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2026

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A Comparison Of Conversational Chatbots And The Internet For Consumer Information Search, Wondwesen Tafesse, Yoseph Mamo Jan 2026

A Comparison Of Conversational Chatbots And The Internet For Consumer Information Search, Wondwesen Tafesse, Yoseph Mamo

STEMPS Faculty Publications

This study compares consumer perceptions of conversational chatbots and the internet for information search. While the internet is a mature platform, conversational chatbots represent an emerging technology, and insight into how consumers view them in relation to the internet for information search is lacking. Drawing on the information source utility perspective, the study builds a comparative model based on four key dimensions: information currency, information customisation, information trustworthiness, and media richness. Additionally, the study investigates consumers’ prior experience with conversational chatbots as a moderating factor. Data was collected from 191 respondents recruited through MTurk. Paired sample t-tests assessed mean differences …


Crossing The Theory Threshold: The Pedagogical Potential Of Generative Artificial Intelligence In Educational Research, Amanda Burbage, Jennifer L. Styron Jan 2026

Crossing The Theory Threshold: The Pedagogical Potential Of Generative Artificial Intelligence In Educational Research, Amanda Burbage, Jennifer L. Styron

EVMS School of Health Professions Faculty Publications

Purpose

This paper presents findings from an educational research graduate course in which generative artificial intelligence (AI) was incorporated to strengthen learners' understanding of threshold concepts related to theoretical frameworks. Medical and health professionals often struggle with the transition from a clinical role into the educational research role.

Methods

The study posits that the use of generative AI will help learners understand and apply theoretical frameworks beyond a superficial level, furthering their understanding, constructing new knowledge, and strengthening their ability to develop sound educational research studies. Journal and AI transcripts were analyzed for 37 participants.

Results

Open-ended codes were grouped …


Walking And Wondering, Helen T. Tran Jan 2026

Walking And Wondering, Helen T. Tran

Theses and Dissertations

My thesis approaches walking as a form of inquiry and the Flood Wall as a site open to reinterpretation. I believe that the way we walk changes the way we observe and experience the world around us. This contrast between purposeful and leisurely walking reveals how time and intention shape our awareness of space. When walking is no longer dictated by urgency, it invites observations and questions. Slowing our pace allows curiosity to emerge, which aligns with my design ethos of asking questions as a foundation for understanding and creating meaningful experiences.

The Flood Wall’s emphasis on uninterrupted movement prioritizes …


Timing And Stability Of Uav Operations In Smart City Environments: Experimental Analysis And Design Implications, Rabia Ipek Yasar Jan 2026

Timing And Stability Of Uav Operations In Smart City Environments: Experimental Analysis And Design Implications, Rabia Ipek Yasar

Theses and Dissertations

This thesis investigates the deployment and performance of unmanned aerial vehicles (UAVs) within the Virginia Commonwealth University Open Cyber City (OCC) testbed. The study focuses on evaluating real-time indoor positioning performance using the Crazyflie drone platform. High-precision position measurements are obtained using the Vicon motion capture system, enabling analysis of the latency between the drone’s actual position and the system-reported position. In a closed-loop control system, the time difference between the position measurement and the application of the control command is called the system delay. Both stationary (hovering) and trajectory-following experiments are conducted to evaluate system performance. Communication delays in …


Participatory Systems Modeling In Implementation Research: Exploring Benefits, Facilitators, And Future Needs, Natalie Riva Smith, Jennifer L Cruz, Jessica Gannon, Stephanie Mazzucca-Ragan Jan 2026

Participatory Systems Modeling In Implementation Research: Exploring Benefits, Facilitators, And Future Needs, Natalie Riva Smith, Jennifer L Cruz, Jessica Gannon, Stephanie Mazzucca-Ragan

2020-Current year OA Pubs

BACKGROUND: Implementation science increasingly uses participatory systems modeling (PSM) approaches to handle the complexity inherent to implementation science issues. To support the process of integrating PSM with implementation science, we aimed to understand and explicate the benefits, facilitators, and future needs of applying PSM to implementation research.

