Digital Commons Network^™

Virtual Reality In Esl Teaching And Learning In A Hybrid Learning Environment In The United Arab Emirates, Basma Abdulla Abri

Dissertations

This study examines the impact of Virtual Reality (VR) on the oral proficiency of EFL learners in the UAE context, with exploring the instructors and students’ perspectives on using VR as a language learning tool. The study involved 44 Emirati higher education students enrolled in an English Communications Program divided into a control group using traditional methods, and an experimental group using VR tools for communicative activities. Data collection employed mixed-methods research through questionnaire surveys involving college students and interviews with EFL instructors over a ten-week period. According to the findings, the experimental group demonstrated higher oral proficiency than the …

Development And Characterization Of Sustainable Aluminum Metal Matrix Composites With Date Palm Agro-Residues As Reinforcement, Ansar Kareem

Dissertations

Aluminum Matrix Composites (AMCs) are extensively used in various industrial applications owing to their exceptional mechanical, material, and tribological properties. This led to the development of AMCs with every possible aluminum alloy as matrix, incorporated with various reinforcement materials to achieve desired material properties. There has been an increasing trend in the utilization of agricultural and industrial waste products as reinforcement material in AMCs. Date palm trees produce huge quantity of agricultural waste in different forms. Usually, these wastes are burned or disposed of in landfills which cause environmental pollution. Date palm agro-wastes can be incinerated to produce date palm …

Trustworthy Federated Learning Framework For Secure, Efficient, And Quality-Aware Distributed Ai, Asadullah Tariq

Dissertations

Federated Learning (FL) emerged as a significant advancement in the field of Artificial Intelligence (AI), enabling collaborative model training across distributed devices while maintaining data privacy. As the importance of FL and its application in various areas increased, addressing trustworthiness issues in its various aspects became crucial. In the FL process, clients contribute updates computed on their local datasets, which the server aggregates to iteratively refine the global model. However, not all client data may be relevant to the learning objective, and incorporating updates from irrelevant data can harm the model's performance. The selection of training samples significantly impacts model …

Problems In Extremal Graph Theory And Spectral Graph Theory, Fareeha Jamal

Dissertations

Spectral graph theory is a subfield of algebraic graph theory that studies the matrices associated with graphs. It lives at the nexus of Linear Algebra and Combinatorics. Many intriguing results in the domains of Matrix Theory and Combinatorics have come from studying the eigenvalues of graph matrices; in fact, several open problems in both areas have been resolved. Beyond its theoretical appeal, spectral graph theory has found meaningful applications in theoretical chemistry, particularly in the mathematical classification of chemical graphs. These classifications underpin quantitative structure–property relationships (QSPRs), facilitating the prediction of physicochemical properties such as enthalpy of vaporization, molar refractivity, …

Rehabilitation Of Reinforced Concrete Columns Pre-Damaged By Corrosion Using Advanced Composite Materials, Feras Farid Abu Obaida

Dissertations

Reinforced concrete (RC) columns exposed to aggressive environments are highly susceptible to corrosion-induced deterioration, resulting in significant reductions in load-carrying capacity. This research investigates the structural performance of RC circular short columns with varying levels of corrosion damage and evaluates the effectiveness of two composite-based repair techniques, namely carbon fabric-reinforced cementitious matrix (C-FRCM) and carbon fiber-reinforced polymer (C-FRP) composites, combined with concrete cover replacement. The study aims to establish these methods as practical solutions for rehabilitating corrosion-damaged columns under concentric and eccentric loading conditions. The experimental program included 30 RC column specimens tested in two phases. Phase I involved thirteen …

How Do Emirati University Students Develop Their Academic Biliteracy? A Mixed-Method Study, Eman Kamel Rababa

Dissertations

Framed by Hornberger’s continua of biliteracy model, this study investigated the developmental dynamics of academic biliteracy among Emirati university students. The research employed a sequential mixed-methods design, conducted across three public universities in the UAE. In the initial qualitative phase, interview data were collected from 30 students. Informed by these findings and the extant literature, a quantitative survey was then developed and administered to a sample of 299 students from various disciplines. The qualitative data were analyzed using reflexive thematic analysis, while the quantitative data were examined using advanced statistical analyses, including structural equation modeling. Three primary themes emerged from …

Analyzing Sea Level Rise Scenarios Impact On The Mobility, Infrastructures, Environment Of Abu Dhabi And Defining Solutions By Creating A Digital Twin Using Gis And Game Engine, Justine Sylviane Lucie Sarrau

Dissertations

This dissertation investigates the potential impact of future sea level rise (SLR) scenarios on the city of Abu Dhabi. With climate change, many coastal towns are at risk of experiencing this type of natural hazard. Currently, no precise scenario simulations have been developed, mainly due to the use of low spatial resolution elevation data. Additionally, the difficulty in understanding the real impacts persists when analyses rely solely on traditional cartography and GIS methods. This dissertation aims to advance the field by offering a new approach, which involves creating a comprehensive dynamic 3D simulation with dynamic flowing water. This model, defined …

Ai-Enabled Multi-Layer Security Operations: A Combined Siem, Ids, And Threat Intelligence Model For Adaptive Cyber Defense, Mohamad Khayat

Dissertations

This dissertation presents a comprehensive framework for the evolution of Security Operation Centers (SOCs) through the integration of advanced artificial intelligence (AI), blockchain, and optimization techniques. Motivated by the increasing complexity of cyber threats and the limitations of traditional reactive SOC strategies, this work begins with a systematic literature review that identifies critical gaps in current SOC operations. Based on these insights, a reference architecture is proposed to guide the integration of intelligent components into SOC environments. To address the challenge of secure and trustworthy information sharing, a blockchain-based threat intelligence platform is developed, leveraging Byzantine Fault Tolerance and Zero-Knowledge …

Jet Impingement And Vortex/Swirl Cooling Of Different Inlet And Outlet Geometrical Configurations For Turbine Blade Leading Edge Cooling, Irfan Ahmad Sheikh

Dissertations

Gas turbine blades operate in extreme environments, exposed directly to high-temperature combustion gases that cause severe thermal stresses, weaken material integrity, and may lead to structural failure. Proper cooling is crucial to lower blade temperatures, reduce thermal stresses, prevent failure, and improve overall engine efficiency. This work presents a detailed numerical study of various cooling configurations by applying two advanced leading-edge cooling methods, jet impingement and swirl cooling, across different inlet mass flow rates and jet Reynolds numbers (Rej) ranging from 1,000 to 20,000 to evaluate their cooling performance.

Several advanced leading-edge cooling configurations are proposed and compared with the …

Understanding Middle Managers In Community Colleges, Mason Salazar

Dissertations

This dissertation explores the lived workplace experiences of non academic middle managers at community colleges, a group often overlooked in higher education research. Using a phenomenological approach, this study draws on semi-structured interviews with eleven directors and managers to highlight how these professionals navigate their campus environments, operational demands, and student needs. Framed by Max Weber’s theory of bureaucracy, the findings underscore the dual roles middle managers play, as organizational lynchpins and leaders and as advocates for students, all while operating within constrained organizational structures. Key themes include varied levels of institutional knowledge, differential access to professional development, and constrained …

Analysis Of Antibody Affinity Maturation And Thermal Stability Of Proteins Using Photophysical Approaches, Claire Baxter

Dissertations

Engineered antibodies (Abs) have found applications in disparate fields such as enzyme catalysis and medicinal therapeutics because of their exquisite binding affinity and specificity. To engineer antibodies for these purposes, a firm understanding of the underlying mechanisms that control Ab affinity and specificity is needed, so these properties can be tightly controlled and adapted to the application at hand. My research characterized the binding site of the anti-fluorescein Ab 4-4-20 using an array of biophysical techniques and gives insight into the binding site interactions that give rise to both affinity and specificity. We utilized Fab fragments of the anti-fluorescein Ab …

The Effects Of Targeted Interventions On Student Engagement With Feedback: A Meta-Analysis, Andy A. Accettola

Dissertations

ABSTRACT This meta-analysis examines the effects of classroom interventions aimed at enhancing student engagement with feedback in K–12 and higher education settings. Drawing on the framework developed by Winstone et al. (2017), interventions were categorized into four major feedback engagement categories and 14 subcomponents. A systematic review identified eligible experimental studies published between 2014 and 2023, each reporting outcomes relevant to student feedback engagement. Effect sizes were calculated using standardized mean differences, and subgroup analyses explored the relative influence of intervention categories, subcomponents, and moderators. Findings from this meta-analysis indicate that targeted interventions to enhance student engagement with feedback generally …

Parental Autonomy Support And Children’S Affect As Predictors Of Children’S Stem Engagement In An Informal Educational Context, Bianca Martins Aldrich

Dissertations

In this project, we examined relations between parental talk and children’s affect on children’s STEM talk during an engineering-related activity (i.e., tinkering) in a local children’s museum. We characterized children’s affect in terms of valence (positive or negative) and activation (activating or deactivating), and parental talk was characterized as autonomy supportive or directive, as well as STEM-related or not. Parents and their 4- to 10-year-old children were recruited at the entrance of the Tinkering Lab exhibit at Chicago Children’s Museum. Parents and children were video and audio recorded during the activity. We coded parents’ and children’s behaviors using a time-sampling …

Robust Ai Solutions For Financial Markets Through Generative Modeling, Dynamic Graph Learning, And Reinforcement-Based Portfolio Optimization, Jingyi Gu

Dissertations

Financial markets are inherently uncertain and dynamic, driven by complex factors such as macroeconomic signals, investor sentiment, and evolving inter-asset relationships. While machine learning has advanced financial modeling, existing approaches often fall short in addressing the real-world intricacies of finance. This dissertation confronts two critical challenges, human-driven stochasticity and risk-intensive decision-making under real-world trading constraints, while seizing a pivotal opportunity, the structural dynamics of evolving financial systems. These elements are foundational to advancing robust and practical financial intelligence.

To this end, this dissertation develops a unified framework for robust financial modeling and decision-making. The framework is architected as a progressive, …

Large-Scale Graph Algorithms And Applications With An Emphasis On Fintech Data, Fuhuan Li

Dissertations

Graph algorithms are essential analytical tools with applications spanning cybersecurity, biology, social media, and increasingly, financial technology (FinTech). The complex and interconnected nature of financial data, particularly in cryptocurrency networks, presents unique opportunities for graph-based analysis in fraud detection and anomaly identification.

This dissertation presents the design and implementation of scalable graph algorithms tailored for large-scale networks, with particular emphasis on FinTech applications. The primary contributions include: (1) novel cover-edge based triangle counting algorithms that significantly reduce computational overhead through breadth-first search preprocessing, achieving substantial speedups over traditional methods and dramatic communication reduction in distributed settings, (2) optimized parallel implementations …

Bodipy-Based Photocages For The Controlled Release Of Hydrogen Sulfide And Persulfides, Yanmei Li

Dissertations

Reactive sulfur species (RSS) such as hydrogen sulfide (H2S) and hydropersulfides (RSSH) are crucial mediators in a variety of physiological and pathological processes. Their regulatory roles span from maintaining cellular redox balance to influencing signaling pathways critical for homeostasis and stress responses. This dissertation investigates H2S and RSSH as biologically important molecules and explores the development of boron-dipyrromethene (BODIPY)-based photocages for its controlled, light-triggered release. Given H2S and RSSH's critical role in redox regulation and cellular protection, achieving spatiotemporal control over its delivery is essential for both therapeutic and research applications. BODIPY scaffolds offer favorable photophysical properties, including visible-light activation …

Reduced Order Models Of Hydrodynamically Interacting Flapping Wings, Jose Pabon

Dissertations

Fish schools exhibit a collective behavior and self-organization that is mediated by hydrodynamic interactions between individual fish. However, the long-time evolution of hydrodynamically interacting collectives is challenging to investigate due to the persistent influence of long-lived vortical structures, and the high-resolution requirements of direct numerical simulation at large Reynolds numbers. Reduced-order models have therefore played an important role in theoretical investigations of collectives of swimming bodies. The main results detailed herein are several new reduced-order models of swimmers that self-propel by flapping, i.e., by executing a prescribed periodic rigid body motion. The models are extensions of a discrete-time dynamical system …

Optimizing Hip And Knee Assistance For Walking And Sit-To-Stand Transitions: An Intrinsic Muscle Mechanics Based Predictive Approach, Neethan Ratnakumar

Dissertations

As the global population ages, the demand for wearable assistive technologies continues to rise, driven by their potential to enhance mobility and independence in older adults. Effectively designed controllers for lower-limb exoskeletons to assist sit-to-stand (STS) and walking are crucial for delivering efficient, safe, and comfortable assistance during daily activities. Traditionally, controller optimization involves biomechanical modeling and user-specific customization. Musculoskeletal simulations play a central role in this process by providing insights into human-exoskeleton interaction dynamics, thereby informing and refining control strategies.

This work presents a simulation-driven approach for developing exoskeleton controllers for walking and STS using two distinct methods: optimal …

Developing An Instrument To Measure Teacher Attitudes Toward Multilingual Pedagogies, Lauren H. Ramers

Dissertations

In an increasingly globalized world, substantial numbers of multilingual learners occupy K–12 and higher education spaces bringing diverse linguistic resources that, when intentionally and appropriately leveraged, can significantly enhance English language learning outcomes. Multilingual pedagogies, which honor and build upon students' full linguistic repertoires, are essential for fostering equitable and inclusive learning environments. This quantitative exploratory study investigated teachers' attitudes toward multilingual teaching with the goal of developing a reliable survey instrument—the Multilingual Pedagogy Scale (MPS)—to measure how teachers perceive language learning in multilingual classrooms and what they report doing in their classrooms.

First, a review of the research helped …

Racial Identity And Belonging Among Asian American Undergraduate Students In The Midwest, Seema M. Dahlheimer

Dissertations

Asian American students are often deemed overrepresented in higher education, leading to inequities in admissions, scholarships, and student support. This perception feeds and is fed by the model minority stereotype, which characterizes Asian Americans as hard-working and high-achieving and creates intense pressure to succeed academically (Poon et al., 2016). In addition, Asian American college students often experience racism and xenophobia, which can undermine their sense of belonging on campus. However, in the Midwest, where their immigration is more recent and conversations about race are often framed in terms of Black and white, Asian Americans often feel invisible and othered (Lee, …

Biophysical Effects Of Altered Myosin Binding Protein Stoichiometry In Atrial Myofilaments, Kelly N. Araujo

Dissertations

Cardiomyopathies, such as hypertrophic and dilated subtypes, are leading causes of heart failure and are often driven by genetic mutations that disrupt the structure and function of the cardiac sarcomere. While much of the research has focused on ventricular involvement, the role of atrial sarcomere dysfunction remains unexplored. The regulation of contractile function by sarcomeric proteins in the atria remains poorly understood, especially the impact of protein stoichiometry among myosin binding proteins. Cardiac myosin binding protein-C (cMyBP-C) and its atrial paralog, myosin binding protein H-like (MyBP-HL), have been shown to have a stoichiometric relationship within the atrial sarcomere. These two …

Archival Articulations Of Belonging: Resistance, Reimagination, And Resilience In School And In Incarceration, Caroline Hastings

Dissertations

Belonging is a universal desire, providing purpose and comfort, that supports our ability to survive and triumph through difficulty. A lack of belonging can impact one’s likelihood of becoming incarcerated. In turn, incarceration stigmatizes individuals and disrupts connections with family, friends, and community members. This study of individual’s experiences of belonging analyzed reflective written accounts created during incarceration. This phenomenological qualitative examination of belonging for formerly and currently incarcerated individuals, disproportionately people of color and individuals with disabilities, sought to deepen our understanding of belonging as a force in their lives. In the United States, high rates of incarceration impact …

Adapting To Change: Adn Faculty Perspectives About The Future Of Adn Education: A Qualitative Case Study, Linda D. John

Dissertations

The purpose of this qualitative single case study was to offer more insight into how the adoption of the BSN as the entry-level for nursing practice affects the future ADN education and what the change means for ADN faculty at multiple programs throughout regions of the United States. Eleven ADN faculty were sampled to acquire their perspective about this phenomenon.

Joint Kinematics And Kinetics During Vertical Jump Landings With Progressively Increasing External Loads, Darcie L. Yount

Dissertations

This study examined sagittal and frontal plane kinematics and kinetics during countermovement jump (CMJ) landings performed with either a traditional barbell (BB) or a hexagonal bar (HEX) across increasing submaximal loads in recreationally active males. Generally, hip and knee flexion angles and joint mean angular velocities decreased as loads increased. Hip extension and knee flexion moments increased as load increased up to 20 kg, at which point these values decreased. Performing the CMJ with the HEX exhibited increased frontal plane stability compared with the BB group. Additionally, the BB group exhibited stiffer landing strategies, with decreased sagittal plane joint angles …

Understanding Structure-Property Relationships Within Polyolefin-Derived Vitrimer Systems, Mikaela Sadri

Dissertations

Polyolefins are extremely ubiquitous materials due to their satisfactory material properties, ease of synthesis, and low cost. Unfortunately, their extensive use has led to a global plastic waste mismanagement problem. As such, notable efforts have recently focused on converting these commodity polymers into vitrimers, or dynamic networks, to extend their use-life and tailor their properties. However, the fundamental polymer physics of these emerging materials, remain largely underexplored, hindering their widespread implementation. To address this challenge and enable a more sustainable future, the overarching goal of my dissertation research is to understand the fundamental structure-property relationships within complex polyolefin-derived vitrimer systems. …

Teaching Students Who Have Been Identified With Autism In The Private Piano Teaching Studio: An Application Of General Music Resources And Interviews With Specialists In The Field, Joy Parker

Dissertations

This dissertation is a practical resource for private piano teachers seeking to gain a better understanding of teaching students with autism. Resources used in general music instruction of students with autism were consulted, and relevant information was adapted for the private piano setting. Additionally, resources that are tailored to private piano teaching of students with an identified disability were consulted.

Interviews with three individuals who have experience working with individuals with autism were conducted, and methods and strategies that they found to be most successful were ascertained. One of the interviewees was Dr. Derek Polischuk, Professor of Piano and Director …

Establishment Of Neonatal Sepsis Predictors Utilizing Non-Invasive Monitoring Techniques, Dalton Janssen

Dissertations

Neonatal sepsis remains one of the leading causes of global neonatal mortality. Reactionary approaches for diagnosis and treatment have dominated the tactics in addressing neonatal sepsis but clinical intuition is an untapped resource that could lead to earlier prediction of sepsis onset. Nurses and other staff with specialized training and experience who have served as routine caregivers for a specific patient are able to identify when the patient’s status is altered. This clinical intuition may be substantiated by referencing specific patient trends in non-invasive measures over time. This retrospective, exploratory study examined whether variation in non-invasive monitoring variables could serve …

Exploring Moral Distress In Hospital-Based Nurse Case Managers: A Qualitative Descriptive Study, Mary Margaret Leas

Dissertations

Moral distress is a well-known phenomenon among hospital-based bedside nurses that is damaging and dangerous to patients, nurses, the healthcare system, and society. There is a gap in the literature related to the experience of moral distress (MD) among hospital-based nurse case managers. The purpose of this qualitative research study was to understand the experience of MD for the hospital-based nurse case manager and identify triggering events and consequences of MD. The following research questions guided this study:

Q1 What is the experience of MD among hospital-based nurse case managers?

Q1a What do they identify as causes or precursors of …

Mexican Americans’ Attitudes Toward Mexican Immigrants In The United States, Sandra Daisy Espinoza Montes

Dissertations

The United States (U.S.) has often been described as a nation of immigrants. Among the 40 million immigrants in the U.S., Mexican-descent individuals comprise 25% of the overall immigrant population, positioning them as the largest immigrant group in the country. Additionally, Mexican Americans constitute 63% of the Latinx population, making them the largest minoritized ethnic group in the U.S. Considering that Mexican immigrants and Mexican Americans have a significant presence in the country, scholars have called for additional research on attitudes towards Mexican immigrants (Byrne & Dixon, 2016; Flores et al., 2022). However, much of the existing literature on attitudes …

Measurements And First Principles Calculations On The Non-Centrosymmetric Superconductor Aupb3, Meena Shrestha

Dissertations

AuPb₃ is a non-centrosymmetric superconductor that crystallizes in a tetragonal structure and undergoes a superconducting transition at 4.4 K. Non-centrosymmetric superconductors that lack inversion symmetry are predicted to have an admixture of spinsinglet and spin-triplet symmetry induced by strong antisymmetric spin-orbit coupling (ASOC).

In this work, we investigated the normal and superconducting properties of AuPb₃. We also carried out the Density Functional Theory (DFT) calculations to study the strength of ASOC and its impact on vibrational and electronic properties. A high-quality polycrystalline sample of AuPb₃ was grown and characterized by powder x-ray diffraction, scanning electron microscopy, …