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The Universality Of Solubility Divergence Effects In Multicomponent Liquid Mixtures, Pauline R. Norris

Dissertations

Critical point effects have been observed in pure fluids, ferromagnets, substitutional alloys, and in binary liquid mixtures having a miscibility gap. That these systems are disparate, while the phenomena observed are similar, serves as the basis for the statement of the Principle of Critical Point Universality, which governs all critical behavior. The effect of the critical point on solute solubility is readily observed; the solubility diverges towards infinity in the critical region. One finds in the critical region that the slope (∂ln solubility/ ∂ (1/Temperature)) of a plot of ln solubility vs 1/Temperature diverges toward infinity if only one composition …

Development Of Aerospace Sliding Mode Control Toolbox : Relative Degree Approach With Resource Prospector Lander And Launch Vehicle Case Studies, Sai Susheel Praneeth Kode

Dissertations

Sliding mode control and observation techniques are widely used in aerospace applications, including aircraft, UAVs, launch vehicles, missile interceptors, and hypersonic missiles. This work is dedicated to developing a MATLAB based sliding mode controller design and simulation software toolbox that aims to support aerospace vehicle applications. An architecture of the proposed aerospace sliding mode control toolbox (SMC Aero) using the relative degree approach is developed. The created SMC Aero libraries include the design of first order sliding mode control (1-SMC), second order sliding mode control (2-SMC), higher order sliding mode (HOSM) control (either fixed gain or adaptive), as well as …

Adaptive Element Spacing Synthesis Technique In Phased Array Antennas, Tanzeela Mitha

Dissertations

Phased array antennas are widely used in a variety of military and civilian applications. For a given application, their radiation characteristics, such as the sidelobes, position of the nulls, and the main beam direction, need to be altered to enhance the array performance. To control these properties for a given requirement, the elements of phased array antennas need to be either properly excited or physically rearranged in different periodic and aperiodic configurations. However, once the position of the elements is fixed to control a single aspect of the generated pattern, it cannot simultaneously fulfill any other specification. To further alter …

Modeling A Power-Generating Pulsed Nuclear Magnetic Nozzle, Nathan Schilling

Dissertations

Pulsed nuclear (fusion, fission, and fission/fusion hybrid) propulsion systems provide the potential for 10,000 s specific impulse and specific powers of 1000 W of jet power per kg of propulsion system mass. This enables a new class of medium thrust, high specific impulse capability, resulting in 1/3 of the trip times and significantly higher payload mass fractions compared with chemical propulsion performing the same mission. One of the challenges for pulsed nuclear propulsion is the conversion of an isotropic explosion to directed thrust, another challenge is the generation of electrical power needed to run these systems. To meet both of …

Development Of An Explainability Scale To Evaluate Explainable Artificial Intelligence (Xai) Methods, Stephen Mccarthy

Dissertations

Explainable Artificial Intelligence (XAI) is an area of research that develops methods and techniques to make the results of artificial intelligence understood by humans. In recent years, there has been an increased demand for XAI methods to be developed due to model architectures getting more complicated and government regulations requiring transparency in machine learning models. With this increased demand has come an increased need for instruments to evaluate XAI methods. However, there are few, if none, valid and reliable instruments that take into account human opinion and cover all aspects of explainability. Therefore, this study developed an objective, human-centred questionnaire …

An Investigation Of The Relationship Between Subjective Mental Workload And Objective Indicators Of User Activity, Greg Byrne

Dissertations

Whilst the concept of physical workload is intuitively understood and readily applicable in system design, the same cannot be said of mental workload (MWL), despite its importance in our increasingly technological society. Despite its origin in the mid 20th century, the very concept of ”mental workload” is still a topic of debate in the literature, although it can be loosely defined as “the amount of mental work necessary for a person to complete a task” (Miller, 1956; Longo, 2014). Several methods have been utilized to measure of MWL, including physiological methods such as neuro-imagery, performance-based metrics, and subjective measures via …

Leadership Styles And Effective Leadership Among Higher Education Leaders In The North American Division Of Seventh-Day Adventists, Patrice A. Wright

Dissertations

Problem

Leadership has been shown to be crucial in the success of organizations, especially in higher education. However, little research has been done about leadership styles and effectiveness in North American Division (NAD) of Seventh-Day Adventists (SDA) higher education institutions. My study examined transformational, transactional, and passive avoidant leadership styles and leadership effectiveness in these higher education institutions.

