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On Performance And Applications Of A Liquid Fueled Pulsed Flame Jet Igniter, Gerardo A. Rodriguez

Graduate Studies Theses and Dissertations 2026

As global demands for supersonic and hypersonic flight heighten, high-speed air breathing propulsion technologies stand out as a worthwhile direction to overcome many of the limitations that turbomachinery-based engines face at supersonic speeds. Air breathing propulsion concepts are attractive for their geometrical simplicity, using supersonic incoming air to provide compression. Scramjet flight vehicles operate within the hypersonic flight regime and have been a global research topic, especially in the 21st century, for defense and combined cycle engine architectures. As scramjet technology continues maturing towards widespread use, efforts have converged on liquid hydrocarbon fuels for storage, range, and operational benefits. Flight …

Examining Principals' Perceptions Of Their Preparedness To Lead In Title I Schools, Tiffany Roebuck

Graduate Studies Theses and Dissertations 2026

Principals serving in Title I schools face complex instructional, organizational, cultural, and community related demands that require specialized leadership preparation and support.  The purpose of this qualitative phenomenological study was to explore the lived experience of principals serving in urban Title I schools regarding their preparedness, supports, challenges, and successes as instructional leaders. The study also examined principals' perceptions of culturally proficient leadership and principal preparation program attributes considered essential for leadership readiness in high-needs school settings. Guided by the Culturally Responsive School Leadership (CRSL) framework, data were collected through semi-structured interviews with 10 principals serving in urban Title I …

A Modular Virtual Reality Training Framework For Multi-Target Drone Defense, Susann Schleupner

Graduate Studies Theses and Dissertations 2026

Unmanned aerial systems (UAS), commonly referred to as drones, have become a rapidly growing challenge in modern military operations. In particular, the increasing use of small, agile, and low-cost systems—such as first-person-view (FPV) drones and coordinated multi-drone deployments—places high cognitive demands on operators, requiring rapid target detection, prioritization, and decision-making under time pressure.

Existing training approaches either rely on costly and logistically constrained live exercises or focus primarily on isolated piloting and shooting tasks, without sufficiently addressing these cognitive demands. At the same time, advances in commercial off-the-shelf (COTS) virtual reality (VR) hardware enable scalable, flexible, and repeatable training environments. …

Visual Cues Of Human-Likeness, Not Salience, Impact Trust-Related Human-Computer Interaction, Jordan Schotz

Graduate Studies Theses and Dissertations 2026

As interactions with digital agents become increasingly integrated into daily life, understanding how visual representations influence social decision-making is critical. Previous research in human-computer interaction has frequently confounded the psychological effects of an agent's perceived human-likeness with the underlying visual salience of the stimuli. To address these persistent gaps, the present study systematically isolated the effects of human-likeness and visual cue trustworthiness on trust behavior while controlling for objective image properties. The present study expanded on and normed the Virtual Avatar Facial Stimuli Set (VAFSS), a comprehensive database comprising hundreds of identity-matched photographs and computer-generated avatars varying across a spectrum …

Evaluating The Brain-Muscle Connectivity Of Cyclic Ankle Pedaling Movement In A Clinical Setting, Matthew K. Shanosky

Graduate Studies Theses and Dissertations 2026

Clinical neurorehabilitation requires objective biomarkers to accurately detect and monitor neuromotor impairments. While traditional metrics are favored for their efficiency and minimal equipment demands, they typically rely on subjective observation and lack physiological resolution. High-resolution electrophysiological technologies, such as electroencephalography (EEG) and electromyography (EMG), offer objective insights into nervous system dynamics; however, prolonged data acquisition times have hindered their translation into frontline clinics. To bridge this translational gap, this study developed a time-efficient experimental paradigm designed for rapid clinical deployment. Healthy participants completed two initial resting baseline trials before performing an externally paced, dynamic, cyclic ankle movement task utilizing simulation …

Concept Drift Detection For Streaming Data Using One-Class Classification, Poorna Sandamini Senaratne

Graduate Studies Theses and Dissertations 2026

Modern machine learning systems are increasingly deployed in streaming environments where data arrive sequentially and the underlying data-generating process may evolve over time. This phenomenon, known as concept drift, can significantly degrade model performance if not detected and addressed in a timely manner. This dissertation proposes a principled framework for concept drift detection based on one-class classification, integrating neural network embeddings with Support Vector methodologies.

