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Rocket Injector Flowfield Characterization Through Local, Instantaneous Gas Composition Tracing Using Laser Induced Breakdown Spectroscopy, Michaela Renee Hemming

Dissertations

Laser induced breakdown spectroscopy (LIBS) was developed for applications in the characterization of rocket engine injectors to evaluate the instantaneous, local gas concentration, or local mixture ratio of the injector flowfield. In this work, LIBS was tested in steady flows of premixed methane and air to create the correlation of the LIBS spectral species ratios H/O ratio, followed by a steady non-premixed flow to extract the localized mixing and shape of the flow field, then a transient study was performed to measure the development of the flow of the reactants in a pentad impingement injector previously used in RDE tests. …

The Impact Of Emotional Intelligence On The Leadership Of Elementary School Principals, Berteil Yousefi

Dissertations

Purpose: The purpose of this phenomenological study was to determine how the key emotional intelligence (EI) dimensions of self-awareness, self-regulation, social awareness, and relationship management impact the leadership effectiveness of exemplary elementary school principals in terms of decision making, interpersonal relationships, and overall school climate.Methodology: Thirteen elementary school principals from Stanislaus County, Northern California, with at least 3 years of experience participated in semi-structured interviews. Data were transcribed and analyzed using Moustakas’s (1994) transcendental phenomenological approach, facilitated by NVivo 15 software. Trustworthiness was ensured through member checking, peer debriefing, and interrater reliability (80%).

Findings: Seven major themes emerged. First, self-awareness …

How Exemplary Elementary School Principals Embed The Infinite Mindset Practice To Inspire The Achievement Of Extraordinary Results, Amna Osman

Dissertations

Purpose: This phenomenological study explored how exemplary elementary school principals perceive and embed Sinek’s (2019) infinite mindset framework within their organizations to achieve extraordinary results. A secondary purpose was to examine how perceived organizational supports and barriers influence the development of an infinite mindset among these principals.Methodology: This phenomenological study examined the lived experiences of exemplary elementary school principals and their perspectives on implementing the five Infinite Mindset practices in their schools. The study focused on public elementary school principals in Monterey County, California. From 49 principals across six districts, 10 were purposefully selected based on established criteria for exemplary …

Integrating Military-Acquired Iso Quality Management Principles Into Civilian Employment: A Phenomenological Study Of Post-9/11 Veterans, Paul Encinias

Dissertations

Purpose: This qualitative phenomenological study explored how post-9/11 U.S. military veterans describe their lived experiences of understanding and applying four ISO 9001:2015 Quality Management Principles (leadership, engagement of people, process approach, and evidence-based decision making) during the transition to civilian employment. This study further sought to understand how veterans articulated these competencies across employment stages and how those competencies were recognized within civilian organizations.

Methodology: This qualitative phenomenological study used semistructured interviews with 10 post-9/11 U.S. military veterans residing in the United States who had separated from active duty and were engaged in the transition to civilian employment. Participants were …

From Glass Ceilings To Balustrades: The Barriers And Supports In Gender-Balanced Corporate Boards Through The Lens Of Activity Theory, Erica Joy Thompson Dias

Dissertations

Purpose: The purpose of this qualitative study was to examine, through the lens of activity theory (AT), barriers individuals on public company boards of directors experienced in achieving or maintaining gender balance and supports that mitigated those barriers.

Methodology: Data were collected through semistructured interviews with 16 directors representing 13 gender-balanced public company boards. Data were coded using the AT framework, which conceptualizes human activity through interacting components including subject, object, rules, tools, community, and division of labor. In this study, barriers were tensions that obstructed progress toward gender balance, and supports were methods, resources, or actions that mitigated those …

Student Perceptions Of Academic Support Systems: A Sequential Mixed Methods Analysis Of Persistence, James Anderson

Dissertations

Purpose: The purpose of this sequential explanatory mixed-methods study was to assess the perceived influence of first-year institutional support services on student retention from the first to the second year at regional public universities in the Northeastern United States.

Methodology: A sequential explanatory mixed-methods design was used. In the quantitative phase, 437 retained second-year students completed the researcher-designed Retention Support Impact Survey to assess service utilization and perceived effectiveness. In the qualitative phase, 10 students participated in semi-structured interviews to provide deeper contextual insight into the numerical data.

Findings: The data indicated a disparity between service utilization rates and student-reported …

Exploring Exemplary Leadership: A Phenomenological Study Of Campus Presidents, Krysten Stone

Dissertations

Purpose: The purpose of this phenomenological study was to identify and describe the strategies used by exemplary campus presidents to build and lead resilient teams in for-profit vocational colleges, grounded in Kirkman and Stoverink’s (2023) team resources framework.

Methodology: This phenomenological study explored the lived experiences of 10 exemplary campus presidents serving in for-profit vocational colleges throughout California’s Central Valley. Purposeful sampling was used to identify participants who met the study’s criteria. Data were collected through semistructured, open-ended interviews and the analysis of four organizational artifacts including strategic plans, communication workflows, meeting structures, and leadership models. Data were systematically coded …

Elementary General Education Teachers' (Tk–1) Experiences Implementing Inclusive Practices For Students With Disabilities, Emily Ruth Engelson

Dissertations

Purpose: The purpose of this qualitative multi-case study was to examine the challenges elementary general education teachers (TK–6) face, including confidence and skills, when working to successfully include students with disabilities in their classrooms. The study also sought to identify the most valuable professional development experiences, the role of grade-level collaboration in building teachers' capacity, and the administrative support and resources that contribute to teachers' success in including students with disabilities.

Methodology: This qualitative multi-case study employed semi-structured interviews with six TK–first grade general education teachers in Orange County, California, each with at least one year of experience including a …

Walking On A Tightrope: Women And Managers Navigating Maternity Leave And Return-To-Work, Rachel R. Kalvert

Dissertations

Purpose: This qualitative phenomenological study explored how professional women experience maternity leave and return-to-work, focusing on how managerial communication shapes perceptions of career, competence, belonging, and career progression. The study involved professional women who returned to the same organization full-time from 6 months to 3 years after maternity leave.Methodology: Fourteen professional women were recruited via snowball sampling and listservs. Data were collected through Zoom interviews. Participants completed a demographic questionnaire and received interview questions in advance. The interview guide aligned with the study's three questions. After the interview, participants reviewed AI-generated transcript summaries for accuracy; and participants were given a …

Teachers’ Perceptions Of Principals’ Transformational Leadership And Its Impact On Job Satisfaction In Rural California, Pesach Walter

Dissertations

Purpose: This phenomenological study explored how early-career teachers in rural California public schools perceive their principals’ transformational leadership behaviors and how those perceptions influence job satisfaction, retention, and leadership effectiveness.

Methodology: A qualitative phenomenological design examined the lived experiences of early-career teachers in rural California K–12 public schools. Five participants with three to five years of experience were selected by purposive sampling; rurality was defined by National Center for Education Statistics locale codes 41, 42, and 43. Data were gathered through semi-structured, 60-minute Zoom interviews guided by a researcher-developed protocol based on Bass’s Four I’s framework. Transcripts were coded in …

An Explanatory Mixed-Methods Study Identifying And Describing The Perceived Impact Of Five Disruptive Career Skills On Women’S Career Advancement To An Executive Leadership, Roque Ramirez

Dissertations

Purpose: The purpose of this explanatory mixed-methods study was to identify and describe the perceived impact of Johnson and Mohr’s (2019) five disruptive career skills on the career advancement of female chief petty officers with a military background as they progressed into a leadership position.Methodology: This explanatory mixed-methods study examined the experienced of eight female chief petty officers regarding the use of personal disruption strategies. Participants were selected through purposive sampling based on predetermined eligibility criteria and recommendations. Data were collected and analyzed by calculating means scores for quantitative responses and identifying qualitative themes related to the five personal disruption …

Practices Alternative Education Principals Use To Create An Infinite Mindset In Their Schools To Inspire Extraordinary Results, Renee Gates

Dissertations

Purpose: The purpose of this phenomenological study was to explore and describe how exemplary alternative education principals perceive the practices of Simon Sinek’s Infinite Mindset Framework are embedded within their organizations to inspire the achievement of extraordinary results. A further purpose of this study was to understand the organizational supports and barriers these exemplary leaders perceive affect the development of an infinite mindset.

