Digital Commons Network^™

On Parallelization Of Graph Algorithms, Performance Modelling And Autonomous 3d Printable Object Synthesis, Shams-Ul-Haq Syed

Theses and Dissertations

The degree of hardware level parallelism offered by today’s GPU architecture makes it ideal for problem domains with massive inherent parallelism potential, fields such as computer vision, image processing, graph theory and graph computations. We have identified three problem areas for purpose of this research dissertation, under the umbrella of performance improvement by harnessing the power of GPUs for novel applications. The first area is concerned with k-vertex connectivity in graph theory, the second area deals performance evaluation using extended roofline models for GPU parallel applications and finally the third problem area is related to synthesis 3D printable objects from …

Student Experiences With Self-Determination And Agency: Centering Disabled Voices Through Photovoice, Rebecca Boineau Smith Hill

Theses and Dissertations

Young adults with intellectual and developmental disability (IDD) are less likely than young adults without disability to be employed, enrolled in postsecondary education, or live independently after high school (Lauer & Houtenville, 2017; Newman, et al., 2011). Self-determination, or the freedom to act as the primary causal agent in one’s life (Palmer & Wehmeyer, 1998), is a well-documented component of enhanced quality of life (Shogren et al., 2017) and a predictor of postschool success (Mazzotti et al., 2021; Test et al. 2009) for students with disabilities. People with IDD are less self-determined than their nondisabled peers, and often less self-determined …

Field Implementation Of A Stereo Vision System For Rnt And Stress Measurements In Cwr, Brittany Stinson

Theses and Dissertations

The use of Continuous Welded Rail (CWR) provides many advantages to the rail industry compared to the alternatively used jointed-track segments. However, one significant disadvantage is the development of thermal stresses longitudinally in the rail, which is not of concern when expansion joints are used. This is due to CWR’s inability to release thermal expansion in the absence of joints. The Rail Neutral Temperature (RNT) is the temperature at which the rail is in a stress-free state. A desired RNT is calculated based on local climate conditions and CWR installation practices are implemented to set the desired RNT at installation. …

Experimental And Computational Understanding Of Solid Oxide Iron Air Battery Performance, Chaitali Morey

Theses and Dissertations

Long-duration energy storage (LDES) (10+ hours) is considered a key technical solution for a widespread penetration of renewable energy into the utility market. However, the currently available storage technologies are limited to less than 10 hours for cost reasons. The benchmark Li-ion battery technology would be economically prohibitive if the storage time goes beyond 4 hours. Therefore, developing new low-cost LDES-compatible battery technologies is highly desirable. A solid oxide iron air battery (SOIAB) has been developed which consists of a reversible solid oxide cell (RSOC) and energy storage unit (ESU) of an iron bed. This battery is considered a promising …

High-Rate Production Of Thermoplastic Composite Structures For Urban Air Mobility Vehicles Utilizing Fastener-Free Assembly Methods, Robert H. Shumpert

Theses and Dissertations

This study aimed to develop a manufacturing plan for a Thermoplastic fiber-reinforced propeller blade for urban air mobility applications. This propeller blade offer a few unique challenges including the complex geometries of the blade. Another important aspect of the blade is using fusion bonding methods to increase the strength of joints in the product while reducing weight from fasteners and adhesives. This manufacturing process will be validated by producing a physical demonstrator to ascertain the efficacy of the manufacturing techniques used. First, the techniques that will make up the manufacturing plan must be selected. To do this, a review of …

Towards The Induction Welding Of Complex, Curved Thermoplastic Composite Structures, Andrew Cole Cromer

Theses and Dissertations

Recent advancements in the aerospace industry, coupled with the anticipated future significance of air travel, have spurred research aimed at increasing manufacturing production and aircraft flying efficiency by implementing new materials and assembly methods. Advanced air mobility (AAM), a subset of the aerospace industry, is anticipated to become a crucial component of the transportation infrastructure in densely populated regions. To meet the expected demand, there is a need for investigations into novel manufacturing and joining methods. This industry necessitates materials that are lightweight, durable, and amenable to high-rate production. One potential avenue under exploration is the utilization of thermoplastic composites. …

Modulation Of Neurodegenerative Disease Progression By Antioxidant Status, Elena Kelety

Theses and Dissertations

Neurodegenerative diseases, including Amyotrophic lateral sclerosis, Alzheimer's disease, and Parkinson's disease, profoundly impact the brain and nervous system. In 2019, the United States reported the highest global prevalence of neurological disorders. This thesis approaches neurodegenerative diseases by emphasizing the critical role of a well-maintained antioxidant system, its intricate relationship with dietary patterns, and proposes an alternative fate of the antioxidant urate.

