Digital Commons Network^™

High Frequency Dc-Dc Converter Design Optimization, Modeling And Control Based-Wbg Technology., Salah Ahmed Abdullah Eltief

Electronic Theses and Dissertations

The performance of DC-DC power converters is a cornerstone of modern electric vehicle (EV) powertrains, directly governing overall system efficiency, size, cost, and reliability. This dissertation presents a comprehensive performance analysis and optimization of DC-DC converter topologies to determine the most suitable design for high voltage EV applications. The evaluation rigorously compares efficiency, power losses, and physical size under a range of harsh operating conditions. A primary objective is to leverage Wide Bandgap (WBG) semiconductors, specifically Silicon Carbide (SiC), to push the performance boundaries of power conversion. While SiC devices are known for their superior material properties, a clear understanding …

Museums In Public Libraries: An Ethnographic Case Study Of The Blair-Caldwell African American Research Library, Yadira Y. Quintero

Electronic Theses and Dissertations

Access to information is a human right, and this thesis explores the benefits and challenges of integrating museums into public libraries by conducting an ethnographic case study of the Blair-Caldwell African American Research Library. The study's findings highlight the complexities of integration. The biggest benefit is the increased access to museum collections, information, and resources. However, challenges arise from the lack of cohesion within the museum and library disciplines, as well as strained community relations. Engaging the community is crucial for successful collaboration, emphasizing the importance of a bottom-up approach that allows for active participation. Integrating museums into public libraries …

Doughnut Economics And Strong Sustainability: Rethinking The Role Of Financial Investment, Isabelle Pierotti

Electronic Theses and Dissertations

This thesis investigates how private investment could align doughnut economic framework. Doughnut economics is a strong sustainability economic framework where the economy operates within planetary boundaries while ensuring social equity. Theories of sustainable development, weak sustainability, and strong sustainability are discussed to provide theoretical context for doughnut economics and mainstream economics. The analysis concludes that conventional, profit maximizing private investment does not support a doughnut economics system by supporting the depletion of natural resources and exacerbating social issues. Sustainable mainstream investment also fails to support a doughnut framework. Lastly, while impact investment is theoretically committed to social and financial returns, …

An Auto-Criticism: Exploration Of Professional Development For Secondary Science Educators, Mellissa Ann Pfaff

Electronic Theses and Dissertations

This auto-criticism investigates the benefits of experiential professional development for science educators by examining the reflective journey of one teacher-researcher—me—through multiple immersive learning experiences. Using narrative journaling and qualitative analysis, this study captures the influence of these experiences on my identity, instructional design, and ability to create experiential learning opportunities for students.

Rather than approaching professional development as a checklist of strategies, this research seeks to illuminate how deeply engaged, hands-on learning can transform teaching from routine delivery to embodied practice. Thematic coding revealed shifts in curriculum planning, increased responsiveness to student inquiry, and renewed clarity around the purpose of …

Archaeological Predictive Meta-Modeling In Pre-Columbian Mexico, Peter Stamm

Electronic Theses and Dissertations

Archaeological Predictive Modeling stands firmly as an important tool for Archaeologists to predict undiscovered sites from civilizations all across the globe. While powerful, this methodology is not without its own set of qualms. Striking a balance between pure a data-driven approach while also observing leading expert theories can be a complicated task. Going further, deciding on the specific domain of features to emphasize or overlook can be a challenge within itself, as one misstep can drastically change the output of model, sometimes for the worst. In addition, creating models that can expose their reasoning process can be rather difficult to …

Reproducibility In Modeling Of Knee Joint Mechanics, Maryam Nazem

Electronic Theses and Dissertations

Computational modeling of knee joint biomechanics can provide valuable insights into joint function, injury mechanisms, and patient outcomes, and can support surgical planning and informed clinical decision-making. However, achieving consistent and repeatable results, or reproducibility, is a significant challenge that affects the credibility of these models. This thesis addresses reproducibility through two studies related to the KneeHub Project, which is a multi-institutional collaboration designed to investigate reproducibility in finite-element modeling of the knee.

