Digital Commons Network^™

Data Driven Monitoring And Control Of Laser Powder Bed Fusion Process, Jose De Jesus Galarza

Theses and Dissertations

The Laser Powder Bed Fusion Process (LPBF) has been one of the main processes of additive manufacturing, enabling the manufacturing of complex geometries, customization, and lightweight parts. Modern LPBF processes have integrated monitoring systems that capture the light emissions per layer for quality assurance. However, standard defect detection algorithms have not yet achieved the high precision required due to the inherently variable nature of the signal, insufficient data for model training, and the confounding effects of the print.

The processes still have some challenges, such as characterizing the roughness from the build parameters alone, improving the pore detection using the …

Typing Proficiency And Its Relationship To Outcomes In Online Writing Assessments, Agustin J. Cantu

Theses and Dissertations

As writing assessment increasingly occurs in digital environments, students must demonstrate not only composition skills but also sufficient transcription fluency to produce responses under timed conditions. This quantitative study examined the relationship among structured typing practice, transcription fluency, and writing performance among students in Grades 3 and 4 at IDEA Public Schools. Specifically, the study investigated whether engagement with Typing.com was associated with improvements in words per minute (WPM) and accuracy, and whether transcription fluency was associated with performance on Internal Assessment (IA) Writing Percent Correct.

Archival district data were analyzed using descriptive statistics, correlational analyses, hierarchical regression, moderation analyses, …

My Journey As A Migrant Bilingual Learner From Student To Teacher: Lessons Learned, Sylvia Lopez

Theses and Dissertations

These reflections in this thesis are an analysis of narratives based on my lived experiences as an immigrant, migrant student who is now a certified Bilingual & Special Education teacher servicing students, many of whom are bilingual, in public school classrooms. My goal is to connect my life experiences to teaching practices and thus embrace and celebrate my linguistic identity. Bilingual educators have a language learning journey that drives their classroom practices. When bilingual teachers reflect on their bilingual trajectory and connect their life experiences to research, they may provide spaces for stronger positive impacts on bilingual students, and their …

What Happens When Leaders Don’T Live Up To The Ideal? How The Leadership Perception Gap Can Undermine Leader Development And Intentions, Julia Macgregor-Peralta

Theses and Dissertations

Despite decades of research on leadership development, we know surprisingly little about why capable, confident people choose not to pursue leadership. This study introduces the Leadership Perception Gap (LPG), a construct that captures discrepancies between ideal leader views and the leaders people actually observe, and tests whether those discrepancies reduce the desirability of leadership roles. LPG was assessed using latent congruence modeling (LCM) to compare ideal leader ratings with vignette-based leader evaluations. The vignettes manipulated leadership style (agentic, communal, balanced) and team composition (all-male, all-female, balanced). Participants were randomly assigned to one condition and evaluated their interest in joining the …

Phenotypic Contribution And Regulation Of Vibrio Parahaemolyticus Cold-Shock Protein Homologue Vp1889, Oleg Borisovich Ermolinsky

Theses and Dissertations

Vibrio parahaemolyticus is the primary causative agent of a form of gastroenteritis called vibriosis commonly acquired from ingestion of raw and undercooked seafood. The primary mitigation of seafood-borne illnesses is immediate storage on ice following catch, which inhibits bacterial metabolism and replication. Mesophilic bacteria such as V. parahaemolyticus induce expression of cold-shock proteins in a process named the cold shock response, which facilitates survival at low temperatures. V. parahaemolyticus bears 3 homologues of the major Escherichia coli cold-shock protein CspA, an RNA chaperone. Induction of E. coli CspA at low temperatures depends on autogenous modulation by its mRNA structure, which …

From Homeland To The Foreign Classroom: The Salaysay Of Filipina Immigrant Teachers In Texas, Shanna Cui Miranda

Theses and Dissertations

Filipina immigrant teachers are a growing presence in Texas schools, especially as districts respond to teacher shortages by recruiting internationally trained educators. This narrative study explores the salaysay of Filipina immigrant teachers in Texas and examines how their funds of knowledge inform their teaching practice. Guided by the research question, What are the salaysay of Filipina immigrant teachers in Texas, and how do their funds of knowledge inform their teaching? The study uses Funds of Knowledge (Moll et al., 1992) as the central framework and resizes it to focus on teachers as holders of culturally developed knowledge. The resized framework …

Assessing Water Quality And Nitrogen Dynamics In Bahia Grande, Texas Using Field And Remote Sensing Data, Sk Taufiqul Islam

