Digital Commons Network^™

Design And Simulation Of Anti-Resonant Hollow-Core Fiber For Sensing Applications, Pravallika Kante

Theses and Dissertations

This thesis presents the design and simulation of an 8-tube single-ring anti-resonant hollow-core fiber for sensing applications, with particular emphasis on methane gas detection at the fundamental absorption wavelength of 3.3 µm. Conventional solid-core silica optical fibers exhibit strong multi-phonon material absorption beyond 2.5 µm, rendering them fundamentally unsuitable for efficient light guidance and direct gas sensing at mid-infrared wavelengths. Anti-resonant hollow-core fibers overcome this limitation by guiding light predominantly through an air-filled hollow core via the anti-resonant reflecting optical waveguide mechanism, in which the thin silica glass walls of the cladding tubes act as Fabry-Pérot etalons that confine the …

Quantifying Noise In Monte Carlo Simulations Of Cosmic Rays In A Shock, Abhro Rahman

Theses and Dissertations

Cosmic rays are a phenomenon known to humankind from the early 1900s, and yet today the details of their physical behavior are not fully settled. While the observed spectral fluxes of cosmic rays follow a power-law trend when plotted against particle energy, the exact mechanisms under which they get to such high energies are still under study. This thesis will undertake a subsection of that task, where the Monte Carlo simulation of particle accelerations is described in Warren (2015), and we aim to identify and quantify the noise inherent in such simulations. This document takes a long path through particle …

Hybrid Machine Learning For Zero-Day Malware Detection: An Adaptive Static-Dynamic Analysis Approach, Garrett Farmer

Theses and Dissertations

In an era of swiftly evolving cyber threats, zero-day malware continues to be one of the most challenging classes of attacks to detect and mitigate. Traditional signature-based methods often fail to detect novel malicious code, leaving institutions vulnerable to unknown exploits. This thesis proposes a machine learning (ML)-based framework that is designed to detect unknown malware variants. By combining both static and dynamic techniques, such as file structure exam ination and sandbox-based runtime analysis, this approach aims to successfully capture malicious characteristics. The proposed custom pipeline addresses the computational overhead that is associ ated with deep inspections, outlining a staged …

Moon Adaptive Technology For Extraterrestrial Architectural Robotics (Matear), Candela Noemi Solis Zampini

Theses and Dissertations

The Moon Adaptive Technology for Extraterrestrial Architectural Robotics (MATEAR) focuses on the development of an autonomous robotic system capable of providing structural building blocks directly from lunar regolith. As a sustained human presence on the Moon becomes a necessity, the costly and limited payload capacity associated with transporting construction goods from Earth creates a critical challenge. MATEAR addresses this problem through in-situ resource utilization (ISRU), integrating a regolith processing system onto a remote operated vehicle. The proposed system is designed to collect lunar dust, mechanically compact the material, and apply thermal treatment to enhance cohesion through sintering. These regolith-made bricks …

Voices From The Classroom: Elementary Teachers’ Perspectives On Teaching And Learning During The Covid-19 Pandemic – A Case Study And Autoethnography, Alicia Lopez-Hernandez

Theses and Dissertations

Guided by constructivist learning theory and sociocultural theory, this qualitative case study and autoethnography examines how bilingual educators constructed knowledge, adapted instructional practices, and utilized mediational tools within face-to-face, online and hybrid learning environments. These frameworks informed the study’s design, data analysis, and interpretation of findings related to pedagogy, technology integration, and student engagement. Data was collected through semi-structured interviews, naturalistic observations, and autoethnographic reflective journaling.

Elementary Teachers' Culturally Responsive Strategies For Fostering Critical Thinking In Science Instruction With Emergent Bilinguals, Lydia Stella Ratel

Theses and Dissertations

This phenomenological study explored the lived experiences of bilingual and English as a Second Language (ESOL)-certified elementary teachers as they fostered critical thinking among emergent bilingual (EB) students in grades 3–5 science classrooms. Grounded in culturally responsive pedagogy, translanguaging, funds of knowledge, and critical thinking theory, the study examined how teachers made sense of instructional decision-making and EB students’ scientific reasoning within accountability-driven educational contexts.

