Digital Commons Network^™

Fractals, Reachability, And Computation In Models Of Dna Self-Assembly And Chemical Reaction Networks, Ryan Arlie Knobel

Theses and Dissertations

This thesis serves as the bridge between results compiled across varying models of tile self-assembly, molecular computation, and game complexity. As such, this thesis is broken into three chapters. In the first part, we show how to generate any Discrete Self-Similar Fractal (DSSF) with a feasible generator in the seeded Tile Assembly model, a model limited to single tile attachments and pairwise state transitions. In the next part, we study models of molecular computation, where we consider the problem of reachability in Chemical Reaction Networks and similar model extensions. The final part is a game-complexity analysis of Celtic! and k-ago, …

Ai-Driven Electromagnetic Design And Performance Prediction Of Microstrip Antennas, Eduardo Javier Vazquez

Theses and Dissertations

This thesis investigates the application of Deep Learning to automate and accelerate microstrip antenna inverse design. The initial investigation was to predict microstrip antenna performance from its geometry parametric input, and found out that forward prediction with adopted geometric representation results in ill-posed scenario, high ambiguity and unstable mapping. The study later mostly focuses on the inverse prediction by machine learning from S11 parameter input to predict antenna patch geometry parameters instead.

A dataset of 5,000 ANSYS HFSS simulated antennas (later filtered to 4,136 valid samples) was generated using cubic spine -described geometry profiles. Multiple neural architectures were adopted for …

Boundary-Layer Mechanisms In Flow Over Triangular Porous-Textured Flat Plates: A Computational Fluid Dynamics Study, Luis Angel Alvarez

Theses and Dissertations

Growing demand for energy-efficient vehicles drives research into flow control strategies that mitigate aerodynamic drag. Active devices such as morphing flaps or plasma actuators offer real-time authority but require external power. Passive concepts, including riblets, tubercles, porous coatings, and miniature vortex generators, reshape the boundary layer without additional energy input. We propose an integrated passive solution called Triangular Porous Texturing (TPT). TPT combines the two mechanisms: a periodic array of triangular prisms that generate controlled streamwise vortices, and an embedded porous matrix that locally adjusts pressure gradients near the wall. Acting synergistically, these features attenuate near-wall turbulence, redistribute momentum, and …

Bacillus Subtilis: A Bacterium That Can Potentially Degrade Low-Density Polyethylene (Ldpe) And Polyethylene Terephthalate (Pet), Migdalia Flores

Theses and Dissertations

The widespread application and disposal of plastics, such as low-density polyethylene (LDPE) and polyethylene terephthalate (PET), have raised significant environmental health concerns. Because of each plastic’s stability and durability, these plastics exhibit limited natural degradation in the environment. Recently, the environmentally friendly biodegradation of plastics by living microorganisms has attracted more attention, as they can assist in the natural degradation process. In this study, the bacterial strain Bacillus subtilis ATCC6051 was used to degrade LDPE and PET for 60 days. To measure the degradation of low-density (LDPE) and polyethylene terephthalate (PET), the dry weight was taken, and physical characteristics were …

Development And Testing Of A Prototype Erbium-Doped Lithium Tantalate Based Sensor For Infrastructure Crack Detection And Measurement, Alejandro Barrera

Theses and Dissertations

Ensuring the safety and longevity of infrastructure is crucial to safeguarding communities and preserving economic stability. In this study, the development of a novel sensor for detecting and characterizing cracks in infrastructure, particularly suited for deployment on Unmanned Aerial Vehicles (UAVs), is presented. The device utilizes a laser (operating at 980 nm) for excitation of erbium-doped lithium tantalate nanoparticles that emit 1550 nm wavelength, which stimulates a photodiode for data collection. The data was utilized to collect, process, and reconstruct topological information. The synthesized lithium tantalate nanoparticle samples vary in erbium doping percentages of 0.5%, 3%, and 10%. Experimental evaluation …

Quantum Entanglement As A Resource For Coordinating Navigation, Aamir Ahmad

Theses and Dissertations

John Clauser, Michael Horne, Abner Shimony, and Richard Holt (CHSH) originally formulated the CHSH game as an experiment to establish entanglement as a quantum mechanical phenomenon that could not be predicted by classical theories. I will apply the quantum strategy used in the CHSH game to demonstrate that it also establishes a structure that employs entanglement as a resource to enable coordination without communication in the context of navigation.

Comparative Assessment Of Lower Limb Neuromusculoskeletal Activation And Joint Kinematics In Normal And Impaired Gait, Jack Ryan Schule

Theses and Dissertations

This thesis evaluates whether accessible and affordable technologies can provide clinically significant, quantifiable gait analysis comparable to traditional marker-based motion capture systems. Modern high-end systems offer excellent accuracy but remain financially and logistically inaccessible to many clinicians and researchers. To address this gap, a framework was developed using markerless pose estimation using the model, MediaPipe, inertial measurement units (IMUs) processed through an Extended Kalman Filter (EKF), and surface electromyography (sEMG) to measure joint kinematics and neuromuscular activity during gait. An experiment was performed where data was collected from participants with both normal gait and pathologies including: Osgood–Schlatter disease, Plica Band …

Towards Trustworthy Federated Learning, Alina Basharat

Theses and Dissertations

Federated learning is a collaborative training model in which multiple clients optimize aglobal model by transmitting updates to a coordinating server while keeping raw data on-device, thereby reducing direct data exposure and enabling iterative global improvement. However, the iterative communication process is vulnerable to malicious attackers that either deliberately destroy the model or curious to infer raw data. Moreover, learning from multiple agents may result in unfair results. To enhance trustworthiness within this setting, we employ two-sided norm-based screening (TNBS) that removes both abnormally large and abnormally small updates, pair it with a q-fair objective to emphasize high-loss (disadvantaged) clients, …

When Textures Trim Drag: Micro-Structures For Adaptive Drag Reduction And Flow Authority, Miguel Angel Olvera

Theses and Dissertations

Turbulent boundary layers are a major source of drag and performance loss. This thesis investigates Triangular Porous Texturing (TPT), apex-forward microstructures with optional bleed channels, as a passive concept for simultaneously reducing skin friction and strengthening boundary layer momentum near separation. Low-speed wind tunnel tests are conducted over tripped turbulent boundary layers on flat plates with three surfaces: a smooth baseline, a solid-crest TPT array isolating the knife-edge “slip-cut” effect, and a porous-bleed TPT array whose paired micro-channels vent a small fraction of the free stream. Time-resolved PIV provides wall-normal velocity fields; skin friction is inferred from near-wall shear, and …

Optimizing Pv Solar Array Design By Analysis Of The Industrial And Training Assessment Center (Itac) Database, Angel Samuel Fernandez

Theses and Dissertations

Since 2017, the Industrial Training and Assessment Center (ITAC) at UTRGV has included photovoltaic (PV) system evaluations in its industrial energy assessments. A review of these reports showed inconsistencies in PV system design, including variations in sizing methods, performance assumptions, and application of NEC requirements. To address these issues, this thesis develops a standardized and NEC-compliant methodology for designing PV systems, incorporating demand-based sizing, solar-geometry principles, and electrical calculations guided by NEC Articles 690 and 705.

This thesis focuses on demand-based PV system sizing and incorporates NEC-guided electrical design to ensure technical compliance and safety. System performance is evaluated using …

Training Aba Service Providers To Use Phonemic Transcription: A Comparison Of Two Alphabets, Kristin Marie Albert

Theses and Dissertations

Applied behavior analysis (ABA) service providers regularly develop speech and shape articulation when working with minimally vocal children with autism. However, these providers usually have not received training in related subject areas as part of their certification coursework. This results in a gap between their scopes of competence and practice. The present study aimed to lessen this gap by training ABA service providers to take phonemic transcription. The author, in consultation with a speech-language pathologist, developed and implemented a computer-based programmed instruction training package. Studies 1 and 2 employed a concurrent multiple-probe design with an embedded adapted alternating treatments design …

Examining The Relationship Between Title 14 Code Of Federal Regulations (Cfr) Part 147 Maintenance School Aviation Maintenance Technician (Amt) Instructor Experience And Instructor Pass Rates For Airmen Certification Standards (Acs) Element Subject Areas, Richard Lyman Johnson

Theses and Dissertations

This quantitative, correlational study examined the relationship between Aviation Maintenance Technician (AMT) instructor experience and student pass rates in 14 CFR Part 147 maintenance schools. Data were collected from February to August 2025 using purposive and snowball sampling, which yielded 67 complete responses. Instructor experience, measured in months of A&P-rated maintenance work prior to teaching, ranged from 1 to 684 months (M = 253.54, SD = 197.97). Student pass rates, defined as the proportion of students passing ACS element subject area courses, ranged from .52 to 1.00 (M = .95, SD = .07). Most instructors were male, White, over 50 …

Effect Of Capillary And Viscous Forces On Carbon Dioxide Desorption In Porous Adsorbent Layers, Caroline Isabel Mcclung

