Machine Learning Based Medical Ultrasound Image Classification And Grad-Cam Interpretation, Victoria C. Hemphill

All Theses

This work takes a step in creating a diagnostic tool for the classification decision process of Achilles tendinopathy using ultrasound images. An attention-based multiple instance learning model is developed to classify the images. Typically, doctors capture multiple ultrasound images of the Achilles tendon during a study to determine a complete diagnosis. Multiple instance models adopt this behavior by providing a single label for a set of instances (images). The images are grouped into ”bags” at the study level and passed into the model. The MIL model then uses its attention property to assign an importance score to each image to …

Visor-Zt: A Visibility, Simulation, And Operational Resilience Framework For Zero Trust Security In Ros 2, Noah Tinker

All Theses

Robotic systems are becoming more and more prevalent in modern society, with Robot Operating System 2 (ROS 2) being the dominant operating system for these implementations. Its popularity can be attributed to its design, which is purpose-built for distributed systems and asynchronous communications. However, ROS 2 security is static and therefore less capable of responding to contemporary threats and network behavior. This becomes a greater issue when considering its applications in the military and defense sectors, where security is of the highest importance. In recent years, the U.S. Department of Defense (DoD) has implemented zero trust (ZT) security based on …

A Generalizable And Privacy-Preserving Framework For Anomaly Detection In Heterogeneous Iot Environments, Mahshid Rezakhani

All Theses

With the rapid growth of Internet of Things (IoT) devices across various sectors, detecting anomalies in such systems has become increasingly challenging. IoT environments produce diverse and evolving data streams, often lacking labeled examples, which limits the effectiveness of traditional machine learning models. These models typically require frequent retraining and struggle to adapt to new deployment conditions. This thesis proposes a flexible, privacy-aware framework for anomaly detection in multivariate time series data generated by heterogeneous IoT systems. The approach integrates a long short-term memory variational autoencoder (LSTM-VAE) with contrastive learning and adversarial adaptation, enabling the model to generalize across domains, …

Polyphenols For The Mitigation Of Vascular Calcification; In Vitro And In Vivo Studies, Abdullah Altuhami

All Theses

Globally, cardiovascular diseases, in most cases associated with calcification, are the main cause of death. However, currently, the only effective cure is to undergo surgery to augment or receive a healthy donor heart, which could be very difficult due to the long waiting list and the associated risks. The possibility of body rejection of the foreign organs is attributed to immunoreaction or the risk of infection, since the donor must be on immunosuppressant drugs that lower the body's immunity and facilitate the body's acceptance of the new organ as one of its own. Taking that into consideration, using tissue-engineered vascular …

Grain Boundary Migration And Radiation Induced Segregation In Fe-Cr Alloys, Mohit Dhoriya

All Theses

Radiation-induced segregation (RIS) is a significant phenomenon that occurs in alloys subjected to irradiation, particularly in environments such as nuclear reactors. This thesis investigates RIS in ferritic Fe- Cr alloys through the use of Atomic Kinetic Monte Carlo (AKMC) simulations, focusing on the interaction between solute atoms and migrating grain boundaries. The study explores the influence of temperature, solute concentration, and grain boundary velocity on solute drag, a critical process driving RIS. The results show that solute migration is strongly influenced by the presence of vacancies and interstitials generated under irradiation, which are absorbed by grain boundaries and other defect …

Effect Of Cigarette Smoke Extract And Nutrient Deficiency On Energy Metabolism And Biosynthesis: An In Vitro Intervertebral Disc Explant Culture Study, Avery E. Madden

All Theses

Low back pain consistently ranks among the leading causes of disability worldwide, with degenerative changes in spinal intervertebral discs (IVDs) recognized as a key contributor. Degeneration arises from the disruption of mechanical and biological cues within the disc’s cartilaginous tissue, often exacerbated by aging or injury. In recent decades, cigarette smoking has also been identified as a significant risk factor, as IVD degeneration is more prevalent among individuals with a history of smoking. Smoke inhalation is thought to promote degeneration both directly, by exposing cells to water-soluble toxic chemicals in smoke; and indirectly, through nutrient deficiency resulting from vasoconstriction and …

Effects Of Variation In Altitude And Temperature On The Restraining Force And Internal Gauge Pressure Of Constrained Dunnage Airbags, Charles R. Weaver

