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2024

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Full-Text Articles in Physical Sciences and Mathematics

The Mongolian Remodeling And The Structure Of Anoplocephalid Cestode Diversity, Mackenzie Grover Dec 2024

The Mongolian Remodeling And The Structure Of Anoplocephalid Cestode Diversity, Mackenzie Grover

All NMU Master's Theses

Ecological disruption plays an important role in structuring diversity of flora, fauna, and their parasites. At the end of the Eocene, climatic change across Asia resulted in a faunal turnover (the Mongolian Remodeling) as rodents diversified and larger mammals declined. Throughout the Oligocene, the landscape in Asia was characterized by episodic climatic and landscape changes resulting in pulses of rodent diversification. The role of historical ecological disruption in Central Asia in structuring the diversity of parasites of small rodents has not been thoroughly investigated. The hyper-diverse Paranoplocephala species complex (family: Anoplocephalidae) infect rodents throughout the Holarctic and present an opportunity …


Hitch Cart “Landing Gear”, Rebekah White, Jose Raygoza, Randy Hernandez, Brandon Leon Dec 2024

Hitch Cart “Landing Gear”, Rebekah White, Jose Raygoza, Randy Hernandez, Brandon Leon

Mechanical Engineering

This report aims to allow our sponsor, to review our design process of the Hitch Cart Landing Gear Prototype. In the design overview section of this report, we discuss the primary design modifications we made to the wheel mechanism of the existing hitch cart prototype, including the addition of the ACME screws and the folding brackets. This allows our sponsor to see the intended improvements made to the past prototype and understand the primary goal of our project. Then, in the implementation section, we cover the entire manufacturing process to allow our sponsor to understand what manufacturing steps must be …


Limit Theorems For L-Functions In Analytic Number Theory, Asher Roberts Sep 2024

Limit Theorems For L-Functions In Analytic Number Theory, Asher Roberts

Dissertations, Theses, and Capstone Projects

We use the method of Radziwill and Soundararajan to prove Selberg’s central limit theorem for the real part of the logarithm of the Riemann zeta function on the critical line in the multivariate case. This gives an alternate proof of a result of Bourgade. An upshot of the method is to determine a rate of convergence in the sense of the Dudley distance. This is the same rate Selberg claims using the Kolmogorov distance. We also achieve the same rate of convergence in the case of Dirichlet L-functions. Assuming the Riemann hypothesis, we improve the rate of convergence by using …


Reclaiming Healing Spaces: A Phenomenological Study On The Transformative Power Of Outdoor Therapy From The Lived Experiences Of Black Clinicians Working With Black Clients, Lynn Murphy Sep 2024

Reclaiming Healing Spaces: A Phenomenological Study On The Transformative Power Of Outdoor Therapy From The Lived Experiences Of Black Clinicians Working With Black Clients, Lynn Murphy

Dissertations

This phenomenological study involved assessing the experiences of Black therapists who engaged Black clients in outdoor therapeutic contexts. The study was founded on the existing literature that shows the quality of the therapeutic relationship is pivotal for client retention and the Western standards that have historically favored treatment within indoor environments. To contextualize this research, a comprehensive literature review was commenced, covering topics such as the decolonization of therapy, the historical and present-day relationship between Blacks and the outdoors in the United States, sedentary lifestyles, the psychological benefits of time spent in nature, various types of outdoor therapy, and the …


On Weak Solutions And The Navier-Stokes Equations, Aryan Prabhudesai Aug 2024

On Weak Solutions And The Navier-Stokes Equations, Aryan Prabhudesai

Mathematical Sciences Undergraduate Honors Theses

In this paper, I will discuss a partial differential equation that has solutions that are discontinuous. This example motivates the need for distribution theory, which will provide an interpretation of what it means for a discontinuous function to be a “solution” to a PDE. Then I will give a detailed foundation of distributions, including the definition of the derivative of a distribution. Then I will introduce and give background on the Navier-Stokes equations. Following that, I will explain the Millennium Problem concerning global regularity for the Navier-Stokes equations and share mathematical results regarding weak solutions. Finally, I will go over …


