Digital Commons Network^™

Dna Barcoding Complements Citizen Science Identifications In An Arthropod Survey At Governors Island, New York, Malky Gestetner

Dissertations and Theses

Arthropods are declining worldwide, threatened by habitat loss, climate change, and growing urbanization. Efforts to monitor arthropod biodiversity are crucial for conservation policies and for maintaining the ecosystem services provided by these animals in urban environments. Surveys of arthropods have been attempted in many New York neighborhoods, but no formal assessment has been conducted on Governors Island, which harbors 72-acres of parkland within a short boat ride away from Manhattan. This is a deficiency which this study helps to address. Following student-led collection efforts within four Governors Island sites, DNA barcoding was employed to complement specimen identification based on morphology …

China-U.S Relations: Techno‑Nationalism, Strategic Entrapment, And Taiwan., Prince Y. Munya Mr.

Dissertations and Theses

Abstract

This thesis examines how China–U.S. relations evolved from a manageable strategic rivalry into a more rigid and increasingly difficult form of competition after the Obama administration’s “Pivot to Asia.” It argues that traditional explanations such as power transition theory alone cannot fully explain the deterioration of the relationship. Instead, the study introduces the concept of techno-nationalism, where technological leadership becomes tied to national identity, economic security, and geopolitical power, particularly in areas such as semiconductors, artificial intelligence, and supply-chain security. Through historical analysis and policy tracing, the thesis develops the concept of strategic entrapment to explain how both Washington …

The Limits Of Economic Sanctions: Why Western Efforts Did Not Fully Economically Isolate Russia After 2022 Invasion Of Ukraine, Jonibek Oblokulov

Dissertations and Theses

No abstract provided.

Machine Learning Prediction Of Federal Appellate Court Outcomes: A Multi-Circuit Analysis With Administrative Law Implications, Nicky Nuertey Apenahier

Dissertations and Theses

Federal appellate courts are the final arbiters in many cases, yet systematic machine learning analysis across all twelve circuits remains largely absent from the computational law literature. With courts of appeals deciding tens of thousands of cases annually and the Supreme Court reviewing only a fraction, understanding what predicts reversal outcomes has both theoretical importance and practical consequences for litigants, attorneys, and judicial administrators. This study addresses that gap using eleven years of federal appellate decisions from the Federal Judicial Center’s Integrated Database. A systematic comparison of twenty-five machine learning models, spanning five algorithms and five class-imbalance correction strategies, identifies …

Key-Point-Based Sign Language Translation With Multi-Stream Motion Modeling And Cross-Lingual Transfer, Alex Muchiri Kagozi

Dissertations and Theses

Automatic sign language translation remains challenging because models must recover linguistic structure from complex visual motion while relying on limited annotated data. This thesis investigates whether compact skeletal key-points can serve as an effective alternative to RGB video for continuous sign language recognition and translation, motivated by the privacy, computational efficiency, and transferability of skeletal representations. To address this problem, a segmented key-point-based framework is evaluated in continuous sign language recognition (Sign2Gloss), gloss-mediated translation (Sign2Gloss2Text), gloss-free translation (Sign2Text), and transfer learning within a common modeling pipeline. The proposed framework is a motion-aware multi-stream transformer encoder. Rather than processing the signer …

Heat Misers, Snow Misers, And Cognitive Misers: The 'Nukewarm' Perceptions Of Nuclear Power, Tyler Williams

Dissertations and Theses

Rising energy demand in the United States necessitates alternatives to fossil fuels, yet renewable energy sources alone are insufficient to meet this demand. Nuclear power presents a promising option but faces persistent public hesitancy. This study examines how heuristic-based biases relate to American's risk-benefit perceptions towards nuclear power. Guided by the heuristic-systematic model. Results indicate that competence and affect are related to risk-benefit perceptions, and naturalness shows no relationship with risk perceptions but does correlate with benefit perceptions. Implications highlight the importance of affect-driven communication strategies for nuclear communicators, while also underscoring the need for participatory approaches that foster trust …

Women's Social Roles And Alcohol Use Among Military-Connected Spouses, Sheila Kathleen Mccabe Nickerson

