Transportation Commons^™

Data Files: The Role Of Bus Stop Features In Facilitating Accessibility, Keith Batholomew, Ja Young Kim, Divya Chandrasekhar, Reid Ewing, Arlie Adkins, Samuel Jensen

TREC Datasets and Databases

These datasets support a final report published on NITC’s website “The Role of Bus Stop Features in Facilitating Accessibility”: https://nitc.trec.pdx.edu/research/project/1214.

The DOI for the final report is: https://dx.doi.org/10.15760/trec.254.

Impact Of Regular And Narrow Av-Exclusive Lanes On Manual Driver Behavior, Sahar Ghanipoor Machiani, Aryan Sohrabi, Arash Jahangiri

Mineta Transportation Institute

This study attempts to answer the question of how a narrow (9-ft) lane dedicated to Automated Vehicles (AVs) would affect the behavior of drivers in the adjacent lane to the right. To this end, a custom driving simulator environment was designed mimicking the Interstate 15 smart corridor in San Diego. A group of participants was assigned to drive next to the simulated 9-ft narrow lane while a control group was assigned to drive next to a regular 12-ft AV lane. Driver behavior was analyzed by measuring the mean lane position, mean speed, and mental effort (self-reported/subjective measure). In addition to …

Promoting Transit-Oriented Developments By Addressing Barriers Related To Land Use, Zoning, And Value Capture, Shishir Mathur, Aaron Gatdula

Mineta Transportation Institute

This study advances land use, transportation planning, and public finance research by identifying: a) the various land use, zoning, and value capture-related barriers to the construction of transit-oriented developments (TODs); and b) the major strategies that are commonly used or could be used to address these barriers. The value capture (VC) tools include joint development projects, tax increment financing, special assessments, lease/sale of land or air rights, and impact fees. The research finds that while a large proportion of jurisdictions across the US have TODs, land use, zoning, and VC-related barriers often impede their construction. Most transit agencies are not …

Online Traffic Signal Control Through Sample-Based Constrained Optimization, Srishti Dhamija, Alolika Gon, Pradeep Varakantham, William Yeoh

Research Collection School Of Computing and Information Systems

Traffic congestion reduces productivity of individuals by increasing time spent in traffic and also increases pollution. To reduce traffic congestion by better handling dynamic traffic patterns, recent work has focused on online traffic signal control. Typically, the objective in traffic signal control is to minimize expected delay over all vehicles given the uncertainty associated with the vehicle turn movements at intersections. In order to ensure responsiveness in decision making, a typical approach is to compute a schedule that minimizes the delay for the expected scenario of vehicle movements instead of minimizing expected delay over the feasible vehicle movement scenarios. Such …

An Equity Focused Study On The Trip Temporal Distributions Of Vulnerable Road Users, Santiago Espinosa Wild

Civil and Environmental Engineering Master's Project Reports

The United States is a megadiverse nation with a transportation system that, for decades, was designed to serve primarily able-bodied, white, male motorists. This legacy creates a situation in which varying socio-demographic groups experience the transportation system differently with contrasting safety, accessibility, and convenience outcomes. This project introduces descriptive statistics and binary logistic models that provide transportation professionals and policy makers with a quantitative understanding on how, why, and when certain socio-demographic groups are more likely to engage in a trip. This project provides tools to measure and understand the equity implications of a wide array of transportation policy decisions. …

The Role Of Bus Stop Features In Facilitating Accessibility, Keith Bartholomew, Ja Young Kim, Divya Chandrasekhar, Reid Ewing, Arlie Adkins, Samuel Jensen

TREC Final Reports

Although transit decision-makers and riders generally favor improving bus stops by adding shelters, benches, and similar features, it is unclear the impact such features have on transit demand and there has been little research that measures these impacts. This study examines the link between stop improvements and changes in stop-level boardings on scheduled-service buses and in ADA paratransit demand in the Salt Lake City, UT, metropolitan area between 2014 and 2017. The study also investigates current bus stop improvement practices of leading transit agencies nationwide. The study uses a number of quantitative and qualitative techniques, including propensity score matching, propensity …

Reducing Vehicle Miles Traveled, Encouraging Walk Trips, And Facilitating Efficient Trip Chains Through Polycentric Development, Reid Ewing, Keunhyun Park, Sadegh Sabouri, Torrey Lyons, Keuntae Kim, Dong-Ah Choi, Katherine Daly, Roya Etminani Ghasrodashti