Enabling Iov Communication Through Secure Decentralized Clustering Using Federated Deep Reinforcement Learning, Chandler Scott Aug 2024

Enabling Iov Communication Through Secure Decentralized Clustering Using Federated Deep Reinforcement Learning, Chandler Scott

Electronic Theses and Dissertations

The Internet of Vehicles (IoV) holds immense potential for revolutionizing transporta- tion systems by facilitating seamless vehicle-to-vehicle and vehicle-to-infrastructure communication. However, challenges such as congestion, pollution, and security per- sist, particularly in rural areas with limited infrastructure. Existing centralized solu- tions are impractical in such environments due to latency and privacy concerns. To address these challenges, we propose a decentralized clustering algorithm enhanced with Federated Deep Reinforcement Learning (FDRL). Our approach enables low- latency communication, competitive packet delivery ratios, and cluster stability while preserving data privacy. Additionally, we introduce a trust-based security framework for IoV environments, integrating a central authority …


Application Of Functionalized Organosilicas In Adsorption Of Nitrates, Stephen Amoako Aug 2024

Application Of Functionalized Organosilicas In Adsorption Of Nitrates, Stephen Amoako

Electronic Theses and Dissertations

This study addresses the critical environmental issue of elevated nitrate levels in water bodies, primarily due to excessive use of nitrogenous fertilizers and improper waste disposal. It focuses on reducing nitrate concentrations in polluted water to permissible levels through the effectiveness of hybrid materials in nitrate adsorption. We synthesized nine amino-functionalized adsorbents using grafting and sol-gel techniques. Batch adsorption tests confirmed the high nitrate adsorption capacities of these adsorbents, with sol-gel materials showing the highest efficiency due to their abundant amino group contents. Among these, the surfactant-free, sol-gel adsorbent was the most effective, combining ease of synthesis with cost-efficiency. Our …


An Application Of An In-Depth Advanced Statistical Analysis In Exploring The Dynamics Of Depression, Sleep Deprivation, And Self-Esteem, Muslihat Gaffari Aug 2024

An Application Of An In-Depth Advanced Statistical Analysis In Exploring The Dynamics Of Depression, Sleep Deprivation, And Self-Esteem, Muslihat Gaffari

Electronic Theses and Dissertations

Depression, intertwined with sleep deprivation and self-esteem, presents a significant challenge to mental health worldwide. The research shown in this paper employs advanced statistical methodologies to unravel the complex interactions among these factors. Through log-linear homogeneous association, multinomial logistic regression, and generalized linear models, the study scrutinizes large datasets to uncover nuanced patterns and relationships. By elucidating how depression, sleep disturbances, and self-esteem intersect, the research aims to deepen understanding of mental health phenomena. The study clarifies the relationship between these variables and explores reasons for prioritizing depression research. It evaluates how statistical models, such as log-linear, multinomial logistic regression, …


Implementing General Moment Equations For Parallel Closures In Nimrod, Hankyu Lee Aug 2024

Implementing General Moment Equations For Parallel Closures In Nimrod, Hankyu Lee

All Graduate Theses and Dissertations, Fall 2023 to Present

Understanding how magnetic fields impact plasma transport is essential for improving the efficiency of thermonuclear fusion power plants. To address the transport problem, both plasma fluid equations and Maxwell’s equations must be solved. To solve these equations, it is necessary to derive closure relations that allow the system to be closed. Previous closure models are useful for describing the behavior of high-collisionality plasma but are not effective at low collisionality. To obtain closure relations valid for low collisionality, the first-order drift kinetic equation must be solved.

This study presents methods for numerically obtaining parallel closures for NIMROD code by deriving …


Creating A Virtual Hierarchy From A Relational Database, Yucong Mo Aug 2024

Creating A Virtual Hierarchy From A Relational Database, Yucong Mo

All Graduate Theses and Dissertations, Fall 2023 to Present

In data management and modeling, the value of the hierarchical model is that it does not require expensive JOIN operations at runtime; once the hierarchy is built, the relationships among data are embedded in the tree-like hierarchical structure, and thus querying data could be much faster than using a relational database. Today most data is stored in relational databases, but if the data were stored in hierarchies, what would these hierarchies look like? And more importantly, would this transition lead to a more efficient database? This thesis explores these questions by introducing a set of algorithms to convert a relational …