Theses and Dissertations

Temperature swing adsorption-based (TSA) carbon dioxide (CO₂) separation processes, which involve an alternating flow of gases and liquids in adsorbent-coated microchannels, have been shown to yield superior and environmentally friendly performance than the existing processes. This technique begins by sending the impure gas mixture through hydrophobic silicalite adsorbent-coated microchannels, which results in the adsorption of CO₂. Subsequently, hot water heat transfer fluid (HTF) flows through the same channels, displaces the purified gas stream, heats the adsorbent, desorbs the CO₂, and removes that desorbed CO₂ from the channel. This stage is followed by cooling …

Influence Of Peer-Led Team Learning In Students’ Chemistry Self-Efficacy, And Academic Achievement In General Chemistry Courses, Hector Leal

Theses and Dissertations

One of the most perplexing issues facing peer cooperative learning is dealing with student motivation and goal orientation. Sometimes the students who could most benefit from the positive effects of peer learning are the ones least likely to participate due to fear of exposing their academic weaknesses to others or even to themselves (Arendale, 2020). Exploring the complexity of student motivation is being carefully studied amongst elementary and secondary education student populations. However, this important construct is often ignored in the study of postsecondary education in general, and the provision of learning assistance, particularly at the college level. My purpose …

Cyberbullying And Mental Health Issues Among University Students, Brandi N. Cruz

Theses and Dissertations

According to the CDC (2024), bullying can lead to social and emotional distress, self-harm, and death. Bullying can also increase the risk for depression, anxiety, and poor academic achievement. The increased use of social media and the rise in cyberbullying (CB) and related mental health concerns among emerging adults is highly disconcerting, especially given their propensity for mental health problems. The purpose of this study is to increase the understanding of young university students’ perceptions about CB victimization and whether CB affects their mental health. A cross-sectional research design was used to conduct the study. In this study the number …

Performance Assessment Of Reconditioned Freight Rail Bearings Using Eddy Current Array For Enhanced Nondestructive Inspection, Eduardo Miranda

Theses and Dissertations

In North America, freight bearings removed from service must undergo a reconditioning process in accordance with Association of American Railroads recommended guidelines before reuse, with approximately 80% having been reconditioned at least once. This process includes bearing inspection, where repairable defects may be refurbished and returned to service with an extended performance range of 50,000 to 250,000 miles. Motivated by this extensive range in performance, researchers at the University Transportation Center for Railway Safety, in collaboration with MxV Rail, utilized a nondestructive evaluation method to enhance the reconditioning inspection process. An Eddy Current Array (ECA) was applied to bearing cup …

Modern Water And Sediment Transport Patterns In Alluvial Ridge Basins Of The Rio Grande Delta, South Texas, Usa, Waqid Nabi

Theses and Dissertations

Alluvial ridge (AR) basins are shallow, marine-influenced depressions within river deltas, yet their flow and sediment dynamics remain poorly understood. This study examines hydrodynamics and sediment transport patterns in the Bahia Grande Complex, which are AR basins of the Rio Grande Delta, using tilt current meters, water-level and turbidity loggers, and suspended and bed-sediment sampling. The AR basins function as wind-dominated, microtidal environments, where pre-existing basin geometry and hydrodynamic forcings control water flow and sediment distribution patterns. Seasonal wind patterns and storms modulate water levels and flow connectivity. Substrate patterns reflect frequent resuspension in the shallow northern basin, maintaining coarse …

Feature Extraction From Railroad Bearing Onboard Vibration Sensors Using Machine Learning Models, Diego Cantu

Theses and Dissertations

The University Transportation Center for Railway Safety (UTCRS) has developed an algorithm capable of identifying defective railroad bearings, determining damaged component(s) within, and quantifying severity of the defects. The defect-detection algorithm requires the operating speed as an input, which is not readily available in field operation of onboard sensors. Therefore, onboard sensors deployed in rail revenue service must rely on Global Positioning Systems (GPS) to obtain speed, which can be power-intensive and susceptible to signal interference. This study covers the development of a vibration-based model that extracts operating speed from wireless sensor data to enable fully autonomous onboard diagnostics. Signal …

Impacts Of Intensifying Wildfires On Boreal Forest Ecosystems: Exploring Forest Regeneration, Wildlife Habitats, Carbon Storage, And Engineering Solutions, Mckenzie Belle Schewe

Theses and Dissertations

Wildfire activity across Alaska’s boreal forests has intensified in severity and frequency in recent decades, altering one of Earth’s most significant sources of carbon sequestration (Pan et al, 2011). This thesis examines how wildland burns influence post-fire carbon sink capacities and vegetation recovery near Fairbanks, Alaska. Three fire sites were selected to represent distinct successional stages: the 2006 Parks Highway Fire, the 2013 Stuart Creek 2 Fire, and the 2022 Clear Fire. Each site was evaluated through a combination of remote sensing analysis, LiDAR-derived canopy height data, and field measurements collected within each burn perimeter, developing a replicable framework for …

Seasonal Performance Of Mrms Qpe In Urban Hydrologic Modeling Using Epa-Swmm, Randall Kirk Bagwell

Theses and Dissertations

Accurate rainfall estimation is essential for effective hydrologic modeling, particularly in urban environments where infrastructure must withstand extreme precipitation. This study evaluates the EPA Storm Water Management Model (EPA-SWMM) using MRMS RadarOnly Quantitative Precipitation Estimation (QPE) 1-hour Accumulation as the primary rainfall input for a watershed in Little Rock, Arkansas. The region was selected due to its urban character and the limited availability of radar-based hydrologic studies in Arkansas. 21 storms were analyzed from 2022-2025: 10 in Winter, 7 in Spring, and 4 in Summer. Storms were selected due to their effect on flow. The model was calibrated using February …

Control Strategy, Multi-Objective Optimization, And Economic Viability For Utility-Scale Wind-Solar-Based Hybrid Power Plant, Shree Om Bade

Theses and Dissertations

Hybrid Power Plants (HPP) that combine wind power plants (WPP), solar power plants (SPP), and battery energy storage systems (BESS) have recently emerged to provide dispatchable renewable electricity, improve the stability of the power grid, maximize use of infrastructure assets, and minimize carbon releases. Nevertheless, regardless of their technical potential, the large-scale application of HPP still encounters many barriers, such as operational complexity, inadequate sizing, and financial viability. To mitigate these issues, this study incorporates three research questions. First, this study introduces a four-layer hierarchical control architecture for coordinating WPP, SPP, and BESS to ensure dispatchable power. Second, a multi-objective …

Culture-Dependent Characterization Of Microbial Succession And Persistence In The Integrated Lunar/Martian Analog Habitat (Ilmah), Haley Olivia Boles

Theses and Dissertations

This study examines culture-dependent microbial monitoring in a closed lunar/Martian analog habitat, focusing on viable community dynamics relevant to long-duration missions. A standardized sampling and cultivation pipeline was implemented in ILMAH to track microbial succession and persistence under realistic operational conditions. Surface samples were collected across eight habitat zones at five mission timepoints (Days 0, 5, 10, 15, 20) during a 21-day crewed mission. Samples were concentrated post-collection and plated on chromogenic film media to quantify total aerobic bacteria (AC-R), fungi (YM-R), E. coli (EC), and S. aureus (SA). Plates were imaged and enumerated digitally; representative colonies were isolated and …

Spaceflight Safety Regulations: The Case For Implementing Safety Management Systems In The Developing U.S. Commercial Human Spaceflight Industry, Carly Davidson

Theses and Dissertations

Accidents have historically accompanied the development of new transportation systems, often due to technical failures; but human factors – such as organizational culture and management decisions – are increasingly recognized as significant contributors. A strong safety culture, prioritizing safety at all organizational levels, effective management procedures, and open reporting of violations, is believed to improve outcomes by proactively reducing risk in highly technical organizations. These elements form the basis of Safety Management Systems (SMS), which include safety policy, risk management, assurance, and promotion. As commercial spaceflight expands public access to space, US regulators must develop flexible safety regulations that protect …

Geochemical Characterization For Underground Hydrogen Storage (Uhs) In North Dakota's Red River Formation, Friday Obuzor Ebere

Theses and Dissertations

Hydrogen is advancing as a low-carbon energy carrier, necessitating storage to buffer supply-demand variability. Previous Underground Hydrogen Storage studies have not integrated experimental, geochemical, and numerical modeling approaches in a single investigation. This study integrates laboratory mineralogy, geochemical modeling and compositional simulation to assess underground hydrogen storage feasibility in North Dakota. Two settings were evaluated: depleted Red River carbonate reservoirs and an Inyan Kara sandstone aquifer. Thirty-seven core plugs underwent X-ray Diffraction/X-ray Fluorescence/Scanning Electron Microscopy characterization. Batch geochemical models (3,600 days) quantified hydrogen-rock-brine interactions. Field-scale simulations for Red River (~220 °F, ~3,000 psi) applied cyclic injection-withdrawal over 1,827 days (three …