TREC Final Reports

Compact development can result in many benefits for communities and residents. Areas can connect compact developments through high-quality transportation options, creating a network of centers, or a “polycentric” region. This development pattern is very popular in Europe and is linked to significant benefits. Salt Lake County has organically developed several small centers, and with the right strategies could continue to fuel this kind of growth. The metropolitan planning organization (MPO) for the region, the Wasatch Front Regional Council, has been planning for polycentric development since the Wasatch Choice for 2040 Vision was released in 2010. Our research is aimed at …

Regional Transportation Goals: Reducing Sprawl Through Interconnected Centers, Reid Ewing

TREC Project Briefs

A “polycentric” region is a network of compact developments (centers) that are connected with each other through high-quality transportation options. As the antidote to sprawling suburbs, compact centers can encourage all the things that sprawl discourages: public health, environmental sustainability, social cohesion, and economic diversity. But how can metropolitan planning organizations ensure that their regional plans will actually meet these goals? Polycentric development has been advocated by urban and transportation planners for more than a decade. However, effective practice must be backed by solid research, and to date there has been little or no research that quantifies the transportation benefits …

Non-Conventional Vehicles As A Way Towards Carbon Neutrality In Iceland, Julia Sokolowska

Independent Study Project (ISP) Collection

Paris Agreement’s chief objective is to protect the Earth and its inhabitants from a point of no return, when the effects of climate change will be so intense that they will shift the equilibrium of ecosystems. The distinctiveness of this international environmental treaty is that it does not impose climate change mitigation measures, but rather allows nation states to create their own set of measures, the NDCs, to reach the global warming of ‘well below 2oC’ by the end of the century. Thus, Iceland has submitted its own NDC, the Climate Action Plan 2018-2030, which has an ambitious goal of …

Deep Reinforcement Learning Approach To Solve Dynamic Vehicle Routing Problem With Stochastic Customers, Waldy Joe, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

In real-world urban logistics operations, changes to the routes and tasks occur in response to dynamic events. To ensure customers’ demands are met, planners need to make these changes quickly (sometimes instantaneously). This paper proposes the formulation of a dynamic vehicle routing problem with time windows and both known and stochastic customers as a route-based Markov Decision Process. We propose a solution approach that combines Deep Reinforcement Learning (specifically neural networks-based TemporalDifference learning with experience replay) to approximate the value function and a routing heuristic based on Simulated Annealing, called DRLSA. Our approach enables optimized re-routing decision to be generated …

Freight Demand Model For Southern California Freeways With Owner–Operator Truck Drivers, Joseph J. Kim, Samuel Dominguez, Luis Diaz

Mineta Transportation Institute

This study evaluates the demand for truck-only toll lanes on Southern California freeways with owner–operator truck drivers. The study implemented the stated preference survey method to estimate the value placed by drivers on time, reliability, and safety measures using various scenarios geared towards assessing those values. The project team met face-to-face with owner- operator 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 31 survey responses is obtained and used for statistical data analysis using analysis of variable (ANOVA) and two …

Southern California Regional Workforce Development Needs Assessment For The Transportation And Supply Chain Industry Sectors, Tom O’Brien, Deanna Matsumoto, Diana Sanchez, Caitlin Mace, Elizabeth Warren, Eleni Hala, Tyler Reeb

Mineta Transportation Institute

COVID-19 brought the public’s attention to the critical value of transportation and supply chain workers as lifelines to access food and other supplies. This report examines essential job skills required of the middle-skill workforce (workers with more than a high school degree, but less than a four-year college degree). Many of these middle-skill transportation and supply chain jobs are what the Federal Reserve Bank defines as “opportunity occupations” -- jobs that pay above median wages and can be accessible to those without a four-year college degree. This report lays out the complex landscape of selected technological disruptions of the supply …

Road Traffic Accident Research In India: A Scientometric Study From 1977 To 2020, Dr. Jayaprakash G. Hugar, Dr. Mirza Muhammad Naseer, Dr. Abu Waris, Muhammad Ajmal Khan

Library Philosophy and Practice (e-journal)

This study carried out the scientometric analysis of road traffic accident research in India from 1977 to 2020. It aimed to examine type of publications with their citations and usage, the year wise publication and citation growth, most preferred journals, authors’ preference of keywords used, collaboration of Indian authors, authorship pattern and most prolific authors, and top contributing organizations. During 44 years of study, 1,132 research items were published and indexed in Web of Science (WoS) bibliographic database. Analysis discovered that number of publications increased from one (0.08%) in 1977 to 182 (16.07%) in 2018 and observed good progress in …

Traffic Scorecard In Mountain West Cities, Kelliann Beavers, Eshaan Vakil, Katie M. Gilbertson, Caitlin J. Saladino, William E. Brown Jr.