The Gavel And The Camera: Environmental Law And Photojournalism's Relationship To Appalachian Identity, Emily S. Patton Aug 2024

The Gavel And The Camera: Environmental Law And Photojournalism's Relationship To Appalachian Identity, Emily S. Patton

Honors Theses

Both the federal government and photojournalism have played a substantial role in the “othering” of Appalachia while simultaneously attempting to save it. Examining both institutions demonstrates the exploitative processes that alter the perception of rural communities and their surrounding environment. Stacey Kranitz’s archival exhibit, As It Was Give(n) To Me, internalizes this precarious role of the camera in a region heavily journalized. By inhabiting the area for years, establishing close relationships, and researching the documented history of Appalachia, Kranitz’s work becomes her livelihood in the dissolution of profession vs. personal. She is critical of past projects whose objective portrayal of …


Developing Educational Tools For Sustainable Stormwater Management, Lauren Houskeeper Aug 2024

Developing Educational Tools For Sustainable Stormwater Management, Lauren Houskeeper

All Graduate Reports and Creative Projects, Fall 2023 to Present

Rapid population growth and development in Western states are exerting strain on the region’s limited water resources. Urbanization exacerbates this issue by increasing impervious surfaces, limiting infiltration of precipitation during storm events and snowmelt, which results in changes to hydrologic conditions with higher runoff volumes and higher peak flows. Stormwater transports pollutants as it flows across impervious surfaces, discharging high volumes of runoff and elevated loads of urban contaminants into receiving waters. The amount of pollution entering waterways continually increases as urban areas expand. Utah is currently experiencing a rapid transition from undeveloped to developed landscapes, necessitating the implementation of …


Excited State Processes In Radical Elaborated Platinum Donor-Acceptor Complexes, Sangita Paudel Jul 2024

Excited State Processes In Radical Elaborated Platinum Donor-Acceptor Complexes, Sangita Paudel

Chemistry and Chemical Biology ETDs

Organo-transition metal complexes are being widely studied to understand their photophysical properties for their wide range of applications as efficient emitters in organic light emitting diodes (OLEDs), light emitting electrochemical cells (LEECs), etc. Cyclometalated organo-transition metal complexes such as cyclometalated square planar platinum(II) complexes are becoming suitable candidates for such applications because of their highly efficient luminescence. Understanding the excited properties of such complexes is useful in designing highly efficient and color tunable phosphors with desired excited state lifetimes. We aim to explore the influence of radical substituents on electronic structure, luminescence quantum efficiencies, and excited state lifetimes by synthesizing …


Examining The Interaction Between Calcium Supplement Use, Demographics, And Lifestyle Factors On Bone Health Of Women, Vix J. Talbot Jun 2024

Examining The Interaction Between Calcium Supplement Use, Demographics, And Lifestyle Factors On Bone Health Of Women, Vix J. Talbot

University Honors Theses

Osteoporosis is a condition which poses a significant health threat, particularly among women during the menopause transition, where accelerated bone loss increases fracture risk. Calcium supplementation has been shown to be an important intervention to mitigate bone mineral density (BMD) decline during this and other periods of life. However, the efficacy of calcium supplementation is influenced by various individual factors, including demographics and lifestyle habits. This study investigates the interaction between calcium supplement use, and several interaction terms on bone health in women. Multiple linear regression analysis is employed to assess the impact of these factors on BMD. Data from …


Henna Chatbot Capstone Review, Kobe Norcross Jun 2024

Henna Chatbot Capstone Review, Kobe Norcross

University Honors Theses

This thesis reviews the development of the Henna Chatbot, an AI-powered DEI consultant designed to provide personalized feedback to organizations. Sponsored by DEI consultant Arsh Haque, the project aims to address gaps in current DEI software, which often lacks team-specific feedback. The Henna Chatbot leverages GPT-3.5 Turbo to create an affordable SaaS platform where organizations can train Henna with their DEI values, and Henna will help organizations stay aligned with those values. The project spanned twenty weeks and was completed by a team of eight computer science students at Portland State University. The development process followed Agile methodologies, emphasizing effective …


Microplastic Pollution In Stormwater: Preliminary Findings From The Oregon Coast, Jazmine R. Compton Jun 2024

Microplastic Pollution In Stormwater: Preliminary Findings From The Oregon Coast, Jazmine R. Compton

University Honors Theses

Microplastics have become ubiquitous in marine environments and pose a risk to ecosystem, organismal, and human health. Stormwater runoff has been suggested to be a major contributor to marine microplastic pollution. This project aims to quantify the average concentration of microplastics in stormwater in a community on the Oregon Coast. To accomplish this, stormwater samples were collected from five sites in Cannon Beach, Oregon, and one sample was analyzed using a dissection microscope. Using this technique, the number, size, and composition of the microplastic particles were determined. The calculated concentration of microplastics in the stormwater sample was 12.21 MPs/L, and …


Student Perceptions: How Stem Students Value Belonging Interventions, Elizabeth A. Runkel Baez Jun 2024

Student Perceptions: How Stem Students Value Belonging Interventions, Elizabeth A. Runkel Baez

University Honors Theses

With the prioritization of increasing Science, Technology, Engineering, and Mathematics (STEM) graduates in the United States, researchers have become increasingly interested in how to promote STEM students’ sense of belonging. Sense of belonging is considered a marker of persistence in STEM. Facilitated ‘belonging interventions’ are one way to strengthen a sense of belonging amongst STEM students. How students respond to, value, and understand these belonging interventions is relatively understudied. In this study, focus groups were conducted with STEM students from a single university to investigate how they value an in-class belonging activity. Qualitative thematic coding of focus group responses revealed …


Differential Elliptic Flow Analysis Of Hadrons With Different Wuark Content In Simulated Pp Collisions, Elhussein Osama Jun 2024

Differential Elliptic Flow Analysis Of Hadrons With Different Wuark Content In Simulated Pp Collisions, Elhussein Osama

Theses and Dissertations

According to current physics theories, it is assumed that in the first microsecond after the big bang, the universe was in a state of matter called Quark-Gluon Plasma (QGP), where the fundamental consistent of matters (quarks and leptons), were highly energetic, and floating around freely. Searching for such phase of matter; as the possible earliest signatures after the big bang, and among many other interesting experimental measurements, the jet quenching and elliptic flow are the most important ones, in the heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC) experiments.

The azimuthal anisotropy …


Evaluating The Efficiency Of Low-Cost Air Quality Sensors At A Suburban Field Site, Olivia Wuttke Jun 2024

Evaluating The Efficiency Of Low-Cost Air Quality Sensors At A Suburban Field Site, Olivia Wuttke

Undergraduate Theses, Capstones, and Recitals

Science surrounding the use of low-cost sensors (LCS) to monitor air quality is rapidly expanding to satisfy the need to fill in regional air quality data gaps. This project evaluated the suitability of two types of LCS: Modulair-PM and PurpleAir (SD and Flex models) as efficient means to measure airborne particulate matter. The study involved physical installation of nine co-located sensors at a suburban site in Denver, connectivity troubleshooting as necessary, and data analysis/modeling of data over multiple months (19 weeks). PM data was compared between individual sensors of the same type, as well as across the two different sensor …


Establishment Of A Research Site At The Kennedy Mountain Campus For The Observation Of Airborne Particulate Matter, Alyssa Knaus Jun 2024

Establishment Of A Research Site At The Kennedy Mountain Campus For The Observation Of Airborne Particulate Matter, Alyssa Knaus

Undergraduate Theses, Capstones, and Recitals

This thesis explored particulate matter (PM) concentrations at two sites within the Colorado Front Range. The study utilized two models of PurpleAir PM sensors, Flex and SD-II, to provide real-time, accessible data on PM1, PM2.5, and PM10 mass concentrations with the goal of establishing the first research site at the Kennedy Mountain Campus (KMC). The first of the two sites used during this study was at a suburban location outside of Denver, CO. This period was used as an instrument intercomparison period in order to conduct instrument analysis. The initial findings from this period found significant correlations between PM concentration …


Piloting A Drain Gauge As A Method Of Measuring Runoff From Ecoroofs In Portland, Trinity Perrin Jun 2024

Piloting A Drain Gauge As A Method Of Measuring Runoff From Ecoroofs In Portland, Trinity Perrin

University Honors Theses

The following paper will be exploring a pilot methodology of a drain gauge system I built that’s used to calculate stormwater runoff from ecoroofs in Portland, Oregon. The drain gauge is a less studied technique for measuring ecoroof runoff, but holds high potential for developing better monitoring and management of ecoroofs within the city of Portland. What separates this stormwater runoff capturing device apart from other stormwater runoff calculation techniques is its adaptable design and simple installation. The drain weir can be placed in any roof drain that an ecoroof has been installed simply by placing it into a roof …


The Institutional Challenges Of A Quantified Self Study An Attempt To Ascertain How Data Collected From A Mobile Device Can Be An Indicator Of Personal Mental Health Over Time., Julian E. Lazaras Jun 2024

The Institutional Challenges Of A Quantified Self Study An Attempt To Ascertain How Data Collected From A Mobile Device Can Be An Indicator Of Personal Mental Health Over Time., Julian E. Lazaras

University Honors Theses

The adoption of an application of new technology always comes with a bias, this is never more true for the case of human behavioral analytics within higher education. While movements such as the quantified self movement make strides to reinterpret the realm of data analytics, psychology, and computer science, there are inevitably limitations to the adoption and application of such approaches within the standard realm of research. Herein is presented a case where an effort to evaluate the prospect of use of mobile phone data as secondary indicators of personal mental health through the lens of data analysis was put …


Cards With Class: Formalizing A Simplified Collectible Card Game, Dan Ha Jun 2024

Cards With Class: Formalizing A Simplified Collectible Card Game, Dan Ha

University Honors Theses

Collectible card games (CCGs) have been a wildly popular game genre since the release of Wizards of the Coast’s Magic: The Gathering. These games revolve around their thousands of cards and the hundreds of thousands of interactions they can create with their many effects. For designers, it is an incredibly demanding task to ensure that every single card works properly and that each card’s text unambiguously conveys its intended behavior in all cases. The task only grows more difficult over time as the number of cards in the game grows and card effects become more complex or experimental. If the …


Federated Learning Based Autoencoder Ensemble System For Malware Detection On Internet Of Things Devices, Steven Edward Arroyo Jun 2024

Federated Learning Based Autoencoder Ensemble System For Malware Detection On Internet Of Things Devices, Steven Edward Arroyo

Theses and Dissertations

New technologies are being introduced at a rate faster than ever before and smaller in size. Due to the size of these devices, security is often difficult to implement. The existing solution is a firewall-segmented “IoT Network” that only limits the effect of these infected devices on other parts of the network. We propose a lightweight unsupervised hybrid-cloud ensemble anomaly detection system for malware detection. We perform transfer learning using a generalized model trained on multiple IoT device sources to learn network traffic on new devices with minimal computational resources. We further extend our proposed system to utilize federated learning …


Feasibility Of Oil Palm Agroforestry System: Evaluating The Application Of Oil Palm Ash For Enhancing Cherry Tomato (Solanum Lycopersicum. Var. Nancy Rz) Production Using Brackish Water., Ime Joseph Bassey Jun 2024

Feasibility Of Oil Palm Agroforestry System: Evaluating The Application Of Oil Palm Ash For Enhancing Cherry Tomato (Solanum Lycopersicum. Var. Nancy Rz) Production Using Brackish Water., Ime Joseph Bassey

Theses and Dissertations

Monoculture systems of oil palm production are ravaging the world’s tropical forests, causing deforestation and biodiversity loss, which contribute to climate change at an uncontrollable pace. Oil palm agroforestry systems (AFSs), one of the strategies of regenerative agriculture, have proven to reverse the unfavorable effects of the oil palm monoculture systems. A sustainable means of soil fertilization and irrigation must be explored to improve the feasibility of oil palm AFSs. This study evaluates the impact of the application of oil palm ash and brackish irrigation on cherry tomato production. The experiment was conducted in a hydroponic system using a 2*4 …