The proposed approach leverages neural networks to learn compact and informative embeddings of input data, capturing complex nonlinear structures in a lower-dimensional latent space. These embeddings are then used to construct a statistical description of …

Revisiting The Foundation Of Strategic Core Theory: Informal Roles And Teamwork Roles In Work Team Centrality, Allen Thomas Shorey

Graduate Studies Theses and Dissertations 2026

Strategic core theory makes a distinction between roles within a team that are central to the team’s workflow (i.e., core roles) and those that are not central (i.e., non-core roles) (Humphrey et al., 2009). This line of work has shown that attributes, such as job-related skill of core team members, were more predictive of team performance than those of non-core members. However, this line of work has primarily examined core and non-core roles as defined by formal taskwork roles. In this thesis, I examine patient care teams and management simulation teams with the principal conviction that (a) informal roles and …

Overcoming The Glass Wall: Self-Employment As A Career Strategy For Immigrant Professionals, Barbara Silva

Graduate Studies Theses and Dissertations 2026

Skilled immigrant professionals frequently experience barriers that limit their ability to secure employment opportunities aligned with their qualifications in host-country labor markets. Although prior research has documented some of the challenges these professionals face, such as credential devaluation and discrimination, less is known about why recruiters perceive immigrant candidates with similar qualifications differently and why some immigrants navigate the labor market more successfully than others. Drawing on Status Characteristics Theory, this dissertation examines how the location and type of immigrant professionals’ prior work experience shape hiring-related outcomes by influencing recruiters’ perceptions of competence and acculturation. First, I review the literature …

Study On Fracture Toughness Under Different Modes Through Continuum Damage Mechanics Based Fracture Locus, Yeting Sun

Graduate Studies Theses and Dissertations 2026

Traditional elastic-plastic fracture mechanics (EPFM) relies on crack-tip analysis, whereas continuum damage mechanics (CDM) is typically calibrated from uncracked bodies. This dissertation aims to bridge the gap between these two fundamental branches by explicitly linking fracture toughness with ductile damage models. Based on the assumptions regarding Mode I crack deformation, analytical solutions are derived to establish a novel relationship among Mode I fracture toughness, CDM-based ductile fracture strain, and material strain hardening capability. This theoretical framework is subsequently extended to encompass Mode II and Mode III loading conditions. To validate the proposed relationships, finite element (FE) models are developed in …

Exploring Barriers And Facilitators Of Mental Health Treatment For Law Enforcement Officers: The Impact Of Police Occupational Culture, April Reed

Graduate Studies Theses and Dissertations 2026

Prior research has explored the impact of police culture on mental health stigma among law enforcement, however, a deeper understanding about how different aspects of police culture may inhibit or facilitate mental health treatment utilization is needed to inform policy and practice. This dissertation explores the relationship between police culture and mental health using a qualitative research design. Twenty-five (n=25) law enforcement officers from a county sheriff’s office in Central Florida were interviewed and participant observations were conducted during a three-month period. The present study sought to address the following research questions: What are the experiences of the job and …

Two Essays On Out-Of-Town Home Buyers, Kamrul H. Talukdar

Graduate Studies Theses and Dissertations 2026

This dissertation analyzes the price premia paid by Out-of-Town (or non-local) home buyers. The first essay investigates the role of social connectedness in the price premia paid by non-local buyers in the residential housing market. Using over 74,000 residential transactions from Orange and Seminole counties, Florida between 2016 and 2019 and exploiting the Social Connectedness Index (SCI) constructed based on Facebook friendship links, I show that non-local buyers who come from regions which are more socially connected to the purchase location pay about 1.8% to 2.1% lower premia compared to those coming from less connected regions. This effect is attributed …

Online Risk And Harm For Marginalized Users: How Social Influence Amplifies Or Mitigates Vulnerability, Tangila Islam Tanni

Graduate Studies Theses and Dissertations 2026

Social media has reshaped how people connect, communicate, and influence one another, yet these environments also create harms that disproportionately affect marginalized users. Participation in online communities can expose users to identity-based harassment, emotional distress, and the normalization of harmful attitudes, shaping identity, well-being, and participation online and offline. Prior work has documented many forms of online harm, yet less is understood about how harmful norms and behaviors are reinforced across different forms of social media interaction, from private direct messages to online communities. Guided by the Social Ecological Model, this dissertation investigates how online harms toward marginalized users emerge …

Integrated Design And Trade Study Of A Sub-Ambient Ammonia Fuel Storage And Delivery System For Narrow-Body Commercial Aircraft, Ethan Taylor

Graduate Studies Theses and Dissertations 2026

This study develops an integrated design framework for a sub-ambient anhydrous-ammonia fuel storage and delivery system for narrow-body commercial aircraft, using the Boeing 737 MAX 8 as the baseline platform. Ammonia was selected because it contains no carbon in its molecular structure, benefits from an established global production and distribution infrastructure, and offers more practical storage conditions than several alternative carbon-free energy carriers. However, its relatively low energy density, toxicity, material-compatibility requirements, and combustion hazards require substantial modifications to power conventional commercial aircraft fuel storage and delivery systems.

