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Examining Relationships Between Pre-Arrival Information, Perceived Preparedness, And Distressing Call Outcomes Among Firefighters, Victoria L. Steigerwald Jan 2026

Examining Relationships Between Pre-Arrival Information, Perceived Preparedness, And Distressing Call Outcomes Among Firefighters, Victoria L. Steigerwald

Graduate Studies Theses and Dissertations 2026

Responding to distressing emergency calls increases firefighters’ risk for negative mental health outcomes, including posttraumatic stress disorder, warranting investigation into factors that can be targeted to reduce their risk for call-related distress. The present study examined whether the completeness of pre-arrival information about a distressing call reduced firefighters’ peri- and post-call distress via their perceived preparedness for the call and whether general self-efficacy moderated the relationship between pre-arrival information completeness and perceived preparedness. Data were analyzed from 173 active firefighters in the United States (89.0% male, mean age=37.98 years) who completed an online survey asking them to report on levels …


For Whom The Tale’S Told: Multilevel Perspective On Narrative And Identity In Information Ecosystems, Jihye Song Jan 2026

For Whom The Tale’S Told: Multilevel Perspective On Narrative And Identity In Information Ecosystems, Jihye Song

Graduate Studies Theses and Dissertations 2026

In contemporary online information environments, narratives do not merely convey facts. They organize meaning, signal identity, and guide collective sensemaking. During periods of crisis and uncertainty, these processes become especially salient, as individuals and communities turn to social media to interpret unfolding events. At the same time, these environments are shaped by complex sociotechnical dynamics, including platform affordances, algorithmic amplification, elite influence, and grassroots participation. These dynamics form ecosystems in which narratives and identities are constructed, contested, and stabilized. Drawing on theory and empirical analyses of COVID-19 discourse on Twitter, this work develops and applies a multilevel framework to explain …


The Reliability, Validity, And Sensitivity Of Physical Working Capacity At The Pain Intensity Threshold, Danielle A. Sterner Jan 2026

The Reliability, Validity, And Sensitivity Of Physical Working Capacity At The Pain Intensity Threshold, Danielle A. Sterner

Graduate Studies Theses and Dissertations 2026

The purpose of this dissertation was to evaluate the reliability, validity, and responsiveness to training intervention of a pain-anchored capacity threshold, the Physical Working Capacity at the Pain Intensity Threshold (PWCPIT), as a practical submaximal marker of endurance-related exercise tolerance. Study one examined the test-retest reliability of pain-based, perceptual, and physiological physical working capacity measures in recreationally active men using a standardized multi-bout cycling protocol, with pain intensity responses demonstrating strong reproducibility and low measurement error, supporting the stability of pain-anchored thresholds when standardized procedures are applied. Study two evaluated the validity of PWCPIT by examining pain …


Experimental Characterization Of Obstacle-Driven Ddt And The Performance Of Relief Dump Tanks In Detonation Systems, Bryan Suarez Jan 2026

Experimental Characterization Of Obstacle-Driven Ddt And The Performance Of Relief Dump Tanks In Detonation Systems, Bryan Suarez

Graduate Studies Theses and Dissertations 2026

This study investigates the lifecycle of a detonation event in a modular detonation
tube facility. It focuses on the mechanisms of deflagration-to-detonation transition
(DDT) and the effectiveness of a pressure relief system. With a stoichiometric
hydrogen-oxygen mixture, the research aims to characterize the effect of
interchangeable turbulator obstacles on the DDT process. By varying blockage
ratios and obstacle geometries in the pre-detonation section. This study identifies
how physical characteristics influence transition efficiency. The experimental data
collected includes pressure spikes and wave speed which were then used to
validate against the Chapman-Jouguet (CJ) theory at initial pressures of 350 Torr
and …


Federated Learning In The Era Of Foundation Models, Guangyu Sun Jan 2026

Federated Learning In The Era Of Foundation Models, Guangyu Sun

Graduate Studies Theses and Dissertations 2026

The emergence of large-scale foundation models has reshaped computer vision and multi-modal learning, but their substantial computational and communication demands pose significant challenges for deployment in federated learning (FL) systems. Federated learning enables collaborative model training across decentralized clients without sharing raw data, offering strong privacy guarantees. However, adapting foundation models in FL remains difficult due to communication bottlenecks, heterogeneous data distributions, limited device resources, and scarce labeled data. This dissertation presents a unified line of research that addresses these challenges through four complementary frameworks, progressively advancing the efficiency, personalization, and practicality of foundation model adaptation in federated settings.