Data were collected through in-depth, semi-structured interviews with elementary teachers serving emergent bilingual students in South Texas public schools. Phenomenological analysis was used to identify shared meanings across participants’ descriptions of instructional practices, language use, …

Exploring Servingness Through Pedagogy: A Critical Case Study Of An Hispanic Serving Institution, Yemin Sánchez

Theses and Dissertations

This critical ethnographic case study advances current understandings of what it means to teach at an Hispanic Serving Institution (HSI) and how faculty enact servingness within an HSI enrolling high indices of Latin@/Hispanic students. Drawing on decolonial, culturally sustaining and liberatory pedagogical frameworks, this study interrogates how constructs such as Hispanic, Latin@/Latinx, or coloniality shape the pedagogical conditions under which faculty operate. Using pláticas with ten faculty members, this research study demonstrates servingness is not a technique or an institutional designation, instead, it is a fluid and deeply humanizing ecology with five mutually reinforcing dimensions: Servingness as Relational Praxis, Servingness …

Analyzing Criteria Air Pollutants And Meteorological Parameters In The Rio Grande Valley, Laredo, And Corpus Christi Region Of South Texas, Angela Garcia

Theses and Dissertations

Recently, the Rio Grande Valley has experienced significant population growth due to economic opportunities, cross-border commerce, SpaceX, and the Rio Grande and Texas liquid natural export terminal presence. The Rio Grande Valley has an estimated population of 1,368,723. This region is largely understudied, along with nearby urban centers such as Laredo and Corpus Christi. The Rio Grande Valley and Laredo regions are a concern due to their population growth and heavy cross-border transportation. Data from the Texas Commission of Environmental Quality Continuous Ambient Monitoring Sites was collected from January 1st , 2024, to December 31st, 2024. Statistical analysis, such as …

Vision-Language Guided Quadruped Navigation With Reinforcement Learning Control, Chen Yuan Wang

Theses and Dissertations

Large Language Models and their multimodal variants, Vision-Language Models (VLMs), can interpret natural language instructions and visual context. Reinforcement Learning (RL) methods such as Proximal Policy Optimization (PPO) have been shown to successfully learn stable quadruped locomotion. This work investigates whether a VLM integrated with an RL controller can control a quadruped robot to perform instruction-following navigation to a predefined target using text instructions, egocentric vision, and proprioceptive state.

Most VLM-based robotics work directly target prediction of robot actions from multimodal inputs. This approach often depends on large amounts of expert demonstration data, generated by controllers such as trained RL …

Engineering Translational Biosensing Tools Forparkinson’S Disease, Mercedes Terry

Theses and Dissertations

Parkinson’s disease is a progressive neurodegenerative disorder characterized by motor dysfunction and early cognitive decline. Diagnosis and monitoring remain largely symptom-driven, relying on clinical scales that capture disease only after significant neurodegeneration has occurred. These assessments are inherently subjective, episodic, and insensitive to early-stage pathology, limiting both timely diagnosis and the ability to track disease progression or therapeutic response. The lack of objective, quantitative biomarkers for both molecular pathology and cognitive impairment remains a major barrier to advancing precision medicine approaches in Parkinson’s disease. This dissertation approaches Parkinson’s disease from two complementary fronts: molecular detection of alpha-synuclein pathology and quantitative …

Machine Learning Applications For Numerical Simulation Of Co2 Sequestration, Adeboye Kayode Adeyinka

Theses and Dissertations

Global CO2 emissions significantly exceed the capacity of planned sequestration projects. Among subsurface storage sites, deep saline aquifers offer the largest theoretical capacity because they occur naturally across most sedimentary basins. However, major geological uncertainties, such as permeability variations and sand continuity, complicate these projects due to sparse well data. Consequently, analyzing CO2 sequestration projects in saline aquifers require robust reservoir simulation which are unfortunately, computationally complex with long runtimes, presenting severe bottlenecks for extensive risk assessment.

Machine learning algorithms can overcome these limitations by drastically reducing computational runtimes, enabling rapid scenario testing and optimization. Despite this potential, existing literature …

Porous Hydrophobic Adsorbent Coatings For Carbon Dioxide Capture, Samuel Babatunde Olushola

Theses and Dissertations

This work presents the development of a porous, hydrophobic zeolite 13X coating for the separation of carbon dioxide (CO₂) from flue gas or natural gas. Zeolite 13X was combined with yeast, glucose, and sodium alginate as pore-forming agents, and with polytetrafluoroethylene (PTFE) and Polydimethylsiloxane (PDMS) as hydrophobicity-inducing agents to enhance water resistance while maintaining CO₂ access to the adsorbent. The study explored PTFE/13X mass ratios ranging from 0 to 2.33 to investigate the interplay between hydrophobicity and CO₂ uptake. The wettability of the coating was characterized by using a temporal water contact angle (WCA) measurement. Increasing …

