Digital Commons Network^™

Factors Influencing Non-Perennial Stream Initiation In The Mt. Hood National Forest, Allison Bast

Dissertations and Theses

Historically, non-perennial headwater streams have been overlooked due to their small size and infrequent flow regimes, often leading to them not being recognized as legitimate streams, despite scientific evidence that has shown these streams significantly affect the quality of downstream waters. To combat this issue, environmental managers need to be able to accurately identify and delineate the origins of these streams; however, despite decades of research, an accurate, universal method for predicting how and where these streams commence has yet to be developed. Early studies conducted in steep, humid environments, identified a strong inverse linear relationship between the size of …

Comparative Analysis Of Bacterial Recbcd And Sbcc-Sbcd Systems And The Yeast Mre11-Rad50 Complex During Dna Replication, Tannos Seyedjavadi

Dissertations and Theses

Accurate completion of DNA replication when forks converge is essential for genome stability. In Escherichia coli, several proteins have been identified including RecG, ExoI, RecBCD, and SbcCD, that contribute to completing replication, and loss of these factors causes genetic instability. Eukaryotes encode proteins with homology to several E. coli completion enzymes. Mre11–Rad50 complex is structurally and functionally conserved with bacterial SbcCD, and Rrm3 shares homologous motifs with bacterial RecBCD. These proteins are often described as being involved in homologous double strand break repair. Whether they are also conserved and play a similar role as their E. coli counterparts in …

Degree Assortativity And Estimation Of Degree Distribution In A Contact Network Of People Who Inject Drugs, Peter Geissert

Dissertations and Theses

This dissertation analyzes data from a respondent driven sampling (RDS) study of people who inject drugs in Portland, OR.  The objective was to assess assumptions for the use of weighted estimators to estimate a population physical contact (syringe sharing) network degree distribution.

Visualization of degree distribution for social and physical networks, Kolmogorov-Smirnov tests of difference, and kernel tests of equivalence were used for comparison of distributions. Spearman's rho and GAM non-parametric regression models were used to test for association and assess non-monotonic relationship. The validity of Markov chain assumptions for RDS was assessed using a transition matrix, Markov chain graphs, …

God's Not Neutral: Narrative Tropes, Spiritual Warfare, And The Construction Of Evangelical Political Identity In American Christian Fiction, Evelyn L. Mccullough

Dissertations and Theses

Evangelical Christian fiction has reached tens of millions of readers and viewers during the most sustained period of evangelical political mobilization in American history, yet its narrative construction remains largely unexamined. This study asks how recurrent tropes in this genre build the attitudinal and emotional preconditions for political engagement. Combining systematic qualitative content analysis of eight texts spanning four decades (1986–2024) with Critical Discourse Analysis grounded in van Dijk's sociocognitive framework, it traces how storytelling devices connect theological belief to political behavior. The analysis reveals a single organizing logic: the corpus holds one regressive heroic disposition constant while making it …

Extending W-Event Differential Privacy To The Publish-Subscribe Framework, Jacob Jerome Olinger

Dissertations and Theses

Internet of Things (IoT) devices have become ubiquitous, permeating both enterprises and homes, and they increasingly rely on publish-subscribe (pub-sub) frameworks that give subscribers real-time, high-fidelity access to device data. For privacy and confidentiality, however, today's pub-sub systems largely stop at channel-level authentication, encryption, and access-control lists. These protect data in transit and restrict who may receive it, but place no quantitative limit on what a subscriber with legitimate access to messages can infer about its publishers.

We close this gap by extending w-event differential privacy to the pub-sub setting. We generalize it from count queries to any aggregate …

Omoiyari In The Performance Of American Learners Of Japanese: An Analysis Of Second Culture Compilation And Pragmatic Transfer, Shizuka Fukuo

Dissertations and Theses

This thesis examines omoiyari (consideration for others) as a Japanese cultural theme by examining how it is enacted by native Japanese speakers and American learners of Japanese during an invitation scenario. L2 learners' incorporation of the target culture's linguistic and behavioral norms is essential to fully participate in ways that read as natural in that culture. However, relatively little research has examined the extent to which L2 learners are able to enact culturally embedded norms in L2 interaction. Furthermore, little attention has been paid to explaining the cultural theme of omoiyari as it is enacted in an invitation role-play provides …

