Digital Commons Network^™

The Foodpunk City: Advancing Portland's Food Security Through A Shared Ideology Of Adaptation & Resistance, Nickolas Hash

Dissertations and Theses

Food injustice is a form of violence perpetrated by state and corporate actors against a constituency under their governing power, particularly impacting marginalized and impoverished communities. It denies individuals access to nutritious food, perpetuating cycles of poverty, inequality, physical health risks, and social exclusion. Grassroots movements have emerged to challenge dominant paradigms and advocate for food sovereignty, agroecology, and food anarchy. In Portland, the movement represents a nontraditional approach to food security that closely resembles the reactionary ideology of urban "punk" culture. Both groups prioritize community autonomy over food systems, sustainable agricultural practices, and resistance to oppressive structures that perpetuate …

Introduction To The Virtual Special Issue: Mathematics That Underpins Social Issues, Eva Thanheiser, Ami Mamolo

Mathematics and Statistics Faculty Publications and Presentations

This Virtual Special Issue on Mathematics in Society: Exploring the Mathematics that Underpins Social Issues features 13 articles which expand our understanding of how people build, retain, communicate, apply, and comprehend mathematical ideas as they relate to social and societal issues. The focus is on education research that explores the ways in which mathematics and a mathematical worldview can influence choices, on educational, personal and societal levels. We take a broad view and raise questions about what it means to be mathematical in society, and we consider the multifaceted ways in which abilities to derive and interpret information presented mathematically …

Evaluation Of Transplant Benefits With The Us Scientific Registry Of Transplant Recipients By Semiparametric Regression Of Mean Residual Life, Ge Zhao, Yanyuan Ma, Huazhen Lin, Yi Li

Mathematics and Statistics Faculty Publications and Presentations

Kidney transplantation is the most effective renal replacement therapy for end stage renal disease patients. With the severe shortage of kidney supplies and for the clinical effectiveness of transplantation, patient’s life expectancy posttransplantation is used to prioritize patients for transplantation; however, severe comorbidity conditions and old age are the most dominant factors that negatively impact posttransplantation life expectancy, effectively precluding sick or old patients from receiving transplants. It would be crucial to design objective measures to quantify the transplantation benefit by comparing the mean residual life with and without a transplant, after adjusting for comorbidity and demographic conditions. To address …

2024 Summer Proceedings Teuscher Lab, Teuscher Group, Christof Teuscher, Chelsea Ogbede, Lauren Sanday, Sofia Vargas, Artem Arefev

altREU Projects

How will computation evolve in the coming years? What problems can be tackled using artificial intelligence, in a world increasingly driven by data? And how can that data be used to better inform our decisions as a society? In this unique collection of research projects, each chapter represents a distinct work undertaken by a single individual or a group of students as part of the altREU program led by Christof Teuscher. The projects, rooted in applications of artificial intelligence and innovative computation techniques, examine impactful solutions to numerous pressing challenges affecting communities around the world.

Beyond Environmental Harm: Industry Claims, Lived Experiences, And The Impacts Of Gas Extraction, Martina Angela Caretta, Melissa Haeffner, Ryan Emanuel, Racheal Hood, Julia Seydel

Environmental Science and Management Faculty Publications and Presentations

The peer-reviewed literature presents overwhelming evidence that fossil fuel based energy infrastructure projects are responsible for lower residential property values, environmental destruction and pollution that decrease residents' quality of life. These projects also challenge local people's sense of identity and even the threat of such a project can make residents question their sense of place. As evidence, we first present a bibliographic analysis of the environmental impact statements for the Mountain Valley Pipeline in West Virginia and the Jordan Cove Energy Project in Oregon. We find that their approval processes relies on non-peer-reviewed, industry-funded claims that pipelines will bring economic …

Regiongrow3d: A Deterministic Analysis For Characterizing Discrete Three-Dimensional Landslide Source Areas On A Regional Scale, Nicolas W. Mathews, Ben A. Leshchinsky, Benjamin B. Mirus, Michael J. Olsen, Adam M. Booth

Geology Faculty Publications and Presentations

Regional-scale characterization of shallow landslide hazards is important for reducing their destructive impact on society. These hazards are commonly characterized by (a) their location and likelihood using susceptibility maps, (b) landslide size and frequency using geomorphic scaling laws, and (c) the magnitude of disturbance required to cause landslides using initiation thresholds. Typically, this is accomplished through the use of inventories documenting the locations and triggering conditions of previous landslides. In the absence of comprehensive landslide inventories, physics-based slope stability models can be used to estimate landslide initiation potential and provide plausible distributions of landslide characteristics for a range of environmental …

Machine Learning Framework For Predicting Reliability Of Solder Joints, Robert Lee Jones

Dissertations and Theses

This paper presents the techniques and framework to produce an explainable machine learning model for predicting the reliability of solder joints exposed to thermal cycle testing. While machine learning techniques have become prevalent for many engineering and data analysis tasks, the complexity of the model occludes valuable information which can be used to refine the data, tune model parameters, and aid in scientific discovery. By exposing the relationships within the model, users can have greater confidence in the use and employment of it. The purpose of this study is to show how useful relationships can be obtained from a traditional …

Application Of Participatory Process Mapping To Evaluate Environmental Decision-Making And Implementation, Karissa Courtney, Emily Rabung, Jennifer Brousseau, Antony S. Cheng, A. Paige Fischer, Harrison Fried, Matthew Hamilton, Federico Holm, Jordan Inskeep, Max Nielsen-Pincus, Multiple Additional Authors

Environmental Science and Management Faculty Publications and Presentations

Environmental governance outcomes hinge on the design and implementation of management decisions. Yet, available research methodologies can be limited in their ability to capture the complexity of decision-making and implementation processes and in turn predict and explain environmental governance outcomes. We present participatory process mapping as a method for examining the pathways that emerge and evolve over time that result in natural resource management decisions and on-the-ground outcomes, as perceived by participants in collaborative processes. The approach leverages a large-N comparative design, participatory diagraming within semi-structured interviews, and mental modeling toward a method that can fit into both quantitative and …

Matrix-Free High-Performance Saddle-Point Solvers For High-Order Problems In H (Div), Will Pazner, Tzanio Kolev, Panayot S. Vassilevski

Mathematics and Statistics Faculty Publications and Presentations

This work describes the development of matrix-free GPU-accelerated solvers for high-order finite element problems in . The solvers are applicable to grad-div and Darcy problems in saddle-point formulation, and have applications in radiation diffusion and porous media flow problems, among others. Using the interpolation–histopolation basis (cf. [W. Pazner, T. Kolev, and C. R. Dohrmann, SIAM J. Sci. Comput., 45 (2023), pp. A675–A702]), efficient matrix-free preconditioners can be constructed for the -block and Schur complement of the block system. With these approximations, block-preconditioned MINRES converges in a number of iterations that is independent of the mesh size and polynomial degree. The …

A Configurable Real-Time Event Detection Framework For Power Systems Using Swarm Intelligence Optimization, Umar Farooq, Midrar Adham, Mohammed Alsaid, Robert B. Bass

Electrical and Computer Engineering Faculty Publications and Presentations

Power system balancing authorities are routinely affected by sudden frequency fluctuations. These frequency events can take the form of negligible frequency deviations or more severe emergencies that can precipitate cascading outages, depending on the severity of the disturbance and efficacy of remedial action schema. It is imperative to arrest such disturbances quickly by activating primary frequency control measures. This manuscript proposes a configurable event detection framework using optimization methods to tune a detection algorithm to detect events as specified by experts from a Balancing Authority. The utility of the detection framework is demonstrated using a regression-based frequency event detection algorithm …

The Basic Dualism In The World: Object-Oriented Ontology And Systems Theory, Martin Zwick

Complex Systems Faculty Publications and Presentations

Graham Harman writes that the “basic dualism in the world lies…between things in their intimate reality and things as confronted by other things.” However, dualism implies irreconcilable difference; what Harman points to is better expressed as a dyad, where the two components imply one another and interact. This article shows that systems theory has long asserted the fundamental character of Harman’s dyad, expressing it as the union of internal structure and external function, which correspond exactly to what Levi Bryant, characterizing Harman’s views, refers to as the intra-ontic and the inter-ontic, respectively. After interpreting Harman’s dyad in terms of the …

Ronald E. Mcnair Scholars Program Profiles And Abstracts 2024, Mcnair Scholars Program

McNair Symposium

This is the complete event program and provides presentation abstracts and biographies of McNair scholars and their mentors.

