Transportation Commons^™

Exploring The Effects Of Meaningful Tactile Display On Perception And Preference In Automated Vehicles, Kimberly D. Martinez, Gaojian Huang

Mineta Transportation Institute

There is an existing issue in human-machine interaction, such that drivers of semi-autonomous vehicles are still required to take over control of the vehicle during system limitations. A possible solution may lie in tactile displays, which can present status, direction, and position information while avoiding sensory (e.g., visual and auditory) channels overload to reliably help drivers make timely decisions and execute actions to successfully take over. However, limited work has investigated the effects of meaningful tactile signals on takeover performance. This study synthesizes literature investigating the effects of tactile displays on takeover performance in automated vehicles and conducts a human-subject …

Are There Transit Deserts In Europe? A Study Focusing On Four European Cases Through Publicly Available Data, Yefu Chen, Junfeng Jiao

Research Collection College of Integrative Studies

Public transit has been proven as an affordable travel method, while the inequitable distribution is a rising concern among practitioners and researchers. A transit desert, based on the demand and supply concept in measuring the mismatch in allocating the level of public transit service, has proved its ability to be applied in cases across countries. According to this concept, this study investigated transit deserts in four cases in Europe. Results indicate that the public transit system in Grand Paris and Madrid are superior due to a smaller population living in areas where public transit cannot meet the demand. Moreover, we …

Understanding Covid-19’S Impact On Local Transportation Revenue –A Mid-Crisis View From Experts, Asha Weinstein Agrawal, Serena Alexander, Ashley M. Hooper

Mineta Transportation Institute

When COVID-19 swept into the United States in early 2020, it upended two patterns of behavior critical to transportation funding: how people traveled and where economic activity occurred. This study explored how, one year into the pandemic, experts in California believed that the COVID-19 pandemic was impacting local transportation budgets. We interviewed 34 funding experts who represented local transportation and public works departments, state officials, and municipal finance experts. In these conversations, conducted from December 2020 to March 2021, we asked interviewees how they saw COVID-19 impacting their overall local transportation budgets in the short and long term as well …

Large Eddy Simulations Of Wind Shear From Passing Vehicles Under A Freeway Overpass, Hamid Rahai, Assma Begum

Mineta Transportation Institute

California is moving toward a 100% clean energy future, and expanded wind energy will be a major component of the state’s future energy portfolio. Innovations in wind energy resources will move California closer to achieving its goal. To gain a better understanding of transient pressure and the wind shear generated at the bridge poles from passing vehicles, this study performed large-eddy simulations of a vehicle (also called an Ahmed body) moving under a freeway overpass at a distance of 0.75 w (width) from the bridge poles. Results include transient contours of mean velocity, turbulent kinetic energy, vorticity, and pressure around …

Understanding The Safety And Usability Of Personal Vehicles For Non-Driving Individuals With Disabilities And Their Families/Care Providers, Anil R. Kumar, Hannah Bowman

Mineta Transportation Institute

The connections between shared personal vehicles of individuals with disabilities (IWDs) and their household family members play an important role in the mobility, overall health, and well-being of all involved actors, yet this topic remains mostly overlooked within publicly available research. Families that include a non-driving IWD are more likely to be low-income, and often struggle with the costs of operating a family car but, due to insufficient public transportation options, they own vehicles despite their prohibitive cost. This exploratory study utilized the Systems Engineering Initiative for Patient Safety (SEIPS) model, a framework focused on assessing the interplaying sociotechnical factors …

Lawbreaker: An Approach For Specifying Traffic Laws And Fuzzing Autonomous Vehicles, Yang Sun, Christopher M. Poskitt, Jun Sun, Yuqi Chen, Zijiang Yang

Research Collection School Of Computing and Information Systems

Autonomous driving systems (ADSs) must be tested thoroughly before they can be deployed in autonomous vehicles. High-fidelity simulators allow them to be tested against diverse scenarios, including those that are difficult to recreate in real-world testing grounds. While previous approaches have shown that test cases can be generated automatically, they tend to focus on weak oracles (e.g. reaching the destination without collisions) without assessing whether the journey itself was undertaken safely and satisfied the law. In this work, we propose LawBreaker, an automated framework for testing ADSs against real-world traffic laws, which is designed to be compatible with different scenario …

