Digital Commons Network^™

Advanced Motor Control Using Td3 Model-Free Reinforcement Learning, Muhammad Azam

Theses and Dissertations

Motor control plays a critical role in industrial automation, ensuring the precise regulation of speed, torque, and position across various applications. Traditional motor control techniques, such as open-loop, closed-loop, and feedback control, have been widely used but face limitations in handling complex and dynamic systems. Recent advancements in machine learning (ML) offer potential improvements in motor control by enabling systems to learn optimal control policies autonomously. This research investigates the integration of Reinforcement Learning (RL) with Field-Oriented Control (FOC) for the control of Permanent Magnet Synchronous Motors (PMSMs). The study aims to address a significant gap in reward function design, …

An Explainable Ai Framework For Detecting Harmful Algal Blooms (Habs) In Freshwater Lakes, Meera Gopinath Sujatha

Theses and Dissertations

The increase in economic impacts due to the rapid growth of harmful algal blooms (HABs) in freshwater lakes has prompted the development of monitoring and prediction systems. However, limited target data hinders reliable predictions on HAB formations. To address this limitation, this dissertation focuses on providing solutions through data-driven,interpretable, and explainable machine learning models. In Chapter 3, an interpretable multivariate regression model such as Vector Autoregressive (VAR) was used to analyze the important factors that contribute to the formation of cyanobacteria in lakes. The causality tests performed on multiple water quality data helped to determine Alkalinity, Chlorophyll-a (Chl-a), andWater Temperature …

The Wicked Problem Of Moral Distress: Exploring The Experiences Of Rural Clinic Nurses, Sydney Rae Johnson

Theses and Dissertations

Background: Moral distress is an occupational hazard for nurses that can negatively impact nurses, patients, and the healthcare system. Moral distress has been well documented in high-risk care environments. Each nursing care environment has its own unique triggers for moral distress, but these triggers are unknown in rural clinic nurses. Design and Purpose: This convergent mixed methods study sought to gain a broader understanding of moral distress in nurses working in rural clinic settings.

Methods: Convergent mixed methodology was used to gain a broader understanding of moral distress in nurses working in rural clinic settings. Following ethical approvals, informed by …

The Role Of Student Loan Debt On Delayed Homeownership Among Black American College Graduates, Dedan Makongoro Kusaga

Theses and Dissertations

The growing burden of student loan debt in the United States has raised significant concerns about its broader social and economic impacts, particularly on young adults’ ability to achieve financial milestones such as homeownership. Black American college graduates are especially affected, often carrying higher loan balances and facing greater financial barriers due to historical and structural inequalities. This quantitative study examined the role of student loan debt and other factors influencing delayed homeownership among Black American college graduates, using the public-use Baccalaureate and Beyond (B&B: 2008/2018) dataset from the National Center for Education Statistics (NCES). Findings indicated student loan debt, …

Geothermal Sweep Efficiency Enhancement Potential Analysis Using Geological Modeling And Numerical Simulation On Unconventional Deadwood Formation, Ashraf Mohammed

Theses and Dissertations

This study investigates the potential to enhance geothermal sweep efficiency in the fractured, low-permeability Deadwood Formation using a cellulose-based biopolymer and gel treatment. A geological model was developed using well log and structural data from four wells in the Williston Basin and subsequently upscaled into a numerical reservoir simulation in CMG/STARS. Laboratory core-flooding experiments on Deadwood samples were used to calibrate gel behavior under high-temperature (160 °C) and high-salinity (17% TDS) reservoir conditions.Simulation results indicate that a short-duration gel treatment—equivalent to 0.03 pore volumes over one year—can significantly reduce channeling through high-conductivity fractures. The reduction in channeling improves thermal conformance …

Social Support And Gratitude In Adolescents: An Exploratory Study, Mimi Webb Kurtz

Theses and Dissertations

Dispositional gratitude is a construct associated with numerous benefits in youth. However, existing research has primarily focused on the outcomes of gratitude, with limited exploration of the underlying factors that may contribute to individual differences in its development. Because gratitude is considered malleable, identifying key factors associated with its growth in youth is essential. The present study aims to address this gap by exploring perceived social support as a presumed antecedent of dispositional gratitude in older adolescents. Cross-sectional, self-report data and structural equation modeling were used to assess the relationship of perceived social support with gratitude levels among high school …

Influence, Confidence, And Interest In Mathematics: The Route To Increasing Female Participation In Stem, Lisa Galbreath Neaton Black