Neurodegenerative disease pathogenesis involves a complex interplay of neuroinflammation, mitochondrial dysfunction, misfolded proteins, and oxidative stress. Oxidative stress arises from an imbalance in the antioxidant defense system and the production of reactive oxygen species. Synergistic antioxidant interactions are vital …

The Gendered Patterns Of International Migration Systems: The Role Of Need For Care, Chang-Yi Lin

Theses and Dissertations

The demand for feminized jobs in developed countries—e.g., care, domestic, and entertainment work—has provided women with an opportunity to work abroad independently. However, while numerous studies have discussed gendered opportunities and barriers to women’s migration, few studies have examined these correlates globally. According to traditional gender norms, one such potential barrier is women’s childcare responsibilities at home and, more specifically, the number of children who need to be cared for. Here it is argued that, contrary to men, the higher the number of children who need to be cared for in a given country, the more difficult it would be …

Dynamic Response Evaluation Of Loose Gravelly Soils In Centrifuge Modeling Experiments, Siwadol Dejphumee

Theses and Dissertations

Dynamic behavior of gravelly soil has gained more attention in recent years as several case histories of liquefaction of gravelly soil have been reported. Liquefaction can cause failure of infrastructure, leading to economic damage and loss of life. Gravelly soil has unique characteristics and engineering benefits, providing a prevalent and versatile construction material for various infrastructure projects. Therefore, understanding of the gravelly soil behavior under seismic load is critical for assessing the resilience of infrastructure located in seismically active regions. To date, only a few experimental research studies have focused on the dynamic response of gravelly soil, and these studies …

Exiting Inflation With A Smooth Scale Factor, Harry Oslislo

Theses and Dissertations

The expectation that the physical expansion of space occurs smoothly may be expressed mathematically as a requirement for continuity in the time derivative of the metric scale factor of the Friedmann–Robertson–Walker cosmology. We explore the consequences of imposing such a smoothness requirement, examining the forms of possible interpolating functions between the end of inflation and subsequent radiation- or matter-dominated eras, using a straightforward geometric model of the interpolating behavior. We quantify the magnitude of the cusp found in a direct transition from the end of slow roll inflation to the subsequent era, analyze the validity several smooth interpolator candidates, and …

Unpacking The Relationship Between Legitimacy, Procedural Justice, Identity, And Desistance, Qassim Bolaji

Theses and Dissertations

Knowing why people stop offending over time and the criminal justice agencies' role in this process is essential for designing effective crime control interventions. Legal authorities have the core function of ensuring that social norms and laws are obeyed. However, the coercive and punitive tactics that police, judicial, and penal authorities typically resort to have been shown to have only limited impact on controlling and preventing crime while having the unintended consequence of worsening the public's perception of their institutional legitimacy. Specific to policing, the use of coercive policing tactics and their perceived ineffectiveness has, in recent decades, led to …

Native American Nationalism: Chickasaw Identity And The Music Of Jerod Impichchaachaaha' Tate, Austin Davis

Theses and Dissertations

Native American nationalism in classical music has yet to be seriously researched and is not taught in music academia. One of the more well-known contemporary Native American composers is Chickasaw composer Jerod Impichchaachaaha’ Tate (b. 1968). Throughout his career, Tate has explored and expressed his identity as a Native American and Chickasaw citizen through his music. As a result, his compositional output is a rich resource for examining what Native American nationalism in classical music looks like and how it is utilized in his works.

In this document, I analyze three of Tate’s pieces written for orchestra: Tracing Mississippi, Ghost …

Crystal Plasticity Modeling Of Heterogeneous Microstructure Of Additively Manufactured Metals, Md Mahabubur Rohoman

Theses and Dissertations

Additive manufacturing (AM) has emerged as a promising technique in the manufacturing industry for producing complex metal components as it provides shape freedom and simplistic processing chain.