Representing Post-Fire Reality: An Empirically Informed Temperature Index Approach To Post-Fire Hydrologic Modeling In Oregon's Western Cascades, Logan Hastings

Dissertations and Theses

The invaluable water resources stored in snowpack face mounting threats from rising temperatures, drought, shifts in precipitation regimes, and increased fire frequency, which pose challenges to operational hydrologic modeling in Oregon's sensitive maritime snowpacks. The gridded temperature index (GTI) approach in operational models like the Hydrological Engineering Center's Hydrologic Modeling System (HEC-HMS) from the U.S. Army Corps of Engineers remains in common use for its minimal data requirements, but how GTI parameterizations should adapt to post-fire conditions is largely unknown.

This research assessed the impact of the 2020 Lionshead Fire on HEC-HMS performance in the North Santiam River basin across …

Insurance: A Hidden Tool In The Fire Adapted Community Toolbox?, Michael Patrick Wilshire

Dissertations and Theses

Increased costs associated with wildfire activity in the Western United States has raised concern about the long term stability of homeowners insurance. One popular approach to reducing the risk of catastrophic wildfire is the completion of Firewise behaviors on residential properties. I explored homeowner experiences with homeowners insurance, and asked if rising insurance premiums and policy non-renewals are affecting homeowners' Firewise behaviors. I surveyed homeowners living in the Wildland Urban Interface (WUI) in Deschutes County, Oregon to understand their experiences with homeowners insurance, past Firewise actions, and intentions to complete Firewise actions in the near future. Most homeowners surveyed have …

Unmanned Aerial Support Program In Portland Police Bureau: A Case Study, Eiryn Renouard

Dissertations and Theses

With the Portland Police Bureau (PPB) adopting drone technology in 2024 as a tactical tool, officers have begun to experience change in the way they approach their roles as they learn to work in conjunction with this new technology. Known as the Unmanned Aerial Support program (UAS), this drone program is embedded into PPB's patrol unit. The recency of the program offers an opportunity to examine how a new program using new technology builds its culture and impacts the perspectives and behaviors of its participating officers. By interviewing officers and conducting field observations of the officers and drones in action, …

Near-Field Acoustic Microscope With Normal Force Metrology Capability, Kacharat Supichayanggoon

Dissertations and Theses

This dissertation introduces quartz tuning fork (QTF) based Shear-force Near-field Acoustic Microscopy (SANM) and Whispering Gallery Acoustic Microscopy (WGAS) systems, upgraded this time with Atomic Force Microscopy (AFM) capability to also monitor the vertical force component involved in shear force interactions. This enhanced system aims at studying nano-sized confined fluids under shear, with an emphasis on finding correlations between the fluid's a) viscoelastic properties and b) near-field acoustic wave emission capability. In the current SANM/WGAS/AFM system addressed here, the confined fluid is constituted by the water meniscus that bridges the gap between the apex of a laterally …

Developing Field And Spaceflight Microscopy, Nikki Johnston

Dissertations and Theses

Designing for spaceflight favors the reduction of unnecessary features and cost-cutting, whether thisbe computation, hardware, or procedure. Resources are spent toward fortification and mission success over convenience. Such design goals paired with the relatively smaller budgets of academia lead us to do as much as we can in-house and use open-source as much as we can without compromising mission success. We also believe that thoroughly testing technology in extreme environments on earth is necessary for the success of a flight instrument. We focus on microscopy for life detection. I have spent my time here learning methods of hand-building microscopes to …

Advancing The Oresat Adcs: Design & Implementation Of An Open-Source Reaction Wheel System, Chris Kane-Pardy

Dissertations and Theses

Reaction wheels provide the primary means of precision attitude control for many CubeSat attitude determination and control systems by exchanging angular momentum with the spacecraft body. As the Portland State Aerospace Society's OreSat spacecraft transitioned from a 2U to a 3U configuration, the increased spacecraft inertia reduced the attitude control authority available from the legacy reaction wheel system. This thesis addresses that challenge through the redesign of the reaction wheel system and the development of a deterministic embedded controller and experimental framework for evaluating brushless motor commutation strategies under identical operating conditions.

The redesigned system combines an analytically sized flywheel, …

Trapped In Transition: Structural Change And Political Dynamics In Middle-Income Countries, Gabriel Duvidovich

Dissertations and Theses

The middle-income trap literature has examined why relatively few middle-income countries transition to high-income status. A range of explanations has been proposed, but the political dimension has often been overlooked. Studies that take a political perspective often focus on institutional form rather than the state’s ability to effectively implement policy. This study addresses this gap by bringing political capacity to the center of the analysis. It argues that political capacity appears important for the productive upgrading required for sustained growth in middle-income economies and shapes economic growth trajectories across countries at different income levels.

The empirical analysis uses country-period panel …

Temperature And Hydrologic Context Influence Methane Variability In A Low-Salinity Marsh, Zoie Brauser

Dissertations and Theses

Coastal wetlands are biogeochemical hotspots that capture and transform carbon and nutrients. Wetland restoration is increasingly used as a climate mitigation strategy because of wetlands' capacity to sequester large amounts of carbon. However, low-salinity tidal marshes exhibit high variability in methane (CH₄) emissions, which could partially offset carbon sequestration under certain conditions. Understanding the drivers of CH₄ variability is crucial for restoration and conservation work. This project uses an observational research approach to assess the relationships between environmental factors and carbon dioxide (CO₂) and CH₄ soil gas fluxes in a restored low-salinity tidal marsh …

Set-Valued Conjugate Calculus And Duality In Optimization And Machine Learning Via Generalized Relative Interiors, Gary Lee Sandine

Dissertations and Theses

Convex analysis, optimization, and duality theory are broadly applicable to a multitude of real-world problems. Theoretical frameworks ensuring strong duality and optimality are fundamentally tied to convex separation under qualification conditions frequently involving topological or relative interiors. These can be empty in convex sets that appear naturally in infinite-dimensional models, yet guarantees of optimality and strong duality are often attainable. This dissertation presents frameworks for applying convex separation via generalized relative interiors to develop generalized calculus rules as well as conditions for strong duality and optimality for infinite-dimensional constrained convex optimization problems.

The first major contribution is the introduction of …

The Influence Of Urban Form On The Distribution Of Air Pollutants, Takin Khosrownia

Dissertations and Theses

Urban form exerts strong control on how pollution from outside a city is transported through the urban canopy and experienced at street level. This study uses the prognostic microclimate model ENVI-met to simulate an active pollutant released from an upwind rural highway and advected through an urban region represented by ten Local Climate Zone (LCZ) types. The cases share identical inflow and are isothermal, dry, and non-vegetated, so that differences among them are attributable to building morphology alone. PM2.5 is the primary exposure diagnostic. Its transport and ejection are characterized through plan-view contours, vertical plume sections, and spatially averaged streamwise …

Experiences Of Psychological Recovery From Work In Second-Generation Asian Americans, Laura Yang

Dissertations and Theses

Individuals of Asian descent make up approximately 7.4% of the U.S. population. As one of the fastest-growing minority groups, their population is projected to reach nearly 15% by 2065, with 38% being foreign-born – surpassing all other racial minority groups. Despite their increasing presence in the U.S. workforce, research on Asian workers' nonwork experiences remains limited. One key unexplored area is how Asian workers engage in recovery after work, considering their unique cultural and racialized experiences. Drawing on literature examining psychological recovery from work, this qualitative study employed multiple methods of analysis, both listening guide method and thematic analysis, to …

Functionality Risk Assessment And Risk-Based Management For Critical Infrastructure Systems, Anteneh Zewdu Deriba

Dissertations and Theses

Critical infrastructure systems such as transportation networks serve as the lifelines of modern society, supporting economic activity and ensuring access to critical services. Their disruption under extreme events can produce consequences extending far beyond physical damage to individual assets. In transportation networks for instance, failures of critical assets such as bridges and tunnels can reduce accessibility of communities, limit freight capabilities for commerce, and increase travel distance and travel time of road users. These consequences associated with the system functionality loss are tied not only to the physical vulnerability and failure of individual assets, but also to the system configuration …

Identity, Needs, And Conflict Online: Understanding Cultural Fragmentation In The Black Diaspora, Imhile Omosede Dora Akpata

Dissertations and Theses

This study examines how identity formation, intra-diaspora tensions, and social media interactions contribute to fragmentation within the Black diaspora. While existing scholarship, including work by Godfried Asante and Elizabeth Chacoko has emphasized the fluid and socially constructed nature of Black identity, less attention has been given to how these processes operate in practice across diverse diasporic groups and how they are intensified in digital environments. This research addresses this gap by analyzing how individuals negotiate Black identity, how tensions emerge within the diaspora, and how social media shapes and amplifies these dynamics.