Transportation & Infrastructure

This fact sheet presents congestion and mobility trends in 14 Mountain West cities as compiled by INRIX Research and author Trevor Reed, in the Global Traffic Scorecard, March 2020. The INRIX Global Traffic Scorecard examines the impact of vehicle travel on 975 congested cities in the world; this fact sheet focuses on the Mountain West, providing insight on the ranking and impacts of congestion. This fact sheet also supplements INRIX’s scorecard with population data from the U.S. Census Bureau to provide context for the rankings.

Webinar: A National Scan Of Bike Share Equity Programs: Best Practices And Lessons Learned, Nathan Mcneil, John Macarthur, Adriel Thornton

TREC Webinar Series

Connecting with cities and bike share operators from across the United States, Portland State University conducted a nationwide scan on what programs and initiatives were running to address equity in bike share. The report “National Scan of Bike Share Equity Programs” documents responses from over 70 bike share systems. This resource will help cities and operators navigate the range of actions that have been implemented to make bike share systems more equitable, examine successful strategies employed across the U.S., and understand how those successes (and challenges) are being measured and articulated. In doing so, we hope the report helps bike …

Comparing The Promise And Reality Of E-Scooters: A Critical Assessment Of Equity Improvements And Mode-Shift, Michael Glenn Mcqueen

Dissertations and Theses

In just three years, e-scooters have substantially disrupted and altered the urban mobility landscape. Throughout this period, they have been commonly touted as part of a larger micromobility solution that promises to erase equity barriers and solve the first-mile/last-mile problem. However, few studies in the nascent e-scooter literature have considered these claims. In this study, we surveyed students at Portland State University (n = 1,968) about the role that e-scooters, among other modes, played in meeting their general and university-related travel needs. We then estimated models that incorporated demographics, travel behavior, and latent attitudes distilled using exploratory factor analysis (EFA). …

Characteristics Of Effective Metropolitan Areawide Public Transit: A Comparison Of European, Canadian, And Australian Case Studies, Michelle Derobertis, Christopher E. Ferrell, Richard W. Lee, John M. Eells

Mineta Transportation Institute

This research project investigates the replicable characteristics, policies, and practices of successful metropolitan areawide public transportation networks that contribute to high usage and make transit an effective competitor to the private motor vehicle. The research method involves the qualitative and quantitative analysis of ten international (non-U.S.) case studies. The principal methods employed were web-based research and data collection, as well as telephone interviews with transit agency staff or regional planners as needed. The case studies were limited to developed western countries with similar metropolitan conditions to those in the United States.

This research focuses on key characteristics of highly effective …

Analysis Of The Benefits Of Green Streets, Christopher E. Ferrell, John M. Eells, Richard W. Lee, Reyhane Hosseinzade

Mineta Transportation Institute

Green streets offer many potential benefits that include improving water quality, absorbing carbon (sequestration), and reducing urban heat island effects. This report summarizes: (1) the research team’s analysis of 14 tools calculating green streets benefits; and (2) the results of applying the most promising calculators to a select group of green streets case studies. The researchers are affiliated with the Mineta Transportation Institute, which serves the California Department of Transportation (“Caltrans”). The report presents the results of the case study analyses, with an emphasis on carbon sequestration benefits and improvements to pedestrian levels of service (PLOS).

Trees absorb carbon dioxide …

Measuring Success For Safe Routes To School Programs, Carole Turley Voulgaris, Serena Alexander, Reyahne Hosseinzade, James Jimenez, Katherine Lee, Anurag Pande

Mineta Transportation Institute

Safe Routes to School (SRTS) programs aim to increase the share of students who commute to school by active modes (e.g., walking and cycling). The goal of this work was to assess the effectiveness of SRTS programs. Towards that end, we analyzed the California Household Travel Survey (CHTS) data from the four counties in the San Francisco Bay area. We estimated logistic regression model(s) to predict the likelihood that a child commutes to school by active modes based on the presence of an SRTS program and controlling for individual, household, and tract characteristics. Findings indicate that longer trip distance and …

The Potential Of Green Infrastructure In Mitigating Flood Impacts On The Mobility Of Low Income And Minority Neighborhoods, Courtney Crosson, Yinan Zhang, Daoqin Tong

TREC Project Briefs

Short-term flooding from extreme storm events poses a serious transportation challenge in U.S. cities. This problem—which is anticipated to grow over the next century with our global climate crisis—is often hardest on vulnerable populations, including low-income and minority neighborhoods. This project advances national research methods for assessing flood vulnerability and prioritizing transportation improvement investments to ensure that no community is left stranded when the next flood occurs.