A Pwm Control Method For Reducing Electromagnetic Noise At The Generation Source In Power Electronic Converters, Abhijeet Prem

Dissertations and Theses

Advancements in power semiconductor devices are enabling the design of better electrical power conversion systems. Wide Bandgap (WBG) switching devices using materials like Silicon Carbide and Gallium Nitride can operate at higher temperatures, voltages, and frequencies with faster turn-on/off periods, improving converter performance over silicon devices. However, WBG technologies are still new, and the rapid switching transitions of these devices lead to issues such as voltage overshoots, ringing, and electromagnetic interference, which need to be addressed for widespread adoption. This work introduces a new control method for reshaping the switching voltages, which overcomes the disadvantages of fast transition time without …

Agnotology Of The E-Cigarette Industry: How The E-Cigarette Industry Continues The Tobacco Industry's Legacy Of Creating Controversy And Confusion Within The Scientific Community And The General Population, Calvin Lewis

University Honors Theses

The purpose of this paper is to determine the extent to which the e-cigarette industry follows in the footsteps of the tobacco industry's attempts to disrupt science and cause controversy. Four tactics are described that the tobacco industry uses to disrupt science: funding research that is designed to show results that support their position, criticizing and suppressing research that goes against their position, changing risk assessment and scientific research standards to fit their aims, and spreading data created by their interest groups to politicians and the nonacademic press. Evidence is found to show that both the tobacco industry and e-cigarette …

Sustainability In The Specialty Mushroom Industry And The Fight Against Single-Use Plastic: A Case Study, Amanda Newman

University Honors Theses

Specialty mushroom cultivator, Bridgetown Mushrooms, generates approximately 3 metric tons of polypropylene plastic waste a year. This is just a fraction of the 1-2 million metric tons created by the specialty mushroom industry annually. With only 10% of plastic waste being used as secondary materials, the majority of this waste ends up in landfills or in the environment. Through collaboration with employees within Bridgetown’s operation and government agency mentorship, it was determined that the most viable and ecological solution to reduce on-farm plastic waste within Bridgetown’s operation was to develop a reusable growing apparatus as a direct replacement for polypropylene …

Story Of Your Lazy Function's Life: A Bidirectional Demand Semantics For Mechanized Cost Analysis Of Lazy Programs, Li-Yao Xia, Laura Israel, Maite Kramarz, Nicholas Coltharp, Koen Claessen, Stephanie Weirich, Yao Li

Computer Science Faculty Publications and Presentations

Lazy evaluation is a powerful tool that enables better compositionality and potentially better performance in functional programming, but it is challenging to analyze its computation cost. Existing works either require manually annotating sharing, or rely on separation logic to reason about heaps of mutable cells. In this paper, we propose a bidirectional demand semantics that allows for extrinsic reasoning about the computation cost of lazy programs without relying on special program logics. To show the effectiveness of our approach, we apply the demand semantics to a variety of case studies including insertion sort, selection sort, Okasaki's banker's queue, and the …

Quantifying Relationships In Fuzzy Cognitive Maps Based On Content Analysis Of Unstructured Research Texts, Ahmed Alibage, Antonie J. Jetter, Elpiniki Papageorgiou

Engineering and Technology Management Faculty Publications and Presentations

FCM projects often rely on knowledge-based approaches, such as expert interviews, which can be challenging to conduct because they require extensive expert participation. We propose a novel alternative to create FCM models based on expert knowledge that is already codified in research texts and other publications. In this approach, thematic network analysis identifies FCM concepts and signed causal connections, while computation of t-coefficient is used to determine the weights of the identified edges. We introduce and evaluate the approach in the context of a real-world system modeling project that is based on 47 carefully selected, peer reviewed research publications on …

Mental Models Of Translational Scientists, Rasnia Tabpla, Antonie J. Jetter

Engineering and Technology Management Faculty Publications and Presentations

Translational science aims to bridge the gap between scientific discoveries and practical application yet faces challenges in achieving high success rates. This study examines the effective engagement of translational scientists, who play a key role in the translation process. It uses Fuzzy Cognitive Maps (FCMs) to analyze the scientists' mental models and identify common concepts related to success factors, such as ability, resources, opportunity, and entrepreneurial competencies. It then compares the mental models of the scientists and finds that mental models exhibit similarities, yet variations exist such as density and connectedness. Scenario analysis with FCM is then used to identify …

Accretion Of Warm Chondrules In Weakly Metamorphosed Ordinary Chondrites And Their Subsequent Reprocessing, Alex M. Ruzicka, Richard C. Hugo, Jon M. Friedrich, Michael T. Ream

Geology Faculty Publications and Presentations

To better understand chondrite accretion and subsequent processes, the textures, crystallography, deformation, and compositions of some chondrite constituents in ten lithologies of different cluster texture strength were studied in seven weakly metamorphosed (Type 3) and variably shocked ordinary chondrites (Ragland—LL3 S1, Tieschitz—H/L3 S1, NWA 5421—LL3 S2, NWA 5205—LL3 S2, NWA 11905—LL3-5 S3, NWA 5781—LL3 S3, NWA 11351—LL3-6 S4) using optical and electron microscopy and microtomography techniques.

