Digital Commons Network^™

Dynamics Of Household Food Insecurity Vulnerability: Examining Health, Functional Limitations, And Income Stability, Renita Washburn

Graduate Studies Theses and Dissertations 2026

Household food insecurity is a multidimensional issue affecting millions of households in the United States. While research has established that low income and poor health or functional limitations can increase the risk of food insecurity, current approaches do not fully capture these dynamic processes to identify long-term vulnerability. Specifically, income-based measures rely on static thresholds that miss instability, potentially underestimating risk. Gaps also remain in understanding persistent food insecurity, including how functional limitations (difficulties with activities like bathing, shopping, or managing finances) are associated with insecurity over time. These functional limitations can impact both economic factors (such as the ability …

The Effects Of Episodic Facilitation And Immersion On Memory Formation During Learning Of An Exterior Preflight Inspection Procedure, Nathan A. Sonnenfeld

Graduate Studies Theses and Dissertations 2026

This research examined the use of episodic facilitation—instructional elements aligned with episodic memory (EM) processes—to affect learners’ memory of simulation training for an aviation procedure. Despite its assumed benefits in industry and theory, virtual reality (VR) has shown limited advantages over conventional media for training procedures, in part because prevailing frameworks emphasize semantic and procedural outcomes, leaving memory of training experiences as events underexamined. To address this gap, this work advances human factors research by examining EM as a design consideration, an outcome, and an explanatory mechanism for how simulation training experiences are remembered. Grounded in theories of EM and …

Sonic Costumes For Immersive Theme Park Storytelling: Developing Interactive Wearables To Enhance Performer, Audience, And Environment Interaction, Rachel Yee

Graduate Studies Theses and Dissertations 2026

Costumes enhance the themed experience through visual storytelling while also allowing performers to interact fluidly with a physical space. These garments are typically passive storytellers in theme parks, even if the performers interact directly with guests. Some garments coordinate with and react to elements of the themed environment, predominantly when worn by performers within live shows, parades, or streetmosphere settings. However, this interactivity is often available only at a distance from guests, causing a separation between audience and performer. For instance, lights on parade costumes, such as those throughout Disney’s Magic Kingdom Park, often synchronize only with parade floats and …

Infrared Systems And Their Application On Target Detection And Geolocation, Li Zhang

Graduate Studies Theses and Dissertations 2026

The infrared spectrum contains various sub-bands (from near infrared (NIR) to long-wave infrared (LWIR), which are specialized at different detection tasks. Objects that are well camouflaged to human vision can be highly noticeable in NIR imagery. For vision navigation, the varying illumination condition and the cluttered urban background poses challenges in the visible band but can easily be resolved by using a thermal imager operating in LWIR. Despite this potential, practical deployment remains limited by the lack of suitable platforms, task-specific datasets, and long-duration field validation. This dissertation addresses these gaps through the design and evaluation of two infrared sensing …

Ecological And Evolutionary Responses To Environmental Change In Two Large North American Mammals, George Zaragoza

Graduate Studies Theses and Dissertations 2026

Climate change and urbanization are resulting in rapid shifts in ecosystems. The effects of these changes are complex, and understanding how species respond is critical for predicting their impacts on genetic diversity and evolution, as well as changes in habitat suitability. Species can respond to these changes in two major ways: through behavioral or genetic adaptation, or by moving to more suitable habitat as conditions change. Adaptive genetic change, in particular, can support behavioral and physiological responses that enable species to persist in novel or changing environments, and understanding these changes can help predict how species will respond to anthropogenic …

Voltage Stability Enhancement Of Large Load Interconnections Using Syncronous Condensers, Muhammad Ibrahim Abbas