METHODS: We conducted semi-structured qualitative interviews with 23 researchers (n = 18) and practitioners (n = 5). We purposively sampled participants and identified additional participants through recommendations. Interviews were inductively analyzed. Key concepts were identified via iterative description, comparison, and conceptualization.

RESULTS: Engagement with people in the system was typically focused in earlier …


Relationship Among Sleep Disturbance, Stress, And Suicidal Ideation In Clinical High Risk For Psychosis, Heather M Wastler, Daniel Mamah, Et Al. Jan 2026

Relationship Among Sleep Disturbance, Stress, And Suicidal Ideation In Clinical High Risk For Psychosis, Heather M Wastler, Daniel Mamah, Et Al.

2020-Current year OA Pubs

BACKGROUND AND HYPOTHESIS: Sleep disturbance is a well-established risk factor for suicide, though few studies to date have examined whether sleep disturbance contributes to suicide risk among individuals at clinical high risk for psychosis (CHR). The current study addressed this gap in the literature. We hypothesized that sleep disturbance would have a unique relationship with suicidal ideation/attempts when accounting for other variables in the model. We also hypothesized that the interaction between sleep disturbance/attenuated positive symptoms and sleep disturbance/stress would be related to suicidal ideation/attempts in CHR.

STUDY DESIGN: The current study used data generated by the Accelerating Medicines Partnership® …


Antihypertensive Medications And Risk Of Alzheimer's Disease: Evidence For Specific Medication Use, Osvaldo J. Laurido-Soto, Alejandra Camacho-Soto, Irene M. Faust, Kassu M. Beyene, Aaron Katz, Jordan A. Killion, Brad A. Racette Jan 2026

Antihypertensive Medications And Risk Of Alzheimer's Disease: Evidence For Specific Medication Use, Osvaldo J. Laurido-Soto, Alejandra Camacho-Soto, Irene M. Faust, Kassu M. Beyene, Aaron Katz, Jordan A. Killion, Brad A. Racette

2020-Current year OA Pubs

No abstract provided.


Generating Synthetic Ct From Mri Data, Foysal Ahmed Jan 2026

Generating Synthetic Ct From Mri Data, Foysal Ahmed

Theses and Dissertations

Magnetic resonance imaging (MRI) provides excellent soft tissue contrast without ionizing radiation, making it a strong alternative to computed tomography (CT) in medical imaging workflows. However, CT remains essential for applications requiring electron density information, such as radiation therapy treatment planning. This study investigated the feasibility of generating synthetic CT (sCT) images from MRI using a deep learning-based U-Net architecture. A two-dimensional U-Net was trained on paired MRI-CT data from the SynthRAD 2025 dataset, consisting of 120 T1-weighted (T1W) and 60 T2-weighted (T2W) axial cases, including deformed CT (dCT) aligned to MRI. Model testing used an independent dataset of 30 …


Impact Of Artificial Intelligence On Medical Education And Cognitive Skill Development At Medical College Imam Mohammad Ibn Saud Islamic University, Anas Bassam Barnawi, Abdulrahman Abdullah Almudawi, Abdullah Mohammed Alrabeah Jan 2026

Impact Of Artificial Intelligence On Medical Education And Cognitive Skill Development At Medical College Imam Mohammad Ibn Saud Islamic University, Anas Bassam Barnawi, Abdulrahman Abdullah Almudawi, Abdullah Mohammed Alrabeah

Health Professions Education

Purpose This study aims to explore the impact of AI on medical education by examining the relationship between AI use and academic performance in medical courses, evaluating the extent of its integration in students' clinical practice and application, and assessing how it enhances medical knowledge and understanding. In addition, the study measures medical students' attitudes toward the use of AI in their education and clinical training, providing a comprehensive overview of both its benefits and challenges.