Methodology: Interviews were used to explore and describe how exemplary alternative high school principals perceive the five practices of Sinek’s Infinite Mindset are embedded within their organizations. The study is intended to contribute to and extend current …

Influence Of The Solar Cycle And Interplanetary Shocks On Turbulence At 1 Au, Sujan Prasad Gautam

Dissertations

This thesis studies the effect of the solar cycle and interplanetary shocks on turbulent fluctuations at 1 AU. We examine the solar cycle dependence of turbulence cascade rates corresponding to the total turbulence energy using the methodology developed by Adhikari et al. that utilizes a Kolmogorov phenomenology. Turbulence cascade rates are derived using 25 years (1995–2020) of Wind spacecraft plasma and magnetic-field observations. We find that the total turbulence energy cascade rate changes with the solar cycle, such that the cascade rate is largest during solar maximum and smallest during solar minimum. It is positively correlated with the solar wind …

Pediatric Clinical Reasoning Labs’ Impact On Student Self-Efficacy In Pediatric Physical Therapy Education, Bethany Early

Dissertations

All graduates of entry-level Doctor of Physical Therapy (DPT) programs must be competent to work with patients across the lifespan and high levels of perceived self-efficacy (SE) may be a predictor of future success. Experiential learning is an effective teaching and learning strategy used within Pediatric PT education (PedPTE). This study examined the extent to which pediatric clinical reasoning labs impact student SE within PedPTE, and to what extent does previous experience or interest in pediatrics have on perceived SE.

The methodology was a sequential explanatory mixed methods research design. Quantitative data collection included 27 second year DPT students, utilizing …

Grit And Inclusive Practice: A Phenomenological Study Of General Education Teachers In A Title I Elementary School, Andrea Martinez

Dissertations

Purpose: The purpose of this qualitative phenomenological study was to describe elementary general education teachers' perceptions of how the core principles of grit, as defined by Duckworth et al. (2007); passion, perseverance, resilience, goal commitment, and growth mindset, influence their ability to implement inclusive practices for students with disabilities in general education classrooms.

Methodology: A qualitative phenomenological design was used to explore the lived experiences of elementary general education teachers. Purposeful sampling was used to identify participants who met the study criteria. Eight elementary general education teachers employed at a Title I public elementary school in Kings County, California, participated …

A Delphi Study: Communication Practices For Expert Elementary Administrators During Day-To-Day Crises On Elementary School Campuses, Anthony Michael Langford

Dissertations

Purpose: The purpose of this Delphi study was to identify the communication practices expert elementary school administrators consider the most effective for informing their district office, staff, students, parents, and the community during day-to-day crises. The study also evaluated the effectiveness of these identified practices and determined the best methods for implementing the top three practices in each area. Methodology: This Delphi study focused on three areas of research: (a) the practices expert elementary administrators use to communicate during day-to-day crises, (b) the way expert elementary administrators rate the effectiveness of those practices, and (c) the methods expert elementary administrators …

The Art Of Crisis Leadership By Exemplary Naval Frontline Leaders, Broadus Brooks

Dissertations

Purpose: This qualitative, multiple-case study held significant importance because it aimed to identify and describe the strategies used by exemplary naval frontline leaders to lead in crisis, particularly during the COVID-19 pandemic. The study focused on the five critical tasks of strategic crisis leadership (sensemaking, decision making/coordination, meaning making, accounting, and learning), providing a unique insight into the experiences of these leaders during a crisis.Methodology: This qualitative, multiple-case study employed interviews to collect data from exemplary naval frontline leaders to identify and describe their leadership strategies during the unprecedented COVID-19 global health crisis.

Findings: Crisis leadership among U.S. naval frontline …

The Adolescent Development Of Small Business Owners’ Entrepreneurial Mindset, Fern Arredondo

Dissertations

Purpose: The purpose of this phenomenological study was to describe how small business owners in Southern California interpret experiences before age 20 that influenced the development of the eight domains of the Network for Teaching Entrepreneurship (NFTE) Entrepreneurial Mindset Index (EMI). This study used a qualitative phenomenological approach to explore how adult small business owners reflect upon and interpret experiences before age 20 that influenced the development of their entrepreneurial mindset. By examining the influence of pre-adulthood on these owners, the study aimed to deepen the understanding of how early experiences shape entrepreneurial mindsets and contribute to long-term entrepreneurial success. …

The Impact Of Vulnerability On Building Trust: A Qualitative Study Of Superintendents In Northern California, Jasmin Hasmukhlal Patel

Dissertations

Purpose: The purpose of this phenomenological study was to understand and explain how exemplary superintendents in Northern California practice vulnerability to build trust within their organizations, guided by Brené Brown’s framework of vulnerability-based leadership: Authenticity, courage over comfort, curiosity and learning, practicing empathy, and leading with heart. An additional purpose was to examine the challenges these leaders encounter when practicing vulnerability in complex public education contexts. This study addresses a gap in leadership research by providing empirical insight into how vulnerability functions as a trust-building practice at the highest level of K–12 educational leadership.

