Digital Commons Network^™

Time Resolved X-Ray Spectroscopy Of Highly Charged Ar, Nd, And Pr, Timothy Burke

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Highly Charged Ions (HCIs) may be considered ideal mini-laboratory in which one can study the physics of matter and light in an environment of high internal electric field that can not be recreated with standard lab equipment. The remaining electron(s) exist in the extremely large electric field of the nucleus and therefore measurements of electronic transitions in these systems provide stringent tests of our understanding of physics in extreme conditions. Quantum electrodynamics (QED) despite being a powerful theory exhibits large discrepancies for systems under extreme conditions. The work here investigates the atomic properties within non-Maxwellian plasmas. The HCI plasmas studied …

Development Of Advanced Simulator-Based Metrics For Suturing Skills Assessment And Feedback, Simar Singh

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Vascular surgery demands highly skilled suturing to manipulate and connect delicate vasculature. However, inadequate methods for open suturing skills training necessitate efficient and objective methods to develop skills. To address this need, medical training simulators for objective surgical skills training are gaining popularity for their formative assessment.

This research details the development of a system to classify suturing performance and provide feedback on a suturing skills measurement and feedback platform (called the SutureCoach). The SutureCoach simulator offers a comprehensive assessment of skill through sensors measuring needle driver motions, membrane forces and torques, subcutaneous suture needle movement, and hand motions. We …

Mesenchymal Stromal Cell Response To Degenerated Intervertebral Disc-Like Ph, Kyle Cannon

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Intervertebral disc degeneration (IVDD) has become increasingly prevalent and is a common contributing factor to low back pain. There are currently no clinical treatment options for IVDD that alleviate the symptoms of IVDD while simultaneously promoting repair of IVD tissue. One treatment option being explored is intradiscal administration of mesenchymal stromal cells (MSCs). However, the microenvironment of the degenerating IVD places significant stress on both native IVD cells and implanted cells. There are several questions that need to be addressed which may help further inform the development of efficacious intradiscal MSC therapies for IVDD. These questions include: 1) Do MSCs …

Development Of Earthquake Hazard Prediction Software For South Carolina And Its Applications, Vishnu Saketh Jella

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This dissertation presents the development of earthquake hazard generation software, CarolinaShake and CarolinaADRS, for the state of South Carolina and its applications in the field of earthquake engineering. South Carolina is a seismically active state in the eastern United States, and there is a need to accurately quantify the earthquake hazard and incorporate it into the design of infrastructure systems. To achieve this objective, the South Carolina Department of Transportation (SCDOT) is actively supporting the initiatives to update its seismic design policies and procedures of civil infrastructure systems. As part of those initiatives, first, CarolinaShake, a Windows-based graphical user interface …

Crystalline Colloidal Arrays: Exploring Light-Matter Interactions, Haley W. Jones

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Understanding and manipulating quantum light-matter interactions, especially in the context of nanostructured environments, is highly critical for technological progress and inventive solutions in the fields of telecommunications, energy-efficient lighting, and cutting-edge quantum computing technologies. The fundamental interactions of photons with a surrounding environment directly impact the performance and efficiency of devices such as lasers, light-emitting diodes (LEDs), and quantum computing elements, which leverage the unique properties of confined structured environments. Since the late 1980s, the connection between a structured environment and the decay kinetics of an embedded fluorophore has been a highly debated and unresolved topic in the literature. More …

Identifying Temporomandibular Disorder Morphological Risk Factors Via Explainable Deep Learning And Multiscale Biomechanical Modeling, Shuchun Sun

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Clarifying multifactorial musculoskeletal disorder etiologies supports risk analysis and development of targeted prevention and treatment modalities. Deep learning enables comprehensive risk factor identification through systematic analysis of disease datasets but does not provide sufficient context for mechanistic understanding, limiting clinical applicability for etiological investigations. Conversely, multiscale biomechanical modeling can evaluate mechanistic etiology within the relevant biomechanical and physiological context. We propose a hybrid approach combining 3D explainable deep learning and multiscale biomechanical modeling; we applied this approach to investigate temporomandibular joint (TMJ) disorder etiology by systematically identifying risk factors and elucidating mechanistic relationships between risk factors and TMJ biomechanics and …