Methods A cross-sectional survey was conducted between November 2024 and December 2024 with 168 participants, including students and interns from various academic years. The …


Turbine Exhaust Cylinder And Manifold Wake Interactions At High Swirl Angle, Christian A. Anzalotta Jan 2026

Turbine Exhaust Cylinder And Manifold Wake Interactions At High Swirl Angle, Christian A. Anzalotta

Graduate Studies Theses and Dissertations 2026

A commonly observed flow interaction in industrial gas turbine (IGT) exhaust diffuser configurations is investigated, where upstream structural wakes interact with downstream airfoil-like components, potentially leading to unsteady loading. To better understand the mechanisms contributing to this behavior, a scale-model is designed. Dynamic similarity is achieved by matching the Strouhal number (St) of the vortex shedding from the strut. A bell-mouth followed by a swirler is installed in front of the strut to mimic the flow angles at the inlet section of the turbine exhaust. Experiments are conducted for three swirl angles, namely, 30°, 45°, and 60°. Power spectra computed …


Viral And Host Cell Determinants Of Resistance To Complement-Mediated Killing During Parainfluenza Virus Type 5 Infection, Jenna R. Aquino Jan 2026

Viral And Host Cell Determinants Of Resistance To Complement-Mediated Killing During Parainfluenza Virus Type 5 Infection, Jenna R. Aquino

Graduate Studies Theses and Dissertations 2026

RNA viruses are a major global public health concern due to high mutation rates, zoonotic potential, and immune evasion. Parainfluenza virus 5 (PIV5) can establish persistent infections (PIs) despite encountering innate immune responses, including the complement (C′) system. RNA virus replication produces defective interfering particles (DIPs) containing truncated defective viral genomes (DVGs) that depend on standard (STD) virus for replication. DVGs are increasingly detected in natural infections and modulate type I interferon (IFN-I), but their role in the C′ system is unclear. We investigated how DVGs affect C′-mediated lysis during PIV5 infection using real-time in vitro cell viability assays. C′ …


First-Principles Insights Into Electronic And Magnetic Structure At Hybrid Interfaces And Low-Dimensional Materials And Reaction On Surfaces, Bushra Ashraf Jan 2026

First-Principles Insights Into Electronic And Magnetic Structure At Hybrid Interfaces And Low-Dimensional Materials And Reaction On Surfaces, Bushra Ashraf

Graduate Studies Theses and Dissertations 2026

Low-dimensional materials and transition metal surfaces/interfaces provide complementary platforms for understanding how dimensionality, symmetry, spin–orbit coupling (SOC), and interfacial charge transfer/hybridization jointly control electronic structure, emergent magnetism, and surface reactivity. Using first-principles modeling with experimental comparisons, this work aims to establish interfacial structure–property relationships across low-dimensional systems.

Strained Pd adlayers on 2H-MoS2(0001) provide a controlled platform to separate strain-driven exchange from interface-induced quenching in an itinerant d-electron metal. Although expansive strain promotes magnetism in free-standing Pd, strong Pd–MoS2 hybridization and charge transfer suppress the monolayer moment and leave a narrow thickness window where magnetism re-emerges in …


Restoring Digital Trust: Decentralized Frameworks For Identity, Consent, And Media Provenance, Raghu N. Avula Jan 2026

Restoring Digital Trust: Decentralized Frameworks For Identity, Consent, And Media Provenance, Raghu N. Avula

Graduate Studies Theses and Dissertations 2026

Digital platforms are deeply embedded in modern society through centralized network architectures. As online interactions transition to the physical world handling sensitive data, user privacy and cryptographic security require enhancement beyond traditional limits. This dissertation presents a decentralized “Tri-Layer Trust Architecture” that leverages Verifiable Trust Registries, Cryptographic Binding, and Edge Verification to prioritize data sovereignty and local authentication. To demonstrate the architecture’s applicability across distinct operational environments, we implement three solutions: (1) Verifiable Presence for peer-to-peer ride-sharing via D-RideX, which encrypts biometric data on physical hardware (TEEs) and Soulbound Tokens (SBTs) to prevent impersonation without cloud database exposure; (2) Verifiable …


Learning-Based Optimization For Collaborative Truck-Drone Routing And Scheduling, Ahmad A. Bany Abdelnabi Jan 2026

Learning-Based Optimization For Collaborative Truck-Drone Routing And Scheduling, Ahmad A. Bany Abdelnabi