Graduate Studies Theses and Dissertations 2026

The rapid integration of hyperscale data centers as large, concentrated loads presents a growing voltage stability challenge in grids weakened by synchronous generator retirement and increasing inverter-based resource penetration. This work proposes a Jacobian-based sensitivity framework for systematically identifying voltage-critical buses and optimally siting synchronous condensers as voltage support resources. A voltage-weighted sensitivity index, extracted from the full Jacobian inverse, is introduced to combine network-wide reactive coupling strength with observed voltage drops into a single deployable placement criterion. Validation on IEEE 14-bus and 30-bus test systems under multiple loading scenarios demonstrates that the proposed criterion consistently identifies the correct placement …

Bowtie Antenna-Coupled Bi₂Te₃–Sb₂Te₃ Thermoelectric Detector For Millimeter-Wave Radiation, Rumana Zahir

Graduate Studies Theses and Dissertations 2026

We explore the development of antenna-coupled thermoelectric detectors for long-wavelength radiation using sputtered bismuth telluride (Bi₂Te₃) and antimony telluride (Sb₂Te₃) thin films. Detection in the infrared, millimeter-wave, and terahertz regimes is critical for sensing, imaging, and energy applications; however, many existing detectors rely on cryogenic operation, exhibit narrow spectral response, or require complex material systems. In this work, we investigate the feasibility of reliable, room-temperature long-wavelength detection using microfabricated thermoelectric thin films integrated with antenna structures. A systematic full-factorial experimental approach was employed to determine how sputtering parameters and post-deposition annealing influence …

Learning Weibull Loss Severity Models From Truncated And Censored Data, Majed Alkhasha

Graduate Studies Theses and Dissertations 2026

In modern actuarial science and risk management, due to various loss control mechanisms, observed severity losses are typically left-truncated at the deductible, right-censored at the policy limit, and scaled by a pre-specified co-insurance factor. This results in two types of actuarial payment random variables: payment-per-payment (PPP) and payment-per-loss (PPL). To learn ground-up Weibull loss severity models from PPP and PPL sample data, we implement two estimation techniques: Maximum Likelihood Estimation (MLE) and the dynamic Method of Trimmed Moments (MTM). MLE is employed to obtain efficient estimates of the Weibull shape and scale parameters. However, MLE may assign unnecessarily large point …

Effects Of Back-Pressure On Pseudo-Shock Systems, Emil C. Alunno

Graduate Studies Theses and Dissertations 2026

The isolator of a scramjet engine houses a pseudo-shock, a compressive flow structure that raises the static pressure and decelerates the incoming supersonic flow for efficient combustion while shielding the inlet from the elevated pressure downstream. Under sufficient back pressure the leading shock bifurcates and forms a shock train followed by a shockless mixing region, and the resulting system oscillates even under nominally steady conditions; this unsteadiness distorts the flow, can drive the pseudo-shock out of the isolator and unstart the inlet. This thesis experimentally examines how a pseudo-shock in a constant-area isolator at a measured entrance Mach number of …

Did They Think I Was Rude? The Emotional And Relational Consequences Of (In)Congruence Between Perpetrators’ Self- And Meta-Perceptions Of Workplace Rudeness, Nicholas C. Andriese

Graduate Studies Theses and Dissertations 2026

Workplace rudeness negatively impacts employees and costs organizations millions of dollars each year. Although much is known about the consequences of workplace rudeness, little is known about how perpetrators make sense of and respond to their (potentially) rude behavior. In this dissertation, I propose that perpetrators consider not only their self-perceptions of rudeness, or how rude they believe their actions were, but also their meta-perceptions of rudeness, or their beliefs about how rude another person perceived them to be. Because rudeness is subjective and people vary in their perceptual accuracy, self- and meta-perceptions of rudeness are unlikely to consistently …

Numerical Investigation Of Reacting Flow In Pmma-Fueled Solid Fuel Scramjet Combustors Under Experimental Test Conditions, Hunter Bassett