The study proposes an integrated design and initial analysis of a sub-ambient …

Memory-Efficient Acceleration For Emerging Applications Via Hardware/Software Co-Design, Shilin Tian

Graduate Studies Theses and Dissertations 2026

Emerging artificial-intelligence and data-intensive scientific workloads increasingly face a memory wall: irregular access patterns and large intermediate data volumes make data movement, rather than arithmetic, the primary constraint on performance and energy efficiency. This dissertation develops a memory-centric hardware/software co-design methodology that jointly reshapes algorithms, architectures, and dataflows to retain frequently reused data on chip. The methodology is demonstrated through three accelerators and an RTL design tool. VITA replaces multi-head attention in vision-transformer-based 3D human mesh recovery with hardware-friendly average pooling and maps the resulting operators to a reconfigurable datapath, achieving 5.05-fold and 69.12-fold speedups over a state-of-the-art GPU and …

Unmasking Impression Management: Large Language Models For Detecting Socially Desirable Responding In Open-Ended Situational Judgment Tests, Barret Vermilion

Graduate Studies Theses and Dissertations 2026

Socially desirable responding (SDR) — the tendency to present oneself in an overly favorable light — remains a persistent validity concern in industrial-organizational psychology. Contemporary theory frames SDR as multidimensional, distinguishing agentic impression management (AM; inflating competence, dominance, and achievement) from communal impression management (CM; inflating warmth, cooperation, and prosocial qualities). Existing measures of AM and CM rely on self-report, which captures these constructs only at the level of generalized trait-like tendencies rather than as they naturally unfold in applicants' own language. This dissertation proposes a text-based alternative: detecting AM and CM in open-ended situational judgment tests (SJTs) of Big …

Two Papers Exploring Cognitive Fit Theory And Data Visualization In Accounting, Kelly Wellman

Graduate Studies Theses and Dissertations 2026

This dissertation examines how data visualization design influences judgment and decision making in accounting using cognitive fit theory as a unifying framework. As visualization tools such as dashboards, Excel, Tableau, and Power BI become increasingly prevalent, understanding which design choices improve performance has become critical. The first paper provides a structured literature review of cognitive fit theory from 1991 through 2025, synthesizing research across accounting and related disciplines and tracing its evolution from early graph vs tables comparisons to mor recent work incorporating task complexity, individual differences, and design-specific features. The review identifies key gaps, including limited attention to difference …

Advanced Ysz/Si(B)Cn And Bnnt/Si(B)Cn Ceramics Matrix Composites For Extreme Environments In Hydrogen Combustion, Yiting Wang

Graduate Studies Theses and Dissertations 2026

The growing demand for carbon-neutral energy conversion has accelerated the development of hydrogen-fueled gas turbine systems, which operate at significantly higher temperatures and more chemically aggressive environments than conventional natural gas turbines. To meet these stringent requirements, ceramic matrix composite (CMC) materials consisting of yttria-stabilized zirconia (YSZ) fiber reinforced Si(B)CN ceramic matrix were developed. To further enhance in-plane heat dissipation, thermal stability, thermal shock resistance, and thermal cycling performance, a Si(B)CN/Boron Nitride Nanotubes (BNNT) nanocomposite coating was incorporated onto the YSZ/Si(B)CN composites. Microstructural characterization confirmed the formation of a continuous Si(B)CN ceramic matrix reinforced with uniformly distributed BNNTs. The resulting …

Switching Things Up: Investigating The Costs Of Switching Between Tasks Of Varying Interdependence And Factors That Influence These Transitions, Taylor A. Wilhelmy