Method

To examine leadership in Adventist colleges, I used the online MLQ-5X short form. I secured participation from 12 colleges and after repeated emails secured 168 responses. I analyzed the relationship between leadership styles, several leader characteristics and leader effectiveness, using SEM, …

"The Best Man That Ever Trod Shoe Leather" And His "Crown Of Rejoicing" : The Personal Relationship Of James And Ellen White, 1845-1881, Gerson Cardoso Rodrigues

Dissertations

James White (1821-1881) and Ellen G. White (1827-1915), co-founders (with Joseph Bates) of the Seventh-day Adventist denomination, were united in marriage on August 30, 1846, and lived together for thirty-five years until James died. As leaders (though Ellen White never assumed any administrative post) of the emerging denomination and putting all effort for the growth and mission of the Adventist cause, the Whites lived an intense life of writing, publishing, preaching, and traveling. Though their marriage was a blessing for both of them, the intensity of their lives, health issues, and their humanity, caused marital difficulties in some periods of …

Diversity, Equity, And Inclusion At Faith-Based Institutions: A Quantitative Study At Two Seventh-Day Adventist Institutions Of Higher Learning In North America, Erin Doggette

Dissertations

Problem

The need to address Diversity, Equity, and Inclusion at university campuses is critical. The campus climate impacts college students' overall collegial relationships and academic abilities. Since 1976, there has been an increase of 19.1% marginalized students enrolled in college. For these students, a sense of belonging is believed to aid in improved collegial relationships and better academic performance. According to the research, students who have positive perceptions of the campus climate tend to be more satisfied with their overall college experience and become more academically successful. Private, faith-based institutions must consider conducting campus climate surveys to assess potential diversity, …

Church Planting: Exploring The Actual Experiences And Stories Of Four Church Planters Of The Plant1000 Evangelism Initiative In The North American Division Of The Seventh-Day Adventist Church, Hyveth Williams

Dissertations

Problem. Plant1000 was launched in 2016 by the North American Division (NAD), the fifth largest of 13 divisions of the worldwide Seventh-day Adventist Church. Since then, it has been reported that over 1000 new church plants have been started, but we do not really understand how healthy most of these are, or not. We also do not know what they are actually experiencing in their developing into viable congregations. The focus of this dissertation is the story of four selected church plants that may be able to help us understand those dynamics that, at the moment, are little understood. -- …

A Study Of The Language Shifts In The Book Of Daniel : A Comparative Narrative Analysis Of Daniel 1 And 2, 7 And 8, Laura K. Morrow

Dissertations

Problem

The problem this dissertation seeks to address is the use of bilingualism in the book of Daniel. Previously, scholars have utilized diachronic methods to explain the phenomenon of bilingualism in Daniel and have concluded that it is the product of compositional redaction. However, such studies have not produced a consensus in scholarship. In the last 40 years, several studies have emerged that conclude the use of bilingualism in the book of Daniel may best be explained as a rhetorical device. In contrast to the diachronic methodologies of prior studies, these examinations utilized methodologies that addressed rhetorical elements. Chapter One …

An Investigation Of Mathematics Self-Efficacy, The Sources Of Mathematics Self-Efficacy, And Mathematics Achievement Among Primary School Students In Trinidad And Tobago, Ronald Sinanan

Dissertations

Purpose of the Study

This dissertation addressed two problems in the literature. Firstly, while many study findings have highlighted the critical role of self-efficacy in students' achievement, additional research was needed about the four hypothesized sources that influence the improvement of students' mathematics self-efficacy. Many studies on self-efficacy sources were conducted with measures not closely tied to social cognitive theory and have not demonstrated sufficient reliability. Using the Sources of Mathematics SelfEfficacy Scale, Usher and Pajares (2009) addressed this problem. They suggested several recommendations for future research (Usher & Pajares, 2008b, 2009), including exploring the validity of their scale in …

Racial Identity, Hair Esteem, Hair Texture, And Hairstyle Choice As Correlates Of Psychological Well-Being Among Afro-Latinas In The United States, Marielsy Esther Pimentel

Dissertations

Problem

During the Colonial period, hair was one of the designated phenotypic markers of racial group membership used to assign or deny privilege. Privileges are still assigned to people based on their racial group membership and their proximity to Whiteness. As such, Hair remains a salient part of Afro-Latina women’s lives and identities, with its influences seen in the personal, social, and mental realms. How an Afro-Latina wears her hair can have legal, social, and intrapersonal consequences. The subsequent treatment of Afro-Latinas because of their hairstyle can affect how they view themselves and even how they relate to others, especially …

Indicators Of Typology In The Narrative Of Elijah: An Investigation Into The Predictive Nature Of Biblical Theology, JôNatas De Mattos Leal

Dissertations

Elijah is among the most popular prophets in the Judeo-Christian tradition. In Judaism, the hope for his return has evolved into a plethora of legends in which he functions as a helper to the righteous in the present and avenger to the wicked in the future eschaton. In Christianity, the expectation involving his return has also a multitemporal dimension, but its fulfilment is typologically oriented. More often, scholars study the fulfilment of the Elijah typology from the NT perspective in a backward movement. This dissertation investigates this typology in a forward movement going from the OT to the NT while …

Strengthening Mission Through Strategy: An Analysis Of The Mission-Driven Excellence Strategy, Osvaldo Souza Santos Jr.

Dissertations

The Office of Strategy and Research (OSR) for the Seventh-day Adventist (SDA) churches in the North America Division (NAD) is beginning to implement a new strategy that focuses on mission. The OSR designed the strategy, created tools and materials to support the churches in implementing the Mission-driven Excellence (MdX) strategy. MdX combines planning and direction that helps church leaders to think strategically. MdX is a combination of pre-events, processes, and resources combined with local church strategies toward mission. The purpose of this study was to suggest strengths and improvements to the Mission-driven Excellence (MdX) strategy by seeking to better understand …

Childhood Obesity Interventions In The Republic Of Trinidad And Tobago: A Qualitative Study Exploring Government Policies And Their Implementation By Health Practitioners, Phyllis Woolford

Dissertations

Because of the rising prevalence of childhood obesity and overweight in the Republic of Trinidad and Tobago, and the observation that efforts to address the problem were showing disappointing results, this study seeks to explore the experiences and views of policymakers, health practitioners, and parents of overweight and obese children, in order to inform leaders and policy makers regarding the current interventions.

Method

A qualitative research case study methodology is the research design used, which, with my research questions, I considered would best uncover knowledge and provide perspectives that would provide an increased understanding of the issues arising from the …

Impact Of Parent Presence On Stress In Infants In The Neonatal Intensive Care Unit, Susan M. Horner

Dissertations

The purpose of this study was to examine potential relationships between cumulative stress exposure in infants in neonatal intensive care units (NICU), as measured using a resting salivary cortisol level at NICU discharge, and the amount (hours per week) or frequency (days per week) of parent presence and skin-to-skin care (SSC). This descriptive study was conducted via a secondary analysis of a dataset representing 78 NICU families from a tertiary level NICU in the Midwest. Median length of stay was 33 days, and a resting salivary cortisol level collected at one month of age was used for infants not discharged …

Selecting And Composing Cyberattack Component Models, Katia P. Maxwell

Dissertations

Modern society is increasingly reliant on computer systems for nearly all aspects of life, and the security of those systems has become an urgent concern. A research program that consists of several interconnected research projects in cybersecurity modeling has to date included the definition of a form of Petri nets extended with additional features specific to modeling cyberattacks, the automated generation of executable cyberattack component models from an attack pattern database, formal representation, and machine learning of attacker and defender strategies during cyberattacks, and the verification and validation of the component models. Because computer systems targeted in cyberattacks may have …

Constraining Intrinsic Properties Of Gamma-Ray Bursts From Core-Collapse Supernovae And Neutron Star Mergers, Rachel Hamburg

Dissertations

Gamma-ray bursts (GRBs) are ultra-relativistic jets produced by either the core-collapse of massive, stripped envelope stars (i.e., "collapsars") or the merging of compact binary objects, such as neutron stars. GRBs are among the most energetic transients in the Universe, yet despite over 5 decades of study, a full description of their intrinsic energetics remains incomplete. This is primarily due to a combination of cosmological, relativistic, and observational effects that have impeded obtaining GRB redshift measurements and robustly associating GRBs with their progenitors. In this dissertation, I study source-frame properties of GRBs from collapsars and binary neutron star (BNS) mergers. In …

An Investigation Of The Impact Of Canadian Wildfires On Us Air Quality Using Satellite, Model And Ground Measurements, Zhixin Xue

Dissertations

In recent years, frequent and widespread wildfires in Canada have become the “new normal” during summer, which degrades the U.S. air quality significantly. Smoke from wildfires in British Columbia and Alberta can be transported by northwesterly winds to the U.S. and cause health issues to vulnerable populations, which also increases the health costs to the country. During the fire season, daily PM2.5 in cities along the smoke transport path in the United States can increase 5 to 10 times compared to pre-fire values. This research examined different processes affecting smoke's vertical and horizontal transport and quantified the increase in fine …

Functionalized Nanomaterials As Tailored Theranostics, Kavini M. Rathnayake

Dissertations

Theranostic nanoparticles are a type of biodegradable and biocompatible multifunctional nanosystems in combination with diagnostic and therapeutic capabilities for more specific and personalized disease management. However, difficulties still exist in engineering biocompatible theranostic nanoparticles with highly specific to intracellular bacteria and tumor. Development of nanoassemblies which can overcome these difficulties to achieve maximum therapeutic efficacy of the drugs will be discussed in this dissertation. Pseudomonas aeruginosa (PA) is an opportunistic pathogen, which causes serious lung infections in immunocompromised patients. Traditional oral intake of large quantities of small-molecule antibiotics to treat bacterial infections leads to off-target toxicity and development of drug-resistant …

Basic Psychological Needs Satisfaction, Autonomy Support, And Mindsets As Predictors Of Self-Regulation In University Online Learners, Ting Jin

Dissertations

Problem

In contrast to more traditional learning environments, it can be difficult to "see and hear" both the instructor and, more crucially, the students when engaging in online education. This has been one of the most common criticisms leveled against online education for a long time. The COVID-19 disruption and transformation of online learning in higher education underlines the fact that variance among online learners in terms of academic success and psychological well-being are determined by the level and quality of self-regulation. What is the degree of self-regulation among American university students who study online because of the COVID-19 pandemic's …

The Case For Alternate Media Requirement Expressions In Systems Engineering, Jason Kolligs

Dissertations

“Requirements” are often presented as a necessary, if not mandated, component or tool of the systems engineering process. Despite their place in engineering, low quality requirements are the first potential mistakes of an engineering project and their effects are potentially felt downstream in the form of increased costs and schedule overruns. Innovations to improve requirements engineering have historically omitted the requirement media. This research provides the rationale and process heuristics to include alternate media requirement expressions within systems engineering which shifts accountability to higher context requirement expressions that may require less cognitive load while decreasing effort and schedule thereby potentially …

Climate Change Adaptation And Retrofit Planning For Coastal Residential Buildings Subjected To Hurricanes, Babak Salarieh

Dissertations

Hurricanes are considered one of the most destructive and costly events, posing a significant threat to coastal communities and infrastructures across the Atlantic and Gulf coasts of the U.S. This devastating phenomenon is an extreme weather event, and its intensity is known to be impacted by environmental parameters such as sea surface temperature. Due to the predicted increase in the sea surface temperature associated with climate change projected, the intensity of future hurricanes is expected to increase substantially. Additionally, the continued population growth of coastal regions and the accompanying increase in the number of residential buildings is increasing the potential …

Reuse Considerations For Successful Complex Systems Integration, Logan Grumbach

Dissertations

As systems have become increasingly complex, engineers are relying on reuse of components and subsystems as a method to curb complexity. However, integrating these reuse components and subsystems have historically often resulted in catastrophic failures. Technical principles key to integration success and the role of reuse in these principles are not currently defined. The objective of this research is to, first, derive and validate a set of technical integration principles and subsequently to explore how incorporating reuse impacts integration success. This research uses historical system integration data and a combination of qualitative analysis techniques and quantitative techniques to draw conclusions …

And Still, I Rise: Madre Poderosas In The Pursuit Of Work-Life Justice In Educational Leadership Roles, Janet Oseguera-Valencia

Dissertations

The purpose of this mixed-methods study was to: (1) to describe and understand Latina leaders' experiences, perceptions, and challenges work-family conflict cause from an institutional, cultural, and individual lens; (2) and understand Latina leaders experiences, perceptions and helpful solutions work-life justice may create from an institutional, cultural, and individual lens. This study used quantitative data from a survey, and qualitative data from interviews. There were a total of sixty-three Latina leaders that participated in the survey and eighteen interviewed. The conceptual framework for this study centered around (1) a history of work-family conflict in educational leadership; (2) the complexities of …

Communal Storywork: Deaf Education And The Latine Community, Noralee Jasso

Dissertations

In order to challenge the dominant and deficit perspectives in deaf education, this study utilized a Critical Race Theory framework to examine Latine families with Deaf children as they are portrayed in literature across areas of policy, research, and practice. Through qualitative semi-structured interviews, this research project invited nine adult Latine family members with Deaf children to share their lived experiences with having a Deaf child as part of the family and within a California school. To center the experiences of Latine families with Deaf children as visible, legitimate and necessary constituents of their children’s educational journeys, this research required …

An Unconventional Pathway: A Qualitative Inquiry Into The Experience Of Racial Minority Transfer Students, Hanh My Mai Tran

Dissertations

Transfer students’ success is increasingly being discussed in higher education. A large population of transfer students includes racial minority, low-income, and first-generation college students. Due to the multiple layers of students’ identities, it has been difficult for educational leaders in institutions to grasp the essential elements needed to serve these students. As a result, this qualitative study contributes to this discussion and efforts to support the transfer student’s success. In this study, qualitative methods, including interviews with 14 students from 4-year universities and community colleges and a survey, were used to identify the steps and resources associated with supporting transfer …

Culturally Responsive School Leadership In Continuation High Schools: An Alternative Approach In Leadership Styles, Roberto C. Portillo

Dissertations

Continuation high schools and the students they serve are often invisible and ignored to most Californians. However, state school authorities estimate that over 115,000 California high school students will pass through one of the state's 519 continuation high schools each year, to either graduate with a diploma, or to drop out of school altogether (Austin & Dixon, 2008). Principals in these schools must be exceptional and well prepared. However, principals have been trained to implement culturally responsive school leadership at their sites. Eight continuation high school principals described their experiences regarding their preparation, supports, challenges and successes in implementing culturally …

Isaac Newton As A Prophetic Interpreter, Kenneth Jørgensen

Dissertations

Throughout his life, Sir Isaac Newton was deeply dedicated to the science of decoding biblical apocalyptic writings. To understand and appreciate Newton's prophetic scheme, it will be advantagous to have a certain grasp of what sources and ideas might have influenced him. No comprehensive study before this one has helped us see Newton from that perspective. A survey of the development of canonical apocalyptic hermeneutic and interpretation, beginning before the time of Christ and ending with Newton, shows that four distinct systems of hermeneutics had developed by that time. Historicism was the earliest and the preferred system among Protestants until …