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Loralee Clark, Loralee Clark, Loralee Clark

Virginia Poets Database: A Literary and Educational Resource

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Simulations Of Inverse Compton Scattering With Radiation Reaction, Elizabeth Breen-Lee

Physics Theses & Dissertations

Inverse Compton scattering (ICS) is a versatile mechanism for producing bright, tunable, and quasi-monochromatic x-ray and gamma-ray radiation through the interaction of relativistic electrons with intense laser pulses. These sources have applications spanning medicine, archaeological studies, materials science, and fundamental research, motivating continued efforts to improve both their performance and the accuracy of theoretical models used to describe them. As nextgeneration laser and accelerator facilities continue to reach increasingly intense regimes, efficient and accurate simulation techniques have become essential for the design and optimization of ICS sources. This dissertation presents the development of analytical and computational methods for modeling inverse …

A Phenomenological Study Of The Lived Mentoring Experiences Of Black Women Faculty At Public Hbcus, Leona Quatena Mcgowan

Educational Leadership & Workforce Development Theses & Dissertations

Despite increases in the representation of women in academia, Black women remain significantly underrepresented, accounting for approximately 4% of full-time faculty in postsecondary institutions. This lack of representation contributes to intersecting challenges, including experiences with racism, sexism, and limited access to mentorships in higher education. Previous studies have established that mentoring aids in the success and retention of faculty, but there is limited research examining how Black women faculty experience mentoring within public Historically Black Colleges and Universities (HBCUs). The purpose of this qualitative phenomenological study was to explore the lived mentoring experiences of Black women faculty employed at public …

Enhancing Stem Education With Modeling, Simulation, And Ai Technologies: From Virtual Laboratories To Intelligent Teaching Assistants, Yiyang Li

Electrical & Computer Engineering Theses & Dissertations

Rapid advancements in modeling and simulation (M&S) and artificial intelligence (AI) present new opportunities to enhance various aspects of STEM education, from virtual laboratories that simulate physical lab environments in software to intelligent teaching assistants that provide on-demand, curriculum-aligned instructional support. Virtual laboratories offer a potential solution to the access and scalability challenges of laboratory courses by allowing students to conduct experiments without physical equipment or geographical constraints. AI-powered teaching assistants, particularly those grounded in course-specific materials, can help mitigate the instructional support gap that arises when students work independently in digital learning environments. This dissertation presents three-phase research into …

Parameter Dependent Chen-Fliess Series And Their Nonrecursive Interconnections, Natalie T. Pham

Electrical & Computer Engineering Theses & Dissertations

In control theory, a Chen-Fliess functional series is a weighted sum of iterated integrals constructed from a given set of input functions. Such series can be used to represent nonlinear input-output systems. In applications, they have been employed to characterize interconnected nonlinear systems, to solve system inversion and tracking problems, and to design predictive and adaptive controllers.

Distributed parameter systems exhibit spatial dependence along with temporal dependence. Such systems are typically represented in terms of partial differential equations. In control theory, there appears to be no existing method for representing the input-output map of a distributed system via a Chen-Fliess …

Experimental Investigation Of The Discharge Modes Of Nanosecond Pulsed Plasmas At Atmospheric Pressure, Md Ziaur Rahman

Electrical & Computer Engineering Theses & Dissertations

The generation of repeatable and stable nanosecond pulsed atmospheric pressure plasmas is important to non-thermal plasma applications in various fields including medicine, material processing, food processing, and plasma ignition for combustion. This dissertation investigates the atmospheric pressure plasma initiation and formation under 10 – 200 ns pulsed power for electrode configurations applicable for transient plasma ignition (TPI) for combustion. The impacts of pulsed power parameters, gas condition, and electrode geometry on the discharge initiation and modes (i.e., streamer, transient spark and spark) are systematically evaluated for applying TPI for combustion. We evaluated the discharge modes driven by both longer and …

Effects Of Beverage Color During Mouth Rinsing On Measures Of Muscular Endurance, Muscular Strength, And Exercise Perceptions During Isometric Handgrip Testing, Sydney Andrews

Exercise Science Theses & Dissertations

Previous research has shown that color can influence psychological responses, physiological responses, and exercise performance. These effects have been previously attributed to learned associations or expectations which may influence exercise-related outcomes. This study aimed to investigate whether beverage color influences muscular performance during intermittent isometric handgrip exercise. This randomized, single-blind, deceptive crossover study consisted of 34 physically active adults (21.9±3.1 years) who completed a handgrip endurance test under three conditions: red beverage rinse, clear beverage rinse, and no-rinse. Participants were informed that the study would examine the effects of mouth rinsing two commercially available carbohydrate containing sport drinks on muscular …

A Qualitative Case Study Of Leadership Development In A Graduate Medical Laboratory Science Program, Demetra Castillo

EVMS School of Health Professions Theses & Dissertations

Leadership development is increasingly recognized as an essential component of healthcare education, particularly as medical laboratory professionals assume expanded responsibilities involving collaboration, decision-making, systems thinking, and organizational leadership. Despite this need, limited research has explored how leadership develops within graduate medical laboratory science (MLS) programs. This qualitative case study examined leadership development through the lens of Experiential Learning Theory (ELT). Two research questions explored how the program fostered leadership development through students’ professional biographies, leadership questionnaires, final reflection papers, and leadership credos and how leadership reflections demonstrated growth over time. Secondary data from five student cases were analyzed using deductive …

'We Will Be Here': Modeling Hunting Community Narratives In Avanersuaq, Greenland, Talor Stone

Graduate Program in International Studies Theses & Dissertations

The Inughuit, a small Indigenous population in Northwest Greenland with a rich history of subsistence hunting in one of Earth’s harshest environments, have long been portrayed in Western media and academic literature as symbols of vulnerability and resilience, often depicted more as icons of climate change and a culture under threat than as actual people with hopes and aspirations. Indigenous voices are strikingly absent from these Western accounts.

As the Arctic gains prominence amid rapid growth in climate discourse, regional geopolitics, and tourism, the implications of these representations become increasingly significant. When Western crisis narratives dominate discourse and shape regulatory …

Energy Transition In Africa: A Comparative Analysis Of Five African Countries, Boluwatife G. Ayankojo

Graduate Program in International Studies Theses & Dissertations

Global energy transition remains a critical challenge for reducing carbon emissions and protecting the environment, with solar energy adoption driving improvements in both energy efficiency and conservation. This research focuses on Africa's transition from fossil fuels to solar energy. As population growth and blackouts increase, African countries must transition from unreliable, centralized national grids to decentralized, low-carbon alternatives that ensure quality household electricity. While some countries have advanced in this transition to sustainable solar energy, others lag behind. The limited access to electricity hinders the African continent's healthcare, education, economic growth, and mortality rates. This research establishes the importance of …

Proxy Interfaces For Enhancing Non-Visual Web Usability, Md Javedul Ferdous

Computer Science Theses & Dissertations

People with blindness or visual impairments (BVI) face significant barriers when navigating the web, even when digital content is technically accessible. These challenges arise not from a lack of access, but from a mismatch between vision-centric user interfaces and the linear, audio-based interaction paradigms of screen readers. Sighted users rely on spatial layout, grouping, and visual cues to interpret structure quickly, while blind users must explore elements sequentially, often without sufficient context. As a result, they expend greater cognitive effort, become disoriented more easily, and struggle with tasks that are usually trivial for sighted users. Although accessibility initiatives have focused …

Macroscopic Classical And Quantum Models Of Inverse Compton Scattering, Emerson Penn Rogers

Physics Theses & Dissertations

Inverse Compton sources — in which a relativistic electron beam scatters a laser pulse to produce tunable, collimated, high-energy radiation—have emerged as among the most promising compact radiation sources, with applications ranging from nuclear photonics to medical and nanoscale imaging and metrology. The most viable current tabletop configuration couples laser-wakefield acceleration with inverse Compton scattering, producing GeV-scale electron beams over millimeter distances. As laser intensities increase and electron energies grow, the interaction enters the radiation reaction regime, where the energy radiated by the electron becomes a significant fraction of its kinetic energy. Predicting the scattered electron energy spectrum — the …

Extinction Risk Of Coral Reef Fishes In The Philippine Marine Ornamental Trade, Jemelyn Grace Baldisimo Sepulveda

Biological Sciences Theses & Dissertations

Coral reef ecosystems in the Philippines face severe threats from intense fishing and habitat degradation. This dissertation evaluated the extinction risk of fishes in the Philippine Marine Aquarium Trade (MAT) using Productivity Susceptibility Analysis (PSA) and temporal genomics. A global PSA framework was modified by including local susceptibility factors. Of the 103 species evaluated, six were categorized as highly vulnerable and 62 as moderately vulnerable, revealing increased local vulnerability and underscoring the importance of local assessments to guide conservation efforts.

Temporal genomics compared historical (1908–1909 U.S.S. Albatross Expedition) and contemporary populations of the MAT-targeted Sphaeramia nematoptera and Pseudanthias squamipinnis, …

Interpretable Sparse Modeling Of Longitudinal Signals Via Critical-Range Rectification And Anytime Rule Compression, Jason Orender

Computer Science Theses & Dissertations

High-dimensional longitudinal data arise in clinical monitoring, industrial control systems, and other sensor-driven domains where outcomes are often governed by threshold-and-lag behavior. Traditional longitudinal workflows frequently depend on expert guessing to nominate candidate variables, lag windows, and threshold hypotheses, followed by repeated hypothesis testing over a limited set of manually specified relationships. While such approaches can be useful in narrow settings, they are often less robust in high-dimensional regimes because important interactions may be missed, multicollinearity can destabilize inference, and the resulting process can be labor-intensive and difficult to scale. This dissertation develops an end-to-end framework for interpretable sparse longitudinal …

Towards More Realistic And Practical Graph Backdoor Attacks, Jiawei Chen

Computer Science Theses & Dissertations

Graph Neural Networks (GNNs) have demonstrated remarkable performance on graph-based learning tasks and are increasingly deployed in security-critical applications. However, recent studies have shown that they are highly vulnerable to graph backdoor attacks (GBAs), where adversaries implant malicious triggers to induce targeted misclassification during inference. Despite their effectiveness, existing GBAs are often developed under unrealistic assumptions, such as focusing exclusively on simple homogeneous graphs or assuming the adversary possesses privileged access to target nodes during inference. This dissertation aims to systematically investigate and design graph backdoor attacks under significantly more realistic graph settings and adversarial constraints.

First, we investigate the …

Atomic-Scale Investigation Of Functional Molecular Systems And Graphene Nanoribbons Using Scanning Probe Microscopy, A.M. Shashika D. Wijerathna

Physics Theses & Dissertations

Emerging molecular electronics, molecular devices, and carbon-based nanotechnologies increasingly rely on the precise control of molecular structures and interfaces at the atomic scale. Advancing these systems requires experimental techniques capable of resolving atomic structures, quantifying molecular behavior, and revealing the mechanisms governing nanoscale assembly. Scanning probe microscopy uniquely provides these capabilities by combining atomic-resolution imaging with local spectroscopy and manipulation. This dissertation employs ultra-high-vacuum low-temperature scanning tunneling microscopy (UHV-LT-STM) and qPlus atomic force microscopy (qPlus AFM) to address three complementary challenges: (i) atomic-scale characterization of complex supramolecular architectures, (ii) quantitative investigation of mechanically induced conformational switching of individual molecules, and …

Drones In Wildfire Airspace Management: Developing A Scalable Framework For Mid-Sized Cities, Victoria Denise Tanner Williamson

Engineering Management & Systems Engineering Theses & Dissertations

Wildfires are becoming increasingly frequent and severe, creating growing risks for mid-sized communities with limited emergency response resources. The January 2025 Los Angeles wildfires—which burned more than 57,000 acres and destroyed over 18,000 structures—underscore the urgent need to strengthen wildfire response strategies through the integration of unmanned aerial systems (UAS) (Hardy, 2025).

This study develops a scalable framework for drone-assisted wildfire response in resource-constrained environments. Using the city of Waynesboro, Virginia, as a case study, the research examines how mid-sized jurisdictions can integrate unmanned aerial vehicles (UAVs) to improve preparedness, response, and recovery. A three-round, mixed-methods Delphi study engages emergency …

Nanostructured Negative Electron Affinity Gallium Arsenide Photocathodes With Enhanced Quantum Efficiency And Extended Charge Lifetime For Advanced Photoinjectors, Md Aziz Ar Rahman

Physics Theses & Dissertations

This dissertation presents a comprehensive experimental and computational investigation of nanostructured negative electron affinity (NEA) gallium arsenide (GaAs) photocathodes. This work was undertaken to achieve higher quantum efficiency (QE) and longer charge lifetime than conventional flat NEA GaAs electron sources commonly used in photoinjectors. Finite-Difference Time-Domain and charge-transport simulations of three types of nanostructure geometries reveal substantial QE enhancement over flat GaAs via Mie resonance mode excitation. Consequently, the truncated nanocone array (TNCA) photocathodes with heights of 400, 700, and 1000 nm were fabricated and NEA activated via Cs-NF₃ deposition. In a low-voltage ultra-high vacuum chamber with a base pressure …

Technical And Vocational High School Training And Graduates' Socioeconomic Insertion In Burkina Faso, Jacqueline Nikièma