The Effects Of Self-Management On Portion Control Consumption In A Natural Setting, Amber Nicole Lampert

Theses and Dissertations

Obesity is a significant public health concern, with overeating as a primary contributor. Despite national nutrition initiatives, most Americans consume inadequate amounts of fruits and vegetables while exceeding recommended portions of calorie-dense foods. Understanding food groups and recommended portion sizes of each may be a prerequisite skill for a health initiative aimed at weight loss. Given that environmental and behavioral factors influence eating behaviors, Applied Behavior Analysis (ABA) offers an evidence-based framework for improving nutritional habits through self-management interventions. This study examined the effects of self-management components on portion control within a natural eating environment. Four adult participants, one male …

Foreign Language Experience Effects On L2-Accented Speech Attitudes In College Students, Jordan L. Ellington

Theses and Dissertations

The purpose of the study is to test whether knowledge of a second language in college students can affect perceptions and prejudices towards speakers with foreign accents. The testing was completed through both implicit and explicit attitudinal measures in regard to recorded audio stimuli. The explicit attitudinal testing was performed through participant self reporting of attitudes. Participants were presented with first (L1) or second (L2) language accented English samples and then rated that speaker in terms of various characteristics or traits that represented the speaker's solidarity and status. The implicit testing was performed in an Auditory Implicit Associations Test on …

Differentiable Objectives For 3d Scene Relighting Via Gradient Descent On Olat Basis Coefficients, Anson Savage

Theses and Dissertations

Designing effective lighting is an iterative and often time-consuming process. This work contributes to automatic lighting design research by presenting a render-engine agnostic optimization routine: gradient descent on RGB multipliers of one-light-at-a-time (OLAT) basis images. We compare several objective functions to accomplish lighting tasks and show that our method is capable of quickly and effectively exploring different lighting styles using either text prompts or reference images. We also present several datasets specific to lighting tasks and show that fine-tuning on these datasets can improve performance.

Advanced Studies In Characterization Of Pyrolysis Products From Live Vegetation, Mahsa Alizadeh

Theses and Dissertations

Fire is a naturally occurring element in many ecosystems which can have both positive and negative effects. However, in recent years the frequency of the fires and the area they affect has increased. The rapid spread of wildland fires coupled with the limited resources available to forest services to manage wildland fires highlights the urgency for accurate prediction of fire spread. Fire prediction models enable the fire management services to predict the spread of fire and prioritize firefighting efforts more effectively. Understanding reactions and mechanisms occurring during wildland fires improves the fire prediction models. During wildland fires, the biomass covering …

Improving Electrochemical Measurements And Informing Future Reprocessing Of Advanced Nuclear Fuels, J. Marvin Torrie

Theses and Dissertations

This research promotes the application of molten salts through developing analytical tools in electroanalytical studies and in the data analysis of vapor pressure data. The electrochemical community lacks standardized, stable, and repeatable reference electrode designs which threaten the reliability of measured thermophysical properties and repeatability of published studies. This work confirms the application of a saturated reference electrode design for molten chlorides systems that outperforms traditional Ag+/Ag reference electrodes. In the field of thermal physical property measurements, vapor pressure data for chloride salts are diffused throughout the literature, uncertainty quantification is absent or limited, and all previous studies rely on …

These Wretched Waters: A New Perspective On The Myth Texts And Visual Adaptations Of The Danaids, Tessa Haney

Theses and Dissertations

Both Greek and Latin texts regarding the Danaids are rife with gestational imagery and vocabulary. This textual focus on chthonic, symbolic aparturience coheres with both Greek and Roman perceptions of femininity. Women in both cultures were socially mandated to marry, have children, and confine themselves to the domestic sphere. The Danaids’ refusal to participate in this system would have been viewed as a breach of cosmic order, and a punishment that grounded the sisters in their 'traditional’ femaleness would have been viewed as a solution to such a breach. While early modern visual adaptations of the Danaid myth lack gestational …

Robust And Interpretable Cross-Domain Arabic Readability Prediction Using Hybrid Modeling: Evidence On The Limitations Of Transformer-Based Classifiers, Sarah Alzu'bi

