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Convergence Estimate Of Minimal Residual Methods And Random Sketching Of Krylov Subspace Methods, Peter Westerbaan

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This study concerns two main issues in numerical linear algebra: convergence estimate of minimal residual methods based on explicit construction of approximate min-max polynomials for in- definite matrices, and development and analysis of Krylov subspace methods using non-orthonormal basis vectors based on random sketching. For a matrix A with spectrum Λ(A), it is well known that the min-max polynomial problem min max |pk (z)| pk ∈Pk, pk (0)=1, z∈Λ(A) is used to bound the relative error of Krylov subspace minimum residual methods or similar methods. For a symmetric positive definite matrix A, the min-max polynomial for the Conjugate Gradient (CG) …

“How Are High School Counselors Prioritizing The Information Relevant To Stem Career Preparation In Their Communication With Stem-Interested African American Students?”, Wysheka Austin

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Although African Americans and other minoritized groups have gradually increased in the number of students graduating with a Science, Technology, Engineering, and Mathematics (STEM) degree over the years, these groups remain underrepresented in STEM. Among the many factors contributing to the lack of representation is “college readiness,” which includes academic preparation and awareness of the necessary steps needed for college admission and career preparation [5]. South Carolina policy only considers academic preparation in their assessment of college readiness. To measure academic preparation of any student, the state relies on standardized test scores and advanced course taking without regard to subject. …

A Mixed Methods Study Of South Carolina Reading Policy On Teacher Knowledge, Matthew Ferguson

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This sequential explanatory mixed methods study examines the impact of the Language Essentials for Teachers of Reading and Spelling (LETRS) professional learning intervention on teacher knowledge within the context of South Carolina's reading policy.

Quantitative analyses of pre- and post-assessment data indicate significant improvements in teacher content knowledge of foundational literacy skills following LETRS training. Descriptive statistics and paired-samples t-tests demonstrate substantial gains in knowledge, particularly in Volume 1 of the LETRS curriculum. The study reveals notable increases in pre- and post-assessment scores, suggesting the effectiveness of LETRS in enhancing teacher expertise.

Qualitative findings from focus groups highlight the positive …

Time Resolved X-Ray Spectroscopy Of Highly Charged Ar, Nd, And Pr, Timothy Burke

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Highly Charged Ions (HCIs) may be considered ideal mini-laboratory in which one can study the physics of matter and light in an environment of high internal electric field that can not be recreated with standard lab equipment. The remaining electron(s) exist in the extremely large electric field of the nucleus and therefore measurements of electronic transitions in these systems provide stringent tests of our understanding of physics in extreme conditions. Quantum electrodynamics (QED) despite being a powerful theory exhibits large discrepancies for systems under extreme conditions. The work here investigates the atomic properties within non-Maxwellian plasmas. The HCI plasmas studied …

What Do You Want To Be When You Grow Up? An Explanatory Sequential Mixed Methods Study Examining What Influential Factors Guide Rural Middle School Students To Consider A Potential Career Trajectory, Heather Wilks

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This explanatory sequential mixed methods study examines what influences 7th and 8th grade rural middle school students to consider a potential career trajectory. Phase One of the study includes a demographic and career cluster interest survey of 38 participants. Phase Two of the study focused on 23 of the 38 Phase One participants, who were chosen using random sampling. The Phase Two participants were interviewed using a semi-structured approach. They were asked to discuss their career cluster results from Phase One, how they used their surrounding factors and knowledge to conclude, and if they agreed with their results. Findings indicated …

Development And Application Of Discrete Element Models For Granular Materials - From Rigid Spheres To Complex-Shaped Flexible Particles With Breakage, Zakia Tasnim

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Granular materials, which can range from nanometers to centimeters, are widely encountered as particles or powders in nature and in engineered systems. Some examples of granular materials include sands, gravels, biomass feedstocks, rice grains, pharmaceutical pills, glass beads, and lunar or martian regolith simulants. The attributes of and the interactions between constituent particles dictate the bulk mechanical properties and behavior of granular materials. The discrete element method (DEM), a particle-based modeling technique, has become a useful numerical tool for modeling the bulk behavior (such as mechanical, flow, and breakage behavior) of granular materials, where interactions between the granular materials' individual …

An Exploration Of The Efficacy Of Virtual Agents Within Smartphone Mental Health Applications, Stephanie Six

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The prevalence of depression in the U.S. has increased over the past decade, leading to an all-time-high during the COVID-19 pandemic (WHO, 2022). With this increase, the number of mental health applications (MHealth apps) on virtual e-stores increases in tandem. Despite this expanding number of MHealth apps, few demonstrate a foundation in empirical research. One design factor that may influence usability and effectiveness is the inclusion of virtual agents. Three studies were conducted to investigate users’ preferences for a variety of characteristics associated with virtual agents. In Experiment 1, users completed a single-session, three-stage CBT-based interaction with virtual characters and …

Understanding The Experiences Of Para-Collegiate Student- Athletes: A Mixed Methods Study, Derek Whaley

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Experiences are the impressions developed through gaining, using, fostering, and sometimes disposing of a service or product. Recent years have shown an ongoing emphasis placed on experiences and their impacts; one of particular interest for this study are the experiences of para-collegiate student-athletes. Using the Experience Type Framework (ETF) and the Extraordinary Impact Scale (EIS), the purpose of this study was to understand the experience of involvement in intercollegiate sports among adaptive student-athletes. This study employed an explanatory sequential mixed methods design, using quantitative and qualitative data to understand the adaptive student-athlete experience. Phase I (n = 30) used the …

Shift Schedule Justice And Clinician Outcomes: A Quasi-Experimental Approach, Caroline George

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Emergency Physicians (EPs) work in stressful and unpredictable work environments. Due to these factors and the nature of their work scheduling (in shifts), EPs experience heightened levels of adverse work outcomes. As such, it is important for EPs to believe their shift schedule is fair, and for them to have adequate recovery time away from work. The present research examined the effects of Emergency Department leadership approving a 1-hour increase to EP shifts, equating to roughly two fewer shifts per month (8-hour shifts will become 9-hour shifts). As such, EPs should experience more time off from work per month, allowing …

Evacuation Of Students With Intellectual Disability In Building Fires: A Three-Part Methodology, Haley Hostetter

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People with disabilities are one of the most vulnerable groups in building fires. Despite this, they have traditionally been overlooked by fire evacuation researchers. This is perhaps the most alarming for the group with Intellectual Disability when given their present statistics for fire involvement, injuries, and death. Annually, people with mental disabilities are involved in 1700 home fires, resulting in 39 fatalities and 122 injuries per 1000 fires. Additionally, 40% of these fires were started intentionally by people with mental disabilities. When combined with their high fire risk, the lack of evacuation research focused on people with Intellectual Disability shows …

Real-Time Degradation Abatement Framework For Energy Storage System In Automotive Application Using Data-Driven Approaches, Laxman Timilsina

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The increasing popularity of electric vehicles (EVs) is driven by their compatibility with sustainable energy goals. However, the decline in the performance of energy storage systems, such as batteries, due to their degradation puts EVs and hybrid electric vehicles (HEVs) at a disadvantage compared to traditional internal combustion engine (ICE) vehicles. The batteries used in these vehicles have limited life. The degradation of the battery is accelerated by the operating conditions of the vehicle, which further reduces its life and increases the reliability and economic concerns for the vehicle’s operation. The aging mechanism inside a battery cannot be eliminated but …

Domain Decomposition Methods For Fluid-Structure Interaction Problems Involving Elastic, Porous, Or Poroelastic Structures, Hemanta Kunwar

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We introduce two global-in-time domain decomposition methods, namely the Steklov-Poincare method and Schwarz waveform relaxation (SWR) method using Robin transmission conditions (or the Robin method), for solving fluid-structure interaction systems involving elastic, porous, or poroelastic structure. These methods allow us to formulate the coupled system as a space-time interface problem and apply iterative algorithms directly to the evolutionary problem. Each time-dependent fluid and the structure subdomain problem is solved independently, which enables the use of different time discretization schemes and time step sizes in the subsystems. This leads to an efficient way of simulating time-dependent multiphysics phenomena. For the fluid-porous …

Inviting The Public Into Wildlife Research: Does Participation In Research Projects That Facilitate Interactions With Local Species Change Feelings Of Connection?, Seth Gibbons

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For many reasons, humans are less connected to nature. Research shows that people who feel more connected to nature are more likely to have pro-environmental intentions. One possible way to strengthen the human-nature connection is to involve the public in wildlife research, exposing them to local wildlife in a way that highlights science. This dissertation investigates two such projects, the 2019 Clemson Barred Owl Project and the Trout in the Classroom (TIC) program, to understand the effects of interacting with local species through wildlife research.

Interviews were conducted with participants and the lead researcher of the Clemson Barred Owl Project …

Design, Fabrication, And Characterization Of Advanced High-Power Single-Mode 9xxnm Semiconductor Lasers, Xiaolei Zhao

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This thesis presents the comprehensive design, fabrication, and demonstration of advanced high-power, high-efficiency single-mode semiconductor lasers operating at a wavelength of 9xxnm. We begin with the design of the laser epitaxial structure, serving as the cornerstone for achieving high-power high-efficiency lasers. Our methodology integrates a semi-analytical calculation model, which accounts for Longitudinal Spatial Hole Burning (LSHB) and Two-Photon Absorption (TPA) effects, facilitating a thorough exploration of how design parameters influence output power and conversion efficiency. This approach offers an effective and time-efficient epitaxial structure optimization strategy compared to conventional full 3D simulation models.

Subsequently, we demonstrate high-power, high-efficiency ridge waveguide …

Robust And Trustworthy Deep Learning: Attacks, Defenses And Designs, Bingyin Zhao

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Deep neural networks (DNNs) have achieved unprecedented success in many fields. However, robustness and trustworthiness have become emerging concerns since DNNs are vulnerable to various attacks and susceptible to data distributional shifts. Attacks such as data poisoning and out-of-distribution scenarios such as natural corruption significantly undermine the performance and robustness of DNNs in model training and inference and impose uncertainty and insecurity on the deployment in real-world applications. Thus, it is crucial to investigate threats and challenges against deep neural networks, develop corresponding countermeasures, and dig into design tactics to secure their safety and reliability. The works investigated in this …

Can I Get A Witness? Employee Reactions To Witnessing Visible Self-Compassion At Work, Sara Krivacek

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Self-compassion is defined as a tripartite process whereby an individual notices their own suffering, feels empathetic concern for oneself, and responds to alleviate or address the suffering. Research on self-compassion has proliferated in the last decade, and a major theme in the literature posits that it is beneficial for the practicing individual. However, less attention is given to the impact of self-compassion expression on other individuals in the workplace – partly because one major assumption is that self-compassion is an internalized process. In this dissertation, I conceptualize self-compassion as a social process and draw from affective events theory to make …

Essays On Environmental And Natural Resource Economics, Annaliese R. Winton

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This dissertation explores how markets and producers respond to environmental risks that are becoming more severe due to climate change. It is comprised of two essays that empirically quantify the economic impacts of two water-related risks: storm surge flooding and groundwater depletion. In the first chapter, I estimate the price differentials associated with single-family homes in hurricane evacuation zones in Miami-Dade County, Florida, using two near-miss hurricanes as a source of exogenous information. The second chapter estimates the impacts of groundwater depletion, as captured through declining well capacity, on irrigation decisions in the Colorado portion of the Republican River Basin.

Structure And Dynamics Of Complex Fluids Formed By Ionomers: Experimental-Computational Insight, Chathurika Kosgallana

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The current study focuses on understanding the effect of clustering on the structure, dynamics, and response of ionomers in melts and solutions using neutron scattering methods combined with atomistic large-scale molecular dynamics (MD) simulations.

Ionizable polymers are used in a wide range of applications, such as in clean energy and biotechnology, where ion transport is integral to the application. Ionizable groups drive cluster formation and often become the dominating force in determining the structure and dynamics of these polymers.

The work consists of five studies. The first study probes the structure of sulfonated polystyrene in toluene solutions tweaked by the …

Essays On The Labor Market Outcomes And Location Choices Of Military Veterans, Brian Bifulco

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The economic outcomes of military veterans are a persistent source of interest for economists, policy analysts, and the public in the United States. Veterans' outcomes bear directly on the decision of prospective recruits to join the military and current service-members to exit the military, informing policymakers about the long-term sustainability of the all-volunteer force. This dissertation focuses on veterans' economic outcomes by examining their relationship with market entry conditions and the location decisions veterans make when they exit the military.

Chapter 1 examines the earnings and employment outcomes of new military veterans associated with market entry conditions. This chapter intersects …

Going, Going, Gone: The Influence Of Job And Home Demands And Resources On Emergency Department Nurse Turnover, Jordan Gail Smith

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Nurse turnover, which challenged healthcare organizations even before the pandemic, reached alarming rates across hospitals worldwide during COVID-19. Due to the unprecedented and stressful nature of the pandemic, recent investigations have focused primarily on exploring job demands and nurse turnover intentions. While job demands are critical to understanding turnover, this narrow scope ignores the possible influence of other factors such as job resources and demands and resources external to the work domain. This study utilized archival qualitative data from a longitudinal survey of Emergency Department clinicians to analyze research questions and hypotheses. The first aim of this study was to …

Students Willing And Ready To Motivate To Graduate: An Alternative Pathway To Graduation, Laura Lusk

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With the continual decline of high school graduation rates in South Carolina, there is a need for high schools to look at alternative pathways to graduation. Many of the current alternatives offered to students remove them from the high school setting or interactions with the student body. This study focused on an alternative pathway to graduation, Students Willing and Ready to Motivate to Graduate (SWARM), offered at the high school during the regular school day to students in jeopardy of not graduating. This inclusive approach eliminated transportation barriers and access issues. Students attended school regularly, but one to four classes …

Restoring Student Behavior: A Culturally Responsive Evaluation Of Restorative Practices On Disproportionate Referral Data, Meredith Strmac

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Male students of color often receive harsher disciplinary consequences than their same age White peers. Disproportionate discipline practices have existed within the education system for years, primarily due to a historical systemic issue of implicit bias due to race. One intervention used to quell some of these disparities is Restorative Practices. This program evaluation study used Restorative Practices as an intervention to determine the extent that it could close the discipline gap in one South Carolina high school. Using a concurrent nested mixed method design, I analyzed and synthesized historical agency data to answer the first research question regarding the …

Equipping Educational Leaders To Lead Data Democracies: A Case Study, Diane Sigmon

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Educational policy, technology, and data now converge to establish a new educational leadership concept, data democracies. The movement away from a few technically skilled staff as gatekeepers of all things data is quickly accelerating. The emergence of data democracies represents a significant paradigm shift in education, necessitating a corresponding response from educational leaders and their training systems. Leaders must possess high data literacy to effectively interact with data and derive meaningful insights. Additionally, systemic changes are required to foster a cultural shift towards viewing data as a tool for growth rather than punishment. However, the existing body of research in …

Ecology And Integrated Pest Management Of Major Insect Pests Of Field Corn, Tim Bryant

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In the southeastern United States, the brown stink bug, Euschistus servus (Say), and the southern green stink bug, Nezara viridula (L.) (Hemiptera: Pentatomidae), are common economic pests of corn, Zea mays L. (Poaceae: Poales). Although commonly found, the corn earworm, Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae), is generally not an economic pest and is managed with transgenic corn hybrids expressing toxins produced by the Bacillus thuringiensis (Bt). Resistance to Bt toxins is a major thread to the sustainability of Bt crops. Understanding the ecology of stink bugs and corn earworms in field corn can help to effectively implement integrated pest management …

Examining Policy Diffusion Mechanisms In The Contemporary Local Government Landscape Of A Politically Polarized United States, Jacob Mccauley

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This dissertation explores the nuanced relationship between political polarization and policy diffusion within local governments in the United States, a topic of considerable relevance given the country’s increasing political divide. By examining the diffusion of COVID-19 policies, historical marker modifications, and the implementation of eGovernment services, this research identifies a novel mechanism of policy diffusion that is significantly influenced by political party lines. The study employs a comprehensive methodological approach, incorporating case studies and quantitative analysis to examine policy implementation across politically diverse local governments. The findings reveal that political affiliation profoundly impacts policy choices, with distinct patterns of policy …

Applications Of Conic Programming Reformulations, Sarah Kelly

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In general, convex programs have nicer properties than nonconvex programs. Notably, in a convex program, every locally optimal solution is also globally optimal. For this reason, there is interest in finding convex reformulations of nonconvex programs. These reformulation often come in the form of a conic program. For example, nonconvex quadratically-constrained quadratic programs (QCQPs) are often relaxed to semidefinite programs (SDPs) and then tightened with valid inequalities. This dissertation gives a few different problems of interest and shows how conic reformulations can be usefully applied.

In one chapter, we consider two variants of the trust-region subproblem. For each of these …

Intrinsically Disordered Proteins And Their Role In Biomolecular Condensates, Danielle Latham

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Proteins are biomacromolecules responsible for the functions of life. While classically proteins are thought to be well structured in order to perform a specific function, 50% of proteins within Eukaryotic cells contain intrinsically disordered regions (IDRs), regions with no well-defined structure. IDRs are often used for cell signaling, responding to external factors such as temperature changes or the presence of small molecules. To understand how IDRs can function without structure, it is important to understand the dynamics of such systems. Understanding IDR intramolecular and intermolecular interactions will shed light on IDR dynamics. Intramolecular interactions are first explored using fluorescence spectroscopy …

Release Of Small Molecules From Rubber: Effects Of Materials Properties, Mechanical Loading And Molecular Interactions, Yongcan Du

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Release of small molecules from polymeric materials has wide applications in the delivery systems of active molecules such as drug, fragrance, and semiochemical. Rubber materials are good candidates for the excipients of those systems due to properties such as good flexibility, permeability, and biocompatibility. Factors like material properties, mechanical loading, and molecular interactions may affect the release of small molecules in those systems. Therefore, understanding how those factors affect the release is key to the formulation, design, and evaluation of those systems.

To study the effects of materials properties, vulcanized natural rubber sheets with different crosslink densities, loaded with small …

A Comprehensive Materials Approach To Thermal Management In Fiber Lasers, Bailey Meehan

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Optical fiber-based amplifiers and lasers enable a great many useful devices and conveniences. Unfortunately, however, they can generate considerable heat during operation that drives the need for complex cooling solutions, thus reducing many of the size, weight, and power (SWAP) benefits for which fiber lasers are known. Additionally, at elevated temperatures, thermally-driven phenomena, such as Transverse Mode Instability (TMI), can be induced that limit the power-scaling of fiber lasers. The focus of this Dissertation is to explore novel approaches to thermal management in fiber lasers through judicious materials science and engineering to obviate the aforementioned limitations. Fibers studied in this …

Policy Solutions For Juvenile Cyber-Deviant Behaviors: Insights From Criminological Theory, Holly Verity Williams

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The aim of this thesis is to develop a deeper understanding of online deviance as a phenomenon among juveniles, both in terms of engagement and victimization, by applying Attachment Theory, Social Learning Theory, and Self-Control Theory. Throughout the literature, Attachment Theory, Social Learning Theory, and Self-Control Theory have been attributed as key criminological theories in the explanation of juvenile deviance offline, but little research has been applied to online deviance in this way. This thesis seeks to apply the same criminological theories to the phenomenon of online deviance among juveniles and compare outcomes to both online and offline deviance among …