Design, Fabrication, And Characterization Of Advanced High-Power Single-Mode 9xxnm Semiconductor Lasers, Xiaolei Zhao

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This thesis presents the comprehensive design, fabrication, and demonstration of advanced high-power, high-efficiency single-mode semiconductor lasers operating at a wavelength of 9xxnm. We begin with the design of the laser epitaxial structure, serving as the cornerstone for achieving high-power high-efficiency lasers. Our methodology integrates a semi-analytical calculation model, which accounts for Longitudinal Spatial Hole Burning (LSHB) and Two-Photon Absorption (TPA) effects, facilitating a thorough exploration of how design parameters influence output power and conversion efficiency. This approach offers an effective and time-efficient epitaxial structure optimization strategy compared to conventional full 3D simulation models.

Subsequently, we demonstrate high-power, high-efficiency ridge waveguide …

Novel Nucleus Pulposus Biomaterial Development And Low Field Mri Assessment For Intervertebral Disc Degeneration, Mario Krussig

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Intervertebral disc degeneration (IVDD) is a prominent pathology in the modern world that causes debilitating pain for many patients. The onset of IVDD occurs in the nucleus pulposus (NP). NP biomaterials will play a vital role in mitigating the progression of IVDD. Within this work, we sought to synthesize a solubilized extracellular matrix (ECM)-based NP biomaterial. Utilizing pepsin or urea extraction, bovine NP ECM was successfully solubilized (SBNPs). SBNP formulations were characterized biochemically, evaluated for cytotoxicity, and down-selected for front-running formulations. Leading candidate SBNPs were incorporated into an alginate bead biomaterial model to determine the potential bioactivity with human adipose-derived …

Development And Application Of Discrete Element Models For Granular Materials - From Rigid Spheres To Complex-Shaped Flexible Particles With Breakage, Zakia Tasnim

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Granular materials, which can range from nanometers to centimeters, are widely encountered as particles or powders in nature and in engineered systems. Some examples of granular materials include sands, gravels, biomass feedstocks, rice grains, pharmaceutical pills, glass beads, and lunar or martian regolith simulants. The attributes of and the interactions between constituent particles dictate the bulk mechanical properties and behavior of granular materials. The discrete element method (DEM), a particle-based modeling technique, has become a useful numerical tool for modeling the bulk behavior (such as mechanical, flow, and breakage behavior) of granular materials, where interactions between the granular materials' individual …

Process-Structure-Property-Performance Modeling For Semicrystalline Thermoplastics And Composites, Tatiana Stepanova

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With a growing focus on reducing the adverse effects of transportation on the environment, industries are seeking fuel-efficient and sustainable solutions. Fuel efficiency can be improved in several ways, but structural lightweighting has demonstrated overall effectiveness. In this regard, thermoplastic composites and additive manufacturing (AM) thermoplastics have become viable candidates for use in the automotive industry, given the need for weight reduction and efficiency improvement.

The advantages of AM include simplifying supply chains, simplifying part geometry, and enabling mass customization. In order to design high-performance AM structures, extensive modeling and simulation are required. AM thermoplastics are similar to conventional manufacturing …

Engineering Multifunctional Silicon Nanostructures From Biorenewable Cellulose Nanocrystals, Nancy Chen

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The imperative search for alternative materials to address the pressing demand for advance energy storage is underscored by the escalating environmental predicaments. Lithium-ion batteries (LIBs) with graphite anodes have become the benchmark in energy storage; however, they are approaching a saturation point in terms of energy density. Silicon emerges as a promising contender to supplant graphite, owing to its profuse availability, cost-effectiveness, and impressive specific capacity of 4200 mAh g^-1. By integrating silicon anodes, LIBs stand to undergo a radical transformation, markedly diminishing in weight and size, thus heralding a novel wave of compact, lightweight energy storage systems. …

A Manufacturing-To-Response Pathway For Manufacturing Optimization Of Carbon Fiber Reinforced Polymer Composite Structures, Madhura Limaye

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Over the past decade, there has been an increased adoption of thermoplastic and thermoset based continuous carbon fiber reinforced polymer (CFRP) composites for structural applications in several industries. Among the different manufacturing methods, thermoforming process for thermoplastic based continuous CFRP’s offer a major advantage in reducing cycle times for large scale productions. Similarly, out-of-autoclave curing process for thermoset based continuous CFRP’s using heated tooling enables production of large composite structures. However, these manufacturing processes can have a significant impact on the structural performance of parts by inducing undesirable effects. These effects include inhomogeneous fiber orientations, thickness variations, and residual stresses …

Selected Topics On Sequential Designs For Decision Making, Caroline Kerfonta

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This dissertation is comprised of three parts. The first proposes a sequential approach to determine the experimental setting with the minimum variance (Kerfonta et al., 2024). Two acquisition functions are developed to assist developing the approach. Theoretical results along with a case study using data from crystallization experiments is conducted to show the ability of the proposed method to correctly select the experiment with the minimum variance. The second and third parts propose adaptations to the Bayesian optimization algorithm using transformed additive Gaussian processes (TAG) as the surrogate model. The goal of using the TAG framework is to decompose the …

Leaders In Science Education Communities, Jennifer Bateman

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This three paper dissertation investigates the role of the District Science Coordinator (DSC). Due to the lack of research, District Science Coordinators (DSCs) are frequently misidentified as Science Teacher Leaders (STLs). It is important to establish a clear distinction between the roles. This first paper explores the salient similarities and differences between STLs and DSCs, while also attending to their individual roles, responsibilities, and professional support.

This second paper examines how a synchronous, online professional learning (PL) experience resulted in the creation of a community of practice (CoP) among two different groups of participating district science coordinators (DSCs) and how …

Oscillations Of Capillary Surfaces With Volume And Edge Effects, Dingqian Ding

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Capillary surfaces are defined by an interface endowed with surface tension that is partially supported by a solid substrate and are susceptible to oscillations reflecting a balance between fluid inertia and the restorative force of surface tension. The wave dynamics strongly depend upon volume change within the domain and edge effects through the boundary conditions applied at the contact-line formed at the liquid-gas-solid interface, while the spatial wave structure conforms to the geometry of the capillary surface. This dissertation develops mathematical models to address these effects for several canonical capillary surfaces, which are organized into two parts that are focused …

Understanding The Experiences Of Para-Collegiate Student- Athletes: A Mixed Methods Study, Derek Whaley

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Experiences are the impressions developed through gaining, using, fostering, and sometimes disposing of a service or product. Recent years have shown an ongoing emphasis placed on experiences and their impacts; one of particular interest for this study are the experiences of para-collegiate student-athletes. Using the Experience Type Framework (ETF) and the Extraordinary Impact Scale (EIS), the purpose of this study was to understand the experience of involvement in intercollegiate sports among adaptive student-athletes. This study employed an explanatory sequential mixed methods design, using quantitative and qualitative data to understand the adaptive student-athlete experience. Phase I (n = 30) used the …

Robust And Trustworthy Deep Learning: Attacks, Defenses And Designs, Bingyin Zhao

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Deep neural networks (DNNs) have achieved unprecedented success in many fields. However, robustness and trustworthiness have become emerging concerns since DNNs are vulnerable to various attacks and susceptible to data distributional shifts. Attacks such as data poisoning and out-of-distribution scenarios such as natural corruption significantly undermine the performance and robustness of DNNs in model training and inference and impose uncertainty and insecurity on the deployment in real-world applications. Thus, it is crucial to investigate threats and challenges against deep neural networks, develop corresponding countermeasures, and dig into design tactics to secure their safety and reliability. The works investigated in this …

Structure And Dynamics Of Complex Fluids Formed By Ionomers: Experimental-Computational Insight, Chathurika Kosgallana

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The current study focuses on understanding the effect of clustering on the structure, dynamics, and response of ionomers in melts and solutions using neutron scattering methods combined with atomistic large-scale molecular dynamics (MD) simulations.

