Digital Commons Network^™

Balancergnn: Balancer Graph Neural Network For Imbalanced Datasets, Mallika Boyapati

Dissertations

Addressing imbalanced datasets is challenging due to machine learning models' inclination to learn the majority class. Graph construction plays a major role in determining how Graph Neural Networks (GNNs) perform on imbalanced datasets. In this research, we introduce the BalancerGNN framework to tackle highly imbalanced datasets, demonstrating its effectiveness in fraud detection as one of the case studies. This framework is designed to work for any binary node classification dataset with significant class imbalances. This research addresses the following questions: i) How effective are feature engineering techniques in the case of imbalanced datasets? ii) How do graph representation learning and …

Warriors And Guardians: Police Recruit Role Orientation And Heterogeneity, Robert Boxerman

Dissertations

American police have experienced an expansion of duties over the last century, and their function has become increasingly diverse. As a result, researchers have developed role orientation typologies to understand how officers view themselves, their attitudes toward their work, and their responsibilities. One such typology is the warrior/guardian framework, where warrior-oriented officers see themselves as crime-fighting soldiers in conflict with criminals, while guardian-oriented officers view themselves as protectors of the community and providers of broader public services. Despite its popularity, there is limited empirical evidence supporting this framework. Further, little research examines how police recruits differentially view their role as …

Emission Behavior At The Single Emitter Scale From A Porous Media Ionic Liquid Ion Source, Thomas Victor Kerber

Dissertations

Ionic liquid ion sources (ILIS) are being developed as one solution to fill a technology gap in low power, high efficiency, high specific impulse space propulsion systems. With a sufficiently intense electric field applied between an emitter electrode and an extractor electrode, charged particles are extracted from the fluid surface and accelerated out of the thruster. In this work, three experimental campaigns examine emission behavior of a single emitter ILIS made of porous material that allows passive propellant feed via capillary action of the ionic liquid 1-ethyl-3-methylimidazolium tetrafluoroborate (EMI-BF₄).

Repeated measurements of the emitter and extractor current as …

How New Mathematics Teachers Develop Teacher-Student Relational Pedagogy, Dustin Kinser

Dissertations

This study investigated the support structures implemented with new mathematics teachers to help them build relational pedagogy with their students to determine their effectiveness. The literature review examines topical research, gaps in literature and theoretical frameworks to justify the study. The case study investigated new math teachers and their processes of building positive teacher-student relationships using the support structures that they were taught on their way to becoming a teacher. Math teachers were interviewed to find any common themes across the study and find out what is truly working or not working so that the process can be improved. Another …

Data-Driven Decision Making For Quality Control In Foundry Applications, Ronit Shetty

Dissertations

In the transformative landscape of Industry 4.0, advanced quality control in manufacturing demands innovative methods for processing and analyzing datasets. This dissertation presents a comprehensive study on leveraging high volume data and machine learning to enhance decision making in the foundry industry. The research explores three crucial challenges in the foundry industry: predicting surface roughness, monitoring refractory coating thicknesses, and comparing feature extraction techniques for surface quality classification. The findings underscore the transformative potential of integrating advanced feature engineering techniques and machine learning into manufacturing quality control.

The first of the three challenges introduces a framework that integrates digital images …

Utilizing Drainage Induced Pfas Enrichment In Cascade Generated Foam For Efficient Removal At Wastewater Treatment Plants, Ethan Samuel Coffin

Dissertations

Observed trends in municipal solid waste landfills reveal a distinct disparity between per- and polyfluorinated alkyl substances (PFAS) composition entering in waste, mostly as diPAP and FTOH, and leaching out as FTCA and PFCA. These patterns are elucidated by compiling PFAS compositions in paper, textiles, and carpet, with known precursor transformations that generate FTCA and PFCA in leachate. Landfill leachate is commonly discharged to wastewater treatment plants (WWTP), which are ineffective at degrading PFAS and only serve as key conduits and discharge points for PFAS to the environment. Foam fractionation has been identified as a promising technology for concentrating and …

Techniques For Enabling Advanced Adas Features: Operation In Inclement Weather And Use Of Infrastructure Information, Parth Kadav

