Digital Commons Network^™

Public Procurement’S Role In Shaping Supply Markets: A Taxonomy Of Local Contracting Authorities’ Approaches Using The Awareness-Motivation-Capability Framework, Steven Borobia, Frederik G.S. Vos, Louise Knight, Esmee Peters, Fons Wijnhoven, Niels Uenk

Business Faculty Publications and Presentations

Purpose: Public procurement is increasingly recognised as a tool for governing and shaping supply markets. Yet we still know little about how local authorities engage in market shaping through contracting practices, especially in newly decentralized markets. This study investigates the role of awareness, motivation and capabilities (AMC) in how municipalities influence (or fail to influence) social care markets, and how these dynamics manifest in contracting practice. Design/methodology/approach We combine secondary data with semi-structured interviews conducted with procurement professionals across municipalities, regional consortia, and expert organizations. The case context is Dutch social services procurement, which transitioned to a decentralised market in …

Lrq-Solver: A Transformer-Based Neural Operator For Fast And Accurate Solving Of Large-Scale 3d Pdes, Peijian Zeng, Guan Wang, Haohao Gu, Xiaoguang Hu, Tiezhu Gao, Zhuowei Wang, Aimin Yang, Xiaoyu Song

Electrical and Computer Engineering Faculty Publications and Presentations

Solving large-scale PDEs on complex three-dimensional geometries remains a central challenge in scientific and engineering computing, often due to expensive pre-processing stages and high computational overhead. We present Low-Rank Query-based PDE Solver (LRQ-Solver), a physics-integrated deep learning framework for efficient CAE simulations of complex three-dimensional geometries in CAD-driven design analysis. Built upon the Parameter-Conditioned Lagrangian Modeling (PCLM) that embeds physical consistency into the learning process and the Low-Rank Query Attention (LR-QA) module that reduces attention complexity from O(N2) to O(NC2+C3) via covariance decomposition, LRQ-Solver supports multi-configuration analysis within iterative design workflows. On two benchmark datasets, it achieves a 28.6% error …

Factors Influencing Enterprise Adoption Of Ai-Enabled Computers: An Expert Judgment Quantification Approach Across Multiple Sectors, Yu Shan Su, Tugrul Daim, Chia-Hao Hung, Leong Chan, Dana Bakry

Engineering and Technology Management Faculty Publications and Presentations

This study examines the key factors influencing the adoption of Artificial Intelligence Personal Computers (AIPCs) by enterprises, exploring both the benefits and challenges of their business applications. As enterprises increasingly require real-time computing, autonomous decision-making, and improved cybersecurity, AIPC—combining artificial intelligence and edge computing—has become a strategic technology for boosting competitiveness. Particularly in scenarios with less reliance on cloud services, businesses are more likely to adopt devices with local processing and standalone AI capabilities to meet the dual needs of operational efficiency and data privacy. Through an extensive review of the literature, this study identifies four main dimensions and sixteen …

The Vegetated-Canopy Roughness Sublayer Through A Tke-Budget Lens, Giulia Salmaso, Raul Bayoan Cal, Marc Calaf

Mechanical and Materials Engineering Faculty Publications and Presentations

It is well understood that vegetated canopies perturb the atmospheric flow within and immediately above the canopy, deviating from the inertial sublayer (ISL) regime characteristic of non-vegetated rough surfaces. Only above a certain height, denoted as the roughness sublayer height (RSL, 𝑧∗), do these flows return to ISL-like behavior. This distinction is critical, as parameterizations in Earth System Models (ESMs) are typically developed for ISL flows. Yet, most 𝑧∗ estimates stem from studies over flat, homogeneous canopies and may be biased. In contrast, little is known about 𝑧∗ in non-homogeneous or heterogeneous canopies that are not of agricultural interest, with …

Don’T Sweat Interaction Trees Proof-Guided Local Variable Lifting For Interaction Trees, Yiming Lin, Ian Kariniemi, Yao Li

Computer Science Faculty Publications and Presentations

Verifying existing software is hard: Programs are developed in languages not amenable to verification, involve complicated optimizations that obscure the underlying logic, and are gigantic in size. In this paper, we propose a way to ease this pain via a simplification framework that employs interaction trees as a language-agnostic interface. We show that local variable lifting, the technique underlying AutoCorres for the Simpl language, can be generalized to interaction trees via an implementation in Rocq. A key challenge with simplifying interaction trees is that they are highly dynamic structures and we would like our approach to work with mostly uninterpreted …

Superiorgat: Graph Attention Networks For Sparse Lidar Point Cloud Reconstruction In Autonomous Systems, Khalfalla Awedat, Mohamed Abidalrekab, Gurcan Comert, Mustafa Ayad, Negash Begashaw

