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Machine Learning-Based Data Analytics For Understanding Space Weather And Climate, Yasser Abduallah

Dissertations

This dissertation addresses multiple crucial problems in space weather and climate, presenting new machine learning-based data analytics algorithms and models for tackling the problems.

First, the dissertation presents two new approaches to predicting solar flares. One approach, called DeepSun, predicts solar flares by utilizing a machine-learning-as-a-service (MLaaS) platform. The DeepSun system provides a friendly interface for Web users and an application programming interface (API) for remote programming users. It adopts an ensemble learning method that employs several machine learning algorithms to perform multiclass flare prediction. The other approach, named SolarFlareNet, forecasts the occurrence of solar flares within the next 24 …

Bioremediation Of Petroleum Hydrocarbons In Coastal Sediments, Charbel Abou Khalil

Dissertations

The biodegradation of dispersed crude oil in the ocean is relatively rapid (a half-life of a few weeks). However, it is often much slower on shorelines, usually attributed to low moisture content, nutrient limitation, and higher oil concentrations in beaches than in dispersed plumes. Another factor may be the increased salinity of the upper intertidal and supratidal zones since these parts of the beach are potentially subject to prolonged evaporation and only intermittent inundation. Therefore, two laboratory experiments are conducted to investigate whether such an increase in porewater salinity results in additional inhibitory effects on oil biodegradation in seashores.

In …

Combustion Soot Nanoparticles: Mechanism Of Restructuring And Mechanical Properties, Ali Hasani

Dissertations

Soot, a product of incomplete combustion of fossil fuels, is a global warming agent. The effect of soot particles on climate depends on their morphology. Freshly released soot particles are fractal lacey aggregates, but they often appear collapsed in atmospheric samples collected away from emission sources. A body of work has concluded that the collapse is caused by liquid shells when they form by vapor condensation around soot aggregates. However, some recent studies argue that soot remains fractal even when engulfed by the shells, collapsing only when the shells evaporate. To reconcile this disagreement, the effects of the condensation and …

Monitoring Climate Change With Machine Learning And Uncertainty Quantification, Firas Gerges

Dissertations

The impact of climate change on the environment has become increasingly visible today. One important topic in climate change monitoring is to forecast future climate events, which relies on long-term prediction of climate variables at a local regional scale. This topic is crucial for disaster risk management and for resolving climate change at the local level. General Circulation Models (GCMs) allow for the simulation of several climate variables, decades into the future. GCM simulations, however, are at a global large scale and are too coarse to monitor climate change at the local small scale. This dissertation explores new machine learning …

Amphiphilic Block Copolymers And The Applications In Therapeutics Delivery, Jie Dou

Dissertations

Well-defined thermo-responsive triblock copolymers containing polyethylene oxide (PEO) and poly(N-isopropyl acrylamide) PNIPAM are synthesized by a type of living controlled polymerization, named iniferter polymerization. The polymers are amphiphilic in nature and are self-assembled into a micelle. Their properties and application are characterized and investigated in this work.

Foremost, the initiator of the polymerization (iniferter) is designed and synthesized by condensation polymerization, where PEO is incorporated into the structure to improve biocompatibility, which has great potential for biological application. Moreover, this iniferter reagent could be applied to more than 70 percent of vinyl monomers.

NIPAM, a commercial vinyl monomer, is chosen …

Biotransformation And Biodefluorination Of Fluorotelomer Carboxylic Acids, Chen Wu

Dissertations

Per- and polyfluoroalkyl substances (PFASs), a class of emerging contaminants of concern, have attacked unprecedented attention given their prevalent detection and adverse health effects. Primary regulatory attention has been focused on PFOA, PFOS, and other perfluoroalkyl acids (PFAAs). Recent investigations revealed that fluorotelomer carboxylic acid (FTCAs), particularly 5:3 FTCA and 6:2 FTCA, were dominant in landfill leachates and other environmental matrixes. FTCAs are also found as common intermediates during the biotransformation of PFAA precursors. Unfortunately, FTCAs have higher bioaccumulating potential and are at least two orders more toxic than their corresponding PFCAs. However, information regarding the potentials and mechanisms of …

Water Management And Corrosion Performance From Protective Polymer Coatings With Spatially Controlled Hydrophilic Domains, Jessica M. Davison

Dissertations

Metallic corrosion has become an annual multibillion-dollar problem for the industrialized world and global contamination issue through the process of repair, removing, and reapplying protective coatings. Typical corrosion resistant coatings are comprised of polymeric coating layers with anti-corrosive pigments, plasticizers, sacrificial additives, and/or other formulation materials, which are formulated to prevent, detect, and manage corrosion. Our counterintuitive approach was to improve upon the understanding of how, when, where, and why environmental contaminants (reactants, mainly water and electrolytes) driving corrosion, propagate and accumulate as localized hydrophilicity shifts within a model polymer coated substrate. Herein, hydrogel particles (HGP) were synthesized of defines …

Barriers To Implementing A Work-Based Learning Program: A Health Science Educator Perspective, Daniel Harrison

Dissertations

Career and Technical Education programs’ mission statement is to supply a skilled workforce for all industries (ACTE, 2021). The Health Science pathway lags behind other industry sectors in active work-based learning programs (Greenfield & Stevens, 2018). Therefore, this study examines the potential barriers to implementing work-based learning programs within the Health Science pathway. The qualitative descriptive investigation into the three types of work-based learning of visits to the workplace, work-like experiences, and employment discovered critical findings regarding healthcare requirements, scheduling conflicts, and access to facilities. Finding 1 details healthcare requirements as the most significant barrier to work-based learning programs. The …

The Impact Of A Five-Day Number Sense Intervention On High School Student's Quantitative Reasoning Skills And Self-Efficacy, Rebecca Steele-Mackey

Dissertations

Understanding numerical quantities and applying this knowledge in practical applications is essential throughout life. A well-developed number sense comes from learning foundational skills and continuing to rely on these skills and concepts in higher mathematical education as well as in adulthood. Prior research shows that K-8 students lack a conceptual understanding of fraction, decimal, and percentage concepts (NCTM, 2009). While there is literature that identifies a deficit in these mathematical areas, there is a need to examine possible activities and interventions that can be performed throughout secondary education courses that support growth in students' conceptual understanding of rational number concepts. …

An Asset Model: Identifying Institutional Characteristics And Behaviors That Close Community College Completion Gaps Between Black And White Students, Courtney Lange

Dissertations

The United States fails to meet its own workforce needs, and estimates show that by the year 2025, almost two out of three jobs in the nation will require at least some postsecondary education or training (Carnevale et al., 2019b). Jobs with the fastest growth rate will require an associate degree (Carnevale et al., 2019b). According to the most recent national data from the National Student Clearinghouse (NSC) Research Center, one in three students begin their college journey at a community college (NCES, 2019). Only 40% finish a degree or credential within six years (NCES, 2019). The proportion of those …

Classroom Climate, Culture, Parenting Skills, And Student Grit, Karen Ochoa

Dissertations

The education system has noted that student motivation and perseverance are lacking, yet the focus on standardized testing over the last decade has increased the rigor and expectations in the classroom. As such, educational researchers are always looking for new and inventive ways to enhance student achievement without increasing the financial burden on the schools. Grit is the non-cognitive skill that a person processes that enable them to work hard, endure, and persevere through challenging times. A person who exhibits grit often succeeds over those who have the cognitive ability but do not have grit. Children in countries with collectivist …

A Look At The Effectiveness Of High School Chemistry Curriculum In Preparing Students For Act, Shanna Nesser

Dissertations

In the ever-changing world, students are challenged with cultivating the skills and knowledge needed to handle the pace and level of understanding required to excel in their future. The foundation for a student's future begins in their formative years, but high school is a prime environment for nurturing the applied, critical thinking, and problem-solving skills needed to move forward into independent, adult life. Mississippi schools are ranked by an accountability score, which is used to determine fund allocation and the development of improvement plans. This score is compiled by looking at various state-tested courses, College and Career Readiness Standards (MS …

A Framework For Assessing The 4th Rank Dispersivity Tensor Under Anisotropic Axial Symmetries, Xiang Fan

Dissertations

Multi-dimensional expansion of the advection-dispersion equation necessitated the representation of dispersivity as a 4th rank tensor. This tensorial form of dispersivity has 81 terms in three-dimensions with a maximum of 36 independent terms that may be used to describe Fickian spreading of a dissolved contaminant plume according to intrinsic properties of a porous medium. The complexity of the 4th rank tensor has led to the common practice of simplifying the tensor to only 2 or 3 independent terms by assuming isotropic conditions, although isotropic porous media are uncommon in nature as many natural geologic systems exhibit pronounced anisotropy. A broad …

A Qualitative Approach To Understanding The Career Perceptions And Choices Of Stem Undergraduate And Graduate Students, Jennifer M. Ribble

Dissertations

In order to remain competitive in the global economy, there has been a call to increase recruitment and retention in science, technology, engineering, and mathematics (STEM) careers in the United States (National Science Board, 2014, 2016; President's Council of Advisors on Science and Technology, 2012). In addition to increasing the number of individuals in these fields, it is also imperative to increase the diversity of the individuals filling STEM positions. Not only is it a moral responsibility to create STEM environments that are more inclusive of those who have been historically marginalized in STEM settings, but it is critical in …

Factors That Influence High School Students' Postsecondary Career Decisions In A Guaranteed-Tuition Based School District, Tracy Y. Miller

Dissertations

This study explored factors that influence the postsecondary career decisions of 427 11th and 12th grade students in a guaranteed tuition-based school district in a Midwestern state. Since 2005, this district has had a “Promise” program where eligible students can get up to 100% of their postsecondary tuition paid to attend a college, university, technical, or skilled trade program, or participate in an apprenticeship. Students have up to 10 years after graduating high school to utilize the funding. In addition, students who decide to enter the military after high school have up to 10 years to utilize the funding after …

Algebraic Reasoning And Conceptual Understanding: A Mixed Methods Comparison Of In-Person And Virtual Classroom Strategies, Erneice J. Jackson

Dissertations

Algebraic reasoning is the beginning school of thought to critical thinking. Employers are looking for this 21st century skill. The purpose of this research was to investigate equity in mathematics education using the NCTM Teaching and Learnings Beliefs Survey. Four area were studied: the number of years in education, the degree earned, the grade level taught in education, and the number of years in an educator’s teaching position. A mixed methods inventory was used. Most results were not rejected in this study. Two statements in the survey warranted a discussion. Recommendations were made for further research.

Development Of Geoscience Interest And Identity Of Female First-Generation Undergraduate Geoscience Students, Dina London

Dissertations

The purpose of this basic qualitative study was to understand how female first-generation undergraduate geoscience students developed their situational geoscience interests into individual interests that, in turn, supported their geoscience identity and decision to become a geoscience major. The experiences of six female first-generation undergraduate geoscience students were used to explore how geoscience interests and geoscience identities developed over time. I analyzed three artifacts representing participants’ geoscience identity, geoscience interest development timeline, and transcribed interviews to explore emerging themes relating to interest and identity development. Participants described events relating to their situational geoscience interests, individual geoscience interests, and the formation …

What We Say Matters: Exploring The Importance Of Microaggression Language For Lgbtq+ Science Major Undergraduate Students, Madison L. Fitzgerald-Russell

Dissertations

The purpose of this exploratory qualitative study is to better understand the climate for LGBTQ+ science major undergraduates in their departments through a transformative queer theory lens and intersectionality. Prior research on campus and STEM department climates have demonstrated inclusion issues continue to persist for LGBTQ+ individuals in higher education. One of these issues is discrimination in the form of microaggressions. Microaggressions against LGBTQ+ individuals have been demonstrated to cause physical, mental, and academic harm. In the literature, there is limited information on how microaggressions impact students in particular STEM fields.

