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Modeling, Synthesis, And Experimental Characterization Of Rhenium Disulfide For Optoelectronic Devices, Solomon Opeyami Ojo

Graduate Theses and Dissertations

Two-dimensional (2D) transition metal dichalcogenides (TMDs) have garnered considerable interest for their potential in optoelectronics and photonics owing to their remarkable combination of electronic, optical, and mechanical properties. These characteristics distinguish them from other 2D materials, including graphene, making them particularly valuable for next-generation technologies. This dissertation focuses on ReS_₂, a 2D TMD with a unique anisotropic 1T distorted crystal structure. The research aims to elucidate its fundamental properties through a combination of theoretical modeling, material synthesis, and experimental characterization techniques, with the goal of optimizing ReS_₂ for device applications. A theoretical investigation utilizing Density Functional Theory …

Enhancing Smart Grid Security And Resilience Using Programmable Networks, Zheng Hu

Graduate Theses and Dissertations

The security and resilience of smart grids are essential to ensuring reliable and efficient energy distribution, especially as these cyber-physical systems grow more interconnected and complex. Supervisory Control and Data Acquisition (SCADA) systems play a critical role in smart grid operations by enabling essential infrastructure control and real-time monitoring. However, SCADA systems are highly vulnerable to modern cyber threats, which target weaknesses in industrial protocols and real-time data requirements.

This dissertation investigates the potential of programmable network technologies, with a focus on P4 (Programming Protocol-independent Packet Processors) switch, to deliver adaptable, in-network security solutions tailored to the needs of smart …

Design And Fabrication Of Graphene Solar Cells For Low-Power Energy Harvesting Systems, Tamzeed Bani Amin

Graduate Theses and Dissertations

This study presents the design and fabrication of graphene-based Schottky junction solar cells integrated into a 3-volt power system for low-power applications. Utilizing standard semiconductor processing methods, including selective oxide removal, metal contact deposition, and large-area graphene transfer, we fabricated solar cells from a silicon wafer coated with a thermal oxide layer. Each individual solar cell generated up to 270 µA of short-circuit current and an open-circuit voltage of 420 mV under illumination. We connected multiple solar cells in series to produce a total output of 3.3 volts, which is sufficient to recharge a 3-volt battery. The system, comprising these …

Predicting Different Psychological Profiles Amongst Substance Users., Zach J. Gray

Graduate Theses and Dissertations

Substance use disorders (SUDs) are some of the most prevalent issues facing society. As SUDs are highly individualized in how they manifest, recent work has attempted to classify distinct profiles of drug users to better understand what factors put someone at risk for shifting from casual substance use to developing a substance use disorder (SUD). Common risk factors for SUD development include stressor exposure, difficulties with emotion regulation, personality, and risky decision-making. As many of the behaviors that constitute SUDs are exhibited prior to potential diagnosis, developing “profiles” that combine these traits and experiences could eventually predict SUDs. The current …

Comparison Of Statistical And Machine Learning Genomic Prediction Methods In Plant Breeding: Case Studies In Maize And Soybean, Igor Kuivjogi Fernandes

Graduate Theses and Dissertations

Plant breeding is essential to increase genetic gain and food production worldwide. This study was conducted to evaluate new ways to use machine learning (ML) to tackle plant breeding challenges, where two ideas were tested — the first chapter focuses on how to combine genetic and environmental data using ML to improve the prediction of maize grain yield in multi-environment trials, while the second chapter centers on how to couple feature selection of molecular markers with ML to enhance prediction of yield in soybean, and, in both cases, ML approaches were compared to well-established statistical methods greatly adopted by the …

A Volumetric Model Of Ree And Other Critical Element-Bearing Underclay Deposits In The Eckley Mine Area, Luzerne County, Pennsylvania, Harrison Spiller

Graduate Theses and Dissertations

The Eastern Middle Anthracite Field in southern Luzerne County, Pennsylvania was investigated for potential quantities of critical minerals, including rare earth-bearing minerals (REE) present in underclay deposits associated with coal measures of an existing anthracite coal mine. This work is built on Department of Energy/National Energy Technology Laboratory (DOE/ NETL) 2016 work on samples from the Eckley Mine near Hazelton, Pa. which discovered elevated contents of some critical minerals in core from a single wellbore. This thesis reports on new and additional information collected from that area through geological field work, detailed conventional core descriptions, stratigraphic cross sections, and spectral …

First Latter-Day Saint Women Baptized In Europe And Oceania: Ann Cottam Dawson (1785-1849) And Terii (Ca. 1800-Ca. 1860), Robyn Shahan Spears

Graduate Theses and Dissertations

This dissertation is a study in the backgrounds, Latter-day Saint conversions, and ministries of two early nineteenth-century women: Ann Cottam Dawson in Lancashire, England and a woman known simply as Terii on the island of Tubuai in the Austral Islands (now French Polynesia). Because these two women did not leave behind diaries, this study relies upon evidence such as missionary diaries, newspapers, church records, vital records, genealogical records, sermons, and even a mutiny narrative. The discussion is organized in three parts: Dawson’s biography, Terii’s biography, and a comparison of the two. Both women fed and housed the missionaries, performed women’s …

Comparing And Evaluating Models Of Tile-Assembly Using Intrinsic Simulation, Daniel Hader

Graduate Theses and Dissertations

Tile-assembly studies abstract models of computation inspired by advancements in the emerging field of DNA-nanotechnology, where synthetic strands of DNA are used as building blocks for microscopic structures. These DNA strands can be made to combine into structural units with selectively sticky sides that abstractly resemble Wang tiles. However, unlike Wang tiles, an assembly process is modeled where tiles combine one-by-one to form larger assemblies according to matching rules based on their sticky sides. While in practice, these tile-assembly models have seen use in designing DNA nano-structures, the mathematical study of their theory has revealed an exciting interplay between geometric …

Exploring The Impact Of Generative Ai Prompt Engineering In Higher Education: A Study In Undergraduate And Graduate Business Analytics Courses, Jana Gastineau

Graduate Theses and Dissertations

The rapid evolution of generative artificial intelligence (GenAI) presents a transformative opportunity in higher education, offering new pathways for learning through personalized feedback, interactive environments, and support for complex tasks. This quasi-experimental study investigated the effects of targeted GenAI prompt engineering instruction on knowledge acquisition, prompt writing skills, and confidence levels among undergraduate and graduate students in business analytics courses at a research university. A pre-test and post-test design measured changes across knowledge acquisition, prompt writing proficiency, and GenAI confidence and usage. Findings revealed a mixed impact on knowledge acquisition, with undergraduates showing minor improvements and graduate students experiencing declines …

Towards Robust And Fair Vision Learning In Open-World Environments, Thanh-Dat Truong

Graduate Theses and Dissertations

The rapid increase of large-scale data and high-performance computational hardware has promoted the development of data-driven machine vision approaches. Advanced deep learning approaches have achieved remarkable performance in various vision problems and are closing the capability gap between artificial intelligence (AI) and humans. However, towards the ultimate goal of AI, which replicates human ability in visual perception tasks, the machine vision learning methods still need to address several ill-posed challenges. First, while the current vision learning methods often rely on large-scale annotated data, the data annotation process is a costly and time-consuming process. Second, the unfaired predictions produced by vision …

Addressing Cybersecurity Data & Workforce Scarcity With Troy: Testbed For Resilient Operational Systems, Henry Oliver Schmidt

Graduate Theses and Dissertations

Machine learning has seen an explosive rise in the past decade. Companies, organizations, and governments are racing to pursue the advancements and insight provided by machine learning powered tools. However, to get effective and meaningful insights from machine learning models a significant amount of detailed data is required to train them. This poses a problem in fields where data is not openly available, such as cybersecurity. Entities are often unwilling to give out network or system data to the public for machine learning and cybersecurity research since that data can contain sensitive or proprietary information. The risk simply outweighs the …

Investigating Consumer Perception And Wine Quality Impact On Alternative Packaging On Grape (Vitis), Mark Walker Bartz

Graduate Theses and Dissertations

The grape (Vitis species) and wine industry has major global economic impacts but faces issues with sustainability. The use of glass bottles for wine production is environmentally unsustainable due to energy-intensive manufacturing and poor recycling rates. However, wine consumers tend to associate glass bottles with higher quality over alternative wine packaging materials such as aluminum, polyethylene terephthalate (PET), and flexible bags/pouches. Since wine price and packaging influence consumers perception of wine quality, wine producers need to understand consumers to maximize profits. Thus, the overall objectives of this research were to investigate consumer perception and wine quality impact of alternative …

Enhancing Selection Intensity With High-Throughput Phenotyping Data In Plant Breeding, Ashmita Upadhyay

Graduate Theses and Dissertations

Genomic prediction (GP) has proven to be an essential tool to accelerate the cultivar development pipeline by predicting the performance of un-phenotyped lines in the field of plant breeding. However, the prediction accuracy is bounded by the heritability of the target trait, limiting the efficiency of the single-trait GP model. To overcome the limitation, a multi-trait genomic prediction model using high-throughput phenotyping (HTP) data can be used to leverage secondary traits to boost the predictive ability of the target trait. This study aimed to assess the efficiency of the multi-trait (MT)- GP model powered by HTP derived secondary traits in …

A Cmos Ldo Voltage Regulator For Low Power Applications, Nicolaus Vail

Graduate Theses and Dissertations

This thesis presents the design, simulation, layout, and testing of a low dropout linear voltage regulator (LDO) in a 180 nm CMOS process. The LDO is intended for use in low-power, battery-operated applications, and it has an adjustable output for a variety of different implementations. It can supply up to 100 mA of current, which is enough to power many small electronic circuits. It has a dropout voltage of 150 mV, and it consumes less than 200 μA of current during operation, which is on par with many commercial regulators. The line regulation is also comparable to commercially available LDOs, …

I'M Just Me: The Rhetorical Study Of Veterans’ Experiences Of Academic Labels In College Classrooms, Taylor Weeks

Graduate Theses and Dissertations

This project seeks to provide a glimpse into the impact of academic labels on student veterans via the student veterans' own voices. This project reflects on and builds from previous research projects that involve transition theories and pedagogical theories in the field of writing studies as well as veteran studies that involve student veterans. Through a locally situated multi-case study qualitative approach using questionnaires and interviews, I examine to what extent do academic labels have on student veterans from the student veterans’ own voices. Finally, I offer implications of this project for writing instructors, administrators, and future researchers involving student …

Wind Tunnel Investigation Of The Along-Wind Dispersion In Finite-Duration Neutrally Buoyant Gas Releases, Daniel Williams

Graduate Theses and Dissertations

This thesis investigates the along-wind dispersion of hazardous gas releases within a turbulent boundary layer using controlled experiments in an ultra-low-speed wind tunnel, recognizing the limitations of numerical modeling and field tests. This study utilizes a neutrally buoyant gas mixture and dual Flame Ionization Detectors (FIDs) to capture representative, repeatable data on gas cloud behavior over finite durations. Ensemble averaging of 65 trials across varying release durations and downwind distances provided detailed insights into gas dispersion and the distinct time phases within finite-duration releases. Analysis revealed that along-wind dispersion coefficients depend on turbulence and vertical wind shear, with normalized coefficients …

Intersectionality And Career Persistence Of African American Women In Cybersecurity Careers: A Narrative Inquiry, Monica Marquita Jones Prewitt

Graduate Theses and Dissertations

The purpose of this narrative inquiry is to examine the experiences of African American women working in cybersecurity, a male-dominated field. An intersectional lens will be used in the study to provide insight into their positionality as women of color in a male-dominated career field. The study will examine the stories of the women who persisted in the field and the existing influences or interventions that supported their retention. This pre-registered study will provide the framework for this study to be completed at the University of Arkansas. The researcher will use a descriptive phenomenological approach and semi-structured interviews to understand …

Cognitive Bias, Memory, And Fearfulness Of Red Jungle Fowl And Athens Canadian Random Bred Chickens, Victor Juwon Oyeniran

Graduate Theses and Dissertations

Our understanding of how poultry perceive and interpret their environment is essential to enhancing their welfare; over the years, animal welfare science has relied on measures of the behavioral and physiological components of affective states (positive and negative) as welfare indicators. There is an increasing interest in the study of chicken’s affective states using the Judgment bias test (JBT) as a tool for assessing welfare through their responses to ambiguous cues. This study investigates the cognitive performance of two chicken breeds with different evolutionary histories: Red Junglefowl (RJF), the primary ancestor of modern chickens, and Athens Canadian Random Bred (ACRB), …