Powder bed fusion is the widely used AM technique that uses laser or electron beam as the energy source to melt the metal powder and deposit it in a layer-by-layer fashion. While doing so, the previously molten layers are constantly are in re-heating and re-cooling processes which end up creating an intricate solidification for the deposited layers. Due to the complexity involved in the thermal cycles for the solidification process, columnar grains develop. …

Maternal-Child Cortisol Attunement Differs In Preschoolers With Autism, Fragile X Syndrome, And Neurotypical Development, Rachel Hantman

Theses and Dissertations

Early maternal-child attunement sets a critical foundation for later social development. While maternal and child cortisol attunement in neurotypical (NT) development has been clearly established, little research has examined these relations in neurodevelopmental populations, such as those with autism spectrum disorder (ASD) and Fragile X Syndrome (FXS). Given their elevated-risk for disrupted maternal-child attunement and given elevated stress and dysregulated cortisol patterns in both children with ASD and FXS and their parents independently, this is a critical gap. This study addressed this gap in the literature by examining early maternal-child cortisol attunement in 97 mother-child dyads (_nNT = …

Detection And Analysis Of Solid-Phase Nutrients In Complex Benthic Cyanobacterium Communities, Cassidy Ann Crandell

Theses and Dissertations

Eutrophication is one of the most serious water quality issues affecting aquatic systems in the United States. Densely populated urban areas as well as mining and agriculture are major sources of anthropogenic nutrient loading into lakes and rivers. Excess loading of nutrients like phosphorus (P) into these ecosystems can cause native algal species to be outcompeted by harmful algal bloom (HAB) species. Increases in these HAB events are a growing public health concern as contact with excreted toxins can be harmful for human, aquatic, and land species. Remediation techniques like total maximum daily loads (TMDLs) have been implemented to reduce …

Coastal And Inland Flooding - From Advanced Hydrodynamics And Data-Driven Modeling To Multi-Variate Coastal Vulnerability Assessment, Ahad Hasan Tanim

Theses and Dissertations

Flood risks in coastal and inland areas have historically been underestimated and underpredicted, resulting in increased flood damage and loss of human life. Flood risk under climate change and sea level rise will disproportionately impact low-wealth and marginalized communities, as they are often located in areas with less flood protection and have limited resources to adapt to the impacts of flooding. The systematic workflow of the life cycle of FRM is frequently disengaged in the current state of flood hazard assessment with system vulnerability assessment. This research aims to improve the life cycle of FRM by incorporating flood observation, monitoring, …

Dysregulation Of Dopamine Dynamics Through Monoamine Transporters By The Hiv-1 Protein Transactivator Of Transcription, Sarah Davis

Theses and Dissertations

Prevalence of HIV-1 Associated Cognitive Disorders (HAND) persists in the era of combined antiretroviral therapies, causing impaired memory, motor function, and decreased quality of life. Evidence from clinical samples of persons with HAND has implicated dopamine, as well as the HIV-1 viral protein transactivator of transcription (Tat) as key molecules associated with disease progression. Through molecular modeling, in vitro and in vivo mutagenesis our lab has characterized Tat as a negative allosteric modulator for monoamine transporters, including the dopamine transporter (DAT), vesicular monoamine transporter (VMAT-2), and norepinephrine transporter. While this work has shed light on how Tat impacts the function …

Investigating Arctic Ocean Freshwater Content And Circulation In A Changing Climate, Emma Louise Hoffman

Theses and Dissertations

The Arctic Ocean is unique among the world’s oceans, characterized by its cold temperatures, salinity-driven vertical structure, and shallow shelf seas. It has warmed intensely since the 1980s at rates exceeding the global average. This Arctic Amplification drives variability in sea ice and salinity, affecting local circulation and exchange with other basins, leading to global changes in oceanic and atmospheric circulation and the biosphere. This thesis explores changing dynamics in the Arctic Ocean, in particular connecting modeled changes in liquid freshwater content (FWC) and its pathways with major ocean circulation patterns, atmospheric drivers, and large-scale climatic changes.

This research combines …

Stem Identity In African American Middle School Students: A Phenomenological Study, Amara L. Alexander

Theses and Dissertations

Using a phenomenological approach, this action research study explored the influence of culturally sustaining teaching practices (Ladson-Billings, 2014; Paris 2012, 2021) to impact African American students STEM identity (Collins & Roberson, 2020). Qualitative data were generated through interviews with students, practitioner reflective notes, and classroom observations during the intervention. Analysis and interpretation of the data indicated student- participants had positive experiences during the intervention and the culturally sustaining STEM lessons positively impacted African American middle school students STEM identity. The implications of these findings for STEM curriculum writers, STEM education and STEM educators, particularly those in K-12 education.

The Effectiveness Of Equivalence-Based Instruction On Time-Telling Skills In Children With Moderate Developmental Disabilities Including Autism Spectrum Disorder And Intellectual Disability, Rongzhi Li

Theses and Dissertations

The purpose of this study was to evaluate the effectiveness of equivalence-based instruction (EBI) on teaching time-telling skills to children with moderate developmental disabilities including autism spectrum disorder (ASD) and intellectual disability. Three children with ASD or intellectual disability participated in the study. The experiment was conducted using a concurrent multiple baseline design across subjects. During the acquisition training, each participant was taught 24 discrimination relations including matching 12 picture analog clock faces and 12 printed digital clocks to their dictated times. After the training, the participants were assessed to see whether their visual-visual responses (transitivity relations) and oral naming …

Kodály Learning: A Qualitative Case Study Based On The Use Of A Blended Curriculum Using The Principles Of Zoltán Kodály In Beginning Piano Study, Megan Elizabeth Rich

Theses and Dissertations

This paper and its corresponding study were created to explore the effectiveness of the Kodály Method on traditional piano lessons and to hone a curriculum with long-term student musicianship at its core. The curriculum was written for a six-week period and intended for students ages six–eight years old. The curriculum follows the melodic and rhythmic sequences of the Kodály Method and blends these sequences with traditional approaches to beginning piano lessons. The purpose of the study is to share and evaluate this curriculum and its results as they pertain to the four study participants.

The study was conducted over a …

Association Between Autoimmune Diseases And Lymphoma Risk Using The Uk Biobank, Hannah Grace Dice

Theses and Dissertations

Background. Lymphoma is a blood cancer that develops when white blood cells multiply in an abnormal way and collect in the lymph nodes. Autoimmune diseases result when the immune system is overactive, causing it to attack and damage the body’s own tissues. Limited studies have been conducted to investigate the association between autoimmune diseases and lymphoma risk.

Literature review. Based on prior research, six autoimmune diseases (rheumatoid arthritis (RA), lupus, Sjögren’s syndrome, sarcoidosis, Crohn’s disease, and ulcerative colitis (UC)) were examined to better understand their association with lymphoma risk. Prior research has concluded that certain aspects of these autoimmune diseases …

State Estimation And Prediction Based On Simplified First Principle Model Of Lithium-Ion Batteries In Lebesgue Sampling Framework, Enhui Liu

Theses and Dissertations

State-of-charge (SOC) and remaining-dischargeable-time (RDT) are critical states of Lithium-ion batteries (LIBs). SOC indicates the available charge stored in LIBs compared to the total charge capacity of LIBs, while RDT refers to the remaining dischargeable time that LIBs can support under given loading profiles. Accurate SOC estimation and RDT prediction play important roles in guaranteeing the safe and efficient operation of batteries in real applications.

Taking advantage of high fidelity of simplified first principle (SFP) model of LIBs, this research aims to accurately estimate SOC and predict RDT. Firstly, this research establishes an SFP model to describe the battery internal …

Placebos, Rhetoric, And The Power Of Expectation, Jennifer M. Reeher

Theses and Dissertations

Placebos, Rhetoric, and the Power of Expectation examines the relationship between persuasion and health to determine what interventions rhetoric could make in the interdisciplinary field of placebo studies. This exploration of the relationship between rhetoric and placebo responses relies on non-anthropocentric definitions and theories of rhetoric as well as a multifaceted archive that includes patient narratives, clinical intake forms, and peer-reviewed scientific studies of condition-specific placebo responses. The impact of this investigation spans the practical and the theoretical. First, rhetorical study highlights the importance of a patient’s perception of care in patient recovery. To this end, rhetoric offers audience-focused methods …

Use Of Improvement Science To Build The Instructional Capacity Of Faculty In A Community College, Marianne Yohannan

