Femtosecond Laser Shock Peening And The Dynamics Of Femtosecond Laser-Induced Shock Waves, Yuxin Li

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Laser shock peening (LSP) is an important material surface strengthening technique that uses laserinduced shock waves to cause severe plastic deformation near material surfaces. It can significantly improve material properties like hardness, strength, fatigue life, and corrosion resistance and is widely used in industrial sectors such as automotive, aerospace, nuclear, and medical areas. The conventional nanosecond laser shock peening (ns-LSP) has demonstrated effectiveness but faces challenges such as complex setup, low throughput, high energy consumption, and inflexibility for complex geometries. Femtosecond laser shock peening (fs-LSP) offers a promising alternative to overcome these issues, thanks to its ultra-high laser intensity and …

Impacts Of Connected And Automated Vehicles On Energy And Traffic Flow: Optimal Control Design And Verification Through Field Testing, Tyler Ard

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This dissertation assesses eco-driving effectiveness in several key traffic scenarios that include passenger vehicle transportation in highway driving and urban driving that also includes interactions with traffic signals, as well as heavy-duty line-haul truck transportation in highway driving with significant road grade. These studies are accomplished through both traffic microsimulation that propagates individual vehicle interactions to synthesize large-scale traffic patterns that emerge from the eco-driving strategies, and through experimentation in which real prototyped connected and automated vehicles (CAVs) are utilized to directly measure energy benefits from the designed eco-driving control strategies. In particular, vehicle-in-the-loop is leveraged for the CAVs driven …

Deep Reinforcement Learning For The Design Of Structural Topologies, Nathan Brown

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Advances in machine learning algorithms and increased computational efficiencies have given engineers new capabilities and tools for engineering design. The presented work investigates using deep reinforcement learning (DRL), a subset of deep machine learning that teaches an agent to complete a task through accumulating experiences in an interactive environment, to design 2D structural topologies. Three unique structural topology design problems are investigated to validate DRL as a practical design automation tool to produce high-performing designs in structural topology domains.

The first design problem attempts to find a gradient-free alternative to solving the compliance minimization topology optimization problem. In the proposed …

1-Methyl-4-Phenyl-1,2,3,6-Tetrahydropyridine (Mptp)-Treated Adult Zebrafish As A Model For Parkinson’S Disease, Emmeline Bagwell

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The use of adult zebrafish, Danio rerio, as a model for human neurodegenerative diseases has proven valuable in pharmaceutical development and genetic disease research due to their high genetic homology to humans, cost-effective husbandry, and quick life cycle breeding times. Despite their promise, most zebrafish research has focused on embryonic stage organisms, primarily due to the ease of direct handling protocols and rapid progression through developmental stages. Recognizing the limitations of early-stage organisms in modeling adult diseases, recent efforts have shifted the applicability of zebrafish models, particularly for Parkinson's Disease, due to the nature of the disease impacting patients 55 …

Enhancing Peanut Harvesting: Evaluating Factors That Influence Yield And Developing A Web-Based Field Drying Forecast Tool, Charles Burkett

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Peanuts have one of the largest economic impacts of agronomic crops in the State of South Carolina. Peanut harvest operations involve several steps (digging, curing, combining) using equipment unique to peanut production, including peanut digger/shaker/inverters. This thesis evaluates several aspects of peanut harvest operations, including how precision agriculture technologies can enhance decision-making and enhance production. Several studies were conducted to analyze how various aspects of peanut harvesting operations contribute to decrease losses in yield and revenue. The first study evaluated the influence of operator experience on mean absolute guidance line deviation during peanut digging operations and the associated effects on …

Barriers To Integrating Magnetic Resonance Imaging Systems In Emergency Medical Service Ambulances For Stroke Care, Arvind Kolangarakath

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Stroke is a life-threatening condition that can cause permanent damage by stopping blood flow in the brain. Quick and precise intervention is imperative, as every second lost increases tissue deterioration and impacts patient outcomes. Several technological advancements such as Magnetic Resonance Imaging (MRI), have revolutionized stroke care by enabling more accurate and quicker diagnoses in hospitals. Portable head MRI scanners with lower magnetic fields are a recent innovation capable of providing neuroimaging at the point of care within hospital settings. Integrating such a device into ambulances could potentially enhance stroke care during transit, facilitating prompt diagnosis and prognosis. However, few …

Creation And Validation Of A Novel Bayesian Calibration Method With Griddy Gibbs Sampling, Hannah Stewart

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Computer models of physical systems are widely used in lieu of, or in tandem with, experimental testing. It is critical to verify the accuracy of computer models through the process of calibration. Typical calibration methods are often computationally expensive and therefore cannot be performed in real time. This thesis presents a novel Bayesian calibration method using a Griddy Gibbs sampling algorithm to improve calibration speeds. This method was verified in two applications: a location-dependent dataset in the heat transfer analysis of an engine piston, and time-dependent tire forces in a drum test. The proposed method was directly compared to a …