Graduate Studies Theses and Dissertations 2026

Modern delivery networks increasingly rely on innovative technologies such as drones working alongside trucks to meet rising demands for fast and efficient last–mile transportation. Hybrid truck–drone delivery offers strong potential, but its effectiveness depends on careful synchronization between trucks and drones. Although drones provide fast, direct travel, their limited endurance and the need to coordinate launch and recovery with trucks create tightly coupled routing and scheduling interactions. Poor dispatch decisions can cause truck waiting, reduce parallelism, and increase mission completion time. These challenges motivate decision frameworks that explicitly model synchronization and develop scalable methods for coordinated truck–drone operations. This dissertation …


Understanding The Potential Biogeochemical Effects Of Alternative Restoration Materials: A Study Of Basalt And Other Materials, Cadie L. Barnes Jan 2026

Understanding The Potential Biogeochemical Effects Of Alternative Restoration Materials: A Study Of Basalt And Other Materials, Cadie L. Barnes

Graduate Studies Theses and Dissertations 2026

Concern over the effects of microplastics on estuarine ecosystems and public health has prompted many restoration practitioners to switch from plastic materials to more “natural” substrates. These natural (BESE-biopolymer, cement-jute structures) and non-plastic (basalt fiber) materials should not contain harmful substances; however, their chemical composition is unknown. Natural materials may degrade faster in subtropical environments and release nutrients into surrounding waters, which is concerning for eutrophic restoration areas. Basalt fiber bags, made from melted basalt rock spun into fibers, have not been evaluated for biogeochemical impacts within estuaries. To address this knowledge gap, two field experiments and two laboratory experiments …


Experimental And Numerical Study On The Stability Limits Of Ammonia And Ammonia/Hydrogen Flames Inside A Toroidal Jet-Stirred Reactor, Guillermo Alberto Barrios Cadenas Jan 2026

Experimental And Numerical Study On The Stability Limits Of Ammonia And Ammonia/Hydrogen Flames Inside A Toroidal Jet-Stirred Reactor, Guillermo Alberto Barrios Cadenas

Graduate Studies Theses and Dissertations 2026

Ammonia’s (NH3) properties as a carbon-free hydrogen carrier, its phase characteristics, and its wide global infrastructure present a solid case as a potential surrogate for carbon-based aviation fuels. Delivering a zero-emission NH3-based engine requires careful integration and optimization of the combustor and thermal management systems, a process that requires high-fidelity chemical reacting models experimentally validated through the use of simplified combustors. This study investigates NH3 fundamental combustion characteristics at conditions relevant to aviation gas turbines using a newly constructed toroidal jet-stirred reactor (TJSR) facility. Lean blow-off (LBO) experiments were carried out for NH3 blends …


The Dynamics Of Near-Limit Detonation Waves For Hypersonic Propulsion, Liliana Berson Jan 2026

The Dynamics Of Near-Limit Detonation Waves For Hypersonic Propulsion, Liliana Berson

Graduate Studies Theses and Dissertations 2026

The usage of detonation waves in hypersonic propulsion engines has seen substantial advancement in recent decades. The near-limit transition and failure process are key in these applications controlling the operability regime. The common cellular propagation of detonation waves fails in the near limit leading eventually to a singular transverse shock instability. The local dynamics of the wave causing this transition and the details of this singular instability remain a challenging question. These dynamics are examined in a fully automated detonation experiment using ultra-high-speed diagnostics and statistical analysis. Hydrocarbon fuel–oxidizer mixtures with nitrogen dilution are used to explore transition behavior over …


Assessing The Academic Performance Of Medical Students In Face-To-Face And Online Examinations: A Comparative Study From A Leading Medical College Of Peshawar, Pakistan, Rizwan Faisal, Iftikhar Qayum, Lia Anwar, Usama Afridi, Abdul Rahman, Rehan Ahmad Jan 2026

Assessing The Academic Performance Of Medical Students In Face-To-Face And Online Examinations: A Comparative Study From A Leading Medical College Of Peshawar, Pakistan, Rizwan Faisal, Iftikhar Qayum, Lia Anwar, Usama Afridi, Abdul Rahman, Rehan Ahmad