Drawing on Social Identity Theory developed by Henri …

Improving The Fpga Radio Design Cycle: Implementing Dvb-S2 Modulation Using Verilator And Gnu Radio, Seth Pellegrino

Dissertations and Theses

In embedded digital radio systems, a central challenge is meeting the real-time throughput required to process the samples--especially for space-bound ultra-wideband SDRs which must handle more than 100 Gbps entirely onboard. An FPGA's programmable logic offers sufficient potential, but realizing a particular radio flow is a project usually fraught with defects and long turnaround times. We simulated Verilog modules in a custom harness that adapted a Verilated model to GNU Radio, which allowed for breaking down a complicated radio flow (here, DVB-S2 modulation) into a series of well-bounded problems each with clear criteria for success. The framework, built on open …

Ƒ(Enlightenment): A Complex Adaptive Systems Model Of Recursive Causality And Human Meaning-Making, Daniel Lambert

Dissertations and Theses

Conflict Resolution has developed as a richly interdisciplinary field; however, its theoretical architecture remains fragmented across distinct bodies of scholarship. Existing approaches offer valuable but often isolated explanations of conflict behavior, limiting their ability to account for its complexity. This thesis addresses this limitation by advancing systems science as an organizing framework for integrating these perspectives. It introduces the Human-Complex Adaptive Systems (H-CAS) framework, which conceptualizes human behavior as a recursive adaptive process operating across interconnected regulatory domains. Within this model, conflict is not treated as a discrete event or purely deliberative process, but as an emergent property arising from …

Detecting And Correcting Systematic Image Distortion In Digital Atomic-Resolution Images From Crystals: Projected Symmetry Of Graphite Calibration Samples For Scanning Prove Microscopy And Subperiodic Crystals For Aberration-Corrected Transmission Electron Microscopy, Tyler Michael Bortel

Dissertations and Theses

Though it is an impressive technology, Scanning Tunneling Microscopy (STM) produces images commonly plagued by small systematic errors, often called "drift". These effects have a variety of causes, most notably nonlinear behavior of piezoelectric actuator tubes responsible for the positioning of the scanning probe or sample. One result of these distortions is a potential incorrect classification of the symmetry groups and projected Laue classes of recorded images from crystals—made possible by using recently developed objective methods. An implementation of a known method for detecting and correcting these errors is presented. This method operates strictly in Fourier space so as to …

Intersectional Pathways To Prison And Sentence Disparities: Exploring The Role Of Race, Gender Identity, And Sexuality In Women’S Sentencing Outcomes, Jae Collett

Dissertations and Theses

This study explores the relationship between race, gender identity, sexuality, and prison sentence length using data from the Survey of Prison Inmates, 2016. While state and federal guidelines are ostensibly in place to prevent disparate sentencing outcomes, research still finds disparities in prison sentence lengths across identities of defendants. Women generally receive more lenient sentences than men, and may be shown chivalry when processed through the criminal legal system. However, qualifications for chivalrous treatment have historically only been accessible to certain women (i.e. cisgender, heterosexual, white women). The social and institutional exclusion queer women and/or women of color experience may …

Improved Method Of Evaluating Gas-Phase Air Cleaners Considering Adsorption And Desorption Mechanisms To And From Internal Test Chamber Surfaces, Casey Douglas Coffland

Dissertations and Theses

Portable air cleaners are playing an increasingly important role in managing indoor air quality in response to pressing issues like wildfire smoke events. Smoke is a complex mixture of gases and particulate matter; while established test methods exist for particulate matter, the dynamic behavior of gaseous pollutants is not well accounted for in current test methods. This is because prevailing air cleaner testing methods typically treat background losses as irreversible, whereas gases can engage in partitioning to and from test chamber surfaces. Ignoring these sorption interactions causes inaccurate estimation of an air cleaner's impact.