The first study involved model benchmarking, where predicted results of the calibrated models were compared with the experimental data to evaluate model reproducibility. While all models replicated …

The Resonance Of Desire: A Sonic Exploration And Guide To Recreating Disney’S Signature ‘I Want’ Songs, Aiyanna E. Riley

Electronic Theses and Dissertations

This thesis explores the sonic architecture of Disney’s Renaissance-era “I Want” songs and develops a framework for recreating their signature production style. This study analyzes how vocal timbre, microphone choices, layering, stereo placement, and mixing strategies contribute to the immersive qualities that define the Disney sound. Drawing from historical accounts, interviews with industry professionals, and technical literature, the thesis documents production practices unexamined in scholarly work. Inspired by David Gibson’s The Art of Mixing, my analyses prioritize spatial and textural qualities in Disney mixes, highlighting how sound design shapes narrative impact. The study culminates in two original compositions modeled …

The Effectiveness Of A First-Year Experience Course: A Case Study From A Public Regional University In The Central United States, Taler J. Alexander

Electronic Theses and Dissertations

Student retention has become an increasingly popular topic for colleges and universities as they look for ways to keep students amid ever-changing budget climates. Research shows that high quality first-year experience (FYE) courses can provide crucial support to new students as they enter the college or university. Additionally, many researchers have found that supporting students through their transition to a new college environment, developing their sense of belonging, and helping them get involved on campus lead to increased student retention. The purpose of this study was to explore the curriculum, format, and delivery of the FYE course at Blue University …

The Heart Of Policing: Exploring The Essence Of The Phenomenon Between Organizational Culture And Police Officer Job Satisfaction, Charles C. Palmer

Electronic Theses and Dissertations

The purpose of this transcendental phenomenological qualitative study was to explore the essence of the phenomenon between organizational culture and police officer job satisfaction among rural law enforcement agencies in Oklahoma. Retaining police officers has become an increasingly challenging task for law enforcement organizations across the United States, as high turnover, costly recruitment, and voluntary resignations continue to strain departments. While previous research has primarily examined demographic and occupational variables influencing satisfaction, limited attention has been given to how organizational culture affects the lived experiences of U.S. police officers. Guided by Edgar Schein’s organizational culture theory, this study examined how …

Leading Beyond The Lecture: A Case Study Exploring How Community College Students Experience Their Instructors’ Positive Leadership Strategies, Mandy Morrison

Electronic Theses and Dissertations

Positive leadership, an approach to leading individuals to the point of flourishing, has been studied in corporate contexts. While the student-to-instructor relationships only distantly compare to the employee-to-supervisor dynamics, the relationships and power differential have similarities, making the pillars of positive leadership relevant in the context of higher education. Given the critical nature of student success to stakeholders in higher education and the students themselves, discovering instructor strategies that enhance student success can demonstrate an upward spiral of positivity that extends from the student, to the instructor, to the college, and ultimately to the community. Framed by leader-member exchange (LMX) …

Understanding The Retention Of Alternatively Certified Teachers: Key Factors And Insights, Donna M. Hardy

Electronic Theses and Dissertations

The problem addressed in this study was the high attrition rate of alternatively certified teachers

who often exit the classroom at greater rates than traditionally trained teachers, particularly

within their first 5 years of teaching. The purpose of this study was to explore the lived

experience of alternatively certified teachers to identify the support, conditions, and leadership

practices that contributed to their persistence. A qualitative phenomenological study was used,

with data collected from 14 alternatively certified teachers who work in a Central Texas school

district, utilizing semistructured interviews. Data collection methods included interviews,

member checking, and researcher field notes. Research …

How School Mentors Build Self-Efficacy In Novice Teachers: A Single Case Study, Christina Olga Sanchez

Electronic Theses and Dissertations

This qualitative single case study with embedded units explored how school mentors build selfefficacy in novice teachers across elementary, middle, and high school settings within a single public school district in Texas. Grounded in Bandura’s self-efficacy theory, which identifies four sources of self-efficacy: mastery experiences, vicarious experiences, verbal persuasion, and emotional and physiological states, this study examined the specific strategies mentors use to build self-efficacy and foster confidence and instructional competence in novice teachers. Data were collected through semistructured interviews with eight experienced educators formally designated as mentors. Thematic analysis was employed to identify patterns in mentoring practices and their …

Breaking Barriers: Mentorship Pathways For Hispanic Women In Leadership Roles, Ana Paola Gonzalez

Electronic Theses and Dissertations

This study aimed to understand the unique lived experiences of 10 Hispanic Latinas serving in leadership roles in 2-year community colleges in Texas. As the graduation rate of Hispanic women increases, institutions must identify mentorship programs that motivate women who continue to graduate to seek leadership positions within their institutions. Through life stories and lived experiences, the study's findings illustrate that mentorship is essential to creating, but that self-determination and self-advocacy also make it possible to find paths to leadership. Through thematic analysis, three themes emerged from the data: identity and representation, mentorship and support structures, and resilience and advocacy. …

Exploring The Influence Of Self-Efficacy And Cultural Identity On Black Teacher Retention, Cicely Kelly Ward

Electronic Theses and Dissertations

This study addressed the persistent challenge of retaining Black educators in racially diverse U.S. secondary schools. The specific problem was a knowledge gap regarding how the lived experiences of Black teachers connect their self-efficacy and cultural identity to retention. The purpose of this study was to explore these dynamics to inform the development of more effective support strategies. This qualitative phenomenological study involved semistructured interviews with 10 Black secondary school teachers who had 3 or more years of experience in the Southeastern region of Texas. The researcher analyzed the interview data using a thematic analysis framework to identify patterns of …

The Effect Of Perceived Principal Leadership Styles And School Type On Elementary Teacher Self-Efficacy, Karen M. Gonzalez

Electronic Theses and Dissertations

The purpose of this study was to explore the effect of perceived principal leadership styles and school type on elementary teachers’ self-efficacy. The study examined two research questions. The first examined differences between teachers’ self-efficacy in Title 1 and non-Title 1 schools, and the second examined differences in teacher self-efficacy and perceived principal leadership styles (authoritarian, democratic, and laissez-faire). The convenience sample included 129 elementary teachers from social media teacher groups that taught in various Title 1 and non-Title 1 school districts. I used a quantitative, causal-comparative method to collect data and survey questionnaires that identified trends in leadership styles …

Effectiveness Of Ai-Powered Language Learning Tools In The Workplace, Iswariya Baskar

Electronic Theses and Dissertations

This dissertation explored the experiences of multilingual employees with AI-powered language learning tools in financial and technology firms across the United States. As multilingual communication becomes increasingly vital in the workplace, the integration of artificial intelligence (AI) offers promising support in language acquisition and cross-cultural collaboration. The purpose of this basic qualitative study was to explore how AI-powered language learning tools influence the acquisition and retention of foreign languages of employees within financial and technology firms, how these tools strengthen professional identity and interpersonal communication, and how code-switching facilitated by AI impacts user experience and workplace engagement. Drawing from the …

In Flux, Gavin G. Gilmore

Electronic Theses and Dissertations

This thesis explores my practice of non-representational, mixed media painting as a way to consider the passage of time and the shifting nature of memory. Working in layers of paper, pigment, paint, and other materials, I build and disrupt surfaces that mirror the instability of short-term memory and the gradual erosion experienced during my father’s journey with Alzheimer’s disease. Each painting becomes a palimpsest where gestures accumulate, fade, or reemerge, reflecting how memories surface, distort, or disappear.

Through this layered process, the work intertwines personal narrative with broader questions of how time is felt rather than measured. The paintings act …

The Relationship Between Emotional Intelligence, School Culture, And School Leadership, Virginia Lorean Smith

Electronic Theses and Dissertations

Abstract

This study was a qualitative instrumental single holistic case study as outlined by Robert Stake in

1995. It focused on three research questions. The goal was to gain perspectives from teachers

and a principal on teacher retention and the culture of a campus. The emotional level of the

principal was evaluated on social awareness, self-awareness, relationship management, and self-

management by the principal taking part in an emotional intelligence assessment. The single

holistic case study approach was used, which had six phases of analyzing the data. The results

were then compared to the teachers’ interviews and surveys that were …

Hire And Hope: An Exploration Of Principal Turnover, Jessica D. True

Electronic Theses and Dissertations

This study is designed to investigate the possible relationships between principal turnover within K-12 public schools in the State of Texas, and demographic characteristics of school location, principal’s ethnicity, principal’s gender, and principal’s level of post-secondary degree. Data for participating schools was gathered from state-reported educator information specifically for the 2018/2019, 2019/2020, 2020/2021, 2021/2022, 2022/2023, and 2023/2024 school years. The longitudinal study reviewed K-12 non-charter public schools in Education Service Center (ESC) 11, which encompasses all public schools in the Fort Worth metroplex of North Texas, allowing this study to analyze a robust and inclusive dataset. The Chi-Square Test of …

Digital Leadership: Secondary Education Principals’ Perceptions And Change Competencies Toward Implementing Digital Citizenship Curricula, Waylon M. Randolph

Electronic Theses and Dissertations

Secondary education public schools are increasingly being confronted with student misuse of information and communication technologies (ICTs). Students are using these technologies to engage in disruptive and harmful behaviors like cyberbullying and sexting. As a result, some public school districts have responded by banning the use of ICTs in the classroom, while others have turned to teaching digital citizenship through a dedicated digital citizenship curriculum. However, effectively implementing such a curriculum remains a significant challenge. According to the literature, the best way to implement a digital citizenship curriculum is by fostering a positive school culture where stakeholders model and support …

Professor Perspectives: Inclusion Of Students With An Intellectual Disability In Transition Programming On A College Campus, Melissa Jane Massey

Electronic Theses and Dissertations

Students with intellectual disabilities (ID) are often unemployed or underemployed compared to students who do not have ID. Transition or postsecondary programming for students with ID has increased in recent years in response to the U.S. federal requirement for special education professionals to complete transition plans before students turn 16. The requirement for transition planning in Texas is age 14, and the ARD committee including the student and parent come together to develop goals for future planning. Transition plans include information on future employment, future independent living skills, and agency connections that students with ID may need to access to …

African American Female College Students’ Experiences At Predominately White Institutions, Sh'nita Louise Mitchell

Electronic Theses and Dissertations

African American women who attend predominantly White institutions (PWIs) have historically encountered systemic challenges that include racial isolation, microaggressions, a lack of cultural understanding, and insufficient institutional support. These barriers often impact their sense of belonging, academic persistence, and overall success. I aimed to explore the lived experiences of African American women who graduated from PWIs to understand how these women navigate institutional structures and sustain their academic journeys. I aimed to examine the unique challenges and supports experienced by African American women, and to identify factors that contribute to or hinder their persistence and success at their PWI. The …

Leading Employees Remotely In A Post-Covid-19 Era: A Phenomenology Study Of Remotely Working Employees, George M. Hardy Jr

Electronic Theses and Dissertations

The problem addressed in this study was that remote working employees felt disconnected from their organizations, leading to post-COVID-19 studies on phenomena such as quiet quitting and the great resignation. The purpose of this study was to investigate remotely working employees’ perspectives on connectedness to gain an understanding of commitment within their organization that ultimately leads to the decision to remain or leave. A qualitative phenomenology study was used with data collected from 12 remotely working participants across multiple industries and states. Data were transcribed, coded, and analyzed using a thematic approach with member-checking and triangulation to ensure credibility. Two …

Beyond Leadership Turnover: Examining The Relationship Between Principal Supervisor Coaching And Student Academic Performance, Margo L. Nottingham

Electronic Theses and Dissertations

Schools that maintain stable leadership report increased student achievement outcomes. The problem is that over 21% of U.S. principals leave their positions in the first year in high-poverty contexts. Principals leave their roles due to high job demands, inadequate support, and limited professional development, leading to decreased performance and poor school culture. The problem examined in this study was the lack of evidence on whether coaching principal supervisors contributed to improved student achievement outcomes. The study aimed to determine whether coaching principal supervisors through a regional service center was associated with higher student achievement in low-performing elementary and middle schools. …

"Are We Okay?": Exploring Departmental Leadership Behavior In Higher Education Organizational Crises, Melody Y. Zuniga

Electronic Theses and Dissertations

This qualitative study explored how faculty in higher education institutions experienced their department leaders during organizational crises. With academic department leaders often appointed with little training for the role’s administrative challenges, they can be underprepared when a crisis befalls their institutions. A qualitative narrative design allowed 10 social work faculty from nine Christian institutions across the United States to share their stories of navigating internal and external crises. Data collection occurred primarily through semistructured interviews, with questions allowing for narrative elements of time, place, and sociality to emerge. Through reflexive thematic analysis, findings revealed four themes in faculty’s experiences with …

Understanding Digital Communication Gaps With Hispanic Families In A Charter School In South Texas, Ruby Cabrera Aguilar

Electronic Theses and Dissertations

Now that access to technology is prevalent, digital communication in school districts and between schools and parents should be of high priority. Since schools do not emphasize digital communication policies and practices, a problem seen is a lack of communication across districts involving school staff, parents, and students. Determining school leaders’ roles in closing digital communication gaps through policies and procedures deserves further study because effective communication leads to awareness, involvement, relationship building, and student success. In this study, the knowledge gap theory and qualitative action research through reports and interviews assisted in understanding the perspectives of six school staff …

Advancing Medical Education With Lifestyle Medicine: A Comprehensive Program Evaluation Using The Kirkpatrick Framework, Shanna L. Mello

Electronic Theses and Dissertations

This dissertation examined how a U.S. national lifestyle medicine residency curriculum influenced resident learning and practice using a program evaluation paradigm with a convergent mixed methods design guided by Kirkpatrick’s four-level evaluation model. The problem addressed was the persistent gap between evidence for lifestyle interventions and the limited preparation residents receive to deliver lifestyle counseling in routine care. The purpose of the study was to evaluate changes in residents’ reactions, learning, and clinical behaviors and to identify early patient-level signals and the implementation conditions that enabled or constrained behavior change. Quantitative methods analyzed archived pre- and posttraining surveys from 148 …

Closing The Graduation Gap: Factors That Impact The Graduation And Enrollment Rates Of First Generation African American Male Students At Predominantly White Christian Universities, Byron C. Johnson Jr

Electronic Theses and Dissertations

First-generation African American male students encounter unique challenges on their journey through higher education. These challenges include inadequate academic preparation, limited family support, financial hardships, and difficulties in finding a sense of belonging. Additionally, factors such as race and religion present significant barriers that hinder their ability to persist in and graduate from colleges and universities without institutional support. Strategic initiatives, programs, and services that address the specific needs of these students are crucial for promoting their academic and social integration, ultimately influencing their success in higher education. This study focused on the experiences of successful first-generation African American students …

Underrepresentation Of African American Women Superintendents In The Public Schools Of Texas: Descriptions Of Their Lived Experiences, Shani R. Wyllie

Electronic Theses and Dissertations

The problem addressed through this study was the underrepresentation of African American women superintendents in the public-school districts of Texas, despite women making up a majority of the public-school workforce. The purpose of this transcendental phenomenological study was to describe the lived experiences of African American women superintendents regarding the support and barriers they encountered as they navigated their journeys to the position of public school district superintendent in Texas. The study was grounded in the Black feminist thought framework. Five semistructured interviews were conducted with currently serving African American women superintendents in Texas. The participants had been in the …

School Leaders’ Perceptions Of Restorative Practices On Student Behavior, Jennifer Mary Herold Fontenot

Electronic Theses and Dissertations

United States public schools turned to a zero-tolerance approach to school discipline with hopes of improving school safety and climate in the 1990s. Administrators dispensed consequences such as suspension and expulsion without considering the whole student, regardless of the student’s conditions, motivations, or background. Many schools today focus on punitive measures rather than a holistic approach that considers the root causes of behavior, such as socioeconomic factors, mental health issues, or the student’s home life. Such actions can lead to disproportionately harsh punishments for marginalized students, particularly those from low-income backgrounds or communities of color, exacerbating existing inequalities. Thus, the …