Graduate Studies Theses and Dissertations 2026

A simplified steady RANS-based numerical study of reacting flow in solid-fuel scramjet combustors is presented to evaluate the ability of commercial CFD frameworks to reproduce key features observed in experimental test sections. The work focuses on solid PMMA fuel in two supersonic combustor configurations: a cavity-assisted flameholding combustor and a variable-angle diverging combustor. The cavity combustor is analyzed as a baseline case and results are compared directly with experimental data. Three combustor geometry states corresponding to ignition, early-burning, and steady-burning conditions are investigated. Meshes are assessed through a systematic grid refinement method to establish grid independence. A novel variable-angle diverging …

Connecting The Existing Fiber Infrastructure To The Future With Antiresonant Hollow Core Fibers, Timothy Bate

Graduate Studies Theses and Dissertations 2026

Optical fiber systems based on solid-core silica waveguides underpin modern telecommunications, high-power laser delivery, precision sensing, and coherent optical systems. However, nonlinear effects, material absorption, and thermal limitations within silica increasingly constrain further scaling in both optical power and transmission performance. Antiresonant hollow-core fibers provide a promising alternative by guiding light predominantly in air, substantially reducing nonlinear interactions, latency, and optical damage while enabling transmission regimes inaccessible to conventional solid-core fibers. Despite rapid advances in antiresonant hollow-core fiber attenuation and power handling, one of the largest remaining barriers to widespread adoption is reliable integration with the existing solid-core fiber ecosystem. …

Sensory And Emotional Impacts On Modern Consumer Experiences, Winter E. Bland

Graduate Studies Theses and Dissertations 2026

This dissertation comprises two essays examining how environmental and psychological stimuli shape consumer experience, attitudes, and cognition. The first essay investigates the joint influence of scent temperature (warm versus cool) and scent arousal (stimulating versus relaxing) on experiential attitudes and cognitive performance in digitally mediated consumption environments. Across multiple lab experiments with biometric validation, findings reveal that these two scent dimensions interact to shape downstream outcomes. Warm, low-arousal scents (e.g., vanilla) enhance consumers' experiential evaluations of digital interactions but do not improve task performance, whereas cool, high-arousal scents (e.g., peppermint) boost cognitive efficiency and accuracy but do not elevate experiential …

Soil Texture And Organic Matter Influence Hydraulic Performance Of Stormwater Infiltration Systems Across Antecedent Moisture Conditions, Laura E. Andrade Barron

Graduate Studies Theses and Dissertations 2026

Stormwater infiltration systems are widely used to improve urban stormwater management by promoting drainage and groundwater recharge while treating nonpoint source pollution such as nutrients in surface runoff. Nutrient removal and hydrologic performance of these systems are closely coupled and both are dependent on characteristics of underlying soils. In this study, laboratory flow-through experiments were conducted using 30 intact cores taken from six soil types with different textures (0.99-16.63% clay content) and organic matter contents (OMC 0.44-93.3%). Measured cumulative fluxes from laboratory experiments were used to calibrate numerical models simulating flow through porous media (HYDRUS-1D). Calibrated models were used to …

A Systematic Review And Characterization Of Privacy Noncompliance In Real-World Applications, Alexander E. Charkiewicz

Graduate Studies Theses and Dissertations 2026

Software applications increasingly rely on user data to provide their functionality, but improper handling of such data can lead to serious privacy noncompliance with applicable regulations and policies. A prominent example is the Facebook–Cambridge Analytica scandal, in which a third-party application collected the personal data of approximately 87 million Facebook users without users' consent. Despite growing attention to privacy compliance, two key challenges hinder the systematic understanding and analysis of privacy noncompliance. First, unlike security vulnerabilities, which have been systematically categorized through taxonomies such as the Common Weakness Enumeration (CWE), privacy noncompliance lacks a technical taxonomy describing how it manifests …

Pioglitazone Uncouples Macrophage Inflammatory Signaling From Epithelial Oxidative Stress During Map Infection Mimicking Crohn’S Disease Treatment, Sabera Akter Bushra