Filipino American Cultural Beliefs And Perceptions Of Autism, Emily-Anne Sevilla Del Rosario

Graduate Theses and Dissertations

Not much is known about Filipino American beliefs of autism due to the novelty of the research area. Most research has been conducted in Asian American populations disregarding the uniqueness of each cultural subgroup. The purpose of the present study was to reach out to Filipino Americans and understand their perceptive of autism along with the potential barriers to seeking out help for concerns of autism traits through a mixed-method study. Results indicated the important roles that acculturation and religion play on the likelihood of seeking medical professional help. Qualitative interviews suggest three major themes that characterize Filipino American support …

Blend Matters: Interactions Of Rice Cultivars On Milling, Physico-Chemical & End Use Traits, Bindu Regonda

Graduate Theses and Dissertations

Rice blending or mixing of different rice cultivars, a common practice in the industry, significantly impacts processing efficiency and end-product quality, yet its effects on end products remain understudied. This research investigated the implications of blending contemporary Arkansas rice cultivars through two comprehensive studies focusing on milling yields and physicochemical properties, instantization, and parboiling processes. Five long-grain cultivars, including hybrids (RT 7521 FP, RT 7321 FP, XP 753) and purelines (Ozark, CLL 16), were blended in various combinations and different drying.

The first study revealed that blending significantly affected milling yields and physicochemical attributes. Pre-drying blending yielded better results compared …

Bactericidal Mechanism Of Peracetic Acid Against Salmonella Mediated By Reactive Oxygen Species, Mohammed Khalid Wheib Al-Doury

Graduate Theses and Dissertations

Peracetic acid (PAA) is extensively used as a bactericidal agent in poultry processing to reduce foodborne pathogens, including Salmonella enterica serotype Typhimurium (S. Typhimurium). Despite its widespread application, the exact mechanisms underlying its bactericidal effects, particularly the role of reactive oxygen species (ROS), remain incompletely understood. This dissertation examines the role of ROS in PAA-mediated bacterial killing and explores both genetic and metabolic factors that influence bacterial susceptibility to PAA. Findings from these studies have implications for enhancing the efficacy of PAA, thereby improving food safety practices in the industry.

The first study investigates ROS as a central component …

An Investigation Of The Effect Of Performance Engineered Mixture (Pem) Design On Durability And Air Void Matrix Of Concrete Pavements, Jacob Ortlieb

Graduate Theses and Dissertations

Performance Engineered Mixture (PEM) design is a novel method of creating concrete pavement that is economical achieving desirable performance properties such as durability, strength, and workability. Performance-based design is critical for concrete pavements, so the fresh concrete can be placed without issue and the hardened concrete can withstand deterioration and environmental damage such as freezing and thawing. To achieve economical concrete, PEM utilizes tools such as the tarantula curve for aggregate grading, and the Super Air Meter (SAM) test, providing information regarding the air void matrix while the concrete is fresh. To achieve these properties with less cement will lead …

Ecopedagogy In Action: The Landfill Project, Marriah Geels

Graduate Theses and Dissertations

This is an art education action research project that analyzes how an interdisciplinary ecopedagogical curriculum experience may impact student perspectives on waste (specifically trash) and the human impact on the environment. The four-week curriculum incorporated choice-based art education, place-based education, and slow pedagogy to better understand how students’ perspectives changed or remained constant throughout. This curriculum was taught to four class periods in a high school setting with about 34 students in 9-12th grade. Qualitative data collection included a pre and post-survey, visual journals, classroom observations, artist statements, and artwork. Through the analysis of Pre/Post Surveys by utilizing hybrid coding …

The Potential Of Trash: Re-Claiming Creative Authority, Jana Whatley

Graduate Theses and Dissertations

This project-based thesis catalogs the planning, building, and engagement with community resource libraries that made second-hand art materials available to the community for free. The micro-libraries hold materials that individuals, organizations, and companies have donated. Materials include single-use plastics, off-cast materials from commercial production, and second-hand or leftover art materials. Four material libraries for creative reuse are in four art education institutions in the greater Northwest Arkansas region. The project sews seeds of mutually supportive systems within regional public art institutions and promotes the creative reuse of materials often tossed into local landfills. As a teaching artist, I have long …