First, …


Building Eden Where We Can, Ireland Thomas Jan 2026

Building Eden Where We Can, Ireland Thomas

Graduate Studies Theses and Dissertations 2026

Building Eden Where We Can is a nonfiction memoir told in vignettes that come together to build a wider story. Through these vignettes, we are shown a narrator who is simultaneously surviving an abusive family, navigating a rare diagnosis, and coming to terms with their queerness. By braiding narratives and maintaining these various threads, this collection examines the intersections of sickness and religion, tradition and freedom, as well as fear and love. The lattermost dichotomy is represented in the narrator’s ultimate choice to leave behind a life of fear in the mother figure’s safe cage. In exchange, they receive a …


Abig4l: A Semantic Reasoning Engine For Verilog Via Abstract Interpretation, Alicia Thoney Jan 2026

Abig4l: A Semantic Reasoning Engine For Verilog Via Abstract Interpretation, Alicia Thoney

Graduate Studies Theses and Dissertations 2026

Modern Electronic Design Automation (EDA) flows treat structural and semantic reasoning as separate concerns. Synthesis structurally optimizes RTL, while dedicated verification teams validate functional behavior through testbenches and formal methods. This organizational divide means designers have no automatic, sound way to understand what their RTL does at the moment they are writing it. This thesis introduces AbIG4L (Abstract Interpretation of Generic 4-valued Logic), a static analysis framework that bridges this gap by delivering sound semantic reasoning automatically, directly within the hardware design loop.

The framework operates on a language-agnostic intermediate representation to compute sound over-approximations of hardware behavior across 0, …


High Intensity Ablation By Laser Filaments At Standoff Distances, Owen Thome Jan 2026

High Intensity Ablation By Laser Filaments At Standoff Distances, Owen Thome

Graduate Studies Theses and Dissertations 2026

The high-power densities delivered to a target material by a laser allow for melting and vaporization to occur, a process called laser ablation. At higher intensities, plasma formation occurs and more complex material removal mechanisms take place. As laser power increases, nonlinear effects occur during propagation. One such effect, Kerr self-focusing, leads to beam collapse and ionization, resulting in a channel of plasma and region of high intensity light referred to as a laser filament. Filaments carry intensities on the order of 1013 W/cm2 to significant distances without the use of large-scale focusing optics. Laser filament ablation is …


Dynamic Interactions Of The Compressible Reacting Flow With A Morphing Wall In A Supersonic Combustor, Mason R. Thornton Jan 2026

Dynamic Interactions Of The Compressible Reacting Flow With A Morphing Wall In A Supersonic Combustor, Mason R. Thornton

Graduate Studies Theses and Dissertations 2026

The influence of compressibility on supersonic reacting flows is explored by varying the area expansion ratio in a supersonic cavity combustor using a moving wall. In principle, this design allows on-the-fly adjustment of the combustor aft wall expansion ratio to accommodate variable inlet conditions and fueling rates. The variable back pressure broadens the operability envelope and ensures greater pressure rise recovery compared with a constant geometry combustor. The results demonstrate that modulating area expansion alters the combustor pressure distribution and can influence cavity flame dynamics. At sufficiently high equivalence ratios and compression levels, the back pressure induced by the moving …


A Sensor Fusion And Optimization Framework For High-Resolution Power Outage Detection And Energy Asset Allocation, Elizabeth Trader Jan 2026

A Sensor Fusion And Optimization Framework For High-Resolution Power Outage Detection And Energy Asset Allocation, Elizabeth Trader

Graduate Studies Theses and Dissertations 2026

Existing power outage datasets lack the spatial and temporal resolution required for neighborhood- level risk assessment, and conventional energy system design optimizes for cost without accounting for community-level demand - resulting in inefficient and inequitable asset de- ployment. This dissertation presents IONCORTEX, a framework integrating three technical contributions: a heterogeneous sensor fusion pipeline combining social media signals with municipal infrastructure records for intersection-level outage detection at six-hour tempo- ral resolution, maintaining detection capability during telecommunications disruptions; a techno-economic analysis pipeline evaluating photovoltaic, battery storage, hydrogen, and diesel portfolios using NREL’s System Advisor Model with Monte Carlo uncertainty quan- tification; and …


Chirpi - Implementing And Analyzing The Chirp Communication Algorithm On Esp32 Hardware, Calvin Vanwormer Jan 2026

Chirpi - Implementing And Analyzing The Chirp Communication Algorithm On Esp32 Hardware, Calvin Vanwormer