Theses and Dissertations

An 8,220-acre estuary in South Texas, Bahia Grande has recently been restored from a disconnected hypersaline basin to a tidal estuary. A spatially explicit water quality index (WQI) was developed and in situ physicochemical data coupled with remote sensing data from Sentinel-2 were used to determine ecological integrity. A WQI from 29.45-53.20 yielded a spatial distribution of water quality that displayed a non-linear spatial trend throughout the estuary. Water quality close to the Brownsville Ship Channel inlet yielded values of 'Moderate/Stressed' water quality (> 50). These areas represent local zones of disturbance where ammonium concentrations were more than 11 µmol/L. …

Bayesian Change-Point Detection In Stock And Cryptocurrency Markets Using Shrinkage Priors, Yosalin Sanchez

Theses and Dissertations

Financial markets often undergo abrupt structural changes driven by political, economic, and geopolitical events, leading to substantial volatility. Detecting such change-points is crucial for identifying structural breaks, improving risk management, and enhancing forecasting performance in financial time series. This study proposes a Bayesian change-point detection framework that incorporates both the t-shrinkage prior and the Horseshoe shrinkage prior. These priors enforce strong regularization on successive differences in mean parameters, enabling the identification of piecewise constant structures in time series data. Posterior inference is conducted using Markov Chain Monte Carlo (MCMC) methods, specifically a Gibbs sampling algorithm, which iteratively samples from the …

Essays On Ai-Driven Analytics For Enhanced Healthcare Delivery: From Onset To Outcomes In Neurological Diseases Management, Gabriel Owusu

Theses and Dissertations

Chronic neurological diseases, particularly Alzheimer's disease and related dementias (ADRDs), pose mounting global healthcare burdens. Despite advances in AI and health information technologies, early detection, precise diagnosis, and effective caregiver support remain elusive. This dissertation proposes innovative AI-enabled analytical frameworks to address these challenges across the full ADRD continuum.

The first essay designs an explainable AI-enabled clinical decision support system (CDSS) using a graph neural network for early AD identification, evaluated through usability studies demonstrating improved risk awareness and clinical engagement. The second essay introduces MADT-RNN, a multi-level attention-based deep transfer recurrent neural network that fuses convolutional and recurrent architectures …

The Effects Of Ai Adoption On Digital Entrepreneurial Intention: A Meta-Analysis, Xandra Precious Okori

Theses and Dissertations

AI adoption and its widespread use have sparked debates about the future of work, job displacement, and the evolving entrepreneurial landscape. While AI is often seen as a threat to traditional employment, research shows that this emerging technology is more likely to change task structures rather than eliminate entire occupations or industries. This shows that there are new entrepreneurial opportunities, particularly digital, that potential entrepreneurs can venture into. This thesis uses a meta-analytic approach to study the relationship between AI adoption and digital entrepreneurial intention, addressing inconsistencies in current research.

Following PRISMA guidelines, a comprehensive search was conducted across Web …

The Effect Of Drought On Avian Migratory Patterns And Stopover Through Texas And Louisiana, Ian Becker

Theses and Dissertations

Extreme weather events pose a massive threat for native ecosystems. As precipitation and temperature patterns are altered due to climate change, drought may become an incredibly severe event on the landscape. Drought directly impacts resources that migratory birds need during stopover en route to breeding and non-breeding grounds. Here, I quantify the impacts of drought on migration through Texas and Louisiana using 26 years of weather surveillance radar data. To understand how drought interacts with the local environment to impact migration, I tested 4 hypotheses displaying drought’s ability to impact migrants in conjunction with climatic and habitat level characteristics. Fall …

From Witness To Weapon: How Elizabeth Barrett Browning’S “The Cry Of The Children” Embodies And Transforms The Rhetorical Situation, Elyssa Vianey Solis

Theses and Dissertations

Elizabeth Barrett Browning’s “The Cry of the Children” employs trauma-driven rhetoric to expose Victorian child labor exploitation.

Combining literary analysis with rhetorical theory, this research contextualizes the poem within 19th-century industrial exploitation, showing how Browning transforms documentary evidence like the 1842 Children’s Employment Commission Report into emotional testimony. Visceral imagery, ironic juxtaposition, and embodied suffering weaponize pathos to reveal systemic abuse and moral urgency. Applying Lloyd Bitzer’s and Richard Vatz’s theories, we can posit that Browning both responds to and defines the crisis, merging poetic protest with social reform as civic intervention.