Theses and Dissertations

Automatic readability assessment aims to predict how difficult a text is for readers to understand. The concept of readability has been widely studied across languages due to its significant impact on reading comprehension, leading to the development of various methods and approaches. In this study, I addressed two key challenges in readability assessment. First, I examine the performance of statistical classifiers and transformer-based models, including CAMeLBERT(Inoue et al, 2021.) with a focus on their ability to generalize under domain, genre, and stylistic shifts. Second, I investigate the interpretability of transformer performance in readability task, which are often criticized for their …

Independent English Teaching In Brazil: A Case Study, Jade G. Gunca

Theses and Dissertations

This qualitative case study investigates the experiences and practices of successful independent English as a Foreign Language (EFL) teachers in Brazil who operate outside traditional schools and private language institutes. Rather than providing a broad descriptive profile, this study offers an in-depth examination of a small group of teachers. These educators frequently use social media platforms such as Instagram and Facebook to showcase communicative, personalized, and flexible instruction in response to growing learner demand. Although English is widely taught in Brazilian schools, persistent structural constraints often limit students’ development of communicative proficiency, prompting some learners to seek instruction from independent …

A Masked-Perturbation Model For Destabilization Security Games In Feedback Systems, Gabriel Michael Perry

Theses and Dissertations

In this thesis, we present a mathematical formulation for increasing cyberphysical system security. This model allows a system administrator to use assumptions about exposed signals to derive defense strategies meant to mitigate the system's vulnerability to feedback perturbation attacks. We begin with a survey of game theory with the goal of building the concepts of resource and security games. We then introduce our model, which is a security game; targets in this game are exposed signals in the model map of the system, and resources are perturbed or introduced dynamical relationships between these signals. This formulation, called the masked-perturbation model, …

Studies On The Contribution Of Osh6 To The Functions Of Late Endosomes, William King

Theses and Dissertations

The late endosome (LE) is a hub organelle connecting endocytic, biosynthetic, exocytotic, and autophagic vesicle traffic pathways. Malfunctions of LEs are associated with multiple age dependent diseases such as Parkinson’s disease (PD). Despite this significance, how cells refurbish lipids and proteins to LEs to maintain their sustained activities are not clear. Previous studies in the model organism budding yeast show that up-regulation of a lipid transporter Osh6 (PERG6-OSH6) accumulates phosphatidylinositol-4-phosphate (PI4P) on the trans-Golgi network. It also promotes vacuole fusion and maintains the robustness of vacuoles in aged cells. Since LEs are the organelle between the TGN and vacuoles in …

Improving Reclamation Seeding Success Through Seed Technologies, Surface Preparation, And Microbial Inoculants, Josh M. De Santiago Lazalde

Theses and Dissertations

Revegetation of reclaimed lands is often limited by poor seed placement, unfavorable surface conditions, and reduced biological activity, particularly on steep or physically degraded substrates where broadcast seeding is commonly used. Improving early seeding establishment under these conditions requires approaches that address both physical and biological barriers to seedling development. We evaluated the effectiveness of surface preparation, seed technologies, and microbial inoculants for improving plant establishment in field and greenhouse settings relevant to mineland reclamation. At the field scale (Chapter 1), we investigated the effects of chain harrowing and seed enhancement treatments on the establishment of grasses, forbs, and shrubs …

Mild Thermal Treatment Of Lithium-Ion Batteries To Optimize Black Mass Production, Brooke Lillie

Theses and Dissertations

This thesis explains the design of equipment and the experimental procedure for thermal treatment of lithium-ion batteries for the purpose of low-cost materials recycling. Conditions used were between 150 ℃ and 425 ℃, involving different atmospheric conditions and treatment durations. The battery samples were processed through a sieve shaker device. Mass loss during the heat treatment, and separation of the battery through sieving was used to analyze the effect of the treatments on separability of black mass from the batteries. Additionally, internal battery temperature was measured and compared to real average furnace temperature to monitor thermal runaway. Testing showed minimal …

Some Closure On The Relation Between Cfg And Peg, Nathan J. Bulloch

Theses and Dissertations

We work toward a practical, unified language formalism for structurally recursive languages by expressing the mathematical theories underlying context-free grammars with lookahead (CFGLA) in the Rocq theorem prover and leveraging CFGLA semantics to analyze interactions between between recursion and negative lookahead. We give examples of grammars with left-recursive negation cycles for the parsing expression grammar (PEG) variant due to Medeiros et al. and for the translation from PEG to CFGLA due to Miyazaki and Minamide. To study the interaction between left recursion and negative lookahead in a PEG context, we introduce FPEG, a left-recursive extension of PEG with Fitting semantics.

