Digital Commons Network^™

Yang-Baxter Equations, David Lovitz

Dissertations and Theses

Multiple equations in math, physics, quantum information, and elsewhere are referred to as "the" Yang-Baxter equation, in spite of being a broad family of equations. Most of the equations are nonlinear matrix equations, where the unknown variable is a matrix. This is the case for the so called braided, algebraic, and generalized forms of "the" equation, which are the primary focus of this dissertation. Finding solutions to the various forms of these equations has been the subject of much research. The equations in all their forms are largely considered intractable in high dimensions, and only in dimension 2 have the …

Social Reproduction On Campus: Quantitative Investigations Into The Reproduction Of Gender And Socioeconomic Inequality Through Higher Education, Ned William Tilbrook

Dissertations and Theses

This dissertation examines two key axes of inequality in higher education -- gender and socioeconomic status (SES) -- in terms of differences in college persistence and college major using the nationally-representative High School Longitudinal Study of 2009. While gender differences in terms of STEM majors has been oft-studied, this dissertation contributes to this body of literature by advancing Health & Social Sciences (HSS) majors as a separate category and examining the ways in which men and women may be sorted into these different types of major before and during college, despite the strong overlap in science and math related content. …

Leo Strauss On Machiavelli: Athens Vs. Jerusalem Or Ontological Assumptions About Human Nature And Power, Dickson Tiphaine, Jokić Aleksandar

Philosophy Faculty Publications and Presentations

In this article we focus on the true nature of a disparity asserted in Leo Strauss's discussion of Machiavelli to amount to a virtue battle of sorts between Athens and Jerusalem. To convey this conflict Strauss is drawing both on his once Talmudic scholarship and his expertise in the history of political philosophy. We explore the stunning distortions, both theological and philosophical, in Strauss's discussion that appears aimed to support a conservative position on leadership, which calls for the magnanimous few to exercise power over the many (the lowborn, the poor and the vulgar). Not only does Strauss distort the …

Dft Based Modeling Of The Heavy Atom Effect In Triplet Photosensitizers: From Fundamental Mechanics To Rational Design, Bret Andrew Steinkamp

Dissertations and Theses

Photochemistry is the study of how light interacts with molecules and includes both the absorption and release of light. This document focuses on triplet photosensitizers -- molecules that utilize the excited triplet state -- for a variety of applications including photodynamic therapy and photocatalysis. There are many factors that influence the design of triplet photosensitizers; in this work, we have developed and used a methodology for the rational design of triplet photosensitizers based on an approximation of the heavy atom effect (HAE) from density functional theory calculations and the experimentally measured singlet oxygen quantum yield (Ф_Δ).

As excited …

Enhancing Miter Saw Safety: Challenges And Prospects Of Brake Incorporation With An Automatic Blade Retraction System, Derek Cole

University Honors Theses

Miter saws pose significant safety risks with thousands of injuries reported annually. Despite this risk, they are still used every day as they are a necessity for thousands of workers in the United States and globally. This leaves a demand to make these machines safer to mitigate any potential harm. This research addresses the critical need for an automatic safety system for miter saws, aiming to enhance user safety by retracting and stopping the blade upon skin contact. This analysis identified the primary challenge: The large force generated when braking at high speed on a miter saw blade, translates the …

On Coresets For Fair Clustering In Metric And Euclidean Spaces And Their Applications, Sayan Bandyapadhyay, Fedor V. Fomin, Kirill Simonov

Computer Science Faculty Publications and Presentations

Fair clustering is a constrained clustering problem where we need to partition a set of colored points. The fraction of points of each color in every cluster should be more or less equal to the fraction of points of this color in the dataset. The problem was recently introduced by Chierichetti et al. (2017) [1]. We propose a new construction of coresets for fair clustering for Euclidean and general metrics based on random sampling. For the Euclidean space Rd, we provide the first coreset whose size does not depend exponentially on the dimension d. The question of whether such constructions …

Enhancing Robustness Of Machine Learning Models Against Adversarial Attacks, Ronak Guliani