Educational Leadership & Workforce Development Theses & Dissertations

Technical and vocational education and training (TVET) is widely promoted as a pathway to improving employment opportunities, supporting economic growth, and facilitating successful labor market transition. However, empirical evidence on its effectiveness remains limited in Burkina Faso. This study examined the relationship between TVET high schools and graduates’ socioeconomic insertion, with particular emphasis on employment in occupations related to the field of study (horizontal match) and examined the relationship between gender and this employment outcome. The study used descriptive statistics to summarize the characteristics of the sample, and logistic regressions to analyze the relationship between TVET training and employment in …

Analyzing The Institutional Factors Associated With Sense Of Belonging Among Stem Adjuncts At Community Colleges, Karuna Taneja

Educational Leadership & Workforce Development Theses & Dissertations

In this study I examined the relationships among organizational support, workplace conditions, and sense of belonging among adjunct faculty teaching STEM courses in community colleges. Grounded in the need-to-belong theory (Baumeister & Leary, 1995) and Herzberg’s two-factor theory (1968), I distinguished between relational and structural dimensions of faculty experiences. Perceived organizational support was conceptualized as a relational construct reflecting faculty members’ perceptions of being valued and included within their institutions, whereas workplace conditions were examined as structural factors influencing job satisfaction.

Using a quantitative, cross-sectional correlational survey design, data were collected from adjunct STEM faculty (N = 64) teaching at …

Modeling And Generating Crash Avoidance Behaviors In Safety-Critical Vehicle–Pedestrian Interactions Using Deep Reinforcement Learning, Qingwen Pu

Civil & Environmental Engineering Theses & Dissertations

Traffic crashes between vehicles and pedestrians arise from complex, split-second interactions in which both parties make rapid evasive decisions. Four fundamental gaps persist in existing research. Surrogate safety measures assume linear trajectories, failing to capture the curved movements of turning vehicles and crossing pedestrians at intersections. Single-agent modeling treats one party as a fixed obstacle, ignoring the joint decision-making that governs near-miss outcomes. The effect of vehicle type on pedestrian avoidance behavior—whether pedestrians respond differently to automated vehicles (AVs) than to human-driven vehicles (HDVs)—remains poorly understood. Finally, automated driving system development is hampered by a severe scarcity of large-scale, behaviorally …

Structure Meets Context: A Simulation Study Of Centralized And Decentralized Decision-Making In Complex Environments, Murat Balci

Engineering Management & Systems Engineering Theses & Dissertations

The question of when to centralize or decentralize decision-making authority is a foundational problem in organizational theory and management science. Yet existing research often favors decentralized structures, frequently treating them as universally superior, and provides limited guidance on when centralization may be more effective. Leaning toward decentralization without thoroughly exploring options leaves organizational designers without clear direction under varying environmental conditions. This study addresses that gap by developing and applying a simulation-based framework to evaluate the context-dependent effectiveness of centralized and decentralized decision-making structures.

Drawing on contingency theory and decision science, the study conceptualizes environmental complexity along two dimensions: dynamism …

Empirical Rhetorical Modeling: New Analytical Tools To Evaluate The Intensity Of Rhetoric, August Immel

English Theses & Dissertations

Since 2020, the United States has experienced a surge of incendiary rhetoric in contemporary political discourse, which exacerbates societal polarization and incites violence as evidenced by heightened politically motivated attacks. Numerous actors characterize the impetus of such violence as “extreme rhetoric.” No standard definition exists for such a term, and this gap necessitates the central research question of this dissertation, which interrogates how rhetoric can be systematically evaluated for “extremeness.” I propose that the issue of extreme rhetoric can be fruitfully examined from within the context of rhetorical theory, but instead of attempting to create a new definition of “extreme …

Physics-Guided Deep Learning For Predictive Modeling Of Spatiotemporal Dynamical Systems, Niharika Deshpande

Engineering Management & Systems Engineering Theses & Dissertations

Many physical and networked systems evolve under continuously changing spatial and temporal conditions. Transportation networks respond to fluctuating demand, atmospheric fields reorganize as storms intensify, and coastal response depends on localized forcing pathways. Modeling such systems requires learning formulations that adapt to evolving structure, operate on irregular geometries, and provide interpretable measures of predictive uncertainty. This dissertation develops a physics-guided spatiotemporal learning framework designed for structured dynamical systems whose governing interactions are neither static nor Euclidean. The central premise is that spatial relationships in these systems are dynamic and geometry-dependent. To represent this behavior, system states are modeled on time-varying …

A Causal Inference Protocol For Root-Cause Diagnosis In Non-Stationary Industrial Time Series, Cansu Yalim

Engineering Management & Systems Engineering Theses & Dissertations

Industrial fault diagnosis increasingly relies on data-driven methods, yet most approaches assume process stationarity and treat association-based rankings as sufficient evidence for root-cause identification. Neither assumption holds when operating phases and fault progression create distinct behavioral regimes with shifting relationships among variables, and neither answers which feasible corrective action would alter a fault trajectory. The absence of a procedure addressing non-stationarity, causal identifiability, and decision-relevant effect estimation constitutes the gap this dissertation targets. In this context, a regime is a time period in which the process operates under a relatively consistent setting, so the relationships among variables are approximately stable …

Quantitative Surface-Enhanced Raman Spectroscopy For Antiretroviral Drug Monitoring: Novel Quality Index And Distributional Approaches In Aqueous And Plasma Matrices, Marguerite Rose Butler

Chemistry & Biochemistry Theses & Dissertations

Surface-enhanced Raman spectroscopy (SERS) offers high sensitivity for molecular detection but is limited for quantitative applications by spatial heterogeneity in signal enhancement on dried colloidal substrates. This Dissertation addresses these limitations through the development and evaluation of novel quantitative methods applied to the antiretroviral drugs tenofovir and emtricitabine.

A quality index (Qi) metric was developed to rank individual SERS spectra within each well based on analyte peak prominence relative to local baseline. SERS spectra were acquired from evaporated silver colloid deposits on aluminum well plates using a custom raster-scanning Raman system. Calibration curves were constructed using the top-ranked spectra (Top-Qi …

Computational And Ai Tools For Understanding Telomere-Associated Cancer Mechanisms, Eleni Adam

Computer Science Theses & Dissertations

Telomeres are the protective caps of the human chromosomes and are critical for genome stability. Dysfunctional telomeres caused by their erosion with age and cell proliferation as well as by defects in their maintenance is a major early event leading to genome changes and cancer. Subtelomeres possess the critical role of regulating adjacent telomeres. Due to their complex repeat structure and high variance from one person to another, these areas have not been analyzed in detail. We present a set of computational and machine learning tools to aid in the understanding of subtelomere structure and its rearrangements in cancer.

Initially, …

Public Participation In Community Redevelopment Agencies: A Mixed Methods Approach To Understanding The Impacts Of Collaboration In Public-Private Partnerships, Shannon Mcbride-Lewis

School of Public Service Theses & Dissertations

Local governments create community redevelopment agencies (CRAs) to enhance economic and redevelopment opportunities within their communities through public-private partnerships funded with tax increment financing (TIF). The use of increment revenue, the complexity of public-private partnerships, and the controversies surrounding CRAs can lead to community concerns and opposition. Collaboratively engaging the public in the development, implementation, and performance of CRA public-private partnerships is one way to improve program and project outcomes by enhancing engagement, equity, and accountability. This study asks does the level of resources (dedicated professional staff, consequential incentives, and TIF contribution) and formal public-private partnership programs of CRAs influence …

Residual Stress Informed Reconstruction And Failure Analysis Of Manufacturing Induced Composite Meso-Structure, Mohammad Nazmus Saquib

Mechanical & Aerospace Engineering Theses & Dissertations

A physics informed, AI-augmented framework is developed to enable digital twins of molded composite materials by linking manufacturing induced residual stresses to a local meso-structure. By reconstructing and explicitly modeling these architectures, the framework reveals how processing driven meso-structural variability governs stiffness, damage evolution, and failure. The work focuses on two technologically important systems: prepreg platelet molded composites (PPMC), characterized by inherently stochastic platelet architectures, and 2/2 twill glass fiber/PA6 organosheets, whose periodic but locally variable weave geometry influences mechanical response. For PPMC, the Residual Stress Informed Microstructure Reconstruction (ResIMiR) framework is introduced, combining thermoelastic strain fields with deep learning …

Time-Frequency Analysis Of Arterial Pulse Signals Of Cardiovascular Disease Patients Measured By A Microfluidic-Based Tactile Sensor, Md Mahfuzur Rahman

Mechanical & Aerospace Engineering Theses & Dissertations

This dissertation presents a single-degree-of-freedom (SDOF) based time–frequency analysis framework that can simultaneously extract a comprehensive set of cardiovascular autonomic indices from arterial pulse wave recordings obtained at rest and post-exercise, supporting non-invasive monitoring of autonomic recovery during cardiac rehabilitation. The framework rests on three technical contributions.

First, an SDOF analytical model of motion artefacts quantifies two physically distinct distortion mechanisms: additive baseline drift and Time-Varying System Parameter (TVSP) generated distortion of the Tissue-Contact-Sensor (TCS) stack. Baseline drift is slowly varying and removable by filtering; TVSP distortion rides on all harmonics of the true pulse signal and cannot be removed …