All Theses

Dunnage airbags are an increasingly popular choice for securing cargo. During transit, changes in ambient temperature and pressure can cause airbags to expand generating damaging horizontal compressive forces in the trailer or container. Previous studies have developed numerical models for the behavior of Kraft paper and woven polypropylene fabric dunnage airbags under standard conditions but do not account for the behavior of airbags under varied altitudes and temperatures. This study provides empirical data on the internal gauge pressure and restraining force dynamics of 4-ply Kraft, woven polypropylene, and polyvinyl chloride airbags under simulated altitude and temperature conditions. Tensile testing characterizes …

Determining The Impact Of Surface Roughness On Disinfection Efficacy Of Commercial Products Against Pseudomonas Aeruginosa And Staphylococcus Aureus Wet Surface Biofilms, Kayley Stallings

All Theses

Biofilms are resistant to many stressors including disinfectant treatments. Disinfection may be further complicated by biofilms formed on damaged surfaces, as the damaged parts provide bacteria a better place to attach and grow. To better understand the risks, a new method to standardize surface scratching, to emulate worn surfaces via surface roughness changes was developed. These surfaces were used to grow biofilms with an adapted standardized EPA method to determine disinfection efficacy differences on scratched and non-scratched high-density polyethylene (HDPE) and stainless steel (SS) coupons treated with commercial disinfectants [hypochlorite (CL)-based, hydrogen peroxide (HP)-based, and quaternary ammonium (QA)-based]. Post-80 grit …

Cultivation Of Botryococcus Braunii For The Production Of Hydrocarbons Suitable For Fuel Use, Bryan C. Carroll

All Theses

Energy security, rural poverty, and climate change are pressing issues of our time. Biofuels provide a solution to these issues, with a focus on sustainable aviation fuel, SAF, due to compatibility with aircraft infrastructure and energy density. This research aims to review and produce knowledge about a specific microalga, Botryococcus braunii, for its potential for SAF. First a literature review on the process was conducted followed by an experimental study on the impact of aqueous media and inorganic carbon its growth and hydrocarbon content. The literature review found the process consists of cultivation followed by lipid extraction or hydrothermal …

Quantifying The Effect Of Initial Molecular Weight Distribution On The Degradation Of Linear Polyethylene At High Temperatures Using Dissipative Particle Dynamics, Cassandra L. Simpson

All Theses

Polyolefins are the primary contributors to greenhouse gas emissions and supply chain energy requirements with respect to other commodity polymers. In order to explore more efficient methods for recycling and upcycling these plastics, it is important to consider the kinetics of polymer fragments during the degradation process to more accurately reflect experimental outcomes. The molecular weight distribution of synthetic polymers is an important factor to consider when synthesizing, processing, and manufacturing industrial plastics. The breadth of this distribution, or dispersity, is determined by the ratio of the weight average molecular weight to the number average molecular weight, and is correlated …

A Comparative Study Of Land Use Regulations And Impact On Coastal Estuaries, Mabel W. Dadzie

All Theses

The study presents a mixed method and longitudinal assessment of land cover change, estuarine land loss, and policy implemented to address the past and anticipated estuarine losses in the Cooper River and North and South Santee watershed over the past twenty years. This study uses National Land Cover Dataset from 2001 to 2021, NOAA’s SLR projection data and planning documents from 1990 to 2025 to examine policy evolution among ten major themes. The results illustrate significant changes in land cover, notably the transition of wetlands, agriculture, and forests to developed land, as well as an evident spike in the integration …

Impact Of Cysteine And Tyrosine Dipeptides On Cho Cell Performance In A Perfusion Mimic, Corrin L. Pruitt

All Theses

Perfusion cell cultures typically achieve higher cell densities and generate higher volumetric productivities than fed-batch cultures due to continuous nutrient supply and spent media removal. Despite these advantages, perfusion cell cultures remain underutilized for licensed product manufacturing, primarily due to the lack of small-scale perfusion models for high-throughput process development and the complexities involved in media formulation capable of supporting high cell densities during long-term continuous operation. To avoid nutrient limitation at high cell densities, current perfusion processes rely on using higher perfusion rates, which results in significant media wastage and downstream product dilution. Therefore, there has been an effort …

Exploring Commuter Cyclists' Experiences Commuting In And Around Clemson University, Trevor S. Romans

All Theses

Climate change is a global issue, and high rates of automobile usage contribute to substantial social, environmental, and economic issues. One potential partial solution is creating bicycle-friendly communities. Research suggests that bicycle use leads to benefits in physical health, environmental sustainability, economic savings, and social justice. Research supports the roles of infrastructure development, safety policies, and other transportation planning initiatives in increasing bicycling, but less research has been completed about what is needed to develop bicycle-friendly communities. While physical infrastructure affects willingness to commute by bicycle, research suggests that understanding psychological factors and other behavioral aspects is also important for …

Life Cycle Assessment Of Sustainable Wastewater Systems - Algae-Based Wastewater Treatment, Harish Lakshmi Srinivasan

All Theses

This thesis studies the integration of an algae-based membrane bioreactor (MBR) and photobioreactor system into a domestic wastewater treatment facility, using the Clemson University WWTP as a reference plant. The proposed system replaces the conventional sequencing batch reactor and aerobic digester with a microalgae-bacteria symbiosis process, coupled with submerged ceramic membranes, an algal photobioreactor and anaerobic digestion for enhanced nutrient and energy recovery, which paves the way for water reuse and increased biological capacity in the future.

The study shows that overall energy consumption is reduced by approximately 18% compared to the existing conventional configuration. Further, methane production from anaerobic …

Advancing Multi-Physics Modeling For Microwave Heating: Application In Micro-Reactor Design And Optimization, Raghav Adhikari

All Theses

Microreactors are a type of small-scale chemical reactors for achieving reduced volume, improved product selectivity and higher reaction rate. It allows precise temperature control, which is crucial for sensitive chemical processes. Microreactors can be employed as key components of conducting small-scale reactions with improved reactor configuration and process efficiency. It is important to identify a localized and precise heating mechanism to trigger and control the corresponding chemical reactions.

In fact, microwave heating has gathered significant attention in recent years due to its ability to deliver efficient, rapid, and localized heating, which can accelerate reaction rates and enhances the reaction selectivity. …

Low Energy Ion Irradiation Effects In Electronic Devices And Materials, David C. Mccall

All Dissertations

The physics and engineering of ion-solid interactions are governed by the ion beam characteristics (flux, charge, energy) and target(s) in question. Here I present work on two projects related to the extraction of a high flux of low charge state Argon ions from a commercial plasma source and the irradiation of an engineered target, a transistor, with high charge state Argon ions.

An end-Hall ion source that produces a a high current plasma of ions and electrons in a rough vacuum environment is characterized. Using a Langmuir probe and multiple pressure measurements, the ion and electron content of the source …

Developing Guidance For The Use Of Floating Treatment Wetlands In Brackish Stormwater Ponds, Clare Escamilla

All Dissertations

Stormwater ponds are commonly used as a flood control strategy, particularly in coastal developments. Many coastal stormwater ponds are impaired with high nutrient levels that can lead to algal blooms, impacting the water quality of the pond and surrounding ecosystem. Floating treatment wetlands (FTWs) are one potential strategy that can be implemented in stormwater ponds to reduce high nutrient concentrations, however limited research has been done in brackish waterbodies. To determine the suitability of using FTWs in brackish stormwater ponds this research focused on (1) coastal resident perceptions of FTWs and (2) plants that can be utilized in FTWs deployed …

Experimental Evaluation And Comparison Of Football-Related Head Impacts Among Ovine, Human, And Hybrid Iii Headforms, Madysn D. Cardinal

All Dissertations

Concussions and traumatic brain injury (TBI) remains a significant public health concern, especially in American football, where repeated head impacts pose long-term risks to athlete health. While current helmet testing standards rely heavily on the Hybrid III surrogate headform to evaluate protective performance, these surrogate models lack anatomical accuracy and exclude the presence of a brain component, limiting their ability to capture the true mechanics of concussion. To address this limitation, this research developed and validated a novel inverted impact testing method that allows the impact testing of a Hybrid III headform and a cadaveric specimen. Additionally, this fixture preserves …

Robustness Investigation, Detection, And Defense Of Deep Learning Models Against False Data Injection, Amirhossein Nazeri

All Dissertations

This dissertation addresses the critical challenge of adversarial robustness in deep learning systems, focusing on two fundamental domains: time-series prediction and object detection. As these AI systems become increasingly deployed in safety-critical applications from power grid management to autonomous vehicles their vulnerability to adversarial attacks poses significant risks to infrastructure and human safety.