By engaging Bitzer and Vatz, this paper argues …

Chronicles Of A Caliche Road: Lessons From The Monte Through A Poetic Currere Of Language, Memory, And Identity, Brenda Ochoa

Theses and Dissertations

This autobiographical study explores how language, memory, and identity are shaped through lived experience in the South Texas brushland known as the monte. Situated within the cultural and linguistic landscape of the Rio Grande Valley, the study examines how land, native plants, and regional wildlife function as an informal curriculum that shapes voice, silence, and ways of knowing beyond formal schooling. Grounded in autobiographical inquiry, the study uses poetic currere as both an analytic process and a mode of representation to illuminate the relationship between language experience, memory, and identity across time. Data sources include personal memories, reflective journals, original …

Developing A Qpcr Method For Evaluating Parasitoid Wasps As A Potential Means Of Control Of The Southern Cattle Fever Tick Rhipicephalus (Boophilus) Microplus In South Texas, Abbey Abalos

Theses and Dissertations

Ixodiphagus spp. wasps are natural enemies of ticks that have been reported to cause mortality in multiple tick species. Parasitoid wasps may represent a potential biocontrol alternative to traditional chemical tick control methods, which are challenged by non-target toxicity and the development of pesticide resistance in species of concern such as Rhipicephalus microplus, a pest of livestock that causes billions of dollars in loss to the livestock industry worldwide. Rhipicephalus sanguineus s.l. is a congeneric species of R. microplus, and parasitism of R. sanguineus by Ixodiphagus sp. in areas of co-occurrence has been observed. It is unknown if R. microplus …

A Visit-Count-Based Complete Foraging Strategy For Robot Swarms, Arturo Yahir Gonzalez

Theses and Dissertations

Swarm robotics systems often rely on a balance between exploration and exploitation to perform tasks like Central Place Foraging. While exploitation methods such as pheromone trails and site fidelity are well-studied, the efficiency of the underlying random search exploration remains a challenge, frequently leading to redundant coverage and wasted time as multiple agents repeatedly search the same fruitless areas. This thesis introduces a memory-enhanced exploration strategy designed to improve the efficiency of random search in a swarm of simple robots.

In our proposed algorithm, each robot, constrained with limited memory, periodically logs its recent locations while exploring. This spatial data …

The Impact Of Nutrition On Insecticide Resistance And Gene Expression In Aedes Aegypti, Esmeralda Guadalupe Rosas

Theses and Dissertations

The development of insecticide resistance in Aedes aegypti, a major vector of dengue and Zika viruses, threatens vector control efforts, particularly in endemic regions such as South Texas. Insecticides remain widely used; however, their overuse has accelerated metabolic resistance mediated by cytochrome P450 enzymes. Environmental factors such as larval nutrition may influence mosquito physiology and resistance-associated gene expression, yet this relationship remains poorly understood. This study examines how larval nutritional conditions affect the expression of cytochrome P450 genes linked to pyrethroid resistance in Aedes aegypti. Larvae were reared under five dietary treatments differing in lipid and protein ratios, and adults …

Parasites Of Meaning: When Interpretation Becomes Infection, Kimberly Medrano

Theses and Dissertations

This thesis examines the impulse to seek moral certainty in morally ambiguous first-person confessional narratives and argues that such certainty is unnecessary. When confronted with narrators whose moral positions remain unclear, readers often project their own moral frameworks onto the text to place the narrator within specific moral binaries. This impulse reveals the reader’s discomfort with ambiguity. This study analyzes the confessional narration, No Longer Human by Osamu Dazai. The thesis will explore how its confessional narrator resists moral clarification. Drawing on Friedrich Nietzsche's critique of moral binaries and J. Hillis Miller’s concept of the “Critic as Host,” this thesis …

Teaching Under Restriction: Pre-Service Teachers’ Experiences With Censorship, Johnny Salinas

Theses and Dissertations

This qualitative study examined the perceptions of pre-service teacher candidates at a predominantly minority university in South Texas about educational censorship in K–12 schools. Grounded in critical theory, the research explored how restrictive policies—including book bans and legislation related to race, gender, and identity—affect candidates’ developing professional identities and career aspirations. Data were collected through an anonymous, open-ended questionnaire and analyzed to identify six interconnected themes: autonomy and fear, book bans, policy and legislation, race and identity, subject-specific impacts, and readiness and confidence. Participants described an increasingly tense educational climate marked by heightened scrutiny and ambiguous policy expectations. They voiced …

Soil Water Content Beneath Agrivoltaic Installations In A Subtropical Semi-Arid Climate, John Justin Rodriguez

Theses and Dissertations

Agrivoltaics (AV) not only beneficially influences agricultural microclimates in the field, AV systems can generate on-site energy to offset operational costs, diversify income sources, and improve overall resilience, while providing environmental co-benefits such as reduced heat stress on plants and improved resource use efficiency. This thesis evaluated agrivoltaic shading effects on SWC and soil temperature using high-resolution in situ measurements collected over one year in an active vineyard, incorporating row type, soil depth, shading, and time of day. With precipitation as the primary water source, shaded soils exhibited up to 24.53% lower SWC relative to sun-exposed soils, likely due to …

Linking North American Demographic Trends To Mexican Non-Breeding Grounds In A Migratory Warbler, Majuwana Gamage Dulanthi Dileka Kariyawasam

Theses and Dissertations

Migration enables species to exploit seasonal resources despite high energetic costs and mortality risks, making it a key focus for conservation under environmental change. I investigated migratory connectivity in Orange-crowned Warblers using stable hydrogen isotopes (δ²H) from feathers collected at nine non-breeding sites across Mexico. Results indicated generally weak connectivity (MC = 0.18), with most sites hosting individuals from six breeding clusters across Canada and the United States. However, one northwestern breeding group showed strong connectivity, suggesting crosswise migration to eastern Mexico. By integrating these findings with long-term Breeding Bird Survey data, I detected contrasting population trends, with Pacific Coast …

Structure–Property Engineering Of Sn-Based Hybrid Perovskites Via Bulky Organic Cation Incorporation: From 3d To 2d Architectures, Kevin Alejandro

Theses and Dissertations

This thesis investigates tin-based hybrid organic/inorganic perovskites (HOIPs) as a lead-free alternative to silicon solar cells. To manipulate optoelectronic and efficiency of the semiconductors, methylammonium was substituted with bulky propylammonium and tetrabutylammonium cations to induce quasi-2D/3D Ruddlesden-Popper phases. X-Ray Diffraction confirmed 2D layered phases in propylammonium hybrids (5-15%), while tetrabutylammonium hybrids faced steric limits, triggering vacancy ordered perovskite phases at 1% concentration. Optical analysis showed a bandgap narrowing from 1.30 eV to 1.26 eV with increased substitution. Although photovoltaic performance generally declined, the 10% propylammonium hybrid achieved the highest fill factor of ~0.79, indicating superior internal charge transport. This work …

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 …

Decomposition And Spectral Characterization Of Unsteady Loads In Pulse-Jet Propulsion Testing, Cesar Benitez

Theses and Dissertations

Pulsed jet propulsion systems produce inherently unsteady forces whose time-resolved characterization is essential for performance assessment, yet the measured load signal conflates aerodynamic forcing with the dynamic response of the measurement balance itself. This thesis develops a load centered framework for the dynamic characterization of a pulsed jet system, treating the measured load fluctuation as the primary physical observable rather than attempting full true-thrust reconstruction. A single-degree-of-freedom balance model identified through ringdown testing provides the structural reference scale, yielding a natural frequency of 8.5 Hz and damping ratio of 18%. Power spectral density, phase-averaging, and synchronous–residual decomposition is applied uniformly …

Bridging Culture And Education To Enhance Cherokee Student Health And Wellness, Lindsey Hammer

Theses and Dissertations

Indigenous populations face ongoing health disparities, often worsened by a lack of culturally relevant and Indigenous-led programs and interventions. This dissertation in practice was inspired by the need for community-driven, culturally grounded approaches that address these disparities for Cherokee Nation in Northeastern Oklahoma. Each of the three products are inspired by and aligned with the principles of Community-Based Participatory Research (CBPR), the Cherokee value of gadugi, and the concept of relationality, offering a holistic approach to community health and well-being. Not every product represents a fully implemented CBPR process but rather a CBPR-informed approach. Future stages will emphasize more meaningful …

A Privacy-Preserving, Ai-Driven Framework For Bathroom Activity Monitoring And Health Recommendation In Elderly Care, Collins Poku Obeng

Theses and Dissertations

The rapid aging of the global population necessitates scalable, non-invasive solutions, for monitoring Activities of Daily Living (ADLs) to detect early signs of health decline. This thesis presents a novel, end-to-end framework for monitoring bathroom activities—specifically bathing, toileting, and oral hygiene—using wearable sensors, machine learning and Agentic Artificial Intelligence (AI). The research addresses three critical gaps: the lack of granular activity recognition in privacy-sensitive spaces, the need for personalized health insights without manual logging, and the cybersecurity risks inherent in deploying AI in healthcare. First, algorithms utilizing wearable humidity and accelerometer sensor data were developed to classify hygiene behaviors with …

Reactive-Fluid-Transport Controls On Co2-Eor Applications In The Upper Red River Carbonate Reservoir, Abdelmalek Abes

Theses and Dissertations

Reactive-transport phenomena during CO2 injection in carbonate reservoir were examined in detail. Three core samples from the primary producing units of North Dakota’s Upper Red River Formation (U2-H055, U4-H069, and U6-H009) were used to experimentally investigate geochemical reactions and petrophysical alterations, impacting carbon dioxide enhanced-oil-recovery (CO2-EOR) and geologic-carbon-storage (GCS) projects. During corefloods using a CO2/brine mixture, two samples demonstrated early permeability increases followed by declines, whereas the third sample demonstrated an early decrease; all samples gradually recovered at a later stage. Nuclear magnetic resonance (NMR) measurements revealed slight porosity increases due to dissolution-induced wormholes, while the pore-size distribution (PSD) shifted …

Studying The Hidden Heat: A Theoretical Approach To Better Understanding The Thermal Conditions Of The Yellowstone Volcano In Wyoming, Usa, Daniel Burke Brunson

Theses and Dissertations

Using the spatiotemporal record of the 2.1–0 Ma ignimbrite flare-up of the Yellowstone Plateau Volcanic Field (YPVF) as a proxy for batholith formation at depth, this dissertation develops and applies the Finite Difference Heat Flow Simulation (FDHFS) program to model crustal thermal evolution beneath the supervolcano. FDHFS, a modular C++ numerical simulator, solves the transient heat equation incorporating variable thermal conductivity, radiogenic heat production, and directional advection in three-dimensional Cartesian grids. Validation against analytical benchmarks and seafloor-spreading analogs confirms its fidelity for combined conduction-advection processes in heterogeneous crustal settings.

High-resolution volume–time analysis of major ignimbrite pulses (Huckleberry Ridge, Mesa Falls, …

Critical Minerals Recovery From Oil And Gas Fields Produced Water In The Bakken Formation, North Dakota, Md Jakaria

Theses and Dissertations

The growing demand for critical minerals essential to clean energy technologies presents an opportunity to transform oilfield produced water (PW) – traditionally treated as waste – into a valuable resource. This dissertation investigates the recovery potential of lithium, salts, and other critical elements from produced water in the Bakken Formation, North Dakota, and evaluates the economic feasibility of integrating such recovery processes into existing petroleum operations. Comprehensive geochemical analyses were conducted on samples collected throughout the Bakken, revealing total dissolved solids (TDS) ranging from 46,815 to 327,714 ppm and lithium concentrations exceeding 200 ppm in several wells, indicating economically recoverable …

Filling The Gaps: Rural-Remote High School Teachers’ Perceptions Of Professional Training In Student Mental Health Preparedness, Angela N. Muhs

Theses and Dissertations

Rural-remote high school teachers are frequently the first to notice and respond to student mental health concerns, yet they operate within communities characterized by significant shortages in mental health providers. Access to professional mental health services in these settings remains persistently limited, placing considerable responsibility on teachers who may lack adequate preparation. This study employed an interpretive case study design to qualitatively examine how rural-remote high school teachers in North Dakota perceive their professional training and overall preparedness in addressing student mental health concerns. Twelve licensed teachers, whose experience ranged from six months to 33 years, participated in in-depth interviews. …

Aircraft Fault Detection Via Weight And Bias Analysis Of A Custom First Neural Network Layer, George Harrison Chen

Theses and Dissertations

Fault detection in aircraft is traditionally handled through redundant hardware and comparison algorithms to detect failures. Alternatives like model-based residual generation and data-driven approaches such as supervised fault classification and unsupervised anomaly detection have been explored, but they suffer from practical limitations; model-based methods require accurate system models, and data-driven methods have large constraints on the data limiting scalability and adaptability. This work presents a purely data-driven neural network architecture featuring a custom first layer designed for real-time fault detection where the weights and biases of this layer are used to detect faults. The network requires zero supervision and complements …