Graduate Studies Theses and Dissertations 2026

Though researchers have indicated that there is a high probability teams will transition between tasks of varying interdependence (Benishek & Lazzara, 2019; Mesmer-Magnus et al., 2016), there is a need to further examine this idea (Smith-Jentsch, 2015; Mesmer-Magnus et al., 2016) as few have actually studied it. Expanding upon Moon et al. (2004), this study examines the costs associated with transitioning between two tasks of varying levels of interdependence (i.e., pooled and team interdependence; Saavedra et al., 1993), how these costs vary depending on the order the tasks are engaged while examining how team cognition (i.e., transactive memory systems) and/or …

Human And Ai Support In Business Simulations: A Quasi-Experimental Mixed Methods Study Of Performance At Scale, Sara Willox

Graduate Studies Theses and Dissertations 2026

Large classes change what instruction looks like. In hybrid business courses with high enrollment, it becomes harder to respond to individual students, and performance can suffer as a result. This study looked at what happens when that gap is addressed in different ways during an eight-week business simulation at the University of Central Florida. Six course sections were divided into three study groups. One group worked without support, one received instructor guidance, and one used AI tools that included a course search system and generative responses. Student outcomes were based on weekly profit and loss recorded in Sim Companies. The …

Careless Responding: Testing The Theory Of Vigilance, Rusty Wilson

Graduate Studies Theses and Dissertations 2026

Careless responding (CR) has been identified as a threat to the psychometric integrity of cognitive and non-cognitive tests, with much of the current research focusing on the identification and removal of carelessness from dataset. While this research has proved fruitful in improving data quality, there has been a recent push to move towards preventing carelessness as opposed to post-hoc removal, which harms statistical power. However, the most common prevention strategy to prevent carelessness (pre-survey warnings) has shown equivocal effects. Additionally, the literature lacks an agreed upon theory to explain why carelessness occurs. To address these gaps I introduce theory from …

How Did Covid-19 Affect Volunteer And Donor Management For Human Services Agencies? What Are The Lessons For Future Response?, Nina Yon

Graduate Studies Theses and Dissertations 2026

The COVID-19 pandemic created unprecedented challenges for human services agencies, disrupting the interdependent systems of volunteer engagement and donor support essential to nonprofit sustainability. This study integrates insights from literature, theory, and empirical analysis to examine how nonprofit organizations adapted their volunteer and donor management strategies during this prolonged crisis. Drawing on Contingency Theory and Resource Dependence Theory (RDT), the research explores how organizational structures and strategies evolved in response to shifting environmental conditions, health mandates, and resource constraints. Using a multiple-case qualitative design, data was collected from semi-structured interviews with 20 leaders representing five Central Florida human services agencies, …

Designing Narrative-Based Ai Assistance For Sensemaking In Collaborative Environments: Case Studies In Education And Dementia Care, Dylan Edward Moore

Dartmouth College Ph.D Dissertations

This thesis addresses a gap in the human-computer interaction literature regarding the design, development, and evaluation of narrative-based AI assistance for collaborative, complex problem solving. I explore this design space through three case studies across the domains of education and dementia care. This work encompasses multi-year industry partnerships and longitudinal fieldwork, user-centered design, dataset curation, model training, and system evaluation.

Specifically, the first case study considers a story-based web platform for teaching AI literacy through peer-generated, personalized narrative scaffolding. Learners on the platform showed significant knowledge gains and other learning-related outcomes. To describe the novel design of this system, I …

Knowing The User: Representation, Contextualization, And Predictive Internalization In Personalized Models, Zhongyu Ouyang

Dartmouth College Ph.D Dissertations

Intelligent systems increasingly anticipate which items a person will prefer, adapt generated text to a familiar style, and carry relevant information across interactions. These capabilities invite the impression that a model knows its user. In the technical sense studied here, a model knows a user when it carries information specific to that user, uses that information in the relevant context, and generalizes beyond the observations used to build the user state. Knowing is thus a measurable relation among user evidence, model state, context, and held-out user-specific behavior. The research community generally studies this family of systems under the term personalization, …

Investigating The Association Between Polycystic Ovary Syndrome (Pcos) And Idiopathic Intracranial Hypertension (Iih): A Cross-Sectional Analysis, Savannah L. Adams

Graduate Studies Theses and Dissertations 2026

Polycystic ovary syndrome (PCOS) and idiopathic intracranial hypertension (IIH) are chronic conditions that disproportionately affect women of reproductive age and share several metabolic risk factors, including obesity, insulin resistance, and hormonal dysregulation. Despite growing clinical interest in a potential relationship between these conditions, limited research has examined awareness, knowledge, symptom presentation, and barriers to healthcare among young adult populations. The purpose of this study was to investigate awareness, knowledge, perceived healthcare barriers, and potential associations between PCOS and IIH among college-aged individuals. A cross-sectional survey was administered to students aged 18-25 at the University of Central Florida through classroom recruitment …