Detection Of Myofascial Trigger Points With Ultrasound Imaging And Machine Learning, Benjamin Formby

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Myofascial Pain Syndrome (MPS) is a common chronic muscle pain disorder that affects a large portion of the global population, seen in 85-93% of patients in specialty pain clinics [10]. MPS is characterized by hard, palpable nodules caused by a stiffened taut band of muscle fibers. These nodules are referred to as Myofascial Trigger Points (MTrPs) and can be classified by two states: active MTrPs (A-MTrPs) and latent MtrPs (L-MTrPs). Treatment for MPS involves massage therapy, acupuncture, and injections or painkillers. Given the subjectivity of patient pain quantification, MPS can often lead to mistreatment or drug misuse. A deterministic way …

Cyber-Threat Detection Strategies Governed By An Observer And A Neural-Network For An Autonomous Electric Vehicle, Douglas Scruggs

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A pathway to prevalence for autonomous electrified transportation is reliant upon accurate and reliable information in the vehicle’s sensor data. This thesis provides insight as to the effective cyber-attack placements on an autonomous electric vehicle’s lateral stability control system (LSCS). Here, Data Integrity Attacks, Replay Attacks, and Denial-of-Service attacks are placed on the sensor data describing the vehicle’s actual yaw-rate and sideslip angle. In this study, there are three different forms of detection methods. These detection methods utilize a residual metric that incorporate sensor data, a state-space observer, and a Neural-Network. The vehicle at hand is a four-motor drive autonomous …

Custom-Designed And Collaborative Unmanned Systems With Learning-Based Applications, Robert Zanone

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This paper presents a culmination of work utilizing custom-designed autonomous vehicles and learning based simulations applied to real world applications across three distinct research domains. The first focuses on deploying autonomous drones in an agricultural setting for plant phenotyping. A telescoping arm is used to deploy a camera into the plant foilage for under-the-canopy imaging. The system utilizes on-board image processing to identify early-stage issues such as diseases, bacteria, and pests in crop plants to provide data for crop loss mitigation. The system takes advantage of the maneuverability of drones allowing for quick random sampling when traversing large areas.

In …

Material World, Nicole Weldy

All Theses

My thesis, Material World, delves into the use of the crochet unit as a construction technique for building forms. Through this, I aim to organize different materials in a way that responds to the challenges posed by the physical world. My artistic process is centered around honoring the inherent qualities of thread and uses these qualities to create form, lightness, and linearity. At the same time, I remain receptive to transformative processes such as combining three-dimensional (3D) printed lines and lace stiffener to push the boundaries of what thread can do. By combining manual craftsmanship with technology materialized as …

Safe Navigation Of Quadruped Robots Using Density Functions, Andrew Zheng

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Safe navigation of mission-critical systems is of utmost importance in many modern autonomous applications. Over the past decades, the approach to the problem has consisted of using probabilistic methods, such as sample-based planners, to generate feasible, safe solutions to the navigation problem. However, these methods use iterative safety checks to guarantee the safety of the system, which can become quite complex. The navigation problem can also be solved in feedback form using potential field methods. Navigation function, a class of potential field methods, is an analytical control design to give almost everywhere convergence properties, but under certain topological constraints and …

Development Of A User-Friendly Shelf-Life Model To Evaluate The Suitability Of Sustainable Materials In Roasted And Ground Coffee Fractional Packs, Matthew Baxley

All Theses

Roasted and ground coffee is a shelf stable product yet quite sensitive to oxidative staling. A consumer acceptance-based shelf-life modeling system was proposed with intent for the rapid determination of suitable coffee packages. This model requires as input the oxygen consumption rate (OCR) of the coffee, barrier values of packages, and the size of the packaging. Within the time period tested, it was shown that this model accurately predicted the oxygen uptake of coffee over time. Four bio-based packaging systems with barrier layers including mPLA, mPE, mcellophane, and paper were compared against a control (mPET). These materials displayed a range …

Experimental Investigation Of Low Thermal Inertia Thermal Barrier Coatings For Spark Ignition Engines, John Gandolfo

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The application of thermal barrier coatings (TBCs) in spark ignition (SI) engines has historically been avoided due to the knock penalty associated with higher surface temperatures induced by the ceramic layer. However, advances in low thermal inertia coatings (i.e., temperature swing coatings) that combine low thermal conductivity with low volumetric heat capacity can prevent excessively high surface temperatures during the intake stroke and reduce or avoid knock while improving performance and efficiency. This thesis experimentally evaluates the effectiveness of these low thermal inertia coatings in a single-cylinder research engine representative of modern SI engines.

First, four pistons coated with a …

Medical Simulation-Based Sensor Methods For Ultrasound-Guided Dialysis Cannulation Skill Assessment, Devansh Shukla

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End-stage kidney disease (EKSD) is the final, permanent stage of chronic kidney disease (CKD), where the body's kidneys cannot filter blood sufficiently. Hemodialysis treats ESKD by filtering wastes and water from your blood externally via a dialyzer. