Transportation Commons^™

Imitation Improvement Learning For Large-Scale Capacitated Vehicle Routing Problems, The Viet Bui, Tien Mai

Research Collection School Of Computing and Information Systems

Recent works using deep reinforcement learning (RL) to solve routing problems such as the capacitated vehicle routing problem (CVRP) have focused on improvement learning-based methods, which involve improving a given solution until it becomes near-optimal. Although adequate solutions can be achieved for small problem instances, their efficiency degrades for large-scale ones. In this work, we propose a newimprovement learning-based framework based on imitation learning where classical heuristics serve as experts to encourage the policy model to mimic and produce similar or better solutions. Moreover, to improve scalability, we propose Clockwise Clustering, a novel augmented framework for decomposing large-scale CVRP into …

A Lightweight Privacy-Preserving Path Selection Scheme In Vanets, Guojun Wang, Huijie Yang

Research Collection School Of Computing and Information Systems

With the rapid development of edge computing, artificial intelligence and other technologies, intelligent transportation services in the vehicular ad hoc networks (VANETs) such as in-vehicle navigation and distress alert are increasingly being widely used in life. Currently, road navigation is an essential service in the vehicle network. However, when a user employs the road navigation service, his private data maybe exposed to roadside nodes. Meanwhile, when the trusted authorization sends the navigation route data to the user, the user can obtain all the road data. Especially, other unrequested data might be related to the military. Therefore, how to achieve secure …

Traffic-Related Pedestrian Deaths In The Mountain West, 2022, Miguel Soriano Ralston, Caitlin J. Saladino, William E. Brown Jr.

Transportation & Infrastructure

This fact sheet examines data from Smarth Growth America’s report, “Dangerous By Design, 2022,” which reports on traffic deaths throughout the United States. This fact sheet highlights pedestrian deaths as well as deaths among specific groups based on age, race, ethnicity, and media household income between 2016 and 2020 in the Mountain West: Arizona, Colorado, Nevada, New Mexico, and Utah. This fact sheet builds upon a 2020 fact sheet, titled “Traffic-Related Pedestrian Deaths in the Sun Belt Region,” which examined Smart Growth America’s assessment of pedestrian safety for the years 2008 to 2017.

Transportation Behavior Among Older Vietnamese Immigrants In The Dallas-Fort Worth Metroplex: Well-Being, Geospatial Mobility, And Potential Indicators For Ride Providers’ Geospatial Burden, Rebecca L. Mauldin, Stephen Mattingly, Mahshid Haque, John P. Connolly, Latisha Thomas, Zachary Tarbet, Farzana Chowdhury, Rupal Parekh

TREC Final Reports

Nearly 4.6 million immigrants aged 65 and older live in the United States. This population is expected to more than triple in size by 2050. A lack of culturally appropriate transportation solutions for older immigrants creates disparities in access to services for older immigrant populations, increasing their risk of social isolation and reduced physical and mental health. A growing number of older immigrants live in low-density urban environments, which are characterized by high automobile dependency and limited public transportation. In these environments, older immigrants are likely to depend on others to provide private transportation. Negative aspects of this reliance on …

Sustaining Multimodal Choices: Examining Travel Behavior For Non-Work Trips Beyond Covid-19, Yizhao Yang, Rebecca Lewis

TREC Final Reports

Increasing the usage of sustainable travel modes requires changes in both environmental and psychological dimensions. A knowledge gap exists concerning the mechanism via which various factors interact to shape travel decision. Gaining such knowledge requires our ability to examine people’s behavioral adjustment in reaction to environmental and psychological changes or interventions.

This project uses COVID-19 as a natural experiment, treating the significant disruption induced by the pandemic as an intervention to study changes in travel behaviors and adoption of different travel choices following the COVID pandemic. This project builds upon a 2020 study conducted by the PI’s. It adopts a …

Economic Evaluation Of Route Choice Characteristics For Company Truck Drivers And Owner-Operator Truck Drivers In Southern California Freeways, Joseph J. Kim, Jose Alejandro Arroyo Turcios

Mineta Transportation Institute Publications

To contribute to the understanding of freeway capacity and financing options, this study evaluates the demand for truck-only toll lanes on Southern California freeways. The study implemented surveys to both company truck drivers and owner-operator truck drivers to estimate the value they place on time, reliability, and safety measures. The research team met face-to-face with both types of truck drivers near the Ports of Los Angeles and Long Beach to understand the drivers’ perspectives regarding truck-only toll lanes on Southern California freeways. A data set containing 45 surveys out of 62 survey responses were used for statistical analysis. The results …