LGBTQ+ science undergraduates from public colleges and universities in …

Remote Sensing Application For Landslide Detection: Monitoring Along Eastern Lake Michigan (Miami Park, Mi), Guzalay Sataer

Dissertations

I assessed the nature and spatial and temporal patterns of deformation over the Miami Park bluffs on the eastern margin of Lake Michigan and investigated the factors controlling its observed deformation. Our approach involved the following steps: (1) extracting bluff deformation rates (velocities along the line of sight of the satellite) using a stack of Sentinel-1A radar imagery in ascending acquisition geometry acquired between 2017 and 2021 and applying the Intermittent Small Baseline Subset (ISBAS) InSAR time series analysis method; (2) generating high-resolution (5 cm) elevation models and orthophotos from temporal unmanned aerial vehicle (UAV) surveys acquired in 2017, 2019, …

An Elementary School Principal’S Practices And A Reduced Equity Gap: A Case Study, April Hrovat

Dissertations

During the last 60 years, national standardized testing has confirmed a gap in reading and math scores between White and Black students, often called the achievement, opportunity, equity, or race-based gap (Coleman et al., 1966; NCES, 2021). Researchers have attempted to identify factors that influence these student outcomes (Jayavant, 2016). Leithwood et al. (2004) found that the practices and behaviors of building leaders "are second only to classroom instruction in school-related factors that contribute to what students learn at school" (p. 5). Based on their significant impact, research has been conducted to identify effective social justice and mainstream educational leadership …

Addressing The Teacher Shortage: A Study Of Local School Human Resource Efforts In Illinois, Sean C. Potts

Dissertations

Shortages of highly qualified teachers may be one of the greatest challenges school districts face today. This study is an exploration of how eight school districts in Illinois, ranging from rural to suburban and encompassing elementary, high school, and unit organizations, experienced the effects of a teacher shortage in 2021. The three primary research questions of this study included: (1) To what degree were local districts feeling the impact of the teacher shortage in Illinois, and how did those shortages manifest themselves?; (2) What factors did local human resource directors believe to be contributing most to any obstacles they may …

Integrating Media Literacy Into General Education Core Courses For Undergraduates, Christen Embry

Dissertations

This study aimed to understand the essential nature of media literacy, evaluate pre-developed higher education classes for existing media literacy context, and recommend best practices for incorporating media literacy into an undergraduate curriculum. This mixed-methods study of media literacy in undergraduate college courses explored the presence and absence of media literacy lessons within core classes by auditing 15 online course shells accessed through the university’s Learning Management System (LMS). Specifically, all the courses surveyed included the first skill of media literacy, Access; 33% of the classes included Analyze; 27% included Creation; 20% included Reflection; and 20% included Action. Once the …

A Dialogical Approach To Peer Coaching For Asset Pedagogies, Elisabeth Van Beek

Dissertations

The purpose of this study was to understand how dialogical peer coaching using an asset pedagogical framework supported the development of culturally sustaining pedagogy (Gay, 2000; Ladson-Billings, 1994; Paris & Alim, 2017). This action research study followed one teacher and eight emergent bilingual students during an intervention. The intervention consisted of asset projects developed from the funds of identity framework (Esteban-Guitart, 2016). The peer coaching process consisted of a period of observation followed by repeated co-planning, coteaching, and reflection. The researcher took a dialogical stance on creating asset projects with the students as well as peer coaching with the teacher …

The Graduate Record Examination And Graduate Admissions: Issues In Diversity, Lauren Rankin

Dissertations

Doctoral education is an expensive and difficult endeavor. Program faculty are interested in finding students who will be successful in completing their courses and obtaining employment. The Graduate Record Examination (GRE) is often used to assess a student’s readiness for the rigors of graduate education. A student’s readiness for doctoral education can be assessed through analyzing the predictive validity of the GRE with various outcomes such as grade point average, scholarly output, and time to completion. However, this measure may not predict success for all students with potential bias towards students who are international and linguistically diverse. A total of …

Mathematical Knowledge For Teaching As Decision-Making For The University Mathematician Developing Coherence In Review Of Discrete Mathematics, Julie Lang

Dissertations

Mathematicians teaching at the university level have a deep understanding and appreciation for the mathematics that they teach. However, they rarely receive much formal training in teaching. Thus, university mathematicians must rely on their mathematical understandings and personally developed ideas of teaching to guide their decision-making. Relatively little research exists on mathematicians’ teaching practices. The purpose of this study was to examine the mathematical knowledge for teaching (MKT) of a university mathematician teaching discrete mathematics and how he leveraged his knowledge to make decisions and develop coherence among mathematical ideas during a semester review. An enactivist perspective examining a mathematician’s …

Middle School Students’ Perceptions, Experiences, And Behaviors Towards Using A Virtual Reality Application To Build Molecules, Dalal Za'al Ali Alrmuny

Dissertations

To deliver successful integration of virtual reality (VR) technology into chemistry education, it is essential that students have clear and positive perceptions about the purpose and the value of such integration. An important part of establishing a plan for integrating virtual reality technology into chemistry education is to explore the current perceptions, experiences, and behaviors of students towards the use of VR technology to establish an initial baseline of skills and areas in need of development. The purpose of this exploratory mixed methods study was to explore the perceptions, experiences, and behaviors of 62 middle school students in the state …

An Ensemble Machine Learning Approach To Causal Inference In High-Dimensional Settings, Sami Saad Alanazi

Dissertations

The machine-learning algorithms have gained popularity and have gotten the attention of many researchers in the fields of statistics and computer sciences in recent decades. Due to their computational capabilities in big data, many researchers have been attempting to incorporate machine-learning in prediction and inference problems. One of the recent methods that got a lot of attentions was referred to as the double machine learning method (DML). This method attempts to estimate the effect of the treatment variable in the presence of high-dimensional nuisance function by incorporating machine-learning algorithms. Previous studies have shown that the DML method is able to …

Development Of The Teaching Twice Exceptional Students Scale, Michelle Ann Godzinski

Dissertations

Twice exceptional (2e) students are a unique population of students, who present with a wide range of strengths and weaknesses. For this reason, it is important for teachers to be trained and feel prepared to work with these students. Teacher self-efficacy has been shown to influence both student and personal outcomes (e.g. student perceptions of school, student academic success, teacher retention, etc). The Teaching Twice Exceptional Students Scale (TTESS) was developed as a way to measure teacher’s self-efficacy in regard to working with 2e students, so that districts may better identify gaps in knowledge or training that teachers may have. …

Understanding Creative Pedagogy Of Saudi High School Stem Teachers: Three Case Studies Of Mawhiba And Public Science Classes, Maryam Salman Bojulaia

Dissertations

The Saudi government recently emphasized creative thinking in the education context to change the country’s economy from an oil-based economy to a mindset-based economy (Vision 2030, n.d.). On the other hand, the recent version of the challenges in Saudi K-12 education indicates that significant obstacles impede the promotion of creative thinking. Conventional teaching methods focus on rote memorization and have limited concentration on science, technology, engineering, and mathematics (STEM) disciplines. This research aims to describe and compare the creative pedagogy experiences of STEM educators in a Mawhiba classroom (customized classroom for creative and gifted students) and a public classroom (for …

A Comparative Study Of Instructional Perspectives Among Learning And Development Practitioners, Merzudin Selimovic

Dissertations

The instructional perspectives of learning and development practitioners have a critical impact on their learners. This study aimed to determine if a relationship existed between years of experience of a learning and development practitioner and how they score on the seven factors of Henschke’s (1989) Modified Instructional Perspectives Inventory (MIPI). The MIPI consisted of seven factors: 1) Teacher Empathy with Learners, 2) Teacher Trust of Learners, 3) Planning and Delivery of Instruction, 4) Accommodating Learner Uniqueness, 5) Teacher Insensitivity Toward Learners, 6) Learner-centered Learning Process (Experience-based Learning Techniques), and 7) Teacher-centered Learning Process. The MIPI is a revised version of …