On Limiting Distributions For Eigenvalue Spectra Of Sample Correlation Matrices From Heavy-Tailed Populations: Literature Review, Sachini Sandhareka Wijesundara Jun 2024

On Limiting Distributions For Eigenvalue Spectra Of Sample Correlation Matrices From Heavy-Tailed Populations: Literature Review, Sachini Sandhareka Wijesundara

Major Papers

This major paper offers an extensive review of literature concerning the limiting distributions for the eigenvalue spectrum of sample correlation matrices from a p-dimensional population, where both the dimension p and the sample size n grow to infinity. The study systematically categorizes the reviewed literature based on underlying assumptions regarding the data characteristics. Specifically, it examines several distinct cases: the independent and identically distributed (i.i.d) case with finite fourth moments, the i.i.d case with infinite fourth moments, the i.i.d case with infinite second moments, and scenarios where rows and columns of the data are linearly dependent. Additionally, the major paper …


Leveraging Biological Mechanisms In Machine Learning, Kyle J. Rogers Jun 2024

Leveraging Biological Mechanisms In Machine Learning, Kyle J. Rogers

Theses and Dissertations

This thesis integrates biologically-inspired mechanisms into machine learning to develop novel tuning algorithms, gradient abstractions for depth-wise parallelism, and an original bias neuron design. We introduce neuromodulatory tuning, which uses neurotransmitter-inspired bias adjustments to enhance transfer learning in spiking and non-spiking neural networks, significantly reducing parameter usage while maintaining performance. Additionally, we propose a novel approach that decouples the backward pass of backpropagation using layer abstractions, inspired by feedback loops in biological systems, enabling depth-wise training parallelization. We further extend neuromodulatory tuning by designing spiking bias neurons that mimic dopamine neuron mechanisms, leading to the development of volumetric tuning. This …


The Robot On The Hill, James Ryan Jun 2024

The Robot On The Hill, James Ryan

College of Computing and Digital Media Dissertations

“The Robot on the Hill” is a rogue-like autobattler that procedurally models the state of the individual in the information age. The game abruptly transitions between diverse framings - a hill, a bedroom, a pond, a chessboard, the void - in order to highlight the disjointedness that is present in the informationalizing of self and reality. It dialogues with Byung Chul Han and Heidegger to portray what Han describes as a ‘narrative crisis’ in modernity and the devaluation of experience. When the value of experience diminishes and disintegrates, “all that is left is bare life, a kind of survival.” …


Land-Use Governance And Indigenous Engagement In Arctic Alaska And Norway: Successes, Current Gaps, And Paths Forward, Ningning Sun Jun 2024

Land-Use Governance And Indigenous Engagement In Arctic Alaska And Norway: Successes, Current Gaps, And Paths Forward, Ningning Sun

Environmental Studies Senior Theses

This study aims to analyze the land use governance structures and the role of Indigenous engagement in Alaska and Norway using a comparative approach, with special focus on successful practices, current gaps, and paths forward to achieve equitable governance. Extractive land uses, such as oil and gas extraction and the construction of wind farms, have mixed impacts on Indigenous communities and lead to social and legal issues such as land use conflict and environmental injustice. Previous research has studied land use governance in Arctic countries with regard to Indigenous Peoples, yet there is a lack of literature that spans Alaska …


Fiscal Incentives For Green Growth: A Mixed-Methods Study Of The State Of Agroforestry And Tree Cover In India, Spriha Pandey Jun 2024

Fiscal Incentives For Green Growth: A Mixed-Methods Study Of The State Of Agroforestry And Tree Cover In India, Spriha Pandey

Environmental Studies Senior Theses

Agroforestry is a crucial strategy for diversifying farmer livelihoods and achieving India's climate goals, but its adoption has been hindered by institutional and fiscal obstacles. This mixed-methods study investigates the impact of national government schemes on tree cover increase and expert perceptions of incentives and barriers to agroforestry adoption. Our analysis of national schemes from 2013-2017 reveals that effective fiscal mechanisms and policy cohesion are critical drivers of agroforestry growth. Specifically, we find that increased funding for the Rural Employment Guarantee Scheme (MGNREGS) is associated with significant increases in tree cover area while funding for the Horticultural Scheme (NHM) is …