Dissertations

Modern vehicles have undergone a transformation with the widespread integration of Advanced Driver Assistance Systems (ADAS) technology becoming the new standard and are set to be mandated by the by the National Highway Traffic Safety Administration (NHTSA) for all passenger vehicles and light trucks. ADAS features have proven to prevent or mitigate crashes by either alerting or assisting the driver. ADAS typically utilizes a forward-facing camera, which comes standard in modern vehicles to provide limited automation features such as Lane Keeping Assist (LKA), and Lane Centering Assist (LCA) to improve driver safety. These systems rely on the assumption that vehicle …

Turbulence And Energetic Ion Production In The Partially Magnetized Hollow Cathode Plume, Margaret Mary Mooney

Dissertations

Hall effect thrusters (HETs) are the most widely used electric propulsion (EP) device for in-space satellite propulsion. EP devices provide high efficiencies for extended mission lifetimes and low thrust for precision maneuvers. The hollow cathode is a critical HET component and undergoes extensive lifetime testing in addition to the lifetime testing of the full HET. Significant density gradients, non-Maxwellian electron behavior, and magnetic fields sufficiently strong enough to magnetize electrons in hollow cathode plumes create favorable conditions for the formation of plasma instabilities, which have an impact on cathode lifetime. Cathode qualification testing is typically conducted independently and includes a …

The Ebony Edge: A Qualitative Exploration Of Math Success Among Black College Women, April Ruiz

Dissertations

Historically, women have been underrepresented as leaders in STEM. However, according to the National Science Foundation (2022), women accounted for a little more than half of the college-educated workforce and underrepresented minority women increased in broad science and engineering occupational categories. This promising upturn underscores the importance—if progress is to continue—of better understanding why some African American women succeed in and persist with their study of college mathematics.

This study aimed to explore the experiences of Black college women attending a predominantly White institution in the Midwest, to better understand what reasons Black college women ascribe to their success in …

Quadratic Stochastic Processes: Algebraic Structures And Their Applications, Taimun Saleh Qaisar

Dissertations

This research focuses on the algebraic structures of the Quadratic Stochastic Processes (𝑄𝑆𝑃𝑠). In this work, we first study 𝜉𝑎- Quadratic Stochastic Operators (𝑄𝑆𝑂𝑠) linked to the partition P3. We simultaneously discuss the dynamics of the obtained 𝑄𝑆𝑂𝑠. Moreover, algebraic structure of the associated genetic algebra is studied. Further, we build Quadratic Stochastic Processes (𝑄𝑆𝑃𝑠) using the given Markov processes. Consequently, we obtain an ordinary differential equation for the resultant Quadratic Stochastic Processes (𝑄𝑆𝑃𝑠). Besides, we apply the solution of this ordinary differential equation for the option pricing problem. Thereafter, we construct Quadratic Stochastic Processes (𝑄𝑆𝑃𝑠) in three-dimensional space by …

Measurement Of Groundwater And Contaminant Fluxes In Fractures Using A Combined System Of Passive Flux Meter And Multiport Sampler, Qasim Raza Khan

Dissertations

Groundwater and contaminant movement in fractured rock aquifers is highly variable. Its dependence on fracture apertures and orientation as well as fracture network interconnectivity is not well understood. This poses a challenge to the measurement of groundwater and contaminant fluxes, especially when using open-hole techniques, which significantly alter natural flow conditions by connecting different fractures along an open borehole or a well. Hence, downhole techniques to directly measure groundwater fluxes and map fractures' locations, orientations, and apertures are considered valuable tools. In this work, the use of Fractured Rock Passive Flux Meter (FRPFM) with invisible tracer and visible dye component …

Overcoming Motor Imagery Bci Illiteracy: Adaptive Decoding And Knowledge Transfer In Eeg-Based Brain-Computer Interfaces, Zaid Shuqfa

Dissertations

Brain–computer interfaces (BCIs), also known as brain–machine interfaces (BMIs), enable direct communication between the brain and external devices without the involvement of peripheral nerves or muscles. Among various BCI paradigms, motor imagery (MI)–based BCIs are particularly appealing due to their intuitive, cue-independent nature, allowing users to issue control commands at will. MI–BCIs hold substantial promise for improving the quality of life of individuals with motor impairments, as well as enhancing hands-free control for healthy users. However, their widespread adoption remains limited by challenges such as low signal-to-noise ratio, inter- and intra-subject variability, and the need for frequent calibration. These challenges …

