Digital Commons Network^™

Optical And Thermal Characterization Of Vertically Conducting Β-Ga₂O₃ Diodes Grown On 4h-Sic Substrates For Short-Wavelength (<254 Nm) Detection, Muhammad Hassan Tahir

Theses and Dissertations

The advancement of compact, thermally stable, and efficient devices for deepultraviolet (DUV) detection below 254 nm is critical for solar-blind sensing, radiation monitoring, and high-power electronics. This thesis presents the growth, fabrication, and detailed optical and thermal characterization of vertically conducting β-gallium oxide (βGa₂O₃) Schottky barrier diodes (SBDs) grown on n-type 4H-Silicon Carbide (4H-SiC) substrates using metal-organic chemical vapor deposition (MOCVD).

β-Ga₂O₃ is an ultra-wide bandgap (UWBG) semiconductor (~4.8 eV) with intrinsic DUV transparency and high breakdown electric field, making it an ideal candidate for short-wavelength photodetection. However, its low thermal conductivity limits its vertical device performance. To overcome this, …

Modeling The Interaction Between Pain And Movement: Insights From Brain Activation Patterns And Context-Dependent Emotion In Chronic Low Back Pain, Pradeep Kumar Sahu

Theses and Dissertations

In persons with chronic pain, fear or anxiety related to movement is a well-established model under the biopsychosocial framework that explains in part, the chronicity of symptoms commonly reported by individuals with chronic low back pain (cLBP). This dissertation aimed to further understand the link between the context-dependent emotion network in the brain and movement in two separate studies using brain functional MRI and autonomic nervous system indices. Aim 1sought to investigate the brain functional connectivity linking brain regions involved in context-dependent emotion and movement while cLBP participants moved their back inside the scanner by performing a modified trunk bridging …

Effect Of Growth Conditions On The Performance Of Vertically Conducting Beta-Ga2o3 Diodes On 4h-Sic Substrate By Mocvd, Nifat Jahan Nipa

Theses and Dissertations

This thesis highlights the critical influence of doping strategies, specifically co-delta doping with silicon (Si) and indium (In), on improving the structural quality and device performance of β-Ga₂O₃-based Schottky barrier diodes (SBDs). To achieve better thermal management, β-Ga₂O₃ thin film was grown on bulk 4H-SiC substrates using the Metal-Organic Chemical Vapor Deposition (MOCVD) technique, renowned for its precise control over composition, thickness and doping profile. The ultra-wide bandgap (UWBG), high critical breakdown field and low turn-on resistance of β-Ga₂O₃ make it a strong candidate for next-generation power electronics and short-wavelength detection in extreme environments. However, the presence of structural defects …

Effects Of Verbal Tasks On Driving Simulator Performance, Jonathan Cheshire Rann

Theses and Dissertations

We report the results from a driving simulator paradigm we developed to test the effects of simple verbal tasks on simultaneous driving performance. A total of 74 undergraduate students participated in two experiments in which they controlled a car using the steering wheel to track a moving target. The dependent measure, overall deviation from target, was continuously recorded. Experiment 1 (E1) tested tracking performance during slow and fast target speeds under conditions involving either no verbal input or output (Absent), passive listening to spoken prompts via headphones (Listen), or responding to the spoken prompts (Respond). Experiment 2 (E2) was similar …

Stimulation Of The Rostromedial Tegmental Nucleus Induces Long-Lasting Avoidance Behavior, Jacob Ryan Watson

Theses and Dissertations

The role of midbrain dopamine (DA) activity in reward seeking and reinforcement learning is well-documented, contrasting the lesser-understood impact of inhibitory signaling on DAergic activity, especially in the context of aversive learning and avoidance. The rostromedial tegmental nucleus (RMTg) is a GABAergic midbrain structure activated by aversive stimuli and exerts inhibitory influence over ventral tegmental area (VTA) DAergic activity in response to aversive consequences. Stimulation of the RMTg decreases the firing rate of VTA DA neurons and direct inhibition of the RMTg – VTA circuit enhances persistent reward seeking despite aversive consequences, a major criterion of substance use disorder (SUD). …

Clinical Correlates: Using Case-Based Learning In The Physician Assistant Classroom, Pamela Schindler Wilson

Theses and Dissertations

Physician Assistant (PA) education is rigorous and comprehensive. In only 27 months, the students must learn medical knowledge and skills for effective patient care. Instruction must be efficient and effective to teach these students how to be safe and functional PAs. Of primary concern is teaching students how to perform like clinicians, which requires critical thinking, self-directed learning, and teamwork.

This convergent, mixed-methods action research explored the impacts of case-based learning (CBL) in the PA classroom. The findings support using CBL to develop clinical reasoning skills, improve comprehension of the material, and develop self-directed learning skills. CBL requires the students …

Lessons In Game Use: Examining Engagement And Content Knowledge With The Use Of Digital Game-Based Learning Lessons In Biology, Rebecca Anne Valencia

Theses and Dissertations

According to both national and local data, students in high school biology classes are disengaged in content learning and do not demonstrate sufficient understanding of the content taught during units focused on the mechanisms of heredity and gene expression. Traditional teaching methods do not hold their interest which leads to disengagement and missed learning opportunities. The purpose of this action research was to evaluate the effect of digital game-based learning lessons on biology 1 students’ engagement and content knowledge application regarding the mechanisms of heredity and gene expression, as well as on the students’ perceptions of their digital game-based learning …

Explainable Process Recommendation Through Multi-Contextual Grounding Of Dynamic Multimodal Process Knowledge Graphs, Revathy Venkataramanan

Theses and Dissertations

Can I eat this food or not? Is this food suitable for diabetes and why? Which AI pipeline is best suited for a given task and dataset? How should an end-to-end pipeline be constructed? These questions differ from factual question-answering tasks. Recipes and AI pipelines are processes consisting of several entities interacting with each other. A recipe consists of ingredients, cooking methods, and their interactions, while an AI pipeline includes datasets, preprocessing techniques, models, hyperparameters, tasks, and results. Each entity must be analyzed individually, and collective inferencing is performed to derive the final decision. This decision-making process, known as compositional …

Understanding Verbal Irony: A Contrastive Analysis Of Personal And Informational Common Ground, Ruhan Çoban

Theses and Dissertations

This study investigates how representations of personal common ground (PCG; viz., close relationships vs. strangers) and informational common ground (ICG; viz., shared world knowledge) interact in shaping a reader’s comprehension of verbal irony in fictional narratives. While previous research has shown that greater familiarity among story characters enhances readers’ comprehension of ironic statements made by the characters (Gibbs, 2000; Kreuz et al., 1999; Kreuz & Link, 2001; Pexman & Zvaigzne, 2004), the interplay between representations of PCG and ICG remains understudied. In this study, we assumed that ICG takes precedence over PCG. Accordingly, we predicted that irony comprehension would be …

Assessing Health And Academic Disparities In The Deep South: The Enduring Impact Of Segregation And Redlining In Georgia, Bridget Hamilton

Theses and Dissertations

Background: Within the American South, marginalized Black populations continue to suffer from health disparities. A key resource that could aid in the prevention of health disparities such as teen pregnancy is the school nurse. School nurses are well positioned to assist in the development of independent health maintenance among student populations. However, school nurses remain understaffed and underfunded throughout most of the United States, which limits their effectiveness. It is possible that within southern states there are inequities in how school resources are allocated that have ties to segregation and redlining practices that systemically marginalized Black populations throughout the 1900s. …

Database Development For Reliable Small Object Detection In Maritime Environments, Jacob Matthew Whisenant

Theses and Dissertations

Achieving high reliability in small object detection is critical for advancing maritime and littoral intelligent navigation operations. Computer vision provides an undetectable form of perception that can be easily integrated into existing camera systems, offering a low-profile yet powerful solution for navigation and situational awareness in water-based environments. While deep learning techniques have significantly advanced the field of computer vision, the detection of small objects remains a persistent challenge. Limited pixel representation, the scarcity of large-scale small object datasets, and the reduced detail and indistinct features of small objects complicate detection efforts, especially in complex environments. These factors collectively hinder …

Aggressive, Adaptive, And Underestimated: From Allergy To Arboviruses, The Rise Of The Lone Star Tick, Emily Ellen Owens Pickle

Theses and Dissertations

Once considered a nuisance with little medical importance, the lone star tick (Amblyomma americanum, Acari:Ixodidae) has emerged as a formidable vector driving a new era of public health threats across the United States of America. This dissertation traces the rise of the lone star tick from obscurity to infamy, exploring its expanding geographic range, unique immunologic impacts on humans, and role in the transmission of emerging tickborne viruses. Through a series of integrated studies, this work characterizes the epidemiology, immunology, and ecological context of tick-borne diseases in the southeastern U.S., with a particular focus on α-Gal syndrome (AGS), …

Self-Efficacy And Mathematical Identities In A Rural Georgia Middle School Classroom, Gavin Wilson

Theses and Dissertations

Even into adulthood, some people have a strong resentment of math. Their beliefs toward their mathematical abilities have created a fear of the subject, resulting in an avoidance of anything math-related. These thoughts and beliefs regarding math and mathematical abilities begin somewhere along an individual’s academic journey in a math classroom. This action research study, using a mixed-methods approach, attempted to uncover the origins and development of self-efficacy and mathematical identities in rural eighth-grade students. Furthermore, this study explored ways that a teacher can influence these sets of beliefs and examined the impact on academic performance. The framework used to …

Multi-Task Deep Learning Approach For Segmenting And Classifying Competitive Swimming Activities Using A Single Imu, Mark Shperkin

Theses and Dissertations

Competitive swimming performance analysis has traditionally relied on manual video review and multi-sensor systems, both of which are resource-intensive and impractical for everyday training use. This study investigates whether a single wrist-worn inertial measurement unit (IMU) can be used to automatically segment and classify swimming activities with high accuracy. We propose a multi-task deep learning pipeline based on the MTHARS (Multi-Task Human Activity Recognition and Segmentation) architecture introduced by Duan et al. to perform stroke classification, lap segmentation, stroke count estimation, and underwater kick count estimation. Data were collected from eleven collegiate-level swimmers wearing left-wrist-mounted IMUs, each performing five 100-yard …

Process-Grounded Knowledge-Infused Learning And Decision Making, Kaushik Roy

Theses and Dissertations

This dissertation introduces process-grounded knowledge-infused learning and reasoning, a novel framework for integrating domain-expertise-based process knowledge into the learning and reasoning mechanisms of artificial intelligence systems. This approach is designed to produce controlled, transparent, and reliable predictions in critical tasks such as medical diagnosis and recommendation. By focusing on the case study of mental illness diagnosis and recommendation—where decision-making must be grounded in processes such as disorder-specific diagnostic criteria—this work demonstrates methods to embed structured decision-making directly into the system architecture during both training and inference. This integration facilitates end-to-end training and reasoning while ensuring that outputs strictly adhere to …

Circannual And Kinship Cues Shape Reproduction And Epigenetic Aging In Peromyscus, Kim Tuyen Huynh Dam

Theses and Dissertations

Evolutionary success is defined by the ability of a species to adapt and survive across many generations. This success is not determined by any single attribute but rather includes the entrenched, complex system that could be associated with biological rhythms, reproductive strategies, and regulations of epigenetic and genetic components. By using closed Peromyscus colonies as a model and by coupling mathematical modeling, analyses of breeding records, epigenetic studies, and in vitro and in vivo experiments, this dissertation aims to discover how Peromyscus adjusts to the internal and external pressures to ensure their survival and preserve evolutionary fitness in controlled environments. …

How Do People Discern Authenticity From Emotional Expressions, Sewon Oh

Theses and Dissertations

Emotional authenticity is a crucial element in the development and progression of social relationships. However, limited research has comprehensively examined how emotional authenticity perception is shaped by different communication channels, visual attention, and individual differences. This thesis aimed to investigate the emotional authenticity perception from multiple perspectives, including the feasibility of authenticity manipulation, the influence of multimodal cues, and visual attention allocation in assessing authenticity from facial expressions. Findings demonstrated that authenticity could be successfully manipulated by both professional and non-professional actors. Participants differentiated both authenticity and emotion most accurately in audiovisual expressions. The audio channel played an important role …

Action Research To Explore The Use Of Augmented Reality To Support High School Students In Understanding And Creating Art Work In A Drawing Course, Alicia Joanne Cobler

Theses and Dissertations

High school students in Drawing 1 at a high school in South Carolina struggle to understand meaning or make personal connections to their own artwork. The purpose of this action research was to evaluate the implementation of immersive reality technology, specifically augmented reality (AR), in art for high school Drawing 1 students to help them understand meaning in art and create their own meaningful artwork. Creating personally meaningful symbolic works of art is one of the first Visual Art National Core Standards (National Core Visual Art Standards, 2014). Creating meaning in artwork allows students to understand society, provide an opportunity …

Reduced Order Model-Based Framework For Microsecond Model Updating Of Two-Dimensional Structural Systems Using The Local Eigenvalue Modification Procedure, Emmanuel Abiodun Ogunniyi

Theses and Dissertations

Real-time model updating is crucial for active structures and electronic assemblies subjected to high-rate dynamic events. High-rate dynamic events refer to events that occur at high speeds and with rapid changes in the forces and energy involved. These events can include explosions, impacts, and crashes. These systems are characterized by a high dynamic response with a high rate (< 100 ms), high amplitude (> 100 gn), highly nonlinear, meaning that the response is not proportional to the applied force, and involve complex interactions between multiple objects or materials. A system exposed to high-rate dynamic environments is frequently prone to rapid plastic deformation, involving violent and …

Sensing Others, Alissa Reed

Theses and Dissertations

In this project, I notice how we listen and respond to animals, both through marine bioacoustics studies and rhetorical theory, and consider how we might develop new ways of noticing and interacting with animals. I hold together rhetorical theory, marine bioacoustics studies, and my observations nest sitting sea turtles to see what kind of multispecies ethic emerges from messy encounters with nonhuman others – specifically, with sea turtles nesting on the beaches of the Outer Banks in the Summer of 2020. By confronting the unavoidable moments of indecision, and even possible violence, inherent to encounters with nonhumans others, even and …

Regression With Atypical Data: Measurement Error, Periodicity, And Non-Normality, Nicholas W. Woolsey

Theses and Dissertations

Regression is a ubiquitous and fundamental method that can be found in any ele- mentary statistics course. The simplicity and self evidently useful nature of linear regression beguiles a non-negligible portion of researchers into disrespecting assump- tions required by these models, namely in terms of accuracy of covariates and the underlying nature of the data. This disregard can at best lead to meaningless results and at worse cause significant misunderstandings in scientific pursuit.

In this dissertation we strive propose remedies to violations of specific assump- tions. Namely the assumptions that covariates are either observed without measure- ment error or they …

Exploring The Ancestry And Mutational Signatures Of Free-Breeding Dogs From Chernobyl And The Galápagos Islands, Gabriella Jean Spatola

Theses and Dissertations

Two free-breeding dog populations, one in Chernobyl, Ukraine, and the other on the Galápagos Islands, Ecuador, exist on opposite sides of the globe, yet both hold unique scientific potential to further our understanding of free-breeding dog population dynamics and evolutionary processes related to their environments. In the following studies, blood samples from more than 400 individual Chernobyl dogs were collected and their genomes were analyzed alongside over 1500 purebred and 200 global free-breeding dogs, describing genetic relationships and the extent of admixture with purebred migrants. Importantly, the sampled Chernobyl dogs had long-term exposures to ionizing radiation because of the 1986 …

Inorganic Nanoparticle And Nanoplastic Transformations And The Impact On Biouptake By Freshwater Algal Cells Using Single Cell And Single Particle Inductively Coupled Plasma Mass Spectrometry, Elizabeth Carey Bair

Theses and Dissertations

The ubiquitous presence of nanoparticles (NPs) and nanoplastics (NPPs) and their effects on environmental and human health is a significant concern. They are used in every aspect of our lives, and while they offer many benefits, there are concerns about their impacts on ecosystems and human health. The primary aim of this dissertation is to quantify NP and NPP transformations in the presence of algae and determine how those transformations influence bioavailability. The methodology involves two complementary analytical techniques: single particle (SP) and single cell (SC) inductively coupled plasma mass spectrometry (ICP-MS). These techniques are tested and applied to two …

Birth Of Inspiration: York County, South Carolina, The Setting That Inspired The Clansman, Zachary Alan Lemhouse

Theses and Dissertations

In 1905, Thomas Dixon, Jr., published his controversial novel The Clansman. Monopolizing on racist sentiments held by white southerners, Dixon’s narrative contributed significantly to the perception of the Lost Cause myth and defense of white supremacy in America. The novel, and its subsequent adaptations as a play and the film Birth of a Nation, was inspired by actual events that occurred in Dixon’s ancestral home of York County, South Carolina. Located in the northernmost region of South Carolina’s Piedmont, York County played host to a struggle for civil rights during the Reconstruction Era that garnered national and international …

Aesthetic Judgment: Considering A Contemporary Standard Of Taste, Lydia Margaret Lee

Theses and Dissertations

Originally published in 1757 as part of his Four Dissertations essay collection, David Hume’s essay, “Of the Standard of Taste,” occupies a prominent place in Enlightenment aesthetic studies. Due to an oversaturation of print materials being produced, eighteenth century society was concerned with evaluating and ranking the massive quantities of art being produced. Philosophers such as David Hume attempted to define criteria for determining a standard of taste, aiming to hierarchically rank works of art based on aesthetic experience. For centuries, critics such as Timothy Costelloe, Noel Carroll, David Marshall, Jonathan Friday, James Shelley, and many others have engaged in …

Strain And Redox Engineering For Enhanced Thermoelectric Performance In Transition Metal Oxide Thin Films, Mohammad Jamal El Loubani

Theses and Dissertations

The discovery of highly efficient and cost-effective thermoelectric (TE) materials is essential to envision high-performance TE power generators that enable the direct conversion of waste heat into electricity. Transition metal oxides (TMOs) are considered promising candidates for high-temperature TE applications due to their excellent thermal stability and low cost. However, their maximum power output (power factor, PF = σ•S2) is constrained by the intrinsic trade-off between thermopower (S) and electrical conductivity (σ), both of which are inversely related to carrier concentration. This trade-off poses a significant barrier to improving the performance of TE devices. Among various strategies to overcome this …

Ideologies Of Language, Race, And Time In U.S. Political Discourses, Paige Pinkston

Theses and Dissertations

This dissertation follows how public discourses that emerged during the 2020- 2022 “Critical Race Theory Panic” played out in different contexts and at different scales in the United States, from conservative national media to South Carolina legislative action. While political discourse has become increasingly nationalized (Berry & Sobieraj, 2014), new legislation has largely taken place at the state level (Johnson, 2022). Drawing on over two years of fieldwork and methods of discourse analysis, I thus examine how nationally circulating discourses about race and racism were taken up by South Carolinians to create partisan alignments and distinctions as well as to …

Help-Seeking, Motivation, And Partner Interactions In Couples Affected By Tramatic Brain Injury, Violet Hodge

Theses and Dissertations

Traumatic brain injury (TBI) affects individuals and their romantic relationships, creating barriers to help-seeking and impacting relational health. Despite evidence supporting the benefits of couples counseling and relationship education, stigma and motivational factors influence engagement in these services. This dissertation examines the interdependent processes of help-seeking, motivation, and relationship satisfaction in couples where one partner has experienced a TBI. Using the Actor-Partner Interdependence Model (APIM), two studies explore (1) the role of self-stigma in help-seeking and motivation for completing a relationship education program, and (2) the influence of self-stigma for help-seeking on motivation in couples services, particularly in the context …

Autoregressive Modeling Of Dna Molecule Shapes Accompanied By An Empirical Assessment Of The Ljung-Box Test, David William Custer

Theses and Dissertations

The assumption of independence rarely holds in real-world data. Correlated observations are ubiquitous, especially in sequential contexts where time series models are essential for capturing temporal dependence. This study analyzed six groups of damaged and undamaged DNA sequences, where an "F" in the middle of a sequence indicates damage. One biological aim is to understand how DNA regenerates with the assistance of proteins that recognize damaged regions. Motivated by empirical support for AR(2) modeling, we fit autoregressive models to the first three principal component scores of each DNA group, capturing the dominant structure in the data. We conducted model diagnostics, …

Between Tajweed And Lenition: A Sociophonetic Investigation Of Pharyngealized Consonant Variation In Ammani Jordanian Arabic, Amenah Jehad Salman

Theses and Dissertations

Thіs dіssеrtаtіоn іnvеstіgаtеs the sосіоphоnеtіс vаrіаtіоn іn thе rеаlіzаtіоn оf phаryngeаlіzеd соnsоnаnts іn Аmmаnі Jоrdаnіаn Аrаbіс (АJА), іntrоduсіng Tаjwееd—thе study оf Qurаnіс phоnоlоgy—аs а sосіаlly sаlіеnt vаrіаblе іnfluеnсіng еvеrydаy spееch. А lеnіtеd-phаryngeаlіzеd (LP) vаrіаnt surfасеs аs аn аcоustіcаlly аnd pеrcеptuаlly іntеrmеdіаtе rеаlіzаtіоn, pоsіtіоnеd bеtwееn fully phаryngeаlіzеd (/sˤ, tˤ, dˤ, ðˤ/) аnd plаіn (/s, t, d, ð/) соnsоnаnts. Whіlе prеvіоus studіеs hаvе ехаmіnеd thе іmpасt оf mасrо-sосіаl fасtоrs suсh аs gеndеr, аgе, sосіоеcоnоmіс stаtus, аnd оrіgіnаl rеgіоnаl dіаlеct (ОRD) (Аl-Маsrі & Jоngmаn, 2004; Аlzоubі, 2017; Аbudаlbuh, 2010), nо rеsеаrch hаs examined thе rоlе оf Tаjwееd іn shаpіng sосіоphоnеtіс оutcоmеs.

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