Biomass Fuel Processing, Mineral Matter Engineering, And Ash Phase Equilibria For Deposition Control In Coal To Biomass Boiler Conversion, Spencer Bandi

Theses and Dissertations

As the conversion of coal utility boilers to 100% biomass combustors gains traction, understanding the interconnected impacts of harvesting and storage methods, fuel preparation, and thermochemical ash behavior is critical. This study evaluates miscanthus, switchgrass, and corn stover, targeting a < 1000 µm particle size through minimal (shredders/hammer mills) and heavy (pelletizing) pre-treatment. While heavy pre-treatment failed in a coal mill, minimal pre-treatment succeeded. Miscanthus (forage-harvested/silage-bagged) proved optimal, exhibiting minimal exogenous mineral accumulation up to (1.26 w%) and the smoothest mechanical feeding (deviation < 9%) due to its low particle aspect ratio. Conversely, baled switchgrass and corn stover accumulated up to 9.23 w% mineral matter and exhibited severe feeding resistance (>17% deviation) driven by fibrous, high-aspect-ratio morphologies. During combustion, agricultural residues yield low ash fusion temperatures (AFTs), generating deposits two to three times stronger than coal. To mitigate this severe fouling, mineral additives (coal fly ash, lime, and cement kiln dust) were injected. These additives effectively raised bulk AFTs and reduced deposit tenacity by up to 73%. Specifically, 2 w% …

Silicon Dioxide Multimode Interferometer Spectrometers, James Harkness

Theses and Dissertations

Multi-mode interferometer (MMI) spectrometers are a type of reconstructive micro-spectrometer based on imaging light propagation patterns in MMI waveguides. This dissertation describes how the MMI spectrometer was implemented for the first time using a silicon dioxide core. This approach showed a 6 dB improvement in SNR over SU-8 core devices. To implement the silicon dioxide MMI spectrometer, a fabrication technique for selectively roughening the surface of the waveguide needed to be developed. SU-8, a photosensitive polymer, was etched with oxygen plasma to create grass-like nanostructures. SU-8 grass can then be used as a transfer mask to plasma etch a surface. …

An Examination Of K-12 Administrators' Philosophical Views On Music Education, Kathryn Ann Smith

Theses and Dissertations

K-12 administrators' beliefs about the purpose and value of music education have resulted in inconsistent support for students' access to music education in public schools. This study sought to examine administrators' philosophical views about music education and factors that may influence those beliefs, contributing the first known application of a praxial framework in assessing administrator belief systems. I developed a survey incorporating Song's (2025) Philosophical Beliefs Scale (Ph.B. Scale) to measure utilitarian, aesthetic, and praxial philosophical perspectives, along with key demographic and contextual characteristics. Participants (N = 65) were recruited via e-mail and K-12 administrator Facebook groups and represented a …

Tracing Microplastics From Polymer-Coated Urea: Urban To Agricultural Pathways And Environmental Fate, Caden Joseph Seely

Theses and Dissertations

Polymer-coated urea (PCU) is widely used as a slow-release nitrogen (N) fertilizer because it improves N use efficiency and reduces losses through leaching, denitrification, and volatilization. However, the polymer coating raises concerns about potential microplastic (MP) transport to surface waters following fertilizer application. This thesis evaluates the off-site transport of MPs and associated nutrient and sediment losses from PCU in both urban landscape and agricultural systems. In the urban landscape study, treatments included sod, mulched beds, and water-efficient ground cover receiving uncoated urea, PCU, or liquid slow-release N at 225 kg N ha⁻¹ (with reduced rates for beds and ground …

Stack-Based Exploit Development Techniques In Mips Architectures, Justin Applegate

Theses and Dissertations

Memory corruption vulnerabilities in binary executables represent a serious threat to software security, particularly in embedded and IoT (Internet of Things) devices that commonly use the MIPS architecture. While exploit development techniques for x86 are well-documented in academic literature, little systematic work exists on how those techniques translate to other architectures such as MIPS. This research addresses that gap by evaluating thirteen stack-based exploit development techniques and subtechniques, originally designed in the context of the x86 architecture, for their applicability to MIPS architectures. For each technique, vulnerable C code was written and compiled into both x86 and a set of …