Dissertations and Theses

Increases in women's alcohol use are an intensifying public health problem in the United States, contributing to a hidden epidemic of alcohol-related mortality. Women's alcohol consumption is often not openly discussed or recognized due to social stigma, the perception that women drink less than men, and the fact that women can experience negative health consequences from lower levels of alcohol consumption (relative to men), making the issue less visible than it actually is. A range of factors potentially influence women's drinking, including social roles (i.e., mother); yet, the literature is varied as to whether the combination of multiple-role demands/expectations fosters …

Mechanical Improvements And Control Implementation On A Biomimetic Quadruped Model, Matthew Jack Lutz

Dissertations and Theses

Robotic development started billions of years after earth first began biological prototyping. While the evolutionary process in animals is quite different from robotic prototyping, it still remains no surprise that animals remain more agile, more efficient, and more adaptable than even the most advanced engineered robots to date, simply due to the sheer length of their improvement process. While bridging this improvement gap between deficits in robots and the abilities of animals is difficult, a specific subfield of robotics engineering has attempted to do so using biomimetic robotics. At Portland State, the Agile and Adaptive Robotics Lab (AARL) studies these …

An Integrated Multivariate Econometric Modeling Framework For Risky Driving Behavior Related Crashes: Evaluating Crash Risk And Severity Across Zones, Pabitra Kumar Roy

Dissertations and Theses

Rapid advancements in crash modeling have yet to fully integrate multiple behavior-driven crash types and their severity outcomes within a single, scalable framework, specially in a way that captures the sequential nature of these behaviors where one risky action may amplify another. This study proposed an integrated multivariate econometric framework to jointly model crash frequency and severity outcomes for three major behaviorally driven crash types: alcohol-related, distraction-related, and aggressive-driving-related crashes. Specifically, using Oregon's 2022 census block group-level crash data, we propose an Integrated Multivariate Negative Binomial – Generalized Ordered Probit Fractional Split (IMNB–GOPFS) model to analyze these dimensions simultaneously while …

Leveraging High-Performance Cloud Computing To Model Underwater Acoustic Propagation And Scattering From Time-Evolving Rough Sea-Surfaces Using The Finite-Difference Time-Domain Method, James Alexander Higgins

Dissertations and Theses

This dissertation presents a two-dimensional (2D) Finite-difference Time-domain (FDTD) model for simulating underwater acoustic propagation and scattering from a one-dimensional (1D) time-evolving rough sea-surface. The techniques discussed are extendable to three spatial dimensions. Traditional acoustic modeling techniques often rely on a "frozen" sea-surface assumption, which proves inadequate for long-duration signals interacting with the time-evolving boundary at many different wave height displacements during its transit. To address this, a new FDTD update equation incorporating a variable subgrid is developed, significantly enhancing spatial accuracy at the boundary without increasing computational cost or compromising stability.

The model's accuracy is rigorously validated against established …

"I Like The Idea In Theory": Experiencing The Imperial Matrix Through Legal Gender Marker Changes And Nonbinary Disidentifications, Wynn Strange

Dissertations and Theses

Since 2018 twenty-two states and the District of Columbia have implemented administrative changes that provide a third gender option on at least one state identification document allowing nonbinary and intersex people the opportunity to select a gender marker that reflects their gender identity. This study draws from 28 interviews with agender or otherwise nonbinary people living in Maryland and California. I use queer of color and critical trans theory to consider the implications of legal gender marker changes. This research explores how social, historical, and geographical location can influence ones' awareness of, experiences with, and relation to real and imagined …

Exploring The Experiences Of White Passing And White-Assumed Latine College Students, Emanuel Magaña

Dissertations and Theses

Between 2009 and 2019 Latine college enrollment has increased, yet retention and graduation rates lag those of their white peers. While barriers for Latine students are well-documented, the influence of colorism, particularly among lighter-skinned or white passing students, remains understudied. This study utilized a qualitative case-study approach grounded in CRT and LatCrit and based on a Street Race Praxis framework. This study explored the experiences of twelve white passing and/or white-assumed Latine students at an emerging HSI in the Pacific Northwest. Using Testimonio informed approach and Counterstory, I drew from interviews, pláticas, site observations, and document analysis to create four …

From Cafes To Competitiveness: The Influence Of Amenities On Office Values And Suburban Economic Development In Portland, Or, Jihye Kang

Dissertations and Theses

This dissertation examines the spatial and economic implications of urban amenities in the formation of suburban office markets in the post-pandemic period. The research applies principles from agglomeration theory, spatial econometrics, and urban planning to analyze the statistical relationships between amenity distribution, rent formation, and location behavior across central and non-central submarkets.