Integrating Cognitive And Visual Scanning Strategies In Flight Instruction: Effects On Student Pilots’ Learning During Approach And Landing, Hyungwoo Jo

Theses and Dissertations

This interdisciplinary study employed a convergent parallel mixed-methods design to advance innovation in aviation education by incorporating eye tracking technology with enhanced performance traceability through visual modeling and comparative feedback. Specifically, the study investigated student pilots’ scanning behavior, cognitive strategies, and proficiency development on a normal approach and landing task by modeling flight instructors’ cognitive behavior. The first research phase revealed statistically significant differences in scanning ratios between 10 flight instructors and 10 student pilots along with substantial performance variation. The result showed that student pilots exhibited excessive outside fixation, often failing to monitor or respond to energy management in …

Dynamic Wellbore-Integrity Framework For Post-Blowout Capping Of Offshore Wells, Abdelhakim Khouissat

Theses and Dissertations

In the aftermath of a blowout, a well undergoes a period of unrestricted fluid discharge (de facto primary recovery) followed by pressure buildup after its shut-in, which can adversely impact wellbore integrity. The quintessential example is Union Oil’s 1969 “A-21” well blowout in California’s Santa Barbara Channel, where seafloor-broaching incidents (oil “boilups”) kept taking place from the sides of the well following several failed well-capping attempts, until reservoir depletion eventually allowed a successful shut-in.Analytical and numerical reservoir depletion models are coupled with near-wellbore geomechanics to quantify yardsticks related to the post-blowout discharge utilized to indicate dangers for underground blowouts, in …

Cross Cancer Toxicogenomic Modeling Of Arsenic Exposure Identifies A Four Gene Signature For Lung Cancer Risk, Joshua Kennedy

Theses and Dissertations

Arsenic is a naturally occurring carcinogenic element linked to DNA damage via reactive oxidation and epigenetic alteration that is ubiquitous throughout nature and has been associated with oncogenesis in the lungs, bladder, skin, and liver. Lung Cancer is both the most diagnosed cancer worldwide and the deadliest, comprising approximately 12.4% of all cancers globally and contributing to more human cancer death than any other condition, with roughly 90% of cases arising due to tobacco smoking, which exposes the user to arsenic trioxide and synergistic carcinogenicity when exposure includes both smoking and consumption of arsenic-contaminated drinking water. A novel set of …

Thermodynamic Evaluation Of The Thermal Methane Pyrolysis Process, Chinaecherem S. Okwuonu

Theses and Dissertations

Natural gas flaring is a persistent challenge which undermines global sustainability and decarbonization efforts as it leads to the waste of valuable energy resources alongside the release of harmful greenhouse gases into the environment. Even when natural gas is utilized through commonly adopted pathways, significant emission of carbon dioxide tends to be realized. Methane pyrolysis offers a promising route in which methane can be decomposed into solid carbon and hydrogen gas with no direct CO2 emissions. However, despite extensive studies of the methane pyrolysis process, a fundamental thermodynamic rationale of the process behavior remains insufficiently explored. This study 1) develops …

Methane Infusion Improved Oil Recovery In The Bakken Formation, Demetrius Maxey

Theses and Dissertations

This research establishes methane infusion improved oil recovery (MI IOR) as a technically viable and economically attractive early-stage intervention for unconventional reservoirs. Integrated multi-scale investigations included quantum molecular theory, nanoscale characterization, NMR experimentation, and field scale reservoir simulation. FEG-SEM analysis of core samples enabled development of a peer-reviewed pore size classification system informing MI operational design parameters. Integrated well logging quantified petrophysical properties across the Bakken stratigraphy. NMR relaxometry identified the lab-scale pore-level sweep efficiency of MI at 3,750 psi in Bakken core samples. Mobilization of hydrocarbons from Np1, Np2, and Np3 pores yielded recovery factors of 45-60%. Field-scale reservoir …

Optimizing Virtual Reality User Experience With Balanced Integration Of Quality Attributes, Ananth Ramaseri

Theses and Dissertations

This dissertation presents a real-time adaptive framework for mitigating cybersickness and enhancing user experience in virtual reality (VR) environments by dynamically adjusting key visual rendering parameters in response to users’ head movements. Conventional VR systems typically rely on fixed or manually configured settings that do not account for individual motion patterns or varying susceptibility to discomfort, leading to suboptimal usability and degraded immersion. In response, this work integrates software architecture tactics with data-driven machine learning models to proactively manage cybersickness while preserving rendering performance.

The proposed system employs a client–server architecture based on the Model-View-Controller (MVC) pattern. We conducted a …