Social and Behavioral Sciences Commons^™

A Survey Of North American Electric Bicycle Owners, Cameron Steven Bennett

Dissertations and Theses

Rapid recent growth in the popularity of electric bicycles (e-bikes) has captured the attention of transportation researchers and policymakers seeking safe, sustainable, and active alternatives to conventional transportation modes. This thesis presents an investigation of e-bike owners in North America, complementing previous efforts in 2013 and 2017, and suggests implications for North American transportation planning.

An online survey was distributed to e-bike owners in the United States and Canada through email outreach, purchase incentive programs, and social media. The survey included questions on the respondents’ demographics, e-bikes, purchase decisions, travel behavior, perceptions of e-bikes, crash experience, maintenance needs, and receipt …

Current Vehicle Fleet Inventory And Future Implementation Of A Centralized Electric Fleet At Portland State University, Dane Kovaleski

Environmental Science and Management Professional Master's Project Reports

As the effects of climate change continue to impact the world, many institutions have developed climate action goals to reduce their effects on the environment. Portland State University (PSU) has committed to an 80% reduction of greenhouse gas emissions by 2030 and carbon neutrality by 2040. A part of this commitment must include looking at the contributions of transportation on campus to reduce carbon emissions. According to a greenhouse gas emissions report done by the Campus Planning and Sustainability Office in 2016, transportation contributed to 12% of total greenhouse gas emissions on campus.

This project aims to evaluate the management …

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 …

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 …

Transportation Mode Choice Behavior In The Era Of Autonomous Vehicles: The Application Of Discrete Choice Modeling And Machine Learning, Sangwan Lee

Dissertations and Theses

New mobility technologies, such as shared mobility services (e.g., car-sharing) and, more importantly, autonomous vehicles (AVs), continue to evolve. The supply-side advancement will likely disrupt and transform transportation mode choice behaviors, and create a new paradigm since they are emerging and becoming increasingly feasible alternatives to the existing modes of transportation. Accordingly, this dissertation employs discrete choice modeling (DCM) and machine learning (ML) using a U.S. nationwide stated choice experiment to understand how travelers adopt new transportation modes or continue to use conventional modes of transportation.

This dissertation consists of three papers. The first examines future market shares of each …

Adoption And Use Of E-Grocery Shopping In The Context Of The Covid-19 Pandemic: Implications For Transport Systems And Beyond, Gabriella Abou-Zeid

Dissertations and Theses

In 2020, the COVID-19 pandemic drastically impacted travel for in-person shopping, commute trips, global supply chains, and food business operations. Previously mundane tasks, like shopping for food and household items, became markedly different as new social distancing and mask guidelines were put in place to mitigate the spread of COVID-19. Concurrently, e-commerce sales in the U.S. skyrocketed. E-grocery pickup and delivery services saw unprecedented expansions. The adoption and use of e-grocery services have implications for equity and mobility, although the nature of the relationship of e-grocery to the latter is still unclear. Enhancing our understanding of the drivers of (and …

The Mode Less Traveled: Exploring Bicyclist Identity In Portland, Or, Christopher Johnson

Dissertations and Theses

This study explores bicyclist as a social identity in Portland, OR and a relatively under researched topic in the existing literature about transportation mode choice. The results indicate that bicyclists in Portland do have an understanding of what it means to be a bicyclist and particularly the normative behaviors associated with that social identity. Results also indicate that barriers to entry into this social group are quite low but the path to becoming someone who regularly chooses bicycling as a mode of transportation is not straightforward and is fraught with barriers that could easily discourage new group members. Bicyclists in …

Short-Term And Long-Term Effects Of New Light Rail Transit Service On Transit Ridership And Traffic Congestion At Two Geographical Levels, Huajie Yang

Dissertations and Theses

This dissertation quantitatively examines the effect of new Light Rail Transit (LRT) services on transit ridership and traffic congestion over time at two different geographical levels: at the corridor level, this study conducts case studies of two LRT lines in the Portland, Oregon region; at the regional level, this study uses a synthetic control method to construct a "synthetic" control Urbanized Area (UA) that closely approximates the counterfactual transit ridership and traffic congestion scenario in the absence of light rail project in three UAs across America. The results of the corridor-level study suggest that both LRT lines increased transit ridership …

Examining Bicycle And Motorized Vehicle Speeds And Their Relationships In The Context Of Urban Roadways, Jaclyn Sue Schaefer

Dissertations and Theses

This thesis presents a compilation of papers exploring passenger car and bicycle speeds through their interactions with each other and with urban roadway factors.