Theses and Dissertations

Women are underrepresented in STEM professions despite initiatives to encourage young women to pursue these financially rewarding careers. Studies show this divide is not due to inability or lack of female participation in higher education, as women tend to outscore their male counterparts on standardized tests and make up approximately 59% of the postsecondary student population. Rather, the disconnect in the high school-to-college STEM pipeline for young women seems to center on mathematics. In response, this action research study focused on addressing societal influence and mathematical confidence and interest using a constructivist approach in an honors Algebra 2 class.Hands-on activities, …

Digital Twins For Flexible Manufacturing, Drew Brandon Sander

Theses and Dissertations

With the establishment of Digital Twins as an enabling technology for Industry 4.0, it is time to transition from the previous foundations to works that implement and highlight the capabilities Digital Twins present. The Industry 4.0 paradigm has recentered the focus on customizability, leading to reemerging goals of flexibility within manufacturing. Empowered through new cyber-physical systems, new enabling technologies are driving the revolution. To identify how Digital Twins as an enabling technology contribute to flexibility within manufacturing, a comprehensive investigation is conducted along with a detailed case study. A systematic literature review is conducted to analyze quality Digital Twin implementations …

The Relationship Between Cardiac Patient Beliefs And Experiences With Insurability And Their Decisions On Whether Or Not To Pursue Genetic Testing, Julia Schoeni

Theses and Dissertations

Since the enactment of the Genetic Information Non-Discrimination Act (GINA) in 2008, genetics providers have been incorporating conversations about GINA in pre-test counseling. There is currently limited evidence of the effects of personal or family histories of cardiomyopathy or aortopathy and associated genetic testing on patients seeking insurance policies not protected by GINA, including life, long term care, and disability insurance. This study aimed to determine whether individuals with a personal or family history of cardiomyopathy or aortopathy are having conversations about future insurability with their healthcare providers and how they perceive their ability to get these insurances when deciding …

Knowledge And Ontology Enhanced Approach To Natural Language Understanding (Koe-Nlu) In Computational Social Media And Healthcare, Naga Usha Gayathri Lokala

Theses and Dissertations

Natural Language Understanding (NLU) faces both opportunities and challenges as the amount of social media and healthcare data grows. This is particularly evident in context-sensitive applications such as evaluating cognitive health, identifying mental health symptoms, and monitoring drug abuse. Even though traditional NLU models work well for processing language in a wide range of areas, they often lack the ability to understand language in a specific domain, reason in context, and incorporate structured external knowledge. This dissertation talks about the Knowledge and Ontology Enhanced Approach to Natural Language Understanding (KOE-NLU), a new framework that is meant to make NLU systems …

“Digital Shame Shift”: From Telling The Pain To Recording The Truth — Black Maternal Health And Digital Counter-Narrative Storytelling On Tiktok, Odera Covenant Ezenna

Theses and Dissertations

This dissertation explores how digital storytelling on TikTok is used to challenge medical racism, with a particular focus on Black maternal health. Guided by Critical Race Theory (CRT) and Critical Technocultural Discourse Analysis (CTDA), the study examines how TikTok users—ranging from Black mothers to healthcare professionals—create and circulate counter-narratives through two prominent campaigns: #BlackMaternalHealthWeek and #BlackMamasMatter. These digital stories serve as acts of resistance, disrupting dominant medical discourse and amplifying the lived experiences of Black birthing individuals. The research analyzes over 2900 TikTok videos posted between 2021 and 2024, identifying key themes, storytelling strategies, and rhetorical shifts over time. The …

Involvement Of Integrated Stress Response In Primary And Secondary Dystonia, Tricia Aleena Dulice Simon

Theses and Dissertations

ABSTRACT Dystonia is the third most common movement disorder in the United States of America , the first two being essential tremor and Parkinson’s disease. Gaining mechanistic knowledge about pathobiology of dystonia is essential for development of effective therapies. As the only therapies currently available are invasive procedures such as deep brain stimulation (DBS) or frequent botulinum toxin injections, it is critical to understand the underlying molecular mechanisms leading to dystonia. A maladaptive integrated stress response (ISR) involving dysregulation of the eukaryotic translation initiation factor  (eIF2) mediated signaling is observed in DYT-PRKRA patient cells. Mutations in PRKRA gene, which …

Examining Mental Health Providers’ Differential Sensitivity To Youth And Caregiver Treatment Engagement Problems By Studying Clinical Decision-Making Behaviors, Wendy Chu