The first contribution introduces a novel stealthy black-box False Data Injection (FDI) attack specifically designed for quasi-periodic time-series data. Unlike existing attacks that produce easily detectable anomalies, our method generates adversarial perturbations that preserve the underlying periodicity and statistical properties of the data, effectively bypassing traditional anomaly …

Discovery Of High-Performance Cathode Materials For Protonic Ceramic Fuel Cells, Liang Han

All Dissertations

Environmental pollution and rapid energy consumption have become common problems in global development and will continue to grow with the world population. PCFCs use proton-conducting ceramics as electrolytes, with low activation energy and high ionic conductivity at intermediate temperatures, enabling them to operate at intermediate-temperature conditions, which can effectively solve the problems of poor stability and high cost of exotic materials of traditional solid oxide fuel cells. However, as the operating temperature decreases, the electrocatalytic activity of the cathode decreases significantly, seriously affecting PCFC’s performance. Therefore, developing high-performance cathode material suitable for working under intermediate-temperature conditions has become the key …

Secure Control And Trust Evaluation Framework For Autonomous Transportation Systems, Grace Muriithi

All Dissertations

This dissertation advances the cybersecurity of hybrid tracked vehicles (HTVs) and ship power systems (SPSs) by developing innovative cyber-attack models and corresponding defence frameworks. First, we formulate stealthy false-data-injection attacks (FDIAs) on HTV energy-management systems as a partially observable Markov decision process (POMDP) solved via deep reinforcement learning. A novel sniffing-based reward function guides the attacker to covertly degrade battery capacity and energy efficiency, which we evaluate using custom stealth–impact metrics and a sliding-window anomaly detector (Isolation Forest with Dynamic Time Warping). Additionally, we model sophisticated control-layer attacks in HTVs, including reinforcement-learning-optimised replay attacks and denial-of-service (DoS) attacks targeting generator-speed …

Understanding The Elements Of Sterile Processing Workflow: Or, Sterilization And Personnel, Sayed Rezwanul Islam

All Dissertations

The Sterile Processing Department (SPD), also known as the Central Sterile Services Department (CSSD), is an essential part of hospitals and healthcare facilities and is responsible for ensuring the cleanliness, sterility, and proper functioning of medical instruments. Sterile processing departments (SPDs) are key drivers of productivity, effectiveness, safety, and infection control in hospitals. A well-designed SPD workflow can enhance patient safety, reduce operating room (OR) delays, and improve productivity. To understand the flow of sterile processing and interactions between the OR and SPD, process maps and task analyses were developed through direct observations of the basic SPD functions: decontamination, assembly, …

Breeding Biofortified Protein Rich Organic Pulses For Better Human Health, Sonia Salaria

All Dissertations

Pulse crops are dry grains of legumes, the second most consumed plant crops in the world after cereals. These crops are one of the primary sources of plant-based protein and contain high concentrations of pre-biotic carbohydrates, minerals and vitamins. Recognizing the health benefits of pulses intake, their demands as sustainable food and changes in people’s diet preferences for plant-based protein have increased awareness for pulses consumption. With this scenario, improving the nutritional profile of pulse crops for rich nutrition has been an opportunity for breeders to explore and tailor the available germplasm to develop nutrient dense pulses. Furthermore, the genomic …

Data-Driven Koopman Theory For Transient Stability And Safety Analysis Of Power Systems With Renewable Penetration, Bhagyashree Umathe

All Dissertations

This dissertation presents a novel approach to analyzing and controlling nonlinear systems using the Koopman operator framework and data-driven methods. Nonlinear power systems, characterized by complex behaviors and sensitivity to initial conditions, pose significant challenges for stability and safety assessment, especially during transient events.