First, following a concern raised in part of the traffic literature that a large mode shift toward bicycling may cause travel time delays and potentially exacerbate congestion instead of alleviate it unless bicycle lanes are installed, an empirical study detailing how the presence of bicycles on urban roads without bicycle lanes may affect passenger car speeds is presented. Pneumatic tube data from six predominantly low speed, low volume roads in Portland, Oregon were utilized to identify …

Methodologies To Quantify Transit Performance Metrics At The System-Level Using High-Resolution Gps, Stop-Level, And Gtfs Archived Transit Data, Travis Bradley Glick

Dissertations and Theses

Performance metrics have typically focused at two main scales: a microscopic scale that focuses on specific locations, time-periods, and trips; and, a macroscopic scale that averages metrics over longer times, entire routes, and networks. When applied to entire transit systems, microscopic methodologies often have computational limitations while macroscopic methodologies ascribe artificial uniformity to non-uniform analysis areas. These limitations highlight the need for a middle approach.

This dissertation presents a mesoscopic analysis based around timepoint-segments, which are a novel application of an existing system for many transit agencies. For this research, routes are divided into a consecutive group of bus stops …

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. …

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). …

"I Should Have Moved Somewhere Else": The Impacts Of Gentrification On Transportation And Social Support For Black Working-Poor Families In Portland, Oregon, Steven Anthony Howland

Dissertations and Theses

Portland has faced a mass displacement of Black households from the historically segregated area of Albina through various phases of urban renewal, urban deterioration, and gentrification. A substantial number of them have moved to East Portland, a suburban segment of the City of Portland that was unincorporated county land prior to the 1990's. As Black people have left Albina, the roots of Blackness there have eroded from the area as businesses and churches catering to them have also closed as a result of lost patrons.

In this study I interviewed 27 low-income working-age Black people with children with the sample …

Portland’S I-5 Expansion: Evaluating The Environmental And Cultural Impact Of Odot's Rose Quarter Improvement Plan, Mason Ashmore

University Honors Theses

To this day highway expansion remains one of the primary techniques employed to combat urban automobile congestion during peak hours. This paper examines the cultural and environmental shortcomings of Portland, Oregon's I-5 highway expansion project. Research for this paper primarily cites existing academic studies relating to highway expansion, Portland's complicated relationship with urban renewal, and highway expansion alternatives. The evidence suggests that Oregon's expansion project would have less than optimal impact and the resources could be used better elsewhere.

The Impacts Of The Bicycle Network On Bicycling Activity: A Longitudinal Multi-City Approach, Wei Shi

Dissertations and Theses

Bicycling is a promising approach to improve health, environment, and economic development of urban places. Theoretically, a bicycle network's component goes beyond lanes and paths, and would generate greater impacts than the sum of its parts. However, most previous research focused on how individual types of bicycle-related infrastructure could promote bicycling. Few empirical studies investigated how bicycle networks impact bicycling activity. This project attempts to address this question. Specifically, how to properly measure bicycle networks, and what impacts bicycle networks have on bicycling activity, e.g. bike ridership and bike mode choice, across different cities and longitudinally.

To address the first …

Spatial Analysis Of Burglary And Robbery Crime Concentration Near Mass-Transit In Portland, Bryce Edward Barthuly

Dissertations and Theses

The relationship between mass-transit and the concentration of burglary and robbery crimes is inconsistent within the available literature in environmental criminology. A number of studies have provided evidence of crime concentration at and near mass transit locations where paths intersect, referred to as a node. These empirical studies bring in environmental criminology theory with the idea that crime is clustered, and the pattern of the concentrations is substantially influenced by how and why people travel and move in a city. It is suggested that public transit allows for a large proportion of the population to move around the community along …

Evaluating Project Assessment Techniques For High-Profile Transportation Projects Development And Delivery: Case Of State Departments Of Transportation (Dots) In The United States, Rafaa Ibrahim Khalifa

Dissertations and Theses

Time delays and cost overruns in construction projects are generally due to factors such as inappropriate planning, design errors, unexpected site conditions, inadvisable tools selection, change scope, weather conditions, lack of resources, and other project changes. Time delays and cost overruns are of concern to most project managers, owners, and governments. These elements of time and cost are two of the critical defects that impact the construction project delivery. These defects can lead to project failures and to various negative issues like increasing in disagreements among the project team, the contractor, suppliers, and the owner.