The research consists of three integrated papers focused on the Portland–Vancouver–Hillsboro, OR–WA Metropolitan Statistical Area (MSA). The first paper employs spatial econometric modeling, specifically a Spatial Autoregressive Model with Autoregressive Disturbances (SARAR), to examine the relationship between proximity to cafés and office rent levels in Portland’s central business …

Online Decision Mamba, Trenton W. Ruf

Dissertations and Theses

Online in-context reinforcement learning enhances offline-trained policies through online fine-tuning. We introduce Online Decision Mamba (ODM), an architecture that replaces the attention mechanism in Online Decision Transformers (ODT) with the Mamba module to improve long-context sequence modeling and overall RL performance. We performed in-depth evaluations on MuJoCo (OpenAI Gym) and Atari benchmarks, comparing ODM against state-of-the-art offline and online baselines—including Decision Mamba (DM) and ODT. Our results show that ODM achieves competitive or superior performance, with particularly robust gains when initial datasets lack expert demonstrations. In the Qbert Atari environment, ODM shows context-length sensitivity similar to offline DM; however, we …

You Have To Cut&Walk; Before You Can Cut&Run;: Regulation Of Gene Expression By The Vitamin D Receptor (Vdr) In The Annual Killifish, Austrofundulus Limnaeus, Rosalia Tanori

Dissertations and Theses

The annual killifish, Austrofundulus limnaeus, found in ephemeral ponds in South America, possesses a remarkable ability to survive extended periods without water and oxygen. This ability is associated with developmental dormancy known as diapause. Numerous genetic and environmental factors influence the entry into diapause and tolerance to environmental stress. Among these is vitamin D3 signaling mediated by the vitamin D receptor (VDR), which plays a crucial role in regulating entry into diapause and the continuous development of an embryo in a temperature-dependent manner. Vitamin D3 signaling influences a variety of physiological processes in vertebrates. While extensively characterized in mammalian …

Spike Timing Depended Plasticity Produces Unsupervised Learning Of Synergistic Muscle Feedback In A Synthetical Neural Network, Mark Allen Pupkiewicz

Dissertations and Theses

This study investigates how type Ia feedback from muscle spindles can be organized into groups representing agonistic muscle pairs through Spike Timing Dependent Plasticity (STDP). A single degree of freedom joint is actuated with four biologically modeled muscles forming two agonistic pairs. In order to emulate the sensory dynamics of biological muscle spindles, sensors in the model record the active length and velocity states of each muscle, the two primary factors eliciting type Ia afferent responses. In biological networks, synapses from Ia sensory neurons frequently activate interneurons representing agonistic muscle sources. This research investigates whether this organization can emerge in …

An Innovative Hdm Model For Assessing Renewable Heat Energy Resources In Utility Energy Systems, Mark Alan Ryan

Dissertations and Theses

Renewable Heat Energy projects exhibit numerous unique, complex, and often conflicting characteristics, including varying project sizes, diverse energy resources, stakeholder demands, and significant challenges in energy conversion applications. Traditionally, cash flow analysis and return on investment are the most widely recognized metrics for evaluating remote energy projects. However, numerous quantitative and qualitative factors influence the overall performance and success of Renewable Heat Energy System (RHES) projects. A comprehensive approach using advanced tools is essential for assessing the factors and criteria that significantly impact these projects.