Results support a four-stage model for chondrite formation. This includes 1) limited annealing following collisions during chondrule crystallization and rapid cooling in space prior to accretion, as evidenced by olivine microstructures consistent with dislocation …

Hierarchy Of Exchange-Correlation Functionals In Computing Lattice Thermal Conductivities Of Rocksalt And Zinc-Blende Semiconductors, Jiacheng Wei, Zhonghao Xia, Yi Xia, Jiangang He

Mechanical and Materials Engineering Faculty Publications and Presentations

Lattice thermal conductivity (𝜅L) is a crucial characteristic of crystalline solids with significant implications for thermal management, energy conversion, and thermal barrier coating. The advancement of computational tools based on density functional theory (DFT) has enabled the effective utilization of phonon quasiparticle-based approaches to unravel the underlying physics of various crystalline systems. While the higher order of anharmonicity is commonly used for explaining extraordinary heat transfer behaviors in crystals, the impact of exchange-correlation (XC) functionals in DFT on describing anharmonicity has been largely overlooked. The XC functional is essential for determining the accuracy of DFT in describing interactions among electrons/ions …

Itagaki Paru's Animalized Japan, Adoria Shanelle Walker

Dissertations and Theses

In the earlier works of manga artist and author Itagaki Paru, animal characters are used to prompt a discussion of the uchi/soto ("in-group"/"out-group") dynamic present in Japanese society. Throughout her most popular work, Beastars, and its supplemental short story collection Beast Complex, Itagaki tackles binary thinking and in-group versus out-group social politics using a blatantly obvious, yet nuanced and subtle herbivore-versus-carnivore, predator-versus-prey metaphor. The world she depicts in these works is full of misunderstandings caused by hastily made assumptions, sometimes instinctually quick. With her animalized characters, she explores human stigmatization and the poor treatment of those who do not want …

Examining Driver Injury Severity In Motor Vehicle Crashes: A Copula-Based Approach Considering Temporal Heterogeneity In A Developing Country Context, Shahrior Pervaz, Tanmoy Bhowmik, Naveen Eluru

Civil and Environmental Engineering Faculty Publications and Presentations

Using data from a developing country, the current study develops a copula-based joint modeling framework to study crash type and driver injury severity as two dimensions of the severity process. To be specific, a copula-based multinomial logit model (for crash type) and generalized ordered logit model (for driver severity) is estimated in the study. The data for our analysis is drawn from Bangladesh for the years of 2000 to 2015. Given the presence of multiple years of data, we develop a novel spline variable generation approach that facilitates easy testing of variation in parameters across time in crash type and …

Toxicity Of Waterpipe Tobacco Smoking: The Role Of Flavors, Sweeteners, Humectants, And Charcoal, Nada O F Kassem, Robert M. Strongin, Andrea M. Stroup, Marielle C. Brinkman, Ahmad El-Hellani, Hanno C. Erythropel, Arash Etemadi, Maciej L. Goniewicz, Eleanore G. Hansen, Noura O. Kassem, Multiple Additional Authors

Chemistry Faculty Publications and Presentations

Waterpipe tobacco (WPT) smoking is a public health concern, particularly among youth and young adults. The global spread of WPT use has surged since the introduction of pre-packaged flavored and sweetened WPT, which is widely marketed as a safer tobacco alternative. Besides flavorants and sugars, WPT additives include humectants, which enhance the moisture and sweetness of WPT, act as solvents for flavors, and impart smoothness to the smoke, thus increasing appeal to users. In the United States (U.S.), unlike cigarette tobacco flavoring (with the exception of menthol), there is no FDA product standard or policy in place prohibiting sales of …

Synthesis And Computational Studies Of Α- And Δ-Substituted Macrocyclic Europium And Ytterbium Complexes, Delainey Amara Winder

Dissertations and Theses

The uses of macrocyclic lanthanide complexes are vast, with many targeted MRI contrast agents at the forefront of the field. Many of these are ParaCEST agents, which require exchangeable protons accessible on the macrocycle and the slow exchange of coordinated water molecules. The substitution at both the α- and δ-carbon on the amide pendant arm of these macrocyclic lanthanide complexes can lock bulky groups on the δ-carbon to a pseudo-axial position. When the α- and δ-carbons have the same chirality, the bulky group will be pseudo-equatorial, and when the chirality is opposed, the bulky group will be pseudo-axial. By performing …

Crown Shy, Laura Francesca Kincaid

Dissertations and Theses

Crown Shy explores the ripple effects of inheritance--somatic, psychological, and material--and how such inheritance constellates into our adult relations and relating. In three parts, the text undermines nuclear family imaginings, first by pulling them out by the root, and later through radical practice, formal constraint, and syntactic ambiguity. By studying the natural world--the organizing principles of trees, insects, and flowers--Crown Shy attempts to glean strategy from evidence of what is already thriving. Reluctantly lyrical, the text quietly deplores the ramifications of commercial agriculture, including the speaker’s own family farm and ancestral homestead. With the weight of this origin point, …

Framework And Methodology For Risk-Based Bridge And Tunnel Asset Management: Objective Risk Assessment And Network Level Evaluation, David Y. Yang, Arash Khosravifar, Diane Moug, Avinash Unnikrishnan

Civil and Environmental Engineering Faculty Publications and Presentations

This report presents the results of the project on establishing a general framework and methodology for risk-based bridge and tunnel asset management. The research was carried out at Portland State University in collaboration with engineers and officials at Oregon Department of Transportation (ODOT) and Federal Highway Administration (FHWA). The primary goal of the research is to achieve risk-based transportation asset management based on (a) objective and consistent risk assessment and (b) effective prioritization and optimization of intervention strategies. Volume I of this report presents methods and findings in the base phase (Phase I) of the project, which is focused on …

Oregon State Rank Assessment For Midget Quillwort (Isoetes Minima), Lindsey K. Wise

Institute for Natural Resources Publications

Oregon state conservation status assessment for midget quillwort (Isoetes minima) using NatureServe methodology, 2024.

When Overextended Surface Allocation Turns To Groundwater: A Q Methodology Of Well Users In Oregon’S High Desert, Melissa Haeffner, Janet Cowal, Brandy Walker, Clare Mcclellan

Environmental Science and Management Faculty Publications and Presentations

As legal battles over surface water allocation in Klamath County, Oregon, USA have gained national attention, earning the name “Water Wars,” authorities have been increasingly turning to groundwater to compensate for water shortfalls. This case study aims to identify the nuanced perspectives of household groundwater well users who are affected by groundwater extraction. Using Q methodology, we uncover groundwater well users’ perceptions and to what extent they think water problems are dealt with fairly. We identify four water perspectives that differ in the degree to which respondents prioritize clean water accessibility, industry accountability, individual responsibility for water management, and trust …

Fem-Based Conductive Heat Transfer Analytical Description Of Solidification Rate And Temperature Gradient During Lateral Laser Beam Oscillation Welding Of Aluminum Alloy, Jason Cheon, Cheolhee Kim, Sanghoon Kang, Minjung Kang

Mechanical and Materials Engineering Faculty Publications and Presentations

This study investigates the feasibility of utilizing the finite element method (FEM)-based conductive heat transfer (CHT) analysis simulation to determine temperature gradients and solidification rates at the solid–liquid interface during laser beam oscillation welding. By comparing experimental observations with FEM-based CHT analysis, the underlying microstructural evolution and grain formation during welding were examined. FEM-based CHT enables the calculation of temperature gradients (G) and solidification rates (R), offering insights into the formation of equiaxed structures, which are crucial for suppressing hot cracking. Columnar-to-equiaxed structure transition thresholds, such as G/R and G³/R, accurately predict …

Synoptic Drivers Of Extreme Precipitation In The Upper Yuba Watershed Of California, Emma Nichole Russell

Dissertations and Theses

The United States state of California is vulnerable to both droughts and extreme precipitation events due to the timing and processes of precipitation in the region. California's annual precipitation is dependent on a few strong storms and in addition to its Mediterranean climate, leads to great variability in precipitation both within and across years. While efforts to reduce the impacts of extreme precipitation events have been implemented, forecasting for these events remains a challenge in regions with complex terrain and dynamic meteorological drivers. In order to improve forecasting and preparedness for such events, it is important to understand the range …