Methodology: A qualitative phenomenological design was …

Rewriting The Future: Examining The Influence Of Mentoring On Ged Graduates' Pursuit And Performance In Postsecondary Education, Shari Antoinette Crain

Dissertations

This phenomenological study explored the lived experiences of GED graduates who were mentored while earning their GED and examined how those mentoring experiences contributed to their academic achievement in community college. Although increasing numbers of adult learners pursue postsecondary education through the GED pathway, many encounter barriers related to academic confidence, institutional navigation, and access to support systems. Limited research has examined how mentoring supports GED graduates during their transition into higher education.

Guided by the College Student Mentoring Scale developed by Nora and Crisp (2009), this study examined mentoring experiences across four domains: psychological and emotional support, degree and …

Principal Leader Behaviors That Create Meaning For Their Teachers To Reduce Stress And Burnout, Angelina Santana

Dissertations

Purpose: The purpose of this mixed methods study was to identify and describe the behaviors that exemplary high school principals use to create meaning for themselves and their teacher followers through relationships, character, vision, wisdom, and inspiration. In addition, the study aimed to determine the new teachers’ perceived degree of importance of the principal leader behaviors related to relationships, character, vision, wisdom, and inspiration to help create meaning.Methodology: The mixed methods convergent study design uses qualitative and quantitative means to collect and analyze data to understand how exemplary high school principals make meaning for their teacher followers. First, qualitative interviews …

Meeting Battery Electric Vehicle Demand With A Focus On Throughput Capacity Across The Transport Nodes In The Upstream Cobalt Supply Chain, Nicholas J. Visconti

Dissertations

This study assesses whether cobalt transport capacity in sub-Saharan Africa is sufficient to support projected battery electric vehicle (BEV) demand under the Paris Accord. Using open-source data from ArcGIS, the Highway Capacity Manual, and the World Bank, the analysis applies a simplified linear programming approach to estimate the maximum throughput of the primary transport corridor connecting the Democratic Republic of the Congo to the Port of Durban. The model identifies significant constraints along the Rutenga-to-Beitbridge segment, reducing network capacity to an estimated 42,494 tons of ore per day. When converted to refined cobalt, this capacity falls well short of the …

Math Anxiety, Math Self-Concept And Math Self-Efficacy: A Study Of The Jingle-Jangle Fallacies, Marsha Natasha Durrant-Walker

Dissertations

Problem

The overlap and lack of clear distinction among the constructs of math anxiety, math self-concept, and math self-efficacy presents issues for research and practice. The literature reveals that math anxiety is closely linked to math self-concept (Klee et al., 2022). Additionally, math self-concept and math self-efficacy often overlap and are not easily distinguishable (Kranzler & Pajares, 1997; Pajares & Miller, 1994; Pajares & Urdan, 1996). Each of these constructs has been shown to play a critical role in student math achievement (Timmerman et al., 2016). -- When constructs are not defined or measured distinctly, inconsistencies may emerge in research …

Exploring Lessons In Research: A Survey On Parental Perceptions Of Reading Opportunities, Laura Kettlehut

Dissertations

Problem

This exploratory study examines how parents’ past reading experiences relate to their perceptions of their children’s current reading opportunities across home and school contexts. Grounded in longstanding literacy research, the study explores how parent‑led, educator‑led, and child‑initiated reading experiences collectively shape children’s literacy development.