Lucha Libre: Legends Of The Mask, Anthony J. Aguilar

Graduate Studies Theses and Dissertations 2026

Lucha libre, also known as Mexican wrestling, is a cultural phenomenon whose history dates to 1933. Every wrestling match pits flamboyantly costumed and masked wrestlers (luchadores), classified as either the good guys (técnicos) or the bad guys (rudos), against each other in choreographed and dramatized battles. Although lucha libre is often seen as campy or “low brow” due to its exaggerated, theatrical style, this perception overlooks the deeper cultural significance and narrative potential inherent in the form. This thesis will explore the cultural evolution of lucha libre as a highly interactive themed ride attraction. By integrating guest participation through custom …

Critical Analysis Of Legal Education: Faculty Perspectives Of Law School's Role In Producing Practice-Ready Graduates, Sophia M. Akel

Graduate Studies Theses and Dissertations 2026

Legal education has long been the subject of harsh, widespread criticism due to concerns about its ability to adequately prepare students for legal practice. Newer attorneys have reported feeling incapable of performing even the most basic functions of their job after graduation from law school (Merritt & Cornett, 2020). Despite this troubling reality, law schools largely continue to function as they always have (Cramton, 1981). To gain insight directly from important figures in legal academia, this study examined law faculty perceptions on legal education’s role in producing practice-ready graduates. A mixed-methods survey design incorporating both quantitative descriptive and qualitative elements …

The Role Of Personality Traits In The Relationship Between Executive Functioning And Identity Dimensions, Faith Alexander

Graduate Studies Theses and Dissertations 2026

This study examined the mediating role of personality traits on the relationship between executive functioning (EF) domains and dimensions of identity development. A cross-sectional, correlational design was utilized. 364 participants (MAge = 20.03, SD = 4.11) completed self-report measures of EF, personality, and identity. It was hypothesized that the Big 5 personality traits would mediate associations between EF components (working memory, inhibitory control, and cognitive flexibility) and adaptive or maladaptive identity dimensions. Results indicated that conscientiousness partially mediated the relationship between working memory and identification with commitment, while fully mediating the relationship between working memory and commitment making, suggesting …

Passenger Pigeons, Dodos, Neanderthals, Jordan Alexander

Graduate Studies Theses and Dissertations 2026

Passenger Pigeons, Dodos, Neanderthals is a short story collection rooted in Afrofuturism and Southern literature. Passenger Pigeons centers the experiences of queer Black American women in various settings, from Mars to rural Florida. The title story of the collection follows Teri, a human on Mars, attempting to integrate into a society of Martians who exoticize and tokenize her. In this story, I use science fiction as a vehicle to confront the microaggressions and overt racism people of color often experience in professional environments. “Rather Be the Devil,” is a fabulist story detailing the character Man’s journey to find his missing …

Robust Linking Estimation In Item Response Theory Using Quantile Regression: Applications To The Graded Response And Generalized Partial Credit Models, Ibrahim Almansour

Graduate Studies Theses and Dissertations 2026

This dissertation investigates robust estimation of linking coefficients in Item Response Theory (IRT) using quantile regression and its extensions. Linking procedures are essential for placing item and ability parameters from different test forms onto a common scale, thereby ensuring comparability of examinee scores across administrations. Traditional approaches such as moment methods, characteristic curve methods, and mean-based regression procedures like Ordinary Least Squares (OLS) and Generalized Least Squares (GLS) perform adequately under ideal conditions but tend to lose accuracy when ability distributions deviate from normality or include outliers.

To address these limitations, this research proposes a quantile-based regression framework that estimates …

Un Lugar A Donde No Puedo Volver: Perteneciendo En La Distancia, Alberto J. Alonso

Graduate Studies Theses and Dissertations 2026

“A Place I Cannot Return To: Distance and Belonging” investigates how home is not limited to a fixed place, but instead a reconstruction sustained through memory and longing, which focuses on personal experiences of being away from Puerto Rico. I contribute to this broader dialogue by offering a deeply personal perspective shaped by the complexities of cultural belonging. Through photography, collage, and painting, my art practice reconstructs fragmented visual narratives of lived experience to explore homesickness, nostalgia, and displacement, examining how personal and shared histories become anchors to what continually slips away. Although I can physically return to Puerto Rico, …