This research investigates the key quantitative and qualitative factors that contribute to the successful implementation …

Medicaid Funding And Health-Related Social Needs: A Policy Analysis, Passion Ilea

Dissertations and Theses

The U.S. has disproportionately high health care spending compared to other high-income nations and comparatively poor health outcomes. The Centers for Medicare and Medicaid Services (CMS) have recently increased emphasis on addressing Medicaid member social needs. CMS believes addressing health-related social needs (HRSN) may reduce costs and improve health outcomes for Medicaid members. CMS has begun to test theories regarding the impact of member HRSN on health care by designing federal mechanisms to address HRSN, such as in lieu of services and settings-funded services, and by encouraging state Medicaid programs to develop their own approaches, such as Flexible Services. Information …

In-Between Spaces: First-Generation College Immigrant Experiences, Silvina Alamo Sousa-Ransford

Dissertations and Theses

It is human nature to seek a sense of belonging, acceptance, and community. College students also share this desire for connection in higher education, but some face more barriers and challenges. This study examined the experiences of first-generation college students who are also immigrants. The goal was to understand how to best support students in college, including through academic advising, at a four-year research university in the Pacific Northwest. To gain insight into the students' experiences, I interviewed participants using narrative qualitative methods guided by the framework of sense of belonging and analyzed the data utilizing Bronfenbrenner's Ecological Model. The …

Development And Applications Of A Health Equity Summary Score Using The Medical Expenditure Panel Survey, Ronald R. Sanchez

Dissertations and Theses

Despite sustained national efforts, disparities in healthcare delivery persist among racial and ethnic minorities, low-income individuals, and socially at-risk populations. Monitoring modifiable aspects of care delivery, such as the structures and processes that health systems can directly improve, is a key strategy for addressing these gaps. However, most measures evaluate modifiable aspects of care delivery separately, limiting understanding of how improvements in one domain reinforce the other and how their combined effect influences equitable care.

This dissertation addresses this gap by combining patient experience and clinical quality, two modifiable aspects of care that captures how patients interact with the health …

Flow Control Tactics For Photovoltaic Modules: Coherent Structure And Heat Shedding Amplification, Sarah Elizabeth Smith

Dissertations and Theses

Solar photovoltaic systems have become the fastest growing renewable technology in the last several years. However, large-scale systems are at the mercy of their external environments, where extreme heating and wind-flung debris impact their efficiency and useable life. The work in this dissertation presents studies aimed to both understand and mitigate for these effects by identifying the underlying physics which govern them. Exploring flow control as a tactic to combat environmental heating, collective work discusses the role of turbulent fluid dynamics within large-scale systems as pertains to convective heat transfer, turbulent structure formation, and particle-laden environments. Wind tunnel experiments on …

Perspectives Of Cannabis Farmers On Intersection Of Water Access And Cannabis Frontier Constraints In Southern Oregon, Tapiwa Malvin Chabikwa

Dissertations and Theses

Cannabis farming and use are being legalized at unprecedented levels by many states in the United States. Oregon was one of the pioneer states to legalize cannabis in 2016. Although it is legalized at the state level (in Oregon), cannabis remains illegal at the federal level. Due to the quasi-legalization of cannabis, an agricultural frontier for marijuana is unfolding. Cannabis farming in Oregon has grown as there is a market and ideal weather climate for the cannabis industry to flourish. This study seeks to understand the challenges cannabis farmers face in accessing water and the socio-economic and political constraints that …

Digging Deeper With Deep Ram Networks, Andrew J. Wagner

Dissertations and Theses

While Deep Neural Networks (DNNs) have driven major breakthroughs in artificial intelligence, their internal complexity often makes their behavior hard to explain, resulting in the well-known “black box” dilemma. This thesis addresses the challenge of interpretability in DNNs and deep reinforcement learning (DRL) through two main contributions.

In Part I, we revisit and extend the use of Deep RAM Networks (DRNs) within the Arcade Learning Environment (ALE), showing that, with modern architectures and careful hyperparameter tuning, RAM-based agents can achieve performance competitive with established pixel-based baselines on Atari 2600 games, while offering additional advantages for research and analysis. We also …

Characterizing Meteorological Patterns For Oregon's Winter Elevated Pm2.5 Concentrations From 2000-2023, Arielle Golda Sherbak

Dissertations and Theses

Valleys and basins are uniquely susceptible to the buildup of air pollution during the wintertime due to cool, dense air pooling under favorable meteorological conditions, a common occurrence in the Intermountain West. In Oregon, wintertime anthropogenic air pollution is primarily from woodburning stoves and heaters and although efforts have been made to reduce wintertime pollution, stagnation events continue to result in decreased air quality. This analysis aims to understand the relationship between air pollution in six Oregon counties and the associated meteorology in the cool season (November-March) using a 2000-2023 climatology.