Theses and Dissertations

Up to 78% of Science, Technology, Engineering and Mathematics (STEM) students experience poor academic achievement as defined by course grades of D, F and W in college. Students entering these fields are often not prepared (Chen & Soldner, 2013) and struggle to succeed in gateway STEM courses, with one-third of them possibly failing (Freeman et al., 2011). The success rates are lower among first-generation, low-income, and underrepresented minoritized groups (Doerschuk et al., 2016). At Tri-County Technical College, 30-40% of introductory biology students are unsuccessful and receive low grades (Institutional Research, n.d.). Low academic achievement has a huge impact on our …

Statistical Inference Based On Elliptically Symmetric Distributions For Directional Data, Zehao Yu

Theses and Dissertations

Directional data arise in many scientific fields such as meteorology, oceanography, geology, zoology, and biomechanics. Geometrically, directional data lie in a spherical space. Although not in a spherical space, compositional data, such as microbiome data, can be mapped from a simplex to a spherical space via the component-wise square-root transformation. Other examples where compositional data emerge as a subject of interest include compositions of minerals in rocks, compositions of chemical mixtures, investment portfolios, and demographic composition of a population. This dissertation aims to develop inference procedures for analyzing directional data in general initially, with later focus shifted to the transformed …

Development Of Dip-Coated Carbon Fibers For Structural Power Composites And Optimization Of Bus Plates For Passively Propagation Resistant Batteries, David Petrushenko

Theses and Dissertations

Increasing demand for lithium-ion batteries in electric vehicles, portable electronics, and electric aircraft is a driving force for the expansion in new battery architectures to achieve higher gravimetric and volumetric efficiencies. In practice, maximizing energy density can be achieved by introducing state-of-the-art materials to increase the capacity of cells or by reducing the system's mass by incorporating lightweight structural materials. An alternative approach is to develop systems capable of performing multiple functions simultaneously that combine mono-functions of the battery and vehicular structure in a multifunctional component capable of storing electrical energy and providing structural support.

The initial focus of this …

Molecular And Hybrid Catalysts For Selective Hydrodeoxygenation Of Lignin Model Compounds, Jacob G. Tillou

Theses and Dissertations

Lignin is a highly aromatic, branched polymer and could be utilized as a renewable source of liquid fuel. The advent of “lignin-first” depolymerization processes have allowed for the high-yield isolation of oxygenated aromatic monomers from lignin. These oxygenated aromatic compounds are lower in energy and stability than their deoxygenated counterparts. Selective deoxygenation of these compounds would result in stable, higher value liquid fuels. Using molecular catalysts, selective deoxygenation, or hydrodeoxygenation (HDO), of lignin-derived compounds in the presence of hydrogen is possible.

Immobilization of these molecular catalysts on metal oxide surfaces eliminates the possibility of bimolecular decomposition and allows for easier …

Associations Between Infant Vagal Regulation, Early Social Communication, And Socidemographic Risk, Tessa Djiko

Theses and Dissertations

Respiratory sinus arrythmia (RSA), a measure of parasympathetic nervous system activation, has been linked to socioemotional and language development (Porges, 2007; Thayer & Lane, 2000). Children diagnosed with autism spectrum disorder (ASD) show lower RSA (Patriquin et al., 2011) while both children with ASD and children from lower SES backgrounds show differences in early social-communication development (Jones-Mason et al., 2018). However, little is known about interactions between sociodemographic risk and physiological regulation within the context of ASD and social-communication development. The present study addresses this gap by examining the relationship between RSA (as indexed by RSA suppression and resting-state RSA), …

British Fortification Strategy In The South Carolina Backcountry During The Southern Campaign Of The American Revolution: Archaeological And Historical Perspectives On Infrastructure And Landscape, Charles Brian Mabelitini

Theses and Dissertations

During the Southern Campaign of the American Revolution, the British military established a series of fortified posts to secure the South Carolina backcountry. This chain of posts was comprised of at least 25 fortified positions that extended in an east-west arc from Georgetown, South Carolina, at the mouth of the Pee Dee River to the village of Augusta, Georgia, on the Savannah River. This dissertation examines the British fortification strategy in the South Carolina backcountry during the Southern Campaign from the anthropological perspective of infrastructure theory. It also examines the archaeological landscape of these positions to better understand their strategic …