Health Professions Education

Background: The world of medical education is rapidly replacing the traditional face-to-face assessments of students by switching to online systems, and Pakistan is also undergoing this transition in its medical colleges and universities. It is therefore essential to obtain data on the performance of medical students in this new mode of assessment so that a smooth transition is enabled. Objective: To evaluate the academic performance of medical students in face-to-face and online examinations based on gender and professional year. Methods: A comparative study was performed at Rehman Medical College, Peshawar, Pakistan, from November 2023 to January 2024, on face-to-face and …


An Integrated Framework For Last-Mile Delivery Optimization Using Reinforcement Learning And Social Media-Based Traffic Prediction In Underdeveloped Megacities, Vasanth Bhat Jan 2026

An Integrated Framework For Last-Mile Delivery Optimization Using Reinforcement Learning And Social Media-Based Traffic Prediction In Underdeveloped Megacities, Vasanth Bhat

Graduate Studies Theses and Dissertations 2026

Supply chain management has become increasingly critical as transportation costs rise and urban delivery systems place additional pressure on already congested networks. Last-mile delivery—the movement of goods from distribution centers to end users—represents the most expensive and operationally complex segment of the logistics process, particularly in underdeveloped megacities characterized by unpredictable traffic, limited infrastructure, and sparse real-time data. This dissertation proposes an integrated framework for optimizing last-mile delivery in such environments by combining social media–based traffic intelligence, machine learning, and deep reinforcement learning. The framework leverages unstructured, real-time data from social media platforms to enhance traffic prediction and incorporates these …


Professional Identity Development Among Nursing Students: The Impact Of Structured Reflective Practice, Abdelmonim El Fadely, Kamal Takhdat, Charaf-Eddine Ahraiba, Rahma Bouali, Sabah Selmaoui, Boujemaa Agorram Jan 2026

Professional Identity Development Among Nursing Students: The Impact Of Structured Reflective Practice, Abdelmonim El Fadely, Kamal Takhdat, Charaf-Eddine Ahraiba, Rahma Bouali, Sabah Selmaoui, Boujemaa Agorram

Health Professions Education

Purpose This study aimed to assess the impact of a structured reflective practice intervention on the development of professional identity among nursing students. Method A mixed-methods design was adopted. The intervention, based on guided reflective practice, was implemented with a voluntary sample of 58 participants. The evaluation relied on a quasi-experimental quantitative approach using the Macleod Clark Professional Identity Scale, with a comparison group and both pre-test and post-test measurements. A qualitative component was also included to explore the dimensions of the studied concept in greater depth. Results Quantitative findings showed a statistically significant difference between the post-test means (p < 0.001), indicating that the reflective practice intervention had a positive effect on the experimental group compared to the control group. The qualitative results further illuminated students’ reflections, which were organized into ten themes corresponding to the study’s conceptual framework: professional knowledge and skills, values and ethics, the nursing role, leadership, professional self-image, social image of the profession, sense of belonging, identification with role models, theory–practice integration, and career choice. These dimensions provided a comprehensive and nuanced understanding of professional identity, capturing the complexity of the concept. Conclusion These results support the integration of reflective practice as a pedagogical approach to fostering the construction and development of a positive professional identity. Professional identity, as a rich and multidimensional concept, goes beyond the process of professionalization—it represents its ultimate achievement.


Investigation Of Exotic Phenomena In Topological Quantum Materials, Iftakhar Bin Elius Jan 2026

Investigation Of Exotic Phenomena In Topological Quantum Materials, Iftakhar Bin Elius

Graduate Studies Theses and Dissertations 2026

he First Quantum Revolution established quantum mechanics as the foundation of modern physics, enabling transformative technologies such as semiconductors, lasers, and transistors through prin-ciples of quantization, wave-particle duality, and uncertainty. The ongoing Second Quantum Rev-olution harnesses entanglement, superposition, and coherence to advance quantum computation, communication, simulation, and sensing. Central to this endeavor is the study of quantum mate-rials hosting novel electronic structures and emergent phases, including topological insulators and Dirac, Weyl, and nodal-line semimetals. In this thesis, using angle-resolved photoemission spec-troscopy (ARPES), transport measurements, and density functional theory (DFT) calculations, we investigate three classes of materials: (i) magnetic topological semimetals, …