Pavement Condition Survey Using Drone Technology, Lerose Lane, Dingxin Cheng

Mineta Transportation Institute Publications

Timely repairs of pavement defects are essential in protecting both public road and highway systems. Identification of pavement distresses is necessary for planning pavement repairs. This has previously been performed by engineers surveying the roadways visually in the field. As drone usage has progressed, it has become clear that drones are a valuable tool to enhance visual documentation, improve project communication, and provide various data for processing. The use of drone technology has improved both the speed and accuracy of capturing data. Available software has allowed the data to be processed and analyzed in an office environment. This report summarizes …

Enhancing Older Adults’ Mobility In Active Living And Tiered Living Communities, Yongping Zhang, Carol Kachadoorian, Wen Cheng, Edward Clay

Mineta Transportation Institute Publications

The U.S. population is aging rapidly. As people get older, they increasingly face issues such as increased susceptibility to injuries and the need to be assisted with many day-to-day activities. Older adults have the opportunity to opt-in to live in an older adult community (OAC) based on their needs and capabilities. This study comprehensively reviews existing governing development regulations and design criteria related to the older adults’ communities, conducts surveys among people involved with some of these communities in California, and recommends improvements to community design for active living and tiered living communities. This study proposes a new scoring system …

Curriculum Evaluation Of The Academy Of Global Logistics Program: Connections To Stem Education, Ann Y. Kim, Tyler Reeb, Jaylee Jordan, Youngjin Song

Mineta Transportation Institute Publications

The Academy of Global Logistics (AGL) is a career technical education program developed in collaboration with the Port of Long Beach and the Long Beach Unified School District and with support from the Center for International Trade and Transportation. Students enrolled in the program, implemented at a high school in Long Beach, CA, learn global logistics and supply chain management over the course of their high school career. The program culminates in a capstone project that is evaluated by industry leaders. This research project applies qualitative coding methods to find connections between the AGL curriculum and CA mathematics and science …

Optimization Of Station-Skip In A Cyclic Express Subway Service, Jingfeng Yang, Hai Wang, Jiangang Jin

Research Collection School Of Computing and Information Systems

With rapid population growth and increasing demand for urban mobility, metropolitan areas such as Singapore, Tokyo, and Shanghai are increasingly dependent on public transport systems. Various strategies are proposed to improve the service quality and capacity of bus and subway systems. Express trains—i.e., trains that skip certain stations—are commonly used because they can travel at higher speeds, potentially reduce travel time, and serve more passengers. In this paper, we study cyclic express subway service (CESS), in which express trains provide routine transport service with cyclic (periodic) station-skip patterns that can be used in daily service. We propose an exact Mixed …

Central Of Georgia Railway Records, Zach S. Henderson Library Special Collections

Finding Aids

This collection consists of materials spanning 1941-1947 and includes business records and correspondence of the Central of Georgia Railway Company as well as detailed reports of employees’ United States military service during World War II. These reports include employee military records, interviews conducted by Central of Georgia Railway Company of veteran employees, and letters expressing their gratitude for their service in the war. Find this collection in the University libraries' catalog.

Public Acceptance Of Guidance And Regulations For Space Flight Participation, Cory Trunkhill, Robert Joslin, Joseph Keebler

Journal of Aviation Technology and Engineering

Space flight participants are not professional astronauts and not subject to the rules and guidance covering space flight crewmembers. Ordinal logistic regression of survey data was utilized to explore public acceptance of current medical screening recommendations and regulations for safety risk and implied liability for civil space flight participation. Independent variables constituted participant demographic representations while dependent variables represented current Federal Aviation Administration guidance and regulations. Odds ratios were derived based on the demographic categories to interpret likelihood of acceptance for the criteria. Significant likely acceptance of guidance and regulations was found for five of twelve demographic variables influencing public …

A Gridded Co2 Emissions Inventory For Portland, Or, James Eckhardt Powell

Dissertations and Theses

Here we develop a new high resolution inventory of CO₂ emissions for the three Oregon counties which comprise the bulk of the City of Portland, Oregon, USA. Locally curated and long-running data collection efforts for on-road traffic activity and emission rates are used to model on-road emissions, and a new survey of the area's natural gas network informs the building energy model. The inventory estimates total emissions of CO₂ for each hour of the year 2018 in the on-road, residential, and commercial building sectors at 1 km² resolution. The onroad inventory compares to within 3% with an …

Explore Regional Variation In The Effects Of Built Environment On Driving With High Resolution U.S. Nationwide Data, Liming Wang

PSU Transportation Seminars

There have been numerous studies on the relationship between travel behavior and built environment over the last few decades. Prior studies have mostly focused on producing point estimates of model coefficients and ended up with a wide range of estimates for the built environment elasticity of travel behavior, including household Vehicle Miles Traveled. With few exceptions, previous studies use data from a single region or a small number of regions, and thus are not able to sufficiently investigate the regional variation in built environment elasticity.