University Honors Theses

Machine learning models are integral for numerous applications, but they remain increasingly vulnerable to adversarial attacks. These attacks involve subtle manipulation of input data to deceive models, presenting a critical threat to their dependability and security. This thesis addresses the need for strengthening these models against such adversarial attacks. Prior research has primarily focused on identifying specific types of adversarial attacks on a limited range of ML algorithms. However, there is a gap in the evaluation of model resilience across algorithms and in the development of effective defense mechanisms. To bridge this gap, this work adopts a two-phase approach. First, …

Moss Biomonitoring Of Lead Emissions From Hillsboro Airport, Daria Kolpakov

University Honors Theses

The objective of this experiment was to use biomonitoring as a method to determine lead concentration levels around Hillsboro Airport in Hillsboro, Oregon. Twenty-two samples were collected within a 2 km radius around Hillsboro Airport using a randomized sampling strategy. The concentrations of lead within the samples were determined using ICP-MS. The average lead concentration was (2.8 ± 5.0) mg/kg with a peak value of 21.6 mg/kg 0.57 km from Hillsboro Airport. As the average lead concentration was substantially skewed, Hillsboro Airport is likely to be the source of the lead increase.

Pt-Symmetry And Eigenmodes, Tamara Gratcheva

University Honors Theses

Spectra of systems with balanced gain and loss, described by Hamiltonians with parity and time-reversal (PT) symmetry is a rich area of research. This work studies by means of numerical techniques, how eigenvalues and eigenfunctions of a Schrodinger operator change as a gain-loss parameter changes. Two cases on a disk with zero boundary conditions are considered. In the first case, within the enclosing disk, we place a parity (P) symmetric configuration of three smaller disks containing gain and loss media, which does not have PT-symmetry. In the second case, we study a PT-symmetric configuration …

The Cultivation Of Ulva Lactuca In Jambiani, Zanzibar: A Case Study, Jazmine R. Compton

Anthós

This case study explores the feasibility of Ulva lactuca cultivation in Jambiani, Zanzibar, Tanzania. The seaweed farming industry in Zanzibar is facing challenges related to climate change that have resulted in increased rates of crop failure and decreased production. Cultivation of the green algae Ulva lactuca has been suggested as a potential solution due to its tolerance to extreme environmental conditions. In collaboration with Marine Cultures, this project has tested different cultivation methods typically used for red algae (Rhodophyta) species. Experimental plots of Ulva lactuca were established in Jambiani, Zanzibar using the floating line and off- bottom methods. At the …

Auditory Ace Mobile Application Capstone Review, Layla Smith

University Honors Theses

This paper describes the development process and outcomes of my 2023-2024 Capstone Project, Auditory Ace, a self-directed auditory training mobile application for individuals with cochlear implants. Recognizing the limitations of current market offerings, Dr. Timothy Anderson created a Capstone project proposal to develop an accessible auditory training mobile application. The Capstone team that took on this proposal consisted of Darya Haines, Dustin Huynh, Jordan Nguyen, Nihar Koppolu, Scott Thorkelson, Sienna Day, and myself, Layla Smith. This paper is structured to follow the Agile software development methodology, which we used to develop Auditory Ace, reviewing in detail every major choice we …

The Cascading Effects Of Database Design, Liam Mccracken

University Honors Theses

This paper details how a relational database influenced the design of the rest of a software project. The software project in question is WonderTix, an open-source ticketing and donation platform for the use of Portland Playhouse under continuous development by teams of Portland State students as their computer science capstone project. The paper, a capstone review thesis, examines WonderTix as an instantiation of the Model-View-Controller design pattern, noting how the model, a relational database based on the SQL standard, influenced the design of the view and controller components. This influence is explored from three angles. First, when the implementation of …

A Case Study In Vacillant Literary Analysis: Nella Larsen's Passing (1929), Sara Casten

University Honors Theses

For the last 95 years, Nella Larsen's Passing has been a topic of discussion within the literary and scholarly communities. First considered Larsen's folly, her second novella Passing had struggled to received a compliment from critics and was quickly lost to readers until her work was rediscovered in the early 1970s. However, unbound by the restrictive literary trope of the era, scholars now wonder if Larsen's Passing had been a misinterpreted masterpiece. This thesis outlines the initial interpretations of critics and modern understanding of scholars in order to highlight the influences of outside influences when reading a written work from …