Climate Change Education In Medical Curricula: Integration, Collaboration, And Preparedness For Emerging Health Challenges, Sungkono Sungkono, Agus Santoso, Firdiawan Ekaputra, Firdian Makrufardi Jan 2026

Climate Change Education In Medical Curricula: Integration, Collaboration, And Preparedness For Emerging Health Challenges, Sungkono Sungkono, Agus Santoso, Firdiawan Ekaputra, Firdian Makrufardi

Health Professions Education

Climate change poses increasing risks to global health, highlighting the need for healthcare professionals who understand the links between environmental change and health outcomes. Medical education is a key platform for fostering such competencies. This study aimed to examine the role of climate change education within medical curricula, focusing on its integration, the promotion of interdisciplinary collaboration, and its contribution to preparing students for emerging health challenges. This perspective paper provides an overview of current approaches to the integration of climate change education into medical training. Sources addressing curriculum design, knowledge acquisition, practical skill development, and collaborative learning were considered. …


An Algorithmic Framework For Polyhedral Gravity Modeling And Trajectory Propagation Near Small Bodies, Micah S. Boudreau Jan 2026

An Algorithmic Framework For Polyhedral Gravity Modeling And Trajectory Propagation Near Small Bodies, Micah S. Boudreau

Graduate Studies Theses and Dissertations 2026

Near-Earth asteroids (NEAs) and other irregular celestial bodies have become increasingly significant targets for scientific investigation and space mission development due to their relevance to resource utilization, origins-of-life studies, planetary defense, and understanding of early solar system formation. As launch costs continue to decline, missions such as NASA’s NEAR Shoemaker, OSIRIS-REx and JAXA’s Hayabusa series demonstrate the expanding feasibility of detailed small body exploration. Despite this growing interest, most standard astrodynamics tools are not designed to model the complex, highly irregular gravitational fields that are a signature of small bodies. Such limitations pose challenges for trajectory design, navigation, and control …


Computational Modeling Of Bubble Dispersion In Alginate Hydrogel Foams For Radiologically Equivalent Biomedical Phantoms, Godson N. Brako Jan 2026

Computational Modeling Of Bubble Dispersion In Alginate Hydrogel Foams For Radiologically Equivalent Biomedical Phantoms, Godson N. Brako

Graduate Studies Theses and Dissertations 2026

The foaming of hydrogels presents a promising strategy for tailoring mechanical and radiological properties to replicate biological soft tissues for biomedical phantoms. Achieving uniform and predictable void fraction distributions in alginate hydrogel foams remains a challenge due to the complex interplay between bubble dynamics, matrix rheology, and interfacial forces during the pre-gelation aeration stage. This thesis develops a Computational Fluid Dynamics framework using the transient Eulerian two-fluid approach to predict void fraction distribution in alginate hydrogel precursor solutions aerated by air injection through a bottom nozzle. The objective is to use the framework for design of the foaming system to …


The Bite Model And Multi-Level Marketing: How Monat Propagates, Lilly D. Cheung Jan 2026

The Bite Model And Multi-Level Marketing: How Monat Propagates, Lilly D. Cheung

Graduate Studies Theses and Dissertations 2026

This study aims to understand how MONAT Global Corp, a Multi-Level Marketing (MLM) company, utilizes rhetoric that aligns with Steven Hassan’s BITE Model of Authoritarian Control. Hassan is a cult expert and cult survivor whose work primarily explains undue influence and thought control with BITE representing Behavior, Information, Thought, and Emotional control. The MLM MONAT is a haircare brand that operates through a recruitment-and-sales-based hierarchy, in which sellers sign up and work under one another in a layered marketing structure. To meet quotas and maintain ranks, representatives will use rhetorical strategies to recruit new sellers beneath them in their ‘downline’ …


Enhanced Atomization And Combustion In Subsonic Ljic Systems Using Ultrasonically Driven Solid Obstructions, Daniel Sebastian Cruz Jan 2026

Enhanced Atomization And Combustion In Subsonic Ljic Systems Using Ultrasonically Driven Solid Obstructions, Daniel Sebastian Cruz

Graduate Studies Theses and Dissertations 2026

The liquid fueling methods used in aircraft propulsion have undergone extensive optimization, with Liquid Jets in Crossflow (LJIC) emerging as a simple yet effective injection scheme. LJIC enables sufficient fuel mass flow rates and penetration for high-speed operation, however fuel trajectory and droplet size remain highly sensitive to crossflow conditions. As a result, wide flight envelopes introduce variability in atomization, leading to unsteady combustion performance. Recent work has incorporated a pintile, a solid obstruction placed in the path of the fuel jet, to redistribute momentum and reduce trajectory variability across varying flow conditions. While this approach improves trajectory uniformity, it …


Detection And Discrimination Of Targets In Infrared Imagery, Adam T. Cuellar Jan 2026

Detection And Discrimination Of Targets In Infrared Imagery, Adam T. Cuellar

Graduate Studies Theses and Dissertations 2026

Automated infrared (IR) imagery analysis is essential for persistent surveillance, defense, and security, yet it remains difficult when sensors move and when unknown objects appear. This dissertation addresses two fundamental problems: (1) detecting small moving targets amid platform-motion induced parallax and (2) distinguishing between known stationary targets and out-of-distribution (OOD) objects.   For detecting moving targets while the platform itself is in motion, auxiliary Global Positioning System and Inertial Navigation System data are combined with image analysis. Direction Cosine Matrices from calibrated inertial measurements enable sub-pixel frame alignment unattainable with purely image-based registration. The stabilized sequence is processed by a Reed–Xiaoli …


A Framework For Optimizing Creep Model Parameters From Conventional And Accelerated Creep Tests, William D. Day Jan 2026

A Framework For Optimizing Creep Model Parameters From Conventional And Accelerated Creep Tests, William D. Day

Graduate Studies Theses and Dissertations 2026

The demand for efficiency in power generation and propulsion requires higher firing temperatures and reduced cooling air consumption which raises metal temperatures. This makes simplistic creep evaluations, such as Larson-Miller and Orr-Sherby-Dorn parameters, inadequate. Finite element analysis (FEA) must simulate primary and secondary creep, predict failure, and provide design guidance. Gas turbine components, expected to last over 100,000 hours, often require extrapolation of limited test data for new materials. It is essential that robust creep simulations be developed efficiently, accurately, and effectively use limited test data.

This dissertation describes an optimized framework for efficient creep testing and rapid construction of …


A Reconstruction Method For The Anisotropic Electrical Conductivity In A Hybrid Planar Inverse Problem, Athanasios Dimitriadis Jan 2026

A Reconstruction Method For The Anisotropic Electrical Conductivity In A Hybrid Planar Inverse Problem, Athanasios Dimitriadis

Graduate Studies Theses and Dissertations 2026

Some single-physics medical imaging methods fail to reliably discriminate benign from malignant biological tissue. In partial response, a new class of inverse problems employ multi-physics phenomena, coupling methods of high resolution with methods of high contrast. In this thesis we are concerned with one such problem in which an anisotropic electrical conductivity is to be recovered from some internal knowledge of the current density field generated by maintaining a fixed boundary voltage. This internal data is obtained by the method of Current Density Impedance Imaging (CDII), which combines Maxwell's equations with Magnetic Resonance Imaging (MRI) measurements. The anisotropy class is …


Temperature And Speciation Measurements Of Aluminum-Laden Detonation Flows Via A Three-Color Wavelength Modulation Spectroscopic Sensor, Marc B. Etienne Jan 2026

Temperature And Speciation Measurements Of Aluminum-Laden Detonation Flows Via A Three-Color Wavelength Modulation Spectroscopic Sensor, Marc B. Etienne

Graduate Studies Theses and Dissertations 2026

Tunable diode lasers are widely used and are known to be great options for continuous wave lasing applications. Because of their stability and spectral selectivity, they have become an important diagnostic tool for modern combustion research. Previous combustion research, particularly those focused on solid and hybrid rocket systems, have shown that the interaction of aluminum with a reacting flow can greatly affect the dynamics and the thermochemical properties of the surrounding gas, therefore understanding the effects of aluminum-laden flows is critical for the advancement of these propulsion systems. However, due to the high degree of optical interference, high temperatures, and …