Electrical and Computer Engineering Faculty Publications and Presentations

LiDAR-based perception in autonomous systems is fundamentally limited by sparse vertical sampling and further degraded by structured beam dropout caused by occlusions, sensor faults, or reduced-cost LiDAR hardware. These degradations disrupt vertical geometric continuity and negatively affect downstream perception tasks such as object detection, localization, and scene understanding. Existing reconstruction approaches often struggle to balance reconstruction accuracy with the computational efficiency required for real-time autonomous operation. This paper presents SuperiorGAT, a graph attention–based framework for reconstructing missing elevation information in sparse LiDAR point clouds under structured beam loss. The proposed method models LiDAR scans as beam-aware graphs and enhances standard …

A Systematic Approach For Controlling Tem Sample Thicknesses, Monte Kozell

Physics Faculty Publications and Presentations

Historically, TEM prep has been an artisan craft without a systematic workflow that ensures quantified control over TEM sample thickness. Over- and under-thinning is a significant problem in the TEM prep process. A direct measurement process was demonstrated to control the final thickness of the TEM lamella. Final lamella thickness was controlled by directly measuring lamella thickness in real time using a 10–15 kV SEM while performing secondary electron imaging at the mill position, allowing for (human-mediated) closed-loop processing. We demonstrated the utility of this technique by systematically thinning five TEM samples to discretely target thicknesses ranging from 100 nm …

Multi-Solution Ternary Grover’S Algorithm For Logic-Based Quantum Machine Learning With Pseudo-Kronecker Reed–Muller Form Minimization, Sophia Lee, Ali Al-Bayaty, Marek Perkowski

Electrical and Computer Engineering Faculty Publications and Presentations

Optimization problems in machine-learning (ML) applications can be computationally challenging for classical methods, particularly when they involve large, unstructured search spaces. Quantum computing offers a promising approach to combinatorial optimization by utilizing quantum superposition and amplitude amplification. This paper presents a new methodology using logic-based quantum machine learning (QML) as a complete framework for employing a multi-solution ternary Grover’s algorithm to minimize incomplete binary functions represented by Pseudo-Kronecker Reed–Muller (PKRO) expansions, consistent with Occam’s razor principle. Unlike previous quantum approaches based on Kronecker Reed–Muller (KRO) or fixed-polarity Reed–Muller (FPRM) representations, our work introduces the first Grover-based optimization framework for PKRO …

Epidemic Dynamics Under Pulse Population Exchange, Hannah Kravitz, Christina Durón, Moysey Brio

Mathematics and Statistics Faculty Publications and Presentations

Many epidemiological models assume either closed populations or continuous demographic turnover. We consider an intermediate setting in which exchange occurs through discrete pulses. In this paper, we introduce a population-conserving compartmental epidemiological model with pulse population exchange at a set of prescribed times. At each pulse, a fraction of the population in each compartment is replaced by a combination of susceptible and immunized individuals. In contrast to typical pulse birth or pulse vaccination models where only a single compartment undergoes a pulse population change, the pulses in this model have competing effects: removing infectious individuals reduces the force of infection, …

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, …

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 …

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 …

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 …

Research Priorities For Robust Climate Assessments In The United States, Melissa A. Kenney, Robert E. Kopp, Constantine Samaras, Marina Alberti, Sonia Y. Angell, Jennifer Burney, Colin Cunliff, Elliott T. Gall, J. T. Duffy-Anderson, Multiple Additional Authors

Mechanical and Materials Engineering Faculty Publications and Presentations

Scientific assessments play a critical role in synthesizing evidence to support evidence-based decision-making in many sectors and topics. For climate change, large-scale assessments like the Intergovernmental Panel on Climate Change (IPCC) and the United States (U.S.) National Climate Assessment (NCA) reports help many different users—from national government to local governments, Indigenous Peoples and communities, the private sector, the social sector, and the scientific community itself—navigate the complex field of climate risks, impacts, and integrated solutions. While co-creation with users is essential to developing actionable assessments, this paper lays the groundwork for future processes by identifying many advancing and emerging areas …

Spatial Reconstructability Analysis: Information-Theoretic Modeling Of Categorical Raster Data, David Percy

Dissertations and Theses

This research focuses on the application of Reconstructability Analysis (RA), an information-theoretic machine learning (ML) methodology, to categorical spatial data in Geographic Information Systems (GIS). RA was developed in the systems community with applications including classification, prediction, pattern recognition, and decision analysis. RA is implemented in OCCAM (Organizational Complexity Computation and Modeling), a software suite developed at Portland State University that analyzes discrete data in tabular form, with observations in rows and variables in columns. While RA has been successfully applied to a variety of domains, no systematic application to georeferenced raster data arranged in regular grids has been previously …