Graduate Studies Theses and Dissertations 2026

Crohn’s disease (CD) is a chronic inflammatory bowel disease characterized by intestinal inflammation, epithelial barrier dysfunction, and abnormal immune signaling. CD pathophysiology is increasingly linked to Mycobacterium avium subspecies paratuberculosis (MAP) infection, which increases chronic macrophage activation and the production of inflammatory mediators that lead to epithelial damage. Among these mediators, CXCL10, TNF-α, and IL-6 contribute in inflammation, while NOX-1 and SERPINE-1 indicate epithelial oxidative stress and damage. Despite the role of macrophage-epithelial interaction in CD, selective pharmaceutical regulation of this axis remains unclear. Pioglitazone, an FDA-approved PPARγ agonist used for type 2 diabetes, is an appealing repurposing candidate, given …

Design, Fabrication Modeling, And Optical Metrology Of Mwir Silicon Metalenses, Weiyu Chen

Graduate Studies Theses and Dissertations 2026

Mid-wave infrared (MWIR) optical systems require compact, broadband, manufacturable components whose performance can be predicted and measured reliably. Silicon metalenses are attractive because silicon combines high refractive index, MWIR transparency, and semiconductor-compatible fabrication. This dissertation develops a scale-bridging design–fabrication-modeling–metrology framework for MWIR silicon metalenses.

A shared full-aperture framework connects meta-atom libraries, physical layout generation, angular-spectrum propagation, point-spread-function calculation, and focal-plane energy metrics. Building on this foundation, the Dispersive Sweatt Model (DSM) incorporates meta-atom dispersion into conventional ray-tracing software, enabling broadband co-optimization of metasurfaces and refractive elements. A process-aware design framework then incorporates scanning electron microscopy (SEM)-measured height–radius relationships produced by …

An Empirical Comparison Of K-Nearest-Neighbors And Logistic Regression Classification Models, Jackson Cushing

Graduate Studies Theses and Dissertations 2026

This thesis presents an empirical comparison of two classification methods: Logistic Regression and K Nearest Neighbors (KNN). The primary objective of this research is to evaluate the strengths and limitations of each method when applied to real-world datasets. Several publicly available datasets on diabetes, breast cancer, heart attack risk, and cardiovascular disease, were analyzed. For each dataset, K Nearest Neighbors models were implemented in the same way logistic regression had already been applied. The results demonstrate that while logistic regression offers interpretable parameter estimates and performs well when the underlying predictor and outcome relationship is approximately linear, however KNN can …

Vaccine Hesitancy In Arabic Discourse: A Multi-Method Social Media Study, Nada Dimashkieh Chehab

Graduate Studies Theses and Dissertations 2026

Vaccine hesitancy — the state of uncertainty about vaccination — poses global public health challenges, undermining efforts to prevent infectious diseases. It is also a contextual phenomenon, shaped by social and political forces. While survey-based research on vaccine hesitancy is abundant both globally and in the Arab world, humanities-oriented approaches using discourse analysis remain limited especially in Arabic on social media: some have tracked trends on Twitter, but virtually none have done so on Facebook. This dissertation addresses these gaps through a multimethod design combining Textual and Trend Analyses and Critical Discourse Study. It examines vaccine-related trends and discourses among …

Machine Learning Modeling Of In-Situ Effective Thermal Conductivities And Ablation Behaviors Of Ceramic Matrix Composites Under Hydrogen Combustion Environments For Gas Turbine Engines, Jayanta Bhusan Deb

Graduate Studies Theses and Dissertations 2026

Through the integration of experimental characterization, machine learning, deep learning, numerical modeling, and physics-informed artificial intelligence, this dissertation explores the thermal performance of polymer-derived ceramic matrix composites (CMCs) for hydrogen combustion environments. The polymer infiltration and pyrolysis (PIP) process was used to create Yttria-stabilized zirconia (YSZ)-fiber-reinforced ceramic matrix composites, which were then experimentally assessed under hydrogen torch and hydrogen combustion conditions typical of next-generation gas turbine and aerospace propulsion systems. Front- and back-surface temperature measurements were used to continually monitor thermal reactions, and post-test microstructural characterization and numerical simulations were carried out to evaluate material integrity and heat-transfer behavior. To …