Method

Two research questions guided the inquiry: (1) How do parents perceive their own past reading opportunities? and (2) How do they perceive their children’s reading opportunities at home and in school? To address these questions, a 41‑item survey was developed and administered to parents of children enrolled in K–8 schools. The instrument measured two …

A Qualitative Multiple Case Study Exploring Shifts In Thinking Of Principals Through Initiatives To Foster Relational Leadership Conducive To Retaining Teachers In High-Minority, High-Poverty Public Schools, Rita Seay

Dissertations

Problem

The public education system is broken, and teacher shortages have reached a crisis, especially in some specialty fields in United States (Carrillo & Salhotra, 2022; Podolsky et al., 2016). Lately, the teacher workforce has been described as a “leaky bucket” (Podolsky et al., 2016, p. 1). Indeed, the problems are complex in poor socioeconomic communities with racial and ethnic groups of students because teachers struggle to make a difference and, in most cases, fail due to insurmountable situations that are beyond their scope of influence (Rondfeldt et al., 2013). Evidence published that students suffer immensely from a broken, segregated …

Called To Lead: Leadership Journeys And Workplace Experiences Of Women Presidents In Seventh-Day Adventist Institutions, Gary Thurber

Dissertations

Problem

Although women constitute more than half of Seventh-day Adventist Church membership, they remain substantially underrepresented in senior leadership roles across North America. This disparity raises important questions about the historical, theological, organizational, and gender-related factors that shape women’s access to institutional leadership within the denomination. A growing body of scholarship has examined the life experiences of women clergy in the church; however, limited research has explored the experiences of women serving in presidential leadership roles within Seventh-day Adventist institutions.

Purpose

The purpose of this study was to understand and describe the experiences of women serving in presidential leadership roles …

A Ministry Manual For Supporting Pastoral Transitions: Addressing The Emotional And Spiritual Needs Of Clergy And Their Families, John Tucker

Dissertations

Pastoral transitions represent spiritually significant yet often under-supported moments in the life of clergy, congregations, and ministry networks. While leadership change is frequently framed in theological language emphasizing divine calling and institutional continuity, insufficient attention is given to the emotional, relational, and familial dimensions of these transitions. This Doctor of Ministry project examines the spiritual and emotional impact of pastoral transitions within African American church contexts, with particular attention to clergy wellbeing and systems of care.

This study employed a mixed-methods research design integrating quantitative survey data with qualitative semi-structured interviews. Survey instruments were distributed to pastors affiliated with The …

Generative Ai Professional Development Program For Higher Education Instructors, Sheena Bahra

Dissertations

As technology progresses and brings enhanced forms of artificial intelligence (AI), such as generative AI (Gen AI), it continues to affect education by introducing opportunities and challenges in its application to higher education teaching. Advances in technology can make instructors reluctant to use applications, leading to missed learning and skill-development opportunities for higher-order thinking skills. This study investigates how AI professional development (PD) training can influence higher education instructors’ willingness to use Gen AI in the classroom. This study employed a qualitative instrumental case study design informed by an exploratory lens. The study investigated instructors’ use of Gen AI in …

Delphi Study To Explore The Organizational Characteristics, Conditions, And Infrastructures Needed To Integrate Professional Development With A Career Advancement Framework In The Form Of Career Lattice, Shelly Yu-Tze Tze Shelly Wang

Dissertations

Purpose: The purpose of this policy Delphi study was to identify, prioritize, and build expert consensus on the organizational characteristics, conditions, and infrastructures that support employee access to professional development (PD) opportunities embedded within a career advancement (CAd) framework. Specifically, this study aimed to: (a) identify key organizational components necessary to support professional development within a career lattice structure, (b) determine the relative importance of these components as rated by experts, and (c) establish expert-recommended strategies for implementation.

Methodology: This study used a Delphi method, consisting of three rounds, to collect data from experts with the titles of manager, directors, …

Retention Of Elementary Special Education Teachers: A Phenomenological Study Of Retention Factors And Work-Life Balance In Brick-And-Mortar And Virtual, Independent Study Educational Environments, Meredith Clark-Lewis

Dissertations

Purpose: This phenomenological study aimed to identify the factors that influence the retention of elementary special education teachers in virtual, independent study environments and brick-and-mortar environments, and to explore similarities and differences in how elementary special education teachers experience work-life balance across educational settings.

Methodology: Purposeful sampling was used to identify 10 elementary special education teachers in California who worked in brick-and-mortar and virtual independent study settings and met the study's inclusion criteria. Semi-structured, open-ended interviews were conducted virtually, recorded, transcribed, and analyzed using NVivo qualitative data analysis software. Both deductive and inductive coding strategies were employed, guided by the …