The Value Of Support: Stem Intervention Programs Impact Student Persistence And Belonging., Erin E. Shortlidge, Mackenzie J. Gray, Suzanne Estes, Emma C. Goodwin

Biology Faculty Publications and Presentations

In response to unwaveringly high attrition from STEM pathways, STEM Intervention Programs (SIPs) support STEM students in effort to increase retention. Using mixed methods (survey and focus groups), we studied students at one university who were either supported or unsupported by SIPs to understand how students may differ in experiences believed to contribute to STEM persistence. We evaluated: sense of belonging, scientific self-efficacy, scientific community values, scientific identity, and STEM involvement. The enrollment status of students two and a half years postsurvey was also tracked. SIP students reported significantly higher science identity and sense of belonging and were more involved …

Matching The Scales Of Planning And Environmental Risk: An Evaluation Of Community Wildfire Protection Plans In The Western Us, Matthew Hamilton, Cody Evers, Max Nielsen-Pincus, Alan A. Ager

Environmental Science and Management Faculty Publications and Presentations

Theory predicts that effective environmental governance requires that the scales of management account for the scales of environmental processes. A good example is community wildfire protection planning. Plan boundaries that are too narrowly defined may miss sources of wildfire risk originating at larger geographic scales whereas boundaries that are too broadly defined dilute resources. Although the concept of scale (mis)matches is widely discussed in literature on risk mitigation as well as environmental governance more generally, rarely has the concept been rigorously quantified. We introduce methods to address this limitation, and we apply our approach to assess scale matching among Community …

An Index Of Biotic Integrity For Macroinvertebrate Stream Bioassessment Conducted By Community Scientists, Patrick M. Edwards, Daniel Bedell, Shannon Hubler, Chad A. Larson, Kate H. Macneale, Elisa Mickelson, Chris Prescott, Elinore Webb, Jo Wilhelm

Environmental Science and Management Faculty Publications and Presentations

Community science bioassessment has great potential to inform comprehensive stream management plans, but regional analytical tools are needed to evaluate macroinvertebrate data collected through community science programs. To this end, we modified a pre-existing professional index of biotic integrity (IBI) to create a community science IBI (CS-IBI), designed for stream macroinvertebrate data collected by community scientists with minimal training. We used data collected by both professional and community scientists to develop, calibrate, and validate the CS-IBI at 76 streamsites in the Puget Lowland andWillamette Valley ecoregions of the PacificNorthwest in theUnited States. Community science data were taxonomically coarser andmore variable …

Virtual Field Environments Capstone Software Review, Ashton Sawyer

University Honors Theses

This is a review of the Virtual Field Environments computer science capstone project, sponsored by geology professor Rick Hugo. The tool aims to create and render VFEs, interactable 360° environments hosted on the web that are used as virtual field trips for K-12 students. This essay discusses the development process, including understanding requirements, tool and technology selection, problem-solving, and decision-making strategies. It also highlights the differences between the capstone and the other core computer science courses, and how those differences help to prepare students for the workforce. The project was completed over the course of twenty weeks by a team …

Development Of A Two-Photon Imaging System, Jesseca Hollenbaugh

University Honors Theses

The objective of this project was to convert a Sarastro 2000 confocal laser scanning microscope (CLSM) into a system capable of far-field two-photon excitation (TPE) imaging for the use of the PSU Biology department. TPE microscopy operates on the ability of fluorophores to accept two photons each with half the energy of a desired transition in a single quantum event via a virtual energy state and then emit a higher energy photon upon relaxation. This is preferable to single-photon excitation (SPE) imaging due to lower photon imaging, causing less damage to delicate biological samples, as well as the inherent localization …

The Pursuit Of Productivity: A Marxist Analysis Of How Frederick Winslow Taylor And Dr. W. Irving Clark Revolutionized The American Factory During The Early Twentieth Century, Stephen Hood

University Honors Theses

In 1911, two events occurred that laid the framework for a revolution in factory management; Frederick Winslow Taylor published his famous work The Principles of Scientific Management; and The Norton Emery Company hired W. Irving Clark to open a first-of-its-kind medical facility. Clark's work should be understood as an extension of the scientific management that Taylor championed during the turn of the twentieth century. The factory served as a laboratory for men like Clark and Taylor to create new methods for increasing productivity while attempting to overcome contradictions inherent to the capitalist mode of production. By utilizing the work …

Lang2views Capstone: The Importance Of A Conscientious Team Lead, Joseph Wornath

University Honors Theses

This review essay reflects the Lang2views capstone project from the perspective of a team lead. The Lang2views capstone project was a web-based user interface designed to simplify how the Lang2views corporation localizes videos into other languages for their clients. Our capstone group was split into three subgroups: front-end, back-end, and DevOps. The strategy for completing the project went through a major change midway through development wherein we changed our software development methodology from a more rigid Waterfall-type approach to a more flexible Agile methodology. Because of this, many of the initially planned features had to be reevaluated as out of …

Remediating History: A Review Of Restoration For Creeks Polluted From Historical Mining Sites, With The Red Boy Mine As A Primary Case Study, Kara Atiyeh

University Honors Theses

I conducted a literature review to examine the key aspects of restoring watersheds affected by pollution from historical mining. This review is then applied to a case study discussion of the Red Boy Mine and Clear Creek remediation project in Granite, Oregon. The goal of this discussion is to explore how an analysis of site conditions along with current literature on management practices can help guide these projects. Thousands of abandoned hard rock mines remain throughout the country, and many pose serious environmental health effects. Heavy metals like cadmium, nickel, and copper are brought to the surface from mining activity, …

Consequences Of Spatial Heterogeneity For Turbulent Wake Development, Ryan Scott

Dissertations and Theses

Spatial heterogeneity is an fundamental property of natural systems. In fluid dynamics subtle variations in fluid motion give rise to chaotic turbulent flows. When a fluid passes an object it retains an imprint of the object as a momentum deficit known as a wake. The resulting spatial structure of the wake is intrinsically linked to the object responsible for its creation. The coupling between geometric complexity in wake producing entities and turbulent wake evolution is considered in terms of spatial heterogeneity from individual wakes through turbulent canopy flows. First a novel Lacunarity-based method is developed for quantifying spatial heterogeneity in …

Efficient And Chemoselective Access To Highly Functionalized Arenes By C-H Deprotonative Generation Of Aryne Intermediates, Bryan Edward Metze

Dissertations and Theses

Arenes are a ubiquitous structural motif occurring in numerous organic pharmaceuticals, agrochemicals, secondary metabolites, and functional materials. As such, studies on the characterization, functionalization, and properties of arenes have been a central pillar of organic chemistry since its inception. Early methods to synthesize complex benzenoid rings focused on ring functionalization rather than ring construction due to the high accessibility of very simple arenes and the wide range of aromatic substitution reactions discovered in the late 19th century. As the importance of arenes was recognized more methods of building complex arenes emerged. Both classical and modern approaches are still somewhat limited, …

Automatic Measurement Of Dialogue Engagingness In Multilingual Settings, Amila Ferron

Dissertations and Theses

Expansive use of large language models (LLMs) as dialogue systems brings increased importance to the evaluation of the responses they generate. Although evaluation of qualities such as coherence and fluency are readily possible with well-established automatic metrics, engagingness is often measured with human evaluation -- a process that can be costly and slows the pace of development. Existing automatic metrics for engagingness have low to moderate correlation with human annotations, evaluate the response without the conversation history, are complicated to implement, or are designed for a specific dataset. Moreover, they have been tested exclusively on English conversations. Given that dialogue …

Towards A New Discourse On Success In Alternative Education, Samuel Thomas Settelmeyer

Dissertations and Theses

Although researchers agree that Alternative Education (AE) within the United States is an essential set of schools and programs that do things beyond traditional education, they do not agree on the purpose for these efforts. To understand how researchers can connect between existing perspectives and consider new ways that they can discuss success in the future, I interviewed 16 students and 15 staff from three different AE schools within the same state. Through thematic analysis, I found students and staff to describe success as an amalgamation of individual and common conceptions, requiring individual effort and support, a commitment to daily …