Ionizable polymers are used in a wide range of applications, such as in clean energy and biotechnology, where ion transport is integral to the application. Ionizable groups drive cluster formation and often become the dominating force in determining the structure and dynamics of these polymers.

The work consists of five studies. The first study probes the structure of sulfonated polystyrene in toluene solutions tweaked by the …

Domain Decomposition Methods For Fluid-Structure Interaction Problems Involving Elastic, Porous, Or Poroelastic Structures, Hemanta Kunwar

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We introduce two global-in-time domain decomposition methods, namely the Steklov-Poincare method and Schwarz waveform relaxation (SWR) method using Robin transmission conditions (or the Robin method), for solving fluid-structure interaction systems involving elastic, porous, or poroelastic structure. These methods allow us to formulate the coupled system as a space-time interface problem and apply iterative algorithms directly to the evolutionary problem. Each time-dependent fluid and the structure subdomain problem is solved independently, which enables the use of different time discretization schemes and time step sizes in the subsystems. This leads to an efficient way of simulating time-dependent multiphysics phenomena. For the fluid-porous …

Electrode Engineering For Enhanced Performance And Low-Cost Redox Flow Batteries, Abena Williams

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The Impact Of The Graphic Communications Outreach And Recruitment Program On The Gc Identity, Riley Dekrafft

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The present study evaluates the impact of Clemson Graphic Communication's Outreach and Recruitment program on high school students' perceptions of the major and their college and post-college opportunities. Through surveys and events sponsored by Outreach, the research aims to determine the overall influence of the GC program. Participating students, accompanied by their instructor and guardians, will visit Godfrey Hall, Clemson University's Graphic Communications building. Before the trip, students must complete a comprehensive survey gauging their understanding of the Graphic Communications program and its industry. During the visit, students will engage in rotational activities to experience the daily practices of Graphic …

Additive Manufacturing Of Porous Tungsten Carbide Structural Electrode Components Using Robocasting, James Bevis

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Thanks to ideal mechanical and electrochemical properties, Tungsten Carbide (WC) shows excellent potential as a structural electrode material for multifunctional devices. These devices have applications in electric vehicles, for example, structural fuel cells and massless batteries. In such a context, structural WC electrodes will also benefit from porosity to decrease their weight and increase their surface area and chemical reactivity. Porous WC is a useful material for this field because of its high strength-to-weight ratio and electrical properties. However, current manufacturing methods can be expensive, complex, and limited, so the intent is to provide a more simplistic and sustainable method …

Broadening The Application Range Of Cell-Free Protein Expression Systems, Matthew Becker

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Centralized protein manufacturing platforms make the delivery of needed therapies to places with limited infrastructure almost impossible. Cell-free protein expression systems, systems that utilize protein production machinery extracted from cells, offer these communities a viable protein expression platform that is robust and easily deliverable to the place of need. Much work in cell-free system engineering looks to increase the hardiness of cell-free system (CFS) components, like the extract and reaction buffer, needed to carry transcription and translation of gene therapeutic targets forward. Freeze- and air-drying of extract, reaction buffer, or both with certain additives, like sugar molecules, has been proposed …

Dynamics Of Link Importance Across Flood Disaster Phases And Flood Impacts On Operation Of An Industry, Navin Bhatta

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Transportation damage and disruptions will become increasingly common as the frequency of floods increases due to climate change. Given the size and cost of the transportation network construction, communities' mitigation measures should be supported by evaluations that cover both normal and disaster management phases. This thesis examines the criticality of road segments in the normal, flood response, and recovery phases, considering the effects on emergency services, healthcare, industry, education, recreation, and transit and analyses that whether a flood disrupts the operational trips of a company in Anderson County, South Carolina. A 100-year event and a 500-year flood event provides context …

Quantifying Hurricane Effects On Housing: Evaluating Damage, Loss, And Shelter Demands Using Historical And Simulated Storm Tracks, Adish Deep Shakya

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This research introduces an advanced framework which employs parametric wind field models for peak wind speeds, and building fragility curves, loss functions, and demographic data to estimate for estimating housing damage and loss. The uninhabitable units immediate displaced households, short-term and long-term shelter need households are determined. with a particular focus on those eligible for FEMA assistance. The framework's validity is reinforced by a high correlation in the analysis of recent hurricane events between estimated numbers of displaced households and actual FEMA aid recipients, where FEMA aids about 20-60% of the predicted long-term displaced households. A novel application of the …

Analysis Of Cnn Performance Utilizing Jpeg Compressed Images Created On An Fpga, Timothy Shaughnessy

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JPEG (Joint Photographic Experts Group) was formed in 1986 to create a method to reduce image size primarily for ease of transfer on the Internet. Released to the public in 1992, JPEG compression is a form of lossless compression that has been a staple for compressing images. JPEG is the go-to image compressor because it provides high compression ratios while maintaining visual integrity for the human eye. Growing image sizes have made JPEG compression increasingly relevant. It is vital to keep up with growing data sizes for improved image handling performance on an edge device like a Field-Programmable Gate Array …

Advancements Of A Breast Tissue Marker And Localization System, Azrin Jamison

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Breast cancer has become the most prominent cancer worldwide in women. Annual mammograms are encouraged for women of high risk to increase early detection allowing for lumpectomies rather than mastectomies to occur. Prior to a lumpectomy, a biopsy must be taken to determine if the tissue is cancerous, and a breast cancer biopsy marker (BBM) is left in the region of possible cancerous tissue. Wire localization has been the gold standard for localizing these BBMs. However, due to the reported patient discomfort and logistical inefficiencies faced by healthcare providers (HCP), non-wire localization solutions have been recently developed. This study aims …

The Post Pandemic Learner: How Spatial Dynamics & Accessibility Impact The Learning Experience, Erikka Misrahi

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The COVID-19 pandemic had unprecedented impacts on Generation Z (Gen Z) in regard to mental wellbeing and learning impacts. While the world shut down in March 2020, the majority of students who have since entered college were forced to attend some portion of high school using remote learning platforms. This transition, while necessary at the time, has had repercussions that are still being felt in higher education. These impacts, combined with the challenges that Gen Z were already experiencing due to the pressures of social media, and the impacts that technology has had on attention spans, have changed their learning …

Biotinylated Protein Capture And Tween-20 Assisted Exosome Isolations Via Capillary Chanelled Polymer Fiber, Md Khalid Bin Islam

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In the past two decades, Marcus and colleagues have led the advancement of capillary-channeled polymer (C-CP) fiber stationary phases for biomacromolecule separations, including proteins and nanovesicles. These stationary phases offer notable advantages, including low cost ($5/column), straightforward column fabrication, and the capacity for on-column surface modification, enabling high chemical selectivity. This study examines a C-CP fiber modification strategy for capturing target proteins and develops a Tween-20-assisted C-CP-based hydrophobic interaction chromatography (HIC) method for the isolation and quantification of exosomes from human urine.

The quest for higher-throughput and cost-effective protein isolation techniques remains a key focus in a variety of end …

Laboratory Evaluation Of Remediation Alternatives For Groundwater At The Lane Street Superfund Site, Alyssa Costello

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At the Lane Street Groundwater Contamination Superfund site in Elkhart, Indiana, which includes industrial, commercial, and residential properties, a plume of contaminated groundwater was identified that requires remediation. The plume is chiefly composed of trichloroethylene (TCE) and has impacted residents’ drinking water. A microcosm study was performed to evaluate the potential of various treatment methods to remediate the Lane Street Superfund Site groundwater. The objectives of this microcosm study are to evaluate the potential for biostimulation, bioaugmentation, and abiotic degradation for implementation at this Site and to evaluate toxicity factors that have precluded natural degradation of the site contaminants. The …