Theses and Dissertations

Clinical decision-making is a systematic process of collecting and using information to guide action regarding client care. Across frameworks of clinical decision-making, there is an emphasis on the assessment of a problem – which involves considering, identifying, and selecting a problem – as it directly informs intervention. In youth mental health services, problems related to treatment engagement or the ability to meaningfully participate in services are important to assess given their association with premature termination and poor outcomes. However, research suggests that assessment of engagement problems may be challenging, and one potential reason pertains to providers’ ability to assess across …

Self-Regulation In Children With Fragile X Syndrome: Biobehavioral Underpinnings, Familial Predictors, And Outcomes, Erin Evelyn Hunt

Theses and Dissertations

Self-regulation is a multifaceted construct that occurs on biological, cognitive, emotional, and behavioral levels. Self-regulatory abilities typically emerge in the first years of life and continuously develop through early adulthood. There is considerable interindividual variability in developmental trajectories of self-regulation which are associated with numerous adaptive and maladaptive outcomes. Factors influencing the development of self-regulation include interacting genetic and social environmental factors. Given the high heritability of self-regulation, within-family associations are common.

Individuals with Fragile X syndrome (FXS), an inherited, single-gene neurodevelopmental disorder, have heightened vulnerability for self-regulation deficits that are evident in early infancy; however, the developmental trajectories and …

Cerebellar Contributions To Speech And Clinical Outcomes In Stroke: A Multimodal Investigation Of Structural Integrity Across Chronic And Acute Cohorts, Makayla Joy Gibson

Theses and Dissertations

This dissertation investigates the critical role of the cerebellum in speech production, with a focus on chronic post-stroke apraxia of speech (AOS), lesion-related cerebellar degeneration, and age-related changes in cerebellar structure among healthy individuals. While speech deficits have traditionally been attributed to cortical lesions, mounting evidence suggests that the cerebellum contributes significantly to speech-motor planning, execution, and error correction. Using multimodal neuroimaging, lesion-symptom mapping, and standardized speech assessments, this research examines cerebellar gray matter volume (GMV) across three complementary studies.

Aim 1 evaluates the association between cerebellar GMV and AOS severity in individuals with chronic left hemisphere stroke. Findings support …

Origen Of Alexandria On Cancticles: Exegeses And Homilies As Forming Christian Identity, Annaline Bethany Cely

Theses and Dissertations

This dissertation focuses on how Origen of Alexandria, through both homilies and exegetical commentary practice, presents Canticles as a piece of literature fittingly understood as Scripture. For Origen, Scripture is the source text by which Christians can engage with God and mold their lives upon Christ. This dissertation mimics Origen's own methodology by performing a line-by-line reading of his work, which allows the reader immediate access to Origen's work while also acting as a commentary of Origen's commentary. As of Fall 2025, there are no commentaries in English on any Church Father (only translations) which is concerning as the reading …

Modification Of Nanoparticles For Designed Interfaces, Tony Lee Neely, Jr.

Theses and Dissertations

The work contained herein, is focused on the design, synthesis, and characterization of polymer nanocomposite interfaces and the property enhancement afforded from said interface design. Through the use of reversible addition fragmentation chain transfer (RAFT) polymerization for the grafting of polymer chains to silica nanoparticles, the surface of silica nanoparticles can be manipulated to tune the properties of the nanocomposite as a whole.

In the first part of this work, heterogeneity is introduced onto the surface of silica nanoparticles via a sequential RAFT polymerization to afford a bimodal brush system. A densely grafted, short brush population is polymerized from the …

Persistence Of Southwestern White Pine (Pinus Strobiformis) In An Ever-Changing Environment, Shruti Shrivastava

Theses and Dissertations

Abstract

Local adaptation is known to occur in multiple tree species, with climate as a main force for it occurring, indicating adaptation and changes occurring in spatially and temporally changing climates. With increased climate change, the question now is what future persistence may appear as, and by what magnitude trait mismatch may occur. This is observed in southwestern white pine (Pinus strobiformis) for drought-response traits: resistance (RT), recovery (RC), and resilience (RS). Using previously collected data, the genetic and phenotypic diversity were analyzed. Using that information, the trait values for individuals where only genetic data was known was …

Characterization Of Nanoplastic-Induced Exacerbation Of Asthmatic Pathophysiology In A Murine In Vivo Model, Keith Li

Theses and Dissertations

As global plastic production increases, so does the environmental and biological presence of nanoplastics (NPs), raising growing concerns about their potential impact on human health. These particles have been detected in various organs, including the lungs, yet their role in respiratory inflammation remains largely unexplored. Emerging evidence suggests that NP exposure may influence immune responses in the lungs, particularly in individuals with preexisting conditions such as asthma. However, the specific ways in which these particles interact with allergen driven inflammation are still unclear.