On the other hand, a few papers have addressed the heterogeneity of elasticity among different …

Historic Downtown Streetscape Plan Price City, Utah, Patricia Beckert

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The idea of a small-town Main Street has profound meaning within the American culture that has prevailed for the past two centuries. Historically, Main Street serves as the beating heart of a community, a place where economic, social, cultural, and civic activities are centered (Francaviglia, 1996; Main Street America, n.d.). Since the beginning of the 19th century, many factors have led to the decline of Main Streets, and despite a variety of efforts from different stakeholders, that decline has only intensified in recent decades (Isenberg, 2008; Orvell, 2014 Howard, 2015). In 1980, after a three-year project conducted by the National …

The Use And Influence Of Health Indicators In Municipal Transportation Plans, Kelly Christine Rodgers

Dissertations and Theses

Transportation is an important social determinant of health that shapes the places where people "live, learn, work, and play" to the extent that an individual's zip code better predicts their health than their genetic code. Researchers and practitioners have called for the use of health indicators in transportation as one way to integrate public health concerns into transportation. The underlying hope is that new organizational routines, such as measuring and tracking indicators, can translate policy goals into policy practice. However, it is unclear how indicators are used and what impact they have on policy--the creation or modification of policies and …

Land Use Analysis On Vertiports Based On A Case Study Of The San Francisco Bay Area, Wenbin Wei, Kerry Rohrmeier, Tiffany Martinez, Michael Winans, Heungseok Park

Mineta Transportation Institute Publications

Vertiport research and development trails in the emerging commercial air taxi sector known as Advanced Air Mobility (AAM). Published scholarship remains limited as federal, state, and local governments have yet to create or implement policies for the rapidly progressing larger AAM ecosystem, which is designed around autonomous electric vehicle takeoff and landing aircraft. With the potential for frequent low altitude flights, long-range planning must demonstrate awareness, knowledge, and utilization of geographic information science to select safe and just vertiport locations. This study summarizes the AAM literature and offers planners a set of stakeholder-informed parameters to use in a no-cost preliminary …

Preconstruction Support Cost Hours Estimating On Caltrans Pavement Rehabilitation Projects, Nigel Blampied, Tariq Shehab, Elhami Nasr, Laxmi Sindhu Samudrala

Mineta Transportation Institute Publications

Because the construction phase accounts for the majority of project costs for pavement rehabilitation projects, most research on infrastructure project cost estimating focuses on that phase, rather than on the preconstruction phases. Nevertheless, costs incurred prior to construction, referred to in this report as "preconstruction costs" are significant and worthy of consideration (See Section 2.1 of the report for a more detailed and precise definition of preconstruction). In the 20202021 fiscal year, for instance, the California Department of Transportation (Caltrans) spent more than $169 million on preconstruction work for pavement rehabilitation projects. This report presents the results of a study …

Experimental Investigation Of The Self-Healing Potential Of Bacteria For Sustainable Concrete Structures, Pitiporn Asvapathanagul, Simone Galano, Andrea Calabrese, Mehran Rahmani, Maggie Ly, Daniela Flores, Michael Hernandez, Nicholas Banuelos

Mineta Transportation Institute Publications

Although concrete is the most widely used building material in the world, its limited tensile strength makes cracking a common phenomenon in concrete elements. This study investigates the potential of autonomous self-healing as an eco-friendly and lowcost method to increase the durability of concrete. The crack-healing potential of different types of high-alkaline-tolerant bacteria or calcite-precipitation microorganisms is investigated. High-alkaline-tolerant bacteria and calcite-precipitation microorganisms were used to retrofit lab-fractured concrete samples. The samples healed with each of these bacteria groups were cast and tested under compressive load up to failure to measure the compressive strength of the concrete samples. The outcomes …

The Distributional Impacts Of Transportation Networks In China, Lin Ma, Tang Yang

Research Collection School Of Economics

This paper evaluates the distributional impacts of transportation networks in China.We show that the quality of roads and railroads vary substantially over time and space, and ignoring these variations biases the estimates of travel time. To account for quality differences, we construct a new panel dataset and approximate quality using the design speed of roads and railroads that varies by vintage, class, and terrain at the pixel level. We then build a dynamic spatial general equilibrium model that allows for multiple modes and routes of transportation and forward-looking migration decision.We find aggregate welfare gain and less spatial income inequality led …