Port Of Portland’S Marine Terminal 6 Contribution To Regional Economic Development, Lewison Lem

PSU Transportation Seminars

Container cargo shipping service returned to the Port of Portland in Oregon in January 2020 with the regular weekly SM Line service, following more than three years of no container shipping service. Following the global supply chain changes associated with COVID -19, the number of monthly vessel calls at the Port of Portland’s deep-water berth at Terminal 6 has increased regularly to 12 vessel calls in January of 2022. In March of 2022, the largest containership to transit the Columbia river – at 1,100 feet length with capacity of 8,200 containers – arrived at the Port of Portland.

The return …

Statistical Inference For Multimodal Travel Time Reliability, Avinash Unnikrishnan, Miguel Figliozzi, Subhash C. Kochar

TREC Final Reports

Travel time reliability is a key metric of interest to practitioners and researchers because it affects travel choice and the economic competitiveness of urban areas. This research focuses on three travel time reliability metrics – buffer index, modified buffer index, and the relative width of travel time distributions. The key novel contributions of this research include using the multivariate delta method to prove that the sampling distributions of the three travel time reliability metrics are asymptotically normal. The asymptotic standard error for the three reliability metrics is derived. The asymptotic normality and the standard error result are used to arrive …

Impacts Of City-Level Parking Cash-Out And Commuter Benefits Ordinances, Gabriella Abou-Zeid, Allen Greenberg

PSU Transportation Seminars

For many workers, the decision to drive to work is an economically rational one that minimizes their commute costs. The vast majority of employers offer free workplace parking, with few in comparison offering benefits for transit, walking, biking, or other means of commuting. In effect, employers are incentivizing a behavior that increases roadway congestion, reduces physical activity, and increases emissions. Moreover, since lower-income households are less likely to own and have access to a private vehicle than moderate and higher-income households, free parking is a financial benefit that many lower-income employees cannot access.

Researchers from ICF and the Federal Highway …

Community Transportation Academy: Course Curriculum And Implementation Handbook, Nathan Mcneil, Keith Bartholomew

TREC Final Reports

A Community Transportation Academy (CTA) is a course that harnesses the knowledge, technical expertise and passions of practicing transportation professionals in a city to immerse a cohort of interested and dedicated community members in transportation issues over a two to three month curriculum.

The CTA curriculum was developed by drawing from the Portland Traffic and Transportation (PTT or Portland CTA) course, along with the Wasatch Transportation Academy (WTA or Wasatch CTA, which was inspired by the Portland course). Planning academy courses in cities around the country are also good models to look to for how to structure and operate such …

Charging Drivers By The Gallon Vs. The Mile: An Equity Analysis By Geography And Income In California, Samuel Speroni, Asha Weinstein Agrawal, Michael Manville, Brian D. Taylor

Mineta Transportation Institute

This study used data from the 2017 National Household Travel Survey California Add-On sample to explore how replacing the current state vehicle fuel tax with a flat-per-mile-rate road-user charge (RUC) would affect costs for different kinds of households. We first estimated how household vehicle fuel efficiency, mileage, and fuel tax expenditures vary by geography (rural vs. urban) and by income. These findings were then used to estimate how much different types of households pay in the current per-gallon state fuel tax, what they would pay if the state were to replace fuel taxes with a flat-rate road-usage charge (RUC) that …

Strategizing Battery Swap Service: Self-Operation Or Authorization?, Zhaojun Yang, Quanlong Lei, Jun Sun, Xu Hu, Yali Zhang

Information Systems Faculty Publications

Electric vehicle (EV) charging is still time-consuming compared with traditional vehicle refueling, making many consumers hesitant to make the switch. As a solution, battery swapping allows EVs to get energized within minutes. As economies like China embrace the emerging battery swap market, relevant automakers face strategic choices between self-operation and authorization. This study establishes game-theoretic models of a duopoly EV market comprising two automakers and a battery swap market involving an additional third-party operator. Each automaker may run its own battery swap service entirely or license at least part of it to the third-party operator. The results suggest that authorization …

Damage Detection And Damage Localization In Bridges With Low-Density Instrumentations Using The Wave-Method: Application To A Shake-Table Tested Bridge, Mehran Rahmani, Xintong Ji, Sovann Reach Kiet

Mineta Transportation Institute

This study presents a major development to the wave method, a methodology used for structural identification and monitoring. The research team tested the method for use in structural damage detection and damage localization in bridges, the latter being a challenging task. The main goal was to assess capability of the improved method by applying it to a shake-table-tested prototype bridge with sparse instrumentation. The bridge was a 4-span reinforced concrete structure comprising two columns at each bent (6 columns total) and a flat slab. It was tested to failure using seven biaxial excitations at its base. Availability of a robust …

Twilytics: A Social Perception Analysis Of Public Transit Systems During The Covid-19 Pandemic, Egbe-Etu Etu, Imokhai Tenebe, Ankur Parma, Likhitha Yelamanchili, Dang Minh Nhu Nguyen, Louis Tran, Ihor Markevych

Mineta Transportation Institute

In the United States, public transit ridership in 2020 declined by 79% compared to 2019 levels. With lockdowns implemented during the early days of the pandemic, direct human-to-human interactions migrated to virtual platforms (e.g., Facebook, Twitter, and Reddit). Social media platforms have aided researchers in answering numerous questions about current societal dilemmas, including COVID-19. This study investigates the public’s perception of transit systems via a social media analysis given the emergence of vaccines and other COVID-19 preventive measures. Findings revealed themes of fear and confusion concerning the use of public transportation during the pandemic. The public had doubts regarding the …

Routes To Lower Greenhouse Gas Emissions From Freight Transportation In The City Of San José, Serena Alexander, Kyle Laveroni, Maxwell Friedman, Janani Thiagrajan

Mineta Transportation Institute

Freight represents approximately 30% of all transportation-related emissions in the U.S., but local climate action plans (CAPs) and freight plans often place limited emphasis on freight emissions reduction strategies. The objective of this report is to examine and present strategies for the City of San José, California to reduce GHG emissions from freight. The authors conducted a geospatial analysis of freight data related to San José, and an analysis of relevant literature and successful freight reduction strategies implemented globally. The report also provides key objectives and generalized strategies to reduce GHG emissions from freight as well as specific recommendations for …

Towards An Optimal Bus Frequency Scheduling: When The Waiting Time Matters, Songsong Mo, Zhifeng Bao, Baihua Zheng, Zhiyong Peng

Research Collection School Of Computing and Information Systems

Reorganizing bus frequencies to cater for actual travel demands can significantly save the cost of the public transport system. This paper studies the bus frequency optimization problem considering the user satisfaction. Specifically, for the first time to our best knowledge, we study how to schedule the buses such that the total number of passengers who could receive their bus services within the waiting time threshold can be maximized. We propose two variants of the problem, FAST and FASTCO, to cater for different application needs and prove that both are NP-hard. To solve FAST effectively and efficiently, we first present an …

Learning To Solve Multiple-Tsp With Time Window And Rejections Via Deep Reinforcement Learning, Rongkai Zhang, Cong Zhang, Zhiguang Cao, Wen Song, Puay Siew Tan, Jie Zhang, Bihan Wen, Justin Dauwels

Research Collection School Of Computing and Information Systems

We propose a manager-worker framework (the implementation of our model is publically available at: https://github.com/zcaicaros/manager-worker-mtsptwr) based on deep reinforcement learning to tackle a hard yet nontrivial variant of Travelling Salesman Problem (TSP), i.e. multiple-vehicle TSP with time window and rejections (mTSPTWR), where customers who cannot be served before the deadline are subject to rejections. Particularly, in the proposed framework, a manager agent learns to divide mTSPTWR into sub-routing tasks by assigning customers to each vehicle via a Graph Isomorphism Network (GIN) based policy network. A worker agent learns to solve sub-routing tasks by minimizing the cost in terms of both …

Study On Ships’ Routeing System At Yuxingnao Waters Of Zhoushan Coastal, Qinglong Hao

World Maritime University Dissertations

No abstract provided.

Research On Uncertainties And Challenges Of Cyber Security In Maritime Industry, Qianrong Chen

World Maritime University Dissertations

No abstract provided.

A Study On Legal Issues Of Unmanned Ship Maritime Regulation, Qingbao Zhang

World Maritime University Dissertations

No abstract provided.