Independent And Interacting Effects Of Co-Presence And Social Media 'Likes' On Online Disinhibition, Margaret M. Doheny

Graduate Studies Theses and Dissertations 2026

Social media platforms have fundamentally transformed interpersonal communication by creating environments in which behaviors are publicly reinforced through visible social feedback systems such as “likes.” Although prior research has linked online environments with increased disinhibition and negative behavior, existing literature has primarily focused on anonymity and invisibility as the primary mechanisms underlying these effects. However, the mechanistic role of physical and psychological co-presence in driving online disinhibition has received little empirical investigation. The central aim of the present study was to determine whether reduced social presence and the selective reinforcement of negative content contribute to online disinhibition and anticipatory reward-seeking …

Flow Field Characterization Of The Hyperreact Vitiated Hypersonic Wind Tunnel, Erik R. Fernandez

Graduate Studies Theses and Dissertations 2026

Reliable interpretation of hypersonic ground-test data requires knowledge of the thermochemical state delivered to the test section, especially in combustion-heated facilities where the gas is chemically altered before nozzle expansion. This thesis investigates the HyperReact vitiated hypersonic wind tunnel using the effective specific-heat ratio, γeff, as an experimentally inferred indicator of the coupled chemical and gas-dynamic behavior of hydrogen-air vitiated flow. HyperReact produces high stagnation temperatures through hydrogen-air combustion before expanding the mixture through interchangeable converging-diverging nozzles. During this expansion, temperature-dependent specific heats, molecular-weight changes, finite-rate chemistry, and internal energy relaxation can modify the relationship between Mach number, pressure ratio, …

Investigating The Impact Of School Leaders’ Leadership Style And Teachers’ Intrinsic Motivation For Improved Science Instruction In Elementary Schools, Leila M. Greene

Graduate Studies Theses and Dissertations 2026

A report by the National Academies of Sciences, Engineering, and Medicine, determined that 69% of U.S. elementary teachers are not prepared to teach science, especially in the areas of earth/space and physical sciences. As a result, some elementary teachers avoid teaching science. School administrators play a key role in providing a supportive environment to inspire and motivate elementary science teachers. For this reason, the study utilized the Self-Determination Theory (SDT), to examine three types of school leadership styles (Transformational, Transactional, and Laissez-Faire) and how they impact the intrinsic motivation for elementary science teachers in three areas including autonomy, competency, and …

Deciphering Ultrafast Photoinduced And Photocatalytic Reaction Dynamics On Oxide Surfaces: Direct Detection Of Radical Intermediates, Fragment Trapping, And Carbon–Carbon, Carbon–Oxygen, And Carbon–Hydrogen Bond Formation Pathways, Aakash Gupta

Graduate Studies Theses and Dissertations 2026

Understanding photoinduced reactions at solid interfaces is essential for advancing heterogeneous photocatalysis, surface photochemistry, and energy conversion technologies. This dissertation investigates the ultrafast dynamics of reactive intermediates, fragment trapping, and radical-mediated bond formation on oxide surfaces using time-of-flight mass spectrometry in conjunction with femtosecond pump-probe spectroscopy. Various experimental findings are validated through collaborations via density functional theory (DFT). By combining temporal, mass, and energy-resolved measurements, this work provides molecular-level insight into the elementary processes governing light-driven surface reactions. The photodissociation dynamics of CH₃I adsorbed on TiO₂(110), TiO₂(100), and amorphous silicon oxide surfaces are examined …

Strategic Signaling Or Structural Friction?: How Ai Disclosure Moderates Resource-Performance Dynamics In Hotels And Restaurants, Jaewan Heo

Graduate Studies Theses and Dissertations 2026

Artificial intelligence (AI) has become an increasingly important strategic issue in the hospitality industry. While prior research has primarily examined AI as an operational technology that improves efficiency and service delivery, less attention has been paid to how AI-related disclosures influence investor evaluations of firm resources. This dissertation investigates whether AI-related disclosures moderate the relationship between organizational resources and financial performance in publicly traded hospitality firms.

Drawing on signaling theory and the resource-based view, this study conceptualizes AI disclosures as strategic signals that shape investor perceptions of firm capabilities and future value creation. Firm-level financial data were obtained from Compustat …

A Case Study Examining Organizational Influences On Student Teacher Placement In K-12 Classrooms, Rachel L. Ickes

Graduate Studies Theses and Dissertations 2026

Student teaching is a prominent and required learning experience in most teacher education programs. The learning that takes place in student teaching blends pedagogy with practice. However, not all student teaching placements provide positive learning experiences for student teachers. This descriptive case study examines the organizational factors that affect the process of student teacher placement at K-12 classroom sites by one teacher education program. For this case study, one teacher education program in the southeastern United States was selected as the case site, and the case for this study is the process of student teacher placement. Semi-structured interviews, observation, and …

Integrated Optical Probes For Confocal Scanning Imaging And Adjustable Coherent-Gated Dynamic Sensing, Yonglin Huang

Graduate Studies Theses and Dissertations 2026

Optics and photonics have been one of the most important sciences and technologies that impact modern human life in a big way. For example, fiber-optics for communications and artificial intelligence. Optical probes are critical components for optical imaging and optical sensing technologies that have been actively researched and developed in the past decades. Advanced fiber-optic sensor probes with smaller size, better performance, lower noise, higher photon efficiency, rapid sensing time, and lower cost are needed in many applications, such as nanoscale material science, chemistry, and biomedical fields, etc.  In this project, new fiber-optic sensor probe technologies and integrated micro-optic devices …

Integrated Corridor Management Framework For Severe Freeway Incidents, Sanjida Afroz Iqra

Graduate Studies Theses and Dissertations 2026

Traffic incidents are a major source of non-recurrent congestion on urban freeways, generating substantial mobility, safety, and economic impacts. Severe incidents that block multiple or all travel lanes are particularly disruptive because they degrade freeway operations and propagate congestion onto surrounding arterials. Effective Integrated Corridor Management (ICM) requires the ability to identify severe incidents, estimate their network-wide impacts, and anticipate the traffic conditions and driver behaviors that contribute to instability. This dissertation develops a data-driven ICM framework to address these challenges using real-world incident, crash, detector, and connected vehicle data from major Central Florida corridors, including I-4 and SR-417. The …

The Odyssey Of Emotion Regulation In Extremis: How Challenges Lead To Team States Through Regulation And Psychological Safety In Ice, Andres Kaosaar

Graduate Studies Theses and Dissertations 2026

Isolated, confined, and extreme (ICE) teams experience challenges that require continuous emotional adaptation. Although emotion regulation (ER) has been recognized as critical for functioning in these contexts, little is known about how specific challenges shape regulatory responses, how team climate influences those responses, and how individual regulation accumulates into team-level outcomes. This dissertation develops and tests a multilevel framework linking challenge exposure, perceived psychological safety, individual ER, team emotions, and team viability in space analog environments. Data were collected from 36 crews (N = 184) participating in two-week missions at two space analog stations, yielding 2,577 daily observations and …

The Impact Of Criminal Justice System Contact On Adolescents In The U.S.: Prescription Drug Misuse, Marijuana Use, Health Outcomes, And Demographic Characteristics, Fadime Gokce Karaaslan

Graduate Studies Theses and Dissertations 2026

Criminal justice system (CJS) contact remains a pervasive feature of social life in the United States, with both direct and indirect consequences for adolescents and their families. Although previous research has explored the consequences of direct CJS contact, less is known about how indirect or vicarious contact affects adolescents’ well-being and substance use. Drawing on data from the Future of Families and Child Wellbeing Study (FFCWS), this study investigates the association between parental incarceration and vicarious police stops, defined as police stops involving parents, siblings, friends, neighbors, or other social ties, and adolescent well-being. Findings indicate that CJS contact is …