Applying Uas Lidar For Developing Small Project Terrain Models, Ashraf Siddiqui

Graduate Theses and Dissertations

Unmanned aerial systems (UAS) LiDAR was used to collect survey data for small-area projects, particularly bridge replacement projects. The project aimed to compare UAS LiDAR data with conventional surveying methods. For the project, five bridge sites were selected for UAS LiDAR and conventional survey data collection, which include Lincoln Bridge 1 (East), Lincoln Bridge 2 (West), Humnoke, Frenchman’s Bayou, and Mountain Home. Data for each site was collected during the 2021–2022 winter. A DJI M600 Pro and Phoenix LiDAR Systems AL3-16 LiDAR unit were used for the UAS LiDAR measurements. The conventional survey equipment used included a global navigation satellite …

Reflecting On Being Good Enough: Tracing A Journey Of Identifications And Unraveling Denial Of The Queer Self, Lucero Aguirre

Graduate Theses and Dissertations

“Good Enough” is a thesis written to unpack reflection on assimilatory forces during early life experiences in education. By documenting self-reflections, utilizing arts-based research methods, and examining theory relative to theories of identity formation, I use a screenplay in the format of a fictional talk show where three golden retrievers are interviewed from notable Disney films Homeward Bound: The Incredible Journey (Dunham, 1993), Air Bud (Smith, 1997), and UP (Docter, 2009). I connect the golden retriever as a symbol representing aspects of the American dream, an influence shaping my identity and merit-focused alliance with dominant identities. The fictional plot of …

Friendship Intimacy: A New Approach To Valuing Friendship, Benjamin Lugo

Graduate Theses and Dissertations

There is a tradition in moral theory that holds that friendship is necessary for living well. That is, if our aim is to live a good life or a flourishing life, then that life will include building and maintaining friendships. Aristotle and Plato both share this view and express similar claims about the necessity of friendship for the pursuer of a good life. Contemporaries of both have spent time interpreting their claims and have long commented on the intrinsic value of friendship. I pick up on a strand of the debate by exploring the purported value of friendship. While considerable …

What Is A Person? How Does One Become A Morally Good Person? The Intuitive View!, Tancredo Tivane

Graduate Theses and Dissertations

This thesis centers around two philosophical problems: the concept of a person and the process by which one becomes a morally good person. Drawing on the works of philosophers such as Harry Frankfurt, Strawson, and A.J. Ayer, it begins with an inquiry into what it means to be a person. It argues that while humanhood, with its rational capacities, is a contingent rather than a necessary condition, it can serve as an accurate predictor of personhood. The thesis posits that personhood is an achievement rather than an inherent state, facilitated by interactions within a social framework that refine these rational …

Ω-Shaped Rogowski Coil Current Sensor Optimization Design In Power Electronics Applications, Xia Du

Graduate Theses and Dissertations

Accurate switching current measurement plays a pivotal role in characterization of power devices, overcurrent protection, and real-time control of system-level operations in power electronics applications. However, the ongoing revolution in power electronics, driven by the emergence of wide bandgap power devices operating at megahertz (MHz) switching frequencies, introduces challenges for current sensor design. The urgent issue now is the need to increase current sensor bandwidth significantly to adeptly capture the rapid switching speed current. Additionally, the trend towards high power density and compact power converters in various applications demands current sensors that are not only compact and nonintrusive but can …

The School Lunchroom As An Important Context In Children’S Social Development: The Link Between Lunchtime Peer Acceptance And Peer Victimization, Jake Callaway Steggerda

Graduate Theses and Dissertations

Steggerda et al. (2022a) found that children’s self-reported lunchtime peer acceptance was predictive of later experiences of peer victimization. These authors speculated that the link between lunchtime peer acceptance and peer victimization is mediated by children’s internalizing or externalizing problems. The current study adds to the field’s understanding of the link between children’s lunchtime peer acceptance and peer victimization by considering whether internalizing symptoms and externalizing problems are potential mediating variables. Participants were 659 children from 34 classrooms (M age 9.31 years, SD = 0.50; 50.7% female; 42.7% Hispanic/Latinx, 30.3% White, 10% Pacific Islander, 7.8% bi/multiracial, 2.2% American Indian, 2.2% …