State Departments of Transportation (DOTs) …

The Influence Of Shared Mobility And Transportation Policies On Vehicle Ownership: Analysis Of Multifamily Residents In Portland, Oregon, Edgar Bertini Ruas

Dissertations and Theses

Since the beginning of the 21st Century, the world has seen the rapid development of the so-called "sharing economy" or collaborative consumption (Botsman, 2010). One of the first areas affected by the shared economy is vehicle ownership. With the emergence of several new providers of mobility services, such as Uber and car2go, there has been the promise of changes to the traditional way of owning and using a vehicle (Wong, Hensher, & Mulley, 2017). One potential consequence of shared mobility services is the reduction in vehicle ownership. At the same time, cities are trying to anticipate these changes by reducing …

Social Equity In Transit Service: Toward Social And Environmental Justice In Transportation, Torrey Lyons

TREC Theses and Dissertations

This dissertation explores social equity as it applies to public transportation. Transit has long been considered a tool to alleviate inequity by limiting the effects of spatial mismatch and providing access to opportunity to disadvantaged populations. This theory, however, has not been adequately proven empirically. The first chapter of this dissertation tests the theory that spatial mismatch is moderated by quality transit service. We do this by taking a cross section of the largest urban areas in the United States and applying structural equation modeling to identify relationships between exogenous and endogenous factors. We find that higher quality transit service …

Utilitarian Skateboarding: Insight Into An Emergent Mode Of Mobility, Michael Joseph Harpool

Dissertations and Theses

In recent years research and planning efforts to enhance the conditions and opportunities for active transportation modes have increased significantly; however, these efforts have primarily focused on pedestrians and bicyclists. Skateboarding and other alternative modes of mobility remain an untapped potential for healthy and sustainable travel. This research addresses numerous knowledge gaps in the literature on utilitarian skateboarding under the larger umbrella of active transportation. Analysis of online survey results and semi-structured interviews with skateboarders in Portland, OR provides insight into the motivations and barriers of traveling by skateboard and the demographics and perceptions of skateboard commuters. Like bicyclists and …

Recent Advances In Activity-Based Travel Demand Models For Greater Flexibility, Kihong Kim

Dissertations and Theses

Most existing activity-based travel demand models are implemented in a tour-based microsimulation framework. Due to the significant computational and data storage benefits, the demand microsimulation allows a greater amount of flexibility in terms of demographic market segmentation, temporal scale, and spatial resolution, and thus the models can represent a wider range of travel behavior aspects associated with various policies and scenarios. This dissertation proposes three innovative methodologies, one for each of the three key dimensions, to fulfill the greater level of details toward a more mature state of activity-based travel demand models.

Exploring The Determinants Of Vulnerable Road Users' Crash Severity In State Roads, Àlvaro Alfonso Caviedes Cómbita

Dissertations and Theses

Pedestrians and bicyclists are the most vulnerable road users and suffer the most severe consequences when crashes take place. An extensive literature is available for crash severity in terms of driver safety, but fewer studies have explored non-motorized users' crash severity. Furthermore, most research efforts have examined pedestrian and bicyclist crash severity in urban areas. This study focuses on state roads (mostly outside major urban areas) and aims to identify contributing risk factors of fatal and severe crashes involving pedestrians and bicyclists in state roads. Two ordinal regression models were developed (one for pedestrian and the other for bicyclist crashes) …

Utilizing High-Resolution Archived Transit Data To Study Before-And-After Travel-Speed And Travel-Time Conditions, Travis Bradley Glick

Dissertations and Theses

Travel times, operating speeds, and service reliability influence costs and service attractiveness. This paper outlines an approach to quantify how these metrics change after a modification of roadway design or transit routes using archived transit data. The Tri-County Metropolitan Transportation District of Oregon (TriMet), Portland's public transportation provider, archives automatic vehicle location (AVL) data for all buses as part of their bus dispatch system (BDS). This research combines three types of AVL data (stop event, stop disturbance, and high-resolution) to create a detailed account of transit behavior; this probe data gives insights into the behavior of transit as well as …

Assessing The Impact Of Land Use And Travel On Carbon Dioxide Emissions In Portland, Oregon, Zakari Mumuni