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 …

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 …

“Turn The Faucet”: Right-Wing Hydrosocial Imaginaries Of Irrigation Water In The Western United States, Alexander Reid Ross, Thien-Kim Bui, Alida Cantor

Geography Faculty Publications and Presentations

The second administration of United States President Donald Trump has taken an authoritarian, centralized approach to governance in the United States. Water management is one area in which the president has attempted to show dominance. This research theorizes President Trump’s concept of water in the United States West as a “hydrosocial imaginary” in which the release of water from rivers and reservoirs indicates virility, action, and power, instead of liberal cautiousness and prudence. By ordering the release of two billion gallons of water from California’s Central Valley into the dry Tulare Basin one hundred miles north of Los Angeles for …

We Don't See Race, We See Blue: A Case Study Of Police Unions As Racialized Organizations, Sarahfina Aubrey Peterson

Dissertations and Theses

In the late 1960s, police began to unionize. Today, they are the most well-organized labor force in the United States, with 70% to 80% of sworn officers now represented by a union. Though it has been decades, little scholarship has developed about how police unions affect policing. Much of the research that does exist uses race-neutral frames to address an organization steeped in racial history. This study aims to address this gap in scholarship, in part, by introducing race as a motivation for and explanation of organizational output.

This research applies Victor Ray's racialized organizations theory to police unions. I …

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, …

The Freedom Myth: How Ski Culture's Hidden Conformity Reveals The Unconscious Power Of Brand Belonging, Isabel R. Phillips

University Honors Theses

Purpose: Ski culture sells freedom and enforces conformity. This review asks what unconscious behavioral patterns hold that contradiction in place, and how brands capitalize on it to manufacture belonging.

Design/Methodology/Approach: A narrative literature review across consumer psychology, behavioral neuroscience, sociology, and ski industry research. No primary data were collected. Four accounts of consistency-seeking are synthesized into one framework, then applied to three ski industry cases at ascending scales and tested against a comparative case from Spanish football.

Findings: Belonging is a conditioned response, and conditioning requires a stable stimulus. Consistency is therefore the precondition of belonging rather than a constraint …

Ronald E. Mcnair Research Symposium Presentation Schedule 2026, Mcnair Scholars Program

McNair Symposium

This is the presentation schedule for the 24th Undergraduate Ronald E. McNair Research Symposium 2026.

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 …

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 …

Intrinsic Memory In Digital Snns: Enhancing Performance On The Cart-Pole Task With Fractional-Order Dynamics, Niklas Karl Anderson

Dissertations and Theses

Researchers working with Spiking Neural Networks (SNNs) are faced with the challenge of identifying useful biologically plausible features for inclusion in neuron models. Prior research indicates that dynamics of fractional-order calculus, which impart a form of intrinsic memory, are a key feature of biological neurons. In this work, we present the development and usage of neural networks with intrinsic memory in application to the cart-pole task, a common benchmark for neural network performance. We found that usage of fractional-order neurons may allow for up to a 37.5% reduction in neural network size as compared to networks using a standard Leaky …

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 …

Moss Biomonitoring And Isotopic Signatures Reveal Aviation Fuel As Local Lead Source Near Oregon Airports, Oluwaseyi E. Aderinboye, Alyssa E. Shiel, Lauren Stalford, Christina J. Murphy, Dean B. Atkinson

Chemistry Faculty Publications and Presentations

Lead emissions from piston-engine aircraft using leaded aviation gasoline (avgas) remain a significant source of environmental contamination near regional airports, posing potential health risks to nearby communities. Passive biomonitoring using the epiphytic moss Orthotrichum lyellii was combined with lead isotope fingerprinting to quantify lead concentrations and distinguish between legacy leaded gasoline and current avgas emissions near Hillsboro and Troutdale airports in Oregon. Here we show that lead levels are elevated by up to 50 times the rural background near airports, with isotopic signatures confirming avgas as a dominant local source. These findings indicate that avgas use contributes substantially to environmental …

Prompt Framing And Evidence Requirement For Ai-Generated Educational Responses In Dental Education: Experimental Study., Man Hung, Corban Ward, Owen Cohen, Jacob Marx, Zachary Smit, Jacob Newman, Martin S. Lipsky

Institute on Aging Publications

Large language models are increasingly used in health professions education; however, the role of prompt design in shaping their outputs remains poorly understood in clinical training contexts. In dentistry, where information presentation, perceived credibility, and procedural reasoning are important, the effects of instructional framing and evidence requirements on AI-generated educational responses are particularly relevant.

The Prophylactic Landscape: Sand And Typhoid On The Merrimack River, Laila Seewang

School of Architecture Faculty Publication and Presentations

“The first municipal water filter of the rapid sand type was built at Somerville, NJ, and thus began its wonderful history.”  By 1917 the rapid sand filter was the standard defense against typhoid epidemics in the United States.