This is completed through a composite analysis using key …

An Evaluation Of Therapeutic Harm Reduction And Psilocybin-Assisted Therapy Within Oregon's Measure 109, Bodhi Norton

Dissertations and Theses

Despite psilocybin still being a Schedule I substance in the Federal Controlled Substance Act (OHA, 2022), Oregon voters passed Measure 109 in 2020, now codified into law as ORS457A, which allowed for the opening of psilocybin clinics for eligible clients. The passing of Measure 109 allowed for an adult-use model to be created, which is different from a therapeutic-use model. Advocates and Measure 109 framers employed the terms "harm reduction" and "mental health support" in order to secure the passing of Measure 109, but there is no specific definition of therapeutic harm reduction within M109 and ORS475A. To receive psilocybin …

Communities Of Practice: Aging, Emergency Management, And Churches In Rural Clackamas County, Oregon, Lukas Robert Aberle

Dissertations and Theses

As the population of the United States ages, questions arise of how to best care for older adults in daily life and emergency situations. This research looks at the daily activities of churches to see how they affect everyday and emergency care practices. As a collaboration with Clackamas County government, I researched the relationship between churches and care through participant observation and interviews during the summer of 2024 to understand congregations’ support for older members, the role of church congregations in emergency management, and the implications of the decline in religious participation alongside aging in the United States. I found …

Sex Worker Stigma, Morality And Ambivalent Sexism, Emily Kate Kinzel

Dissertations and Theses

Sex worker stigma has received limited attention in psychological research. Although stigma is often theorized to relate to moral concerns, the relationship between stigma and moral concerns has not been empirically established. This study aims to address these gaps by developing a measurement tool for attitudes towards sex workers--specifically an implicit association test (IAT)--and explore the relationships between sex worker stigma, moral concerns, and ambivalent sexism. Mock policy questions on the criminalization and punishment of sex workers were also included to approximate behavioral intentions of participants. A cross-sectional correlational study of 168 community members found evidence that both moral concerns …

Exploring Impacts Of Diversity Ideologies On Allyship (Intergroup Responsiveness), Fiona Nguyen

Dissertations and Theses

Colorblindness and multiculturalism are widely studied diversity ideologies that reflect prominent attitudes about how diversity should be understood and managed, as they can help predict individual behavior. Colorblindness proposes that distinct group identities should be ignored, and can be used to exclude minoritized groups and downplay racial minorities' experiences, whereas multiculturalism embraces and values group differences, can foster inclusive environments for minority groups, and leads to positive intergroup outcomes such as reduced prejudice. Despite much research dedicated to exploring the intergroup outcomes of diversity ideologies, few studies have examined their impacts on specific interpersonal interactions, particularly allyship. Research has defined …

What Kinds Of Experiences And Activities Contribute To College Students' Sense Of Purpose? A Mixed-Methods Study, Katlyn Rochelle Viers

Dissertations and Theses

For many young people, attending college is a core marker of the transition to emerging adulthood. Some students thrive in college while others become lost, confused, or seem to be just marking their time. Some researchers have hypothesized that one thing that can help students take advantage of their college experience is if they are firmly anchored in their own life goals and sense of purpose. The primary goal of this study is to contribute to knowledge about the role of a sense of purpose in college students' development, including not only its potential benefits to their academic functioning and …

From Either-Or To All Together: Integrating Universal And Relativistic Approaches To Belonging And Engagement In The First Year Of Middle School, Kristina Shiann Tucker

Dissertations and Theses

Schools are designed to foster growth and learning while promoting positive educational outcomes for all students. Yet, there is some evidence that the education system is not meeting the needs of all students, nor are achievement outcomes the same for everyone. Some of the identified challenges seem to be developmentally based, whereas others are evident among different demographic subgroups. Developmental differences are apparent in many aspects of academic functioning, such as student motivation and engagement, which peak when students enter school and normatively decline, relatively steadily, throughout students' educational careers. Demographic disparities are even more pronounced, represented, for example, in …