In this study, a murine model of allergic airway inflammation was used to investigate how surface modified …

Intervertebral Lateral Bending Moment Differences In The Lumbar Spine Of Baseball Pitchers Across Throwing Velocities, Justin Humenay

Theses and Dissertations

Introduction Baseball pitching imposes substantial mechanical demands on the lumbar spine, a crucial link in the kinetic chain responsible for transferring energy from the lower body to the upper extremity. While increased pitch velocity is associated with greater trunk forces the specific intervertebral loading patterns during high-velocity pitching remain unclear. This study investigates differences in lateral bending moments across lumbar spinal segments between collegiate pitchers throwing at high versus low velocities.

Methods Twenty right-handed collegiate pitchers were divided into two groups: high-velocity (n = 10, 90.3 ± 1.6 mph) and low-velocity (n = 10, 81.6 ± 1.1 mph). Motion capture …

Automated Treatment Planning Framework For Cervical Cancer In Brachytherapy, Suman Gautam

Theses and Dissertations

Brachytherapy (BT) is a critical treatment modality for cervical cancer that delivers ionizing radiation directly to the tumor using intracavitary (IC) and/or interstitial (IS) applicators. In high dose-rate (HDR) BT, a remote afterloader guides the radioactive source to specific dwell positions for defined durations, known as dwell times, allowing for a conformal dose to the tumor while minimizing exposure to surrounding organs at risk (OAR). However, due to the inherent nature of ionizing radiation, some dose to OARs is unavoidable, creating a fundamentally conflicting objective in treatment planning: maximizing tumor coverage while minimizing OAR dose. This characterizes the problem as …

Bugs In The Flux: Links Between Arthropod Diversity And Spatial Variation Of Soil Respiration In A Temperate Forest, Erin-Darby H. Mcclain

Theses and Dissertations

Soil respiration (Rs) is the largest terrestrial flux of carbon (C) to the atmosphere, with heterotrophic contributions to Rs varying spatially and temporally. While microbes are the primary and most thoroughly studied source of soil heterotrophic respiration (Rh), contributions from higher trophic organisms, including arthropods, are rarely quantified and poorly understood. Arthropod abundance and diversity correspond with variation in soil microclimate, which is influenced by site factors including canopy structure, site productivity, and disturbance. However, the extent to which these site factors influence arthropod abundance and diversity, and consequently, spatial variation in Rs is not known. The objective of our …

Advanced Air Preheater Sealing Systems For Enhanced Efficiency And Reliability In Thermal Power Plants, Pavan Kumar Ravulaparthy

Theses and Dissertations

Global electricity generation still relies heavily on thermal power plants, which consume vast amounts of fuel and emit significant amounts of carbon dioxide. A major but often overlooked source of inefficiency in these plants lies within the rotary regenerative air preheater (RAPH), a critical heat-exchange component where air leakage can exceed 20% in aging units. This leakage increases fuel consumption, parasitic fan power, and CO₂ emissions, while degrading boiler reliability.

This research introduces advanced adaptive sealing systems designed to mitigate these losses by dynamically compensating for rotor eccentricity, thermal distortion, and wear under harsh operating conditions. Brush seals, composed of …

Scopolamine-Induced Modulation Of Serotonin And Dopamine Transporters Activity: Behavioral And Molecular Insights Into Rapid Antidepressant Action, Deepak Karunakaran

Theses and Dissertations

Major depressive disorder (MDD) affects over 350 million individuals worldwide and is characterized by profound dysregulation of serotonin (5-HT) and dopamine (DA) systems that govern mood, reward processing, and motivation. The serotonin transporter (SERT) and dopamine transporter (DAT), both dynamically regulated through phosphorylation, serve as critical determinants of synaptic monoamine signaling. Despite decades of therapeutic development, current antidepressants require 4-6 weeks to achieve efficacy, and approximately one-third to half of patients develop treatment-resistant depression. The emergence of rapid-acting antidepressants like ketamine represents a paradigmatic shift, demonstrating symptom relief within hours; however, ketamine's therapeutic potential remains constrained by abuse liability, dissociative …

We Are Worthy Of Investment: Exploring Forms Of Cultural Capital Among Black American Families, Joyice Robinson Myers