Experiences Of Community College Stem Students In Transferring And Adapting To A Four-Year Urban University, Mackenzie Jade Gray

Dissertations and Theses

Ensuring that the bachelor's degree pathway that begins at a community college is a robust option for science, technology, engineering, and mathematics (STEM) students will be key for addressing the calls to increase and diversify the future STEM workforce. Yet, students on this pathway currently face many structural barriers that can lead to attrition. In this work, we aim to understand the experiences of community college students as they transfer, adapt, and persist to graduation at an urban four-year university.

First, we used the Model for Analyzing Human Adaptation to Transition to explore the experiences of community college STEM students …

A Systems Theoretic View Of Speculative Realism, Martin Zwick

Complex Systems Faculty Publications and Presentations

Recent developments in Continental philosophy have included the emergence of a school of “speculative realism,” which rejects the human-centered orientation that has long dominated Continental thought. Proponents of speculative realism differ on several issues, but many agree on the need for an object-oriented ontology. Some speculative realists identify realism with materialism, while others accord equal reality to objects that are non-material, even fictional. Several thinkers retain a focus on difference, a well-established theme in Continental thought. This paper looks at speculative realism from the perspective of systems theory. Many of the tenets of speculative realism have long been features of …

Debris Fan Produced By Failure Of Canyon-Blocking Pyroclastic Flows, Michael L. Cummings

Geology Faculty Publications and Presentations

Ash-rich pyroclastic flows from the cataclysmic eruption of Mount Mazama (~7700 yr. B. P.), Cascade volcanic arc, Oregon, entered and blocked the narrow, bedrock-lined canyon of the Williamson River approximately 35 to 44 km from the source volcano. The blockage impounded a body of water which then released producing four stratigraphic units in the downstream debris fan. The four stratigraphic units are a boulder core comprised of locally sourced bedrock boulders and three sand-rich units including a fine-grained sand unit, a sandy pumice gravel (±basalt/hydrovolcanic tuff) unit, and a pumice pebble-bearing, crystal-rich sand unit. Hand-drilled auger holes up to ~1.6 …

Mantle Sources And Geochemical Evolution Of The Picture Gorge Basalt, Columbia River Basalt Group, Emily B. Cahoon, Martin J. Streck, Richard W. Carlson, Ilya N. Bindeman

Geology Faculty Publications and Presentations

The Columbia River Basalt Group (CRBG) is the youngest continental flood basalt province, proposed to be sourced from the deep-seated plume that currently resides underneath Yellowstone National Park. If so, the earliest erupted basalts from this province, such as those in the Picture Gorge Basalt (PGB), aid in understanding and modeling plume impingement and the subsequent evolution of basaltic volcanism. Using geochemical and isotopic data, this study explores potential mantle sources and magma evolution of the PGB. Long known geochemical signatures of the PGB include overall large ion lithophile element (LILE) enrichment and relative depletion of high field strength elements …

A Review Of The Toxicity Of Ingredients In E-Cigarettes, Including Those Ingredients Having The Fda's "Generally Recognized As Safe (Gras)" Regulatory Status For Use In Food., Nada O F Kassem, Robert M. Strongin, Andrea M. Stroup, Marielle C. Brinkman, Ahmad El-Hellani, Hanno C. Erythropel, Arash Etemadi, Vernat Exil, David H. Peyton, Multiple Additional Authors

Chemistry Faculty Publications and Presentations

Some firms and marketers of electronic cigarettes (e-cigarettes; a type of electronic nicotine delivery system (ENDS)) and refill liquids (e-liquids) have made claims about the safety of ingredients used in their products based on the term "GRAS or Generally Recognized As Safe" (GRAS). However, GRAS is a provision within the definition of a food additive under section 201(s) (21 U.S.C. 321(s)) of the U.S. Federal Food Drug and Cosmetic Act (FD&C Act). Food additives and GRAS substances are by the FD&C Act definition intended for use in food, thus safety is based on oral consumption; the term GRAS cannot serve …