Dissertations and Theses

The negative consequences of sprawling metropolitan regions have attracted attention in both academia and in practice regarding how to better design settlements and alter travel behavior in a quest to curtail vehicle emissions. Studies that have attempted to understand the nexus between land use, travel and vehicle emissions have not been able to address the issue of self-selection in a satisfactory manner. Self-selection occurs when households choose their residential location based, in part, on expected travel behavior. This non-random experience makes the use of traditional regression frameworks that strongly rely on random sampling, unsuitable. This replication study's purpose was to …

"Are We Building Biking Solidarity": Gendered, Racial, And Spatial Barriers To Bicycling In Portland, Oregon, Kyla Jean Tompkins

Dissertations and Theses

Although Portland, Oregon is widely regarded as a "bike friendly" city, its bike equity remains in question. This thesis explores the barriers to biking that women and people of color face in Portland. This research uses feminist geography scholarship to understand how cycling spaces are unequal for marginalized cyclists. Using data from 28 in-depth, semi-structured interviews with infrequent and marginalized cyclists, I found that gender and race inequalities shape their barriers to biking. A hegemonic white, elite, and masculine bike culture controls the domination of cycling spaces. Women's gendered spatial inequalities are shaped by their childrearing demands, geography of fear, …

Exploring The Positive Utility Of Travel And Mode Choice, Patrick Allen Singleton

Dissertations and Theses

Why do people travel? Underlying most travel behavior research is the derived-demand paradigm of travel analysis, which assumes that travel demand is derived from the demand for spatially separated activities, traveling is a means to an end (reaching destinations), and travel time is a disutility to be minimized. In contrast, the "positive utility of travel" (PUT) concept suggests that travel may not be inherently disliked and could instead provide benefits or be motivated by desires for travel-based multitasking, positive emotions, or fulfillment. The PUT idea assembles several concepts relevant to travel behavior: utility maximization, motivation theory, multitasking, and subjective well-being. …

Explaining Unequal Transportation Outcomes In A Gentrifying City: The Example Of Portland, Oregon, Eugenio Arriaga Cordero

Dissertations and Theses

This dissertation examines unequal outcomes of urban transportation policies in the neoliberal era. It focuses on inequalities in the Portland, Oregon metro area between 1994 and 2011 as measured in three key areas: 1) access to public transit; 2) the journey-to-work; and 3) "household-serving" trips. Growing concern over the harmful impacts from an increasing dependence on cars has led planners in the U.S. to encourage a modal shift from private car to public transit, bicycling, and walking. The required policies to make this modal shift possible, however, might inadvertently be benefiting "choice" riders at the cost of transport disadvantaged groups. …

Land Use Mix And Pedestrian Travel Behavior: Advancements In Conceptualization And Measurement, Steven Robert Gehrke

Dissertations and Theses

Smart growth policies have often emphasized the importance of land use mix as an intervention beholding of lasting urban planning and public health benefits. Past transportation-land use research has identified potential efficiency gains achieved by mixed-use neighborhoods and the subsequent shortening of trip lengths; whereas, public health research has accredited increased land use mixing as an effective policy for facilitating greater physical activity. However, despite the celebrated transportation, land use, and health benefits of improved land use mixing and the extent of topical attention, no consensus has been reached regarding the conceptualization and measurement of this key smart growth principle …

The Effects Of Frequency Of Social Interaction, Social Cohesion, Age, And The Built Environment On Walking, Gretchen Allison Luhr

Dissertations and Theses

The purpose of this dissertation was to explore, through a social ecological framework, the multifaceted effects of the neighborhood environment by investigating how dimensions of both the built environment and the neighborhood social context may interact to influence walking. Aesthetics, land use mix, crime, and pedestrian infrastructure were considered with respect to built environment walkability, and the neighborhood social context was conceptualized using measures of both social cohesion and social interaction with neighbors. This research used data from an Environmental Protection Agency (EPA)-funded study of 748 adults (18 years of age and older) residing in the Lents neighborhood in Portland, …

Exploring Length-Based Vehicle Count Data, Byad Ahmed

Civil and Environmental Engineering Master's Project Reports

The development of Intelligent Transportation Systems (ITS) requires high-quality traffic information within most urban areas worldwide, and under growing pressure for improving traffic management, there has been an increasing urge to collecting and monitoring of traffic data. One of the most reliable and recommended technology for drive thru or traffic control is the loop vehicle detection system. On the Portland freeway system, new software has been installed that allows the reporting of vehicle length in bins. This research investigates the use of this data (length based) by exploring time series analyses of the vehicle counts as freight and non-freight movement.