Theses and Dissertations

This three-paper dissertation investigates how the cultural wealth of Black American families functions as a foundation for educational, developmental, and economic outcomes, especially for Black males, across childhood, adolescence, and the transition into adulthood. Grounded in frameworks of the Revised Cultural Wealth Model, African American Male Theory, and the Racial Stratification Model, the research repositions Black families as producers of capital rather than subjects of deficit. In Paper Paper 1, I synthesized scholarship on family structure, educational attainment, and economic standing, framing racial "achievement gaps” as long-standing education debts owed to Black males. In Paper 2, I used longitudinal data …

Knowing By Heart: Philosophical Dimensions Of Humanistic Mathematics Education, Catherine Henney

Theses and Dissertations

This project seeks to revive interest in late twentieth century humanistic mathematics education (HME) so that its principles might cross the boundary of higher education and settle in corners of the K-12 math education space. In particular, HME’s theme of teaching math humanistically directs attention to features and phenomena that bear strongly on students’ daily classroom experiences. Personhood, agency, inquiry, meaning, environment, feelings, relationships: these elements invite a more thorough meditation and philosophical analysis. Though it is a largely philosophical endeavor, this project is enlivened by classroom vignettes and case studies that bring practical relevance to HME’s core principles. Chapters …

Therapy-Induced Senescence In Cancer: Developing Senolytic-Based Combination Strategies To Delay Re-Emergence Of Triple-Negative Breast Cancer, Eesha Chakraborty

Theses and Dissertations

Therapy-induce senescence (TIS) represents a major biological outcome of many anticancer treatments and is increasingly recognized as a strategic vulnerability in triple negative breast cancer, which is a highly aggressive subtype with limited therapeutic options and frequent relapse. Here, we probed TIS as a primary cellular response that may ultimately compromise long-term outcomes using standard chemotherapeutic agents in TNBC as well as the antibody-drug conjugate sacituzumab govitecan (SG). Both chemotherapy and SG reliably induced pronounced senescence across TNBC models, yielding durable growth arrest, however, also generating a persistent reservoir of viable tumor cells capable of eventual proliferative recovery, a hallmark …

Unraveling The Reactivity Of Nitrate Ester Explosives: Insights From Femtosecond Time-Resolved Mass Spectrometry And Computational Chemistry, Erica Britt

Theses and Dissertations

This dissertation uncovers the ultrafast molecular mechanisms underlying the decomposition of nitrate ester explosives—nitroglycerin (NG), ethylene glycol dinitrate (EGDN), and amyl nitrate—through the integration of femtosecond time-resolved mass spectrometry and advanced computational chemistry. Although these compounds play fundamental roles in both military and civilian contexts, the precise molecular dynamics governing their pronounced reactivity and impact sensitivity have remained inadequately characterized. Our research establishes that low O–NO2 bond dissociation energies are the primary driver of ultrafast fragmentation and high reactivity in all three esters. The distinctive molecular architectures of these esters dictate their explosive properties: NG’s tri-nitrate configuration leads to exceptional …

Predictive Inference For Ion Concentration With Machine Learning And Bayesian Methods, Alexandra B. Ulbing

Theses and Dissertations

Ultraviolet--visible (UV--Vis) spectroscopy produces high-dimensional signals that are strongly collinear, shift with concentration, and exhibit heteroskedastic, non-Gaussian noise. These features make supervised regression from spectra to ionic concentrations statistically challenging and limit the reliability of methods that assume linear structure or homoscedastic errors.

This dissertation develops two complementary frameworks for prediction and uncertainty quantification in UV--Vis spectroscopic regression: (1) frequentist stacked ensembles combined with distribution-free conformal prediction, and (2) Bayesian hierarchical modeling and Bayesian stacking. Together, they provide a unified view of model-based and distribution-free uncertainty across nickel and nickel--cobalt datasets.

The frequentist component builds ensembles of Functional Data Analysis …

Exploring The Role Of Host Immune Responses And Bacterial Sensory Pathways In The Development Of Treponema Denticola-Mediated Periodontal Disease, Annie N. Hinson

Theses and Dissertations

Periodontitis is a chronic inflammatory disease driven by dysbiotic microbial communities and maladaptive host responses. Treponema denticola, a spirochete pathobiont, is strongly associated with disease severity. However, the molecular mechanisms underlying its interaction with host tissues and regulation of virulence remain incompletely understood. This work examines both the epithelial immune responses and bacterial transduction systems that shape T. denticola pathogenesis. Transcriptomic analysis of gingival keratinocytes revealed IL-36γ as the most highly induced cytokine following infection with T. denticola. Functional studies demonstrated that IL-36γ induction occurs in a dose- and time-dependent manner through TLR2/6 signaling, requiring the NF-κB, PI3K/Akt, and …