A new approach has been developed …

Beyond Predation: Invasive Green Crab (Carcinus Maenas) Alters Juvenile Pacific Oyster (Magallana Gigas) Function And Survival Across Environmental Gradients, Isabel Helena Mize

Dissertations and Theses

The establishment of the invasive green crab, Carcinus maenas, creates ecological and economic impacts in estuaries, particularly through predation on bivalves and alteration of species interactions. This thesis evaluates the direct predation, non-consumptive predator presence, and spatial management implications of C. maenas impacts on filtration rate of juvenile Pacific oysters, Magallana gigas, across laboratory, field, and GIS-based vulnerability mapping approaches. In laboratory conditions, clearance rates of M. gigas were measured over 72 hours across two temperatures (14°C and 18°C) and predator treatments including C. maenas, Pacific rock crab (Romaleon antennarium), both predators together, and a …

Flexible Load Communication Protocol Mapping Guide: Ieee 2030.5 To Ansi/Cta-2045, Joseph D'Ambrosia

Dissertations and Theses

As more variable renewable energy resources are connected to the grid, new challenges emerge for grid operators. Demand response programs can provide an additional degree of freedom to grid operators, by modulating the patterns of electricity consumption of residential, customer-owned, flexible loads. The success of demand response programs requires robust and reliable systems of communication between grid operators and flexible loads.

The ANSI/CTA-2045 communication protocol enables customer-owned devices to act as flexible loads. The SEP 2.0/IEEE 2030.5 communication protocol is used to manage distributed energy resources, including flexible loads. Interoperability can be realized by mapping ANSI/CTA-2045 and SEP 2.0/IEEE 2030.5 …

Low Cost Lightning Localization At Microwave Frequencies, Bradley Glaubitz

Dissertations and Theses

High precision lightning localization is essential for atmospheric research and public safety, yet the high cost of traditional VLF/LF systems restricts high resolution detection primarily to well funded agencies. Furthermore, conventional low frequency receivers often overlook microwave frequency emissions associated with lightning leader development. This thesis proposes a compact, low cost microwave frequency localization system operating in the 1.42 GHz band to provide an accessible alternative for high resolution mapping. The methodology utilizes an ARM Cortex M0+ microcontroller and a triggered 64 MHz 32 bit counter synchronized to a GPS Pulse Per Second (PPS) signal, achieving a temporal resolution of …

The Kashmir Conflict After The Abrogation Of Articles 370 And 35a Of The Indian Constitution: Geopolitical Dynamics And Human Security Implications, Rizwan Ali

Dissertations and Theses

The abrogation of Article 370 of the Indian Constitution on August 5, 2019, revoked the special autonomous status of Jammu and Kashmir (J&K) under the Indian administration. It further bifurcated it into two Union Territories under central Indian control. The move came amid a severe security lockdown and communication blackout that lasted for months. It was followed by instrumental legal, social, and economic developments that directly affected the area’s disputed status and the human rights of its residents. This research examines the geopolitical and human security implications of the abrogation and subsequent developments through a qualitative, analytical design, integrating Edward …

Adopting Critical Power Grid Infrastructure Technologies: An Organizational Cybersecurity Assessment Against Ransomware, Fayez Alsoubaie

Dissertations and Theses

For many years, researchers and practitioners have studied emerging technologies in field of energy production and distribution. Power grid systems carry major weights in the energy branch of the economy. Researchers and scientists have been interested in finding ways to connect the power grid gap and improve protection for its technologies.

The research supports organizational adoption and prioritization of critical cybersecurity technologies for ransomware protection in power grid infrastructure. As utilities increasingly integrate digital technologies, they become more vulnerable to sophisticated cyberattacks that can disrupt services and put public safety at risk. The main focus of the study is to …

Assessment Of The Readiness Of Architectural Design Companies To Adopt Eco-Friendly Nanotechnologies In Sustainable Building Design, Ashwaq Essa Al Khalil

Dissertations and Theses

Nanotechnology is emerging as a promising innovation in sustainable architectural design, although its adoption remains slow. Research highlights the advantages of incorporating nanotechnologies in architecture, including improved material performance, enhanced thermal efficiency, reduced energy consumption, improved durability, and progress toward the Sustainable Development Goals (SDGs). These advantages make nanomaterials a promising solution for sustainable building design, particularly in hot-climate regions where energy consumption and carbon emissions associated with conventional building design practices remain major concerns.

Despite this potential, nanotechnology adoption in architecture faces several challenges, including limited real-world applications, slow diffusion in practice, and persistent organizational, economic, and regulatory barriers. …