Graduate Studies Theses and Dissertations 2026

This work presents the implementation and experimental evaluation of the CHIRP communication algorithm on resource-constrained ESP32-S3 microcontrollers, bridging the gap between simulation-based validation and real-world deployment. CHIRP is a lightweight, fully decentralized peer-to-peer protocol designed for IoT networks with dynamic node membership, enabling runtime node join and leave operations without centralized coordination or global reconfiguration. The implementation comprises two main components: C-based node firmware running on FreeRTOS [1, 2], which implements the full CHIRP protocol including peer discovery, round-robin pairing, and firefly-inspired phase synchronization, and a Python-based experiment controller that orchestrates network experiments and collects per-node metrics without influencing protocol …


Using Inferences From Natural Language Narratives To Improve Video Question Answering, Hoang Bao Truong Jan 2026

Using Inferences From Natural Language Narratives To Improve Video Question Answering, Hoang Bao Truong

Graduate Studies Theses and Dissertations 2026

The purpose of this thesis is to examine how structured narrative representation and reasoning strategies jointly affect the performance of Video Question Answering (VideoQA). Although recent advances in large multimodal and language models have improved video description and retrieval, causal and counterfactual reasoning remain challenging. This thesis studies an inference-only pipeline in which videos are converted into natural-language narratives, and those narratives may optionally be transformed into a structured NarrativeML format before multiple-choice questions are answered without task-specific fine-tuning. NarrativeML is a machine-readable narrative representation that explicitly encodes entities, events, and their causal and temporal relations. Three representational contexts are …


Watch Your Step, Mind The Crowd: Socially Compliant Navigation In Unstructured Environments, Jack Vice Jan 2026

Watch Your Step, Mind The Crowd: Socially Compliant Navigation In Unstructured Environments, Jack Vice

Graduate Studies Theses and Dissertations 2026

Autonomous mobile robots increasingly operate in complex real-world environments characterized by uneven terrain, dynamic obstacles, and human presence. This dissertation addresses the fundamental challenge of developing adaptive navigation strategies that enable robots to safely and effectively traverse unstructured outdoor environments including construction sites, agricultural fields, and disaster areas while maintaining social compliance around people. We advance this capability through five complementary contributions that collectively target dynamic, unstructured, human-occupied environments. First, we demonstrate evolutionary optimization of legged mobility for uneven terrain. Second, we propose using a spatiotemporal autoencoder to learn the temporal dynamics of moving people and objects. Third, we introduce …


Threads Of The Past: Exploration Of Banal Medievalisms In Russia's Invasion Of Ukraine, Evan Garrett Wallace Jan 2026

Threads Of The Past: Exploration Of Banal Medievalisms In Russia's Invasion Of Ukraine, Evan Garrett Wallace

Graduate Studies Theses and Dissertations 2026

This dissertation examines how medieval historical narratives circulate within contemporary Western digital discourse surrounding Russia’s invasion of Ukraine. Russian political rhetoric has frequently invoked the medieval polity of Kyivan Rus’ to assert civilizational continuity between the medieval past and the modern Russian state. While these claims have been widely discussed in political and media contexts, less attention has been given to how such narratives appear within everyday online discourse. This study investigates how medieval references are mobilized, circulated, and interpreted within social media environments during the early conflict.

The research draws on a dataset of approximately 160,000 tweets collected from …


Unmasking Pentastomes: Generating Genomic Resources For Enigmatic Parasites, Stephanie Lyn Villella Jan 2026

Unmasking Pentastomes: Generating Genomic Resources For Enigmatic Parasites, Stephanie Lyn Villella

Graduate Studies Theses and Dissertations 2026

The introduction of invasive species can disrupt ecosystems not only through competition and predation but also by introducing novel pathogens to naïve host populations. In the southeastern United States, the invasive Burmese python (Python bivittatus) has been implicated in the introduction of the pentastome parasite Raillietiella orientalis, which has been associated with increased parasite burdens and mortality in native snakes. Despite their ecological significance and ancient evolutionary history, pentastomes remain poorly represented in genomic databases, limiting efforts to understand their evolutionary origins, host–parasite interactions, and mechanisms underlying parasite emergence. This study addresses these gaps by generating the …


Dynamics Of Household Food Insecurity Vulnerability: Examining Health, Functional Limitations, And Income Stability, Renita Washburn Jan 2026

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 …


Invisible Stress, Visible Patterns: How The Superwoman Schema Shapes Diet And Feeding Practices In Black Mothers And Their Youth During The Summer Versus School Months, Jillian Weathington Jan 2026

Invisible Stress, Visible Patterns: How The Superwoman Schema Shapes Diet And Feeding Practices In Black Mothers And Their Youth During The Summer Versus School Months, Jillian Weathington

Graduate Studies Theses and Dissertations 2026

Background: Black mothers are frequently socialized into the Superwoman Schema (SWS), a coping pattern characterized by self-sacrifice and suppression of personal needs. Alongside significant caregiving demands, SWS may limit healthy eating opportunities, yet its relationship with diet quality (DQ) remains understudied. SWS may also intensify during unstructured summer periods. This study examined associations between SWS, perceived stress, and DQ among Black mothers and their youth during summer (T1) and school months (T2).

Methods: This observational within-subjects study included Black mothers (T1: n=51; T2: n=32; mean age 39.6±6.1) and their youth (mean age 10.6±0.3). Assessments occurred at two timepoints six weeks …


Oblique Detonation Waves In Internal Axisymmetric Converging Flow, Zachary P. White Jan 2026

Oblique Detonation Waves In Internal Axisymmetric Converging Flow, Zachary P. White

Graduate Studies Theses and Dissertations 2026

Detonative combustion offers significant thermodynamic advantages for high‑speed propulsion, motivating the development of detonation‑based combustors for hypersonic flight. Among these, oblique detonation wave (ODW) engines require extremely high combustor velocities to achieve steady wave stabilization. While most prior experimental and numerical studies have focused on planar two‑dimensional geometries, axisymmetric combustors offer practical benefits for hypersonic vehicle integration and may influence achievable pressure gain. However, the effects of inward‑turning axisymmetric compression on ODW formation and performance remain largely unexplored. This work presents an experimentally stabilized ODW formed on an internal axisymmetric converging ramp. Experiments were conducted in a high‑enthalpy blowdown wind …


Perceptions Of High School Students’ Sports Participation And Potential Impact On Post-Secondary Involvement, Anthony J. Wishart Jan 2026

Perceptions Of High School Students’ Sports Participation And Potential Impact On Post-Secondary Involvement, Anthony J. Wishart

Graduate Studies Theses and Dissertations 2026

This dissertation examined the shifting culture of youth sports in the United States and its impact on academic motivation among adolescent student athletes. The study utilized Self-Determination Theory (SDT) as a framework. Traditionally, youth sports have helped students with personal growth and academic success. However, the contemporary emphasis on early sport specialization and the decline of opportunities in nonrevenue male sports are part of broader cultural shifts and require deeper exploration.

This study investigated the relationship between sport specialization among high school male junior and senior student athletes and their levels of academic motivation, as well as the consequences of …


Sonic Costumes For Immersive Theme Park Storytelling: Developing Interactive Wearables To Enhance Performer, Audience, And Environment Interaction, Rachel Yee Jan 2026

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 …


Resources And Coping Strategies In Adverse Work Situations: A Person-Centered Approach, Chad Yagey Jan 2026

Resources And Coping Strategies In Adverse Work Situations: A Person-Centered Approach, Chad Yagey

Graduate Studies Theses and Dissertations 2026

The resilience process model highlights an approach to how people mobilize their resources to cope and positively adapt in the face of adversity. Leveraging Conservation of Resources (COR) theory and the Work Home Resources Model (WHRM), I aim to uncover the extent to which resilience capacity (resources) and resilience enactment (coping) influence outcomes of resilience, offering one of the first empirical tests of the resilience process model. Specifically, COR theory posits that the more psychological resources someone has, the more successful they are in coping. I challenge this notion by examining whether specific profiles of the combination of resources available …


Interactions Of Complement With Paramyxovirus Persistently Infected Cells, Nasser N. Yousef Jan 2026

Interactions Of Complement With Paramyxovirus Persistently Infected Cells, Nasser N. Yousef

Graduate Studies Theses and Dissertations 2026

Persistent RNA virus infections (PI) are often characterized by extended viral shedding and maintained cycles of inflammation. We have an incomplete understanding of interactions between exogenous and cell intrinsic Complement (C') factors and paramyxovirus PI cells. Parainfluenza virus 5 (PIV5) acute infected (AI) cells can be recognized and lysed by exogenous C’ factors, but PI cells become resistant to C’-mediated lysis. We hypothesized that the relative sensitivity of AI and PI cells to C’ lysis is correlated with viral glycoprotein expression on the surface of cells. PI cells display lower levels of viral glycoprotein expression compared to AI cells. Pharmacological …


Infrared Systems And Their Application On Target Detection And Geolocation, Li Zhang Jan 2026

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 Jan 2026

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 …


Bowtie Antenna-Coupled Bi₂Te₃–Sb₂Te₃ Thermoelectric Detector For Millimeter-Wave Radiation, Rumana Zahir Jan 2026

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 …


Voltage Stability Enhancement Of Large Load Interconnections Using Syncronous Condensers, Muhammad Ibrahim Abbas Jan 2026

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 …


Photothermal Excitation And Optical Interferometric Readout Of Mos2 Nanomechanical Resonators, Sadia Afrin Jan 2026

Photothermal Excitation And Optical Interferometric Readout Of Mos2 Nanomechanical Resonators, Sadia Afrin

Graduate Studies Theses and Dissertations 2026

Two-dimensional (2D) materials have emerged as promising candidates for nanoelectromechanical systems (NEMS) due to their exceptional mechanical, optical, and electrical properties. Among these materials, molybdenum disulfide (MoS2) has attracted considerable interest for nanomechanical resonator applications because of its low mass density, high mechanical strength, and semiconducting nature. This thesis presents the fabrication, theoretical modeling, and experimental characterization of suspended MoS2 drumhead resonators. The devices were fabricated by mechanically exfoliating MoS2 flakes from bulk MoS2 crystals and transferring selected flakes onto pre-patterned substrates using a dry-transfer process. Mechanical resonance was excited through photothermal actuation using a modulated blue laser, while device …


Cfd Analysis Of A Full Heat Exchanger Between Ammonia And Supercritical Co2 In Aviation Application, Mairah Ahmed Jan 2026

Cfd Analysis Of A Full Heat Exchanger Between Ammonia And Supercritical Co2 In Aviation Application, Mairah Ahmed

Graduate Studies Theses and Dissertations 2026

The aviation industry’s transition toward lower-carbon propulsion systems has accelerated interest in alternative fuels, including ammonia–hydrogen fuel blends. In this work, a supercritical CO2 Brayton cycle is integrated with the exhaust stream of a turbofan engine to recover waste heat and utilize it for ammonia preheating and cracking. The recovered thermal energy raises the ammonia temperature to the level required for catalytic decomposition, enabling onboard hydrogen production. The proposed architecture combines ammonia cracking with a high-bypass, two-shaft turbofan engine representative of the propulsion system employed on the Boeing 737 MAX 8. This approach addresses the challenges associated with onboard hydrogen …


Pseudo-Boiling Of Supercritical Co2 In A Parallel-Flow Microchannel And A Micro-Jets Impingement Device And Single-Phase And Two-Phase Heat Transfer Of Subcritical Co2 Jets, Pranzal Ahmed Jan 2026

Pseudo-Boiling Of Supercritical Co2 In A Parallel-Flow Microchannel And A Micro-Jets Impingement Device And Single-Phase And Two-Phase Heat Transfer Of Subcritical Co2 Jets, Pranzal Ahmed

Graduate Studies Theses and Dissertations 2026

Carbon dioxide (CO2) is gaining attention as a low-toxicity, zero-ozone-depletion refrigerant with a global warming potential of 1, making it an attractive alternative to synthetic HFCs/HFOs. Near its critical point, CO2's thermophysical properties change sharply with small shifts in temperature and pressure — a behavior that can be exploited to enhance heat transfer in trans-critical power cycles and electronics cooling. This dissertation experimentally investigates heat transfer during the pseudo-boiling of supercritical CO2 in a parallel-flow microchannel and a micro-jet impingement device, alongside CO2 flow boiling and single-phase water heat transfer in micro-jet impingement. Using microfluidic devices instrumented with embedded resistance …


Charge Transport Modeling Of Multifunctional Molecular Transistors, Romena Akter Jan 2026

Charge Transport Modeling Of Multifunctional Molecular Transistors, Romena Akter

Graduate Studies Theses and Dissertations 2026

Distinguishing between the current–voltage characteristic curves associated with different transport mechanisms in a molecular electronic device and an artifact arising from device-level disorder is a central challenge in the study of molecular electronics. Characterizing these mechanisms and connecting them qualitatively to molecular-level orbital alignment, electrode coupling, voltage division, energetic disorder, and reorganization energy requires not only experimental data but also a rigorous theoretical framework for extracting physically meaningful parameters from measured transfer characteristics. This dissertation addresses this challenge in Chapters 2, 3, and 4 by developing and applying four complementary transport models —Simmons tunneling, single-level Landauer, Marcus hopping, and McConnell …