Upper-Level Undergraduate Pre-Healthcare Students’ Journeys To Graduation And Health Professional Graduate Programs, Holly L. Sisson

Dissertations

Despite decades of research on undergraduate student retention and persistence, only a handful of researchers, such as Dumke et al. (2018) and Stull et al. (2021), have looked specifically at pre-health students preparing for graduate health professional programs and the complex challenges these students face while trying to achieve their goals. Very little research focused on upper-level undergraduate students pursuing graduate health professional programs, such as physical therapy, occupational therapy, physician assistant, or similar graduate health professional programs excluding medical school. To help fill this gap, my study focused on the experiences of pre-healthcare students as they navigated their undergraduate …

Development Of Al Ain Flash Flood Risk Maps\ Utilizing High-Resolution And Accurate Remote Sensing Data, Khaled Khamis Al Arfati

Dissertations

Al Ain City has undergone significant land use transformations from 1992 to 2022, marked by a population increase of over 50% and extensive development activities. This period has seen the construction of new residential areas, infrastructure, and commercial establishments, as well as enhancements to green spaces. An analysis of the Digital Terrain Model (DTM) revealed an 83% alteration in the terrain due to urbanization and shifting sand dunes, with most elevation changes under 5 meters.

The primary aim of this dissertation is to develop accurate flash flood risk maps for

Al Ain using high-resolution remote sensing data. This research highlights …

Exploring The Relationships Between G2g, G2e And G2c E-Government Interactions And Organizational Readiness For Citizen Centricity In The Uae Government: Organizational Culture As A Moderator, Esam Al Sayed Ahmed

Dissertations

The UAE has topped the e-Gov development rankings globally over the last two decades. But during the era of the COVID-19 pandemic, certain problems befell the model of e-Gov, like no coherent strategy, inconsistencies in digital practice, inadequate collaboration, the lack of mechanisms for innovation, poor digital talent, and concerns with public trust. After the pandemic, the government released its digital strategy (2021-2025) as part of the rapid recovery plan to stimulate the economy and society. The strategy aimed at increasing sustainability and innovation and putting citizens first. Yet, the strategy can be improved in regard to how prepared government …

Exploring Date Pomace As A Functional Ingredient In Bread: Nutritional And Functional Properties, Alaa Almoumen

Dissertations

This study investigated the incorporation of desugared date fruit pomace into wheat bread rolls and evaluated its effects on dough handling, bread quality, staling behavior, sensory acceptability, and nutritional composition. The research was conducted in three experimental phases: (i) development and characterization of a high-fiber dietary ingredient (HFDI) from date pomace, including its physicochemical and functional properties; (ii) bread fortification and quality assessment, where wheat flour was partially replaced with 0–20% HFDI to evaluate its effects on dough rheology, bread texture, color, moisture retention, shelf life, and consumer acceptance; and (iii) nutritional and physiological evaluation of the fortified breads, including …

From Microplastic Impact To Biodegradation Solutions: Investigating Microplastic Pollution, Microbial Responses, And Efficacy Of Synthetic Microbial Consortia In Plastic Degradation, Rener Sahot De Jesus

Dissertations

Plastics, including microplastics, pose significant environmental threats due to their widespread presence and harmful ecological effects. This dissertation present three distinct, yet interconnected studies. First, a study on microplastic contamination in urban recreational parks was conducted in Al Ain, United Arab Emirates. Results showed that low-density microplastics were present in 87% of soil samples, with spectroscopic analysis identifying synthetic polymers such as polyethylene and polypropylene. Additionally, these microplastics were found to negatively affect soil pH and moisture levels, emphasizing the need for enhanced monitoring and management strategies. Second, the effects of ground microplastics on Photobacterium leiognathi strains, a marine luminous …

An Investigation Into The Effectiveness Of High School Models Of Instruction In English Language Arts For Exceptional Education Standard Diploma Students, Lori A. Rath Minton

Dissertations

This study examined the effectiveness of high school instructional models in English Language Arts (ELA) for Exceptional Student Education (ESE) students pursuing a standard diploma. The purpose was to compare self-contained and inclusion models within the framework of the Individuals with Disabilities Education Act (IDEA), emphasizing Free and Appropriate Public Education (FAPE) and the Least Restrictive Environment (LRE). The research was conducted in a medium-sized rural district high school.

