations that occur within and adjacent to an urban neighborhood. Due to its acute condition, the Gilpin neighborhood of Richmond, Virgina was chosen as a case study to employ the lenses of connectivity through close examination and intervention.
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    A New Procedure for Scoring Rail Transit Connections to U.S. Airports
    Peterson, Mark William (Virginia Tech, 2012-04-30)
    25 airports have a connection with the local rail transit system, but each is unique. Variables such as network size, train frequency, type of airport station, time, and cost vary by airport. Both airport passengers and planners should have a technical basis of selecting which system is the most useful, efficient, and reliable. To date, there have been no scoring procedures created to rank the airports in order of quality of connection. This thesis analyzes rail transit accessibility for all 25 airports (3 of which have 2 separate transit systems) by investigating 8 characteristics, 3 of which are market factors and 5 of which are system factors. The 5 system factors are travel time difference between car and train, transit cost difference between car and train, airport/transit connection type, network size, and train frequency. The 3 market factors are rail transit mode share, business traveler percentage, and low-cost carrier percentage. A scoring system was then developed and each airport's characteristics were inputted. The airports were scored using three different methods and were subsequently evaluated to understand why airports received the scores they did. This evaluation led to a better understanding of airport transit best practices. The scoring system was used again to evaluate an airport (Washington-Dulles) undergoing radical changes to understand by what factor a score can improve. A "top 10" list of airport transit connections was produced with JFK coming in first. This method is a starting point for developing a robust system to evaluate transit connections to airports.
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    Optimizing Bike Sharing Systems: Dynamic Prediction Using Machine Learning and Statistical Techniques and Rebalancing
    Almannaa, Mohammed Hamad (Virginia Tech, 2019-05-07)
    The large increase in on-road vehicles over the years has resulted in cities facing challenges in providing high-quality transportation services. Traffic jams are a clear sign that cities are overwhelmed, and that current transportation networks and systems cannot accommodate the current demand without a change in policy, infrastructure, transportation modes, and commuter mode choice. In response to this problem, cities in a number of countries have started putting a threshold on the number of vehicles on the road by deploying a partial or complete ban on cars in the city center. For example, in Oslo, leaders have decided to completely ban privately-owned cars from its center by the end of 2019, making it the first European city to totally ban cars in the city center. Instead, public transit and cycling will be supported and encouraged in the banned-car zone, and hundreds of parking spaces in the city will be replaced by bike lanes. As a government effort to support bicycling and offer alternative transportation modes, bike-sharing systems (BSSs) have been introduced in over 50 countries. BSSs aim to encourage people to travel via bike by distributing bicycles at stations located across an area of service. Residents and visitors can borrow a bike from any station and then return it to any station near their destination. Bicycles are considered an affordable, easy-to-use, and, healthy transportation mode, and BSSs show significant transportation, environmental, and health benefits. As the use of BSSs have grown, imbalances in the system have become an issue and an obstacle for further growth. Imbalance occurs when bikers cannot drop off or pick-up a bike because the bike station is either full or empty. This problem has been investigated extensively by many researchers and policy makers, and several solutions have been proposed. There are three major ways to address the rebalancing issue: static, dynamic and incentivized. The incentivized approaches make use of the users in the balancing efforts, in which the operating company incentives them to change their destination in favor of keeping the system balanced. The other two approaches: static and dynamic, deal with the movement of bikes between stations either during or at the end of the day to overcome station imbalances. They both assume the location and number of bike stations are fixed and only the bikes can be moved. This is a realistic assumption given that current BSSs have only fixed stations. However, cities are dynamic and their geographical and economic growth affects the distribution of trips and thus constantly changing BSS user behavior. In addition, work-related bike trips cause certain stations to face a high-demand level during weekdays, while these same stations are at a low-demand level on weekends, and thus may be of little use. Moreover, fixed stations fail to accommodate big events such as football games, holidays, or sudden weather changes. This dissertation proposes a new generation of BSSs in which we assume some of the bike stations can be portable. This approach takes advantage of both types of BSSs: dock-based and dock-less. Towards this goal, a BSS optimization framework was developed at both the tactical and operational level. Specifically, the framework consists of two levels: predicting bike counts at stations using fast, online, and incremental learning approaches and then balancing the system using portable stations. The goal is to propose a framework to solve the dynamic bike sharing repositioning problem, aiming at minimizing the unmet demand, leading to increased user satisfaction and reducing repositioning/rebalancing operations. This dissertation contributes to the field in five ways. First, a multi-objective supervised clustering algorithm was developed to identify the similarity of bike-usage with respect to time events. Second, a dynamic, easy-to-interpret, rapid approach to predict bike counts at stations in a BSS was developed. Third, a univariate inventory model using a Markov chain process that provides an optimal range of bike levels at stations was created. Fourth, an investigation of the advantages of portable bike stations, using an agent-based simulation approach as a proof-of-concept was developed. Fifth, mathematical and heuristic approaches were proposed to balance bike stations.