The first part of this work focuses on reachability analysis using the spectral properties of the Koopman operator. By leveraging eigenfunctions extracted from sampled trajectory data, the approach computes forward and backward reachable sets efficiently, even in high-dimensional nonlinear systems, without requiring dense state-space sampling. This method is validated through numerical examples, demonstrating its ability to …

Pre-Service Teacher Perceptions Of An Outdoor Learning Experience Within A Science Methods Course, Steph Dean, Summer Landreth

Publications

Given the challenges currently facing early childhood science education, this exploratory study investigates the advantages of outdoor learning as part of a teacher preparation program. A group of 49 pre-service early childhood education teachers participated in a day-long outdoor learning experience embedded within their science methods course. Guided by the theoretical lens of embodied cognition, we employed a case study approach to collect and analyze qualitative survey data, using both categorizing and connecting strategies to explore participants’ experiences. The findings reveal four key themes related to pre-service teacher perceptions, in that outdoor learning: (1) represented an engaging experience, (2) contributed …

Data-Driven Stochastic Programming For Disaster Housing Logistics Planning, Sheng-Yin Chen

All Dissertations

This dissertation develops an integrated modeling and solution framework for direct temporary disaster housing logistics under demand uncertainty. The proposed framework addresses the problem from short-term, long-term, and computational perspectives. First, a two-stage chance-constrained stochastic programming (TSCC) model is developed for short-term housing logistic planning, with demand scenarios generated via a data-driven spatial regression model that captures the relationship between housing demand, hazard exposure, and socioeconomic factors. A case study based on Hurricane Ian demonstrates that the TSCC model outperforms deterministic and traditional scenario-based models in both solution quality and robustness. Second, to address long-term housing logistics planning, a multi-horizon …

Crevice Corrosion Mechanisms Of Cocrmo Alloys In Orthopedic Implants: Retrieval Analysis, Nano-Tribocorrosion And Cellular Responses, Hwaran Lee

All Dissertations

Mechanically assisted corrosion and non-mechanically (chemically) driven corrosion in modular junctions of orthopedic implants using cobalt-chromium-molybdenum (CoCrMo) alloys remain clinical concerns and may contribute to implant failure. The underlying corrosion mechanisms are not yet fully understood, leaving a critical research gap. We hypothesized that corrosion in modular junctions may be driven by aggressive local environments, including fretting, metal ion release (cobalt ion, Co²⁺), low pH and reactive oxygen species (ROS). This dissertation aims to (1) analyze corrosion modes and potential causes in modular junctions; (2) identify chemically driven corrosion modes on CoCrMo alloys using simulated inflammatory modular taper …

Self-Poled P(Vdf-Trfe) Based Composites For Energy Harvesting And Wearable Sensor Applications, Lavanya Muthusamy

All Dissertations

The growing demand for flexible, low-power, and self-powered wearable electronic systems has accelerated research interest in polymer-based sensors and energy harvesting technologies. Among piezoelectric polymer materials, Poly(vinylidene fluoride-trifluoro ethylene) [P(VDF-TrFE)], over the years, has garnered significant attention due to its unique piezoelectric properties, high dielectric constant, mechanical flexibility, thermal stability, chemical resistance, biocompatibility and compatibility with scalable fabrication processes. Despite its advantages, conventional P(VDF-TrFE)-based devices often require external poling and face limitations in integration with low-cost, flexible substrates. To overcome these limitations, this research study explores the nanofiller approach, along with facile fabrication processes, and structural design strategies aimed at …

Computational Study Of Nonlinear Electrokinetic Phenomena In Shear-Thinning Fluids, Wai Yuen Leung

All Theses

Electrokinetic phenomena have been widely used for fluid pumping and particle manipulation in micro/nanofluidic systems. They refer to the motion of fluids or particles in response to an electric field because of the spontaneous formation of an electric double layer at the fluid-solid interface. Understanding electrokinetic phenomena in micro/nanochannels is critical for a wide range of applications across various engineering fields, such as disease diagnostics, contaminant treatment and cell analysis. To date, numerous studies have been reported on electrokinetic phenomena in Newtonian fluids, where the classical Helmholtz-Smoluchowski theory indicates a linear relationship between fluid electroosmosis/particle electrophoresis and electric field. However, …

Life Cycle Assessment Of The Cultivation Of Lettuce In A Hydroponic System Using The Nutrient Film Technique, Raquel Jordan

All Theses

Hydroponic systems are an emerging method of soilless crop cultivation typically done inside a greenhouse where nutrients are delivered dissolved in water rather than being supplied from the soil. Potential benefits of hydroponic systems include reduced irrigation requirements, higher crop yield per area, and the ability to grow crops year-round in nontraditional areas such as urban settings, cold climates, and sites with contaminated soil. However, hydroponic systems tend to have high energy requirements for lighting and climate control, which can yield significant environmental impacts. To explore the environmental impacts of cultivating lettuce in a nutrient film technique (NFT) hydroponic system, …