The overarching research question was: Based on student test scores, ESSA data, surveys, and interviews with content area teachers, ESE teachers, paraprofessionals, support facilitators, and administrators, how effective are self-contained and …

Investigating The Proviral And Immunogenic Effects Of Sars-Cov-2 Accessory Protein 7a, Grant Michael Hawkins

Dissertations

SARS-CoV-2 and related sarbecoviruses encode a set of accessory proteins (3a, 3b, 6, 7a, 7b, 8, 9b, and 10) that control host responses to infection and promote virus growth. Of these accessory proteins, 7a is set apart by its intracellular localization near coronavirus (CoV) budding sites and its incorporation into secreted virions. Initial studies utilizing a virus-like particle (VLP) system identified significant proviral effects mediated by 7a, but the system lacked the context of an actual CoV infection. To investigate 7a functions during CoV infections, we constructed recombinant Mouse Hepatitis Viruses (rMHV strain A59) that express 7a genes. Comparative infections …

Anchored Networks: Navigating Formal And Informal Pathways To Access Educational Resources In Transient And Military Families, Lara Ray

Dissertations

This study examines how Navy families in San Diego establish and use formal and informal networks to access educational resources for their children following relocation. Grounded in social capital theory, the research employed a multiple-case study approach, integrating data from interviews, focus groups, and digital analysis of Navy-affiliated social media platforms. The study explores how parents navigate these networks to promote their children’s academic success, with particular attention to key decision-making moments, resource negotiation, and equity considerations. Participants included Navy spouses from diverse ranks (E-3 to O-6) and socioeconomic backgrounds, providing insight into disparities in resource access. Findings reveal that …

Middle School Teacher Perceptions Of Digital Game-Based Learning In A 1:1 School District, Brennen Knight

Dissertations

This study examines middle school teachers' perceptions of Digital Game-Based Learning (DGBL) within a 1:1 school district. In this district, each student is provided with a personal digital device. With the increasing integration of technology in education, DGBL has been recognized as a tool that enhances student engagement, fosters differentiated learning, and improves achievement. However, despite its potential benefits, teacher adoption of DGBL varies widely due to personal beliefs, pedagogical challenges, and institutional barriers. Guided by the Technology Acceptance Model (TAM) and Rogers’ Diffusion of Innovation Theory, this qualitative multiple-case study explores how middle school teachers perceive, implement, and what …

High School Students' Mathematics Experiences And Mathematics Learner Identities In A Rural Georgia Town: A Qualitative Study Using Autophotography With Photo-Elicitation, Wesley Cooper

Dissertations

This study examines the mathematics experiences (MEs) and mathematics learner identities (MLIs) of high school students in a rural Georgia town, addressing the underrepresentation of rural perspectives in mathematics education through an asset-based lens. Using autophotography with photo-elicitation, ten participants captured images reflecting their MEs, MLIs, and recommendations for improvement. Semi-structured interviews and focus groups along with two mini-cases amplified participant voices, guided by the frameworks of Four Faces of Mathematics Learner Identity (4F), Content Learning and Identity Construction (CLIC), and Critical Rural Theory (CRuT). Findings highlight how rural students’ MEs and MLIs are shaped by both the strengths of …

The Lived Experiences Of Disabled Students In Inclusive Classrooms, Tanner Mizel

Dissertations

This dissertation explores the lived experiences of disabled students in inclusive classrooms, with a focus on those participating in extensive support needs (ESN) programs. Intentionally inclusive of students who communicate through diverse methods, including augmentative and alternative communication devices, picture exchange communication systems, American Sign Language, and other nonspoken forms, this phenomenological case study centers the perspectives of students in one middle school’s ESN program through mobile interviews and reflective document analysis. Student perspectives are triangulated through surveys reflecting the perspectives of parents, guardians, and school staff. Grounded in disability studies in education, this study challenges deficit-based approaches to inclusive …

A Phenomenological Study Of Southern California Charter School Leaders’ Perceptions Of Creating An Inclusive School Culture, Barbara Hale

Dissertations

Purpose: The purpose of this phenomenological study was to identify and describe the culturally responsive leadership practices that charter school leaders use to create a culture of inclusiveness. A second purpose of the study was to identify and describe the supports and barriers charter school leaders perceive affect the development of a culture of inclusiveness for students. Methodology: This study identified and described the culturally responsive leadership practices implemented by charter school leaders to create a culture of inclusiveness and identify the supports and barriers the leaders perceived to affect the development of the inclusive culture. I interviewed 10 participants …

Does Artificial Intelligence Bias Exist In Mortgage Underwriting Software? Investigating Bias, Regional Disparities, And Fair Ai Models, Dorian Cornelius

Dissertations

This quantitative study closely emulated Zou and Khern's (2022) analysis of AI Bias in Mortgage Applications. They used the Home Mortgage Disclosure Act (HMDA) dataset from the Federal Financial Institution Examination Council's (FFEIC) website to review mortgage loan data from 2019 to determine if there was bias in the AI mortgage application approvals. Those researchers concluded that bias does exist in the AI mortgage underwriting software. Since their study, research has demonstrated that discrimination continues to exist in AI software. Therefore, this research expands on Zou and Khern’s study to determine if there are differences in the mortgage loan approval …

Examining The Value Of Industry-Recognized Certifications In Illinois Secondary Career And Technical Education Programs, Nancy Awdziejczyk

Dissertations

The goal of career and technical education (CTE) is to equip students for success in postsecondary education and the workforce. This study investigated the integration and impact of industry-recognized certifications (IRCs) within CTE programs in Illinois, particularly within the framework of Perkins V legislation. The research aimed to determine how IRCs enhance employability, increase starting salaries, and support career advancement for high school students through aligning CTE curricula with the demands of the current labor market.

The study was initiated due to difficulties in identifying valuable certifications for CTE programs stemming from the excessive number of certifying organizations and unclear …

Evaluating Sympton Clusters In First-Time Ischemic Stroke Survivors Who Discharge From The Hospital To Home, Paula De La Pena

Dissertations

The purpose of this study was to examine symptoms and relationships between those symptoms in first-time ischemic stroke survivors who discharge home after their initial stroke. Current measurement of recovery after stroke places emphasis on the physical aspects of recovery when current literature suggests that other, more subtle symptoms may be equally contributory to recovery. This descriptive, exploratory research study was conducted via a secondary analysis of both structured and unstructured data in a study cohort of 115 first-time ischemic stroke survivors from a tertiary academic medical center in the Midwest. Unstructured clinical notes were analyzed for the presence of …

Teaching Since 2020: Inhabiting Professionalization, Autonomy, And Classroom Teaching, Melissa Fisher

Dissertations

This study explores teacher professionalization Since 2020 by examining control over teachers’ work as constructed by classroom teachers. Using a conceptual framework combining the teacher disempowerment perspective, inhabited institutionalism, and professionalization, I focus on the question: Given the recent years of upheaval the profession of education has sustained, how are teachers inhabiting the role of "professional teacher," particularly regarding control over their own work? This qualitative study utilizes semi-structured interviews with fourteen teacher participants in an Indiana public school district. This study finds that participants are constructing a new Since 2020 teaching reality. Participants converged on professional challenges including disruptive …

Examining The Current Utilization Of Conceptual Data Modeling In Database Modeling Practices: Mixed Methods Research, Abhishek Sharma

Dissertations

The database system is essential to modern life and helps us in our day-to-day existence, even though it is invisible to us. The most optimal way to architect a new but efficient database is a modeling technique called conceptual data modeling. Despite this importance, research studies have suggested a divergence between actual practice and the ideal expectation from practitioners. Therefore, it was imperative to establish the ground truth in this context and explore the reasons behind the gap between practice and expectation. This mixed-method study used a survey and interviews to establish that only a small fraction of practitioners consistently …

The Impact Of Quality Management Principles On Army Aircraft Maintenance Outcomes, Matthew S. Caporossi

Dissertations

Purpose: The purpose of this qualitative phenomenological study was to identify and describe the perceptions of organizational managers on the impact of quality management principles on helicopter maintenance outcomes at the California Army National Guard’s Aviation Classification Repair Activity Depot (AVCRAD). This study also explored the perceptions on the organizational culture as it pertained to leadership and employee engagement of the International Organization for Standardization (ISO) 9001 quality management systems.

Methodology: This qualitative phenomenological research examined the perceptions of Army aviation managers regarding specific ISO principles of leadership and

improvement on AVCRAD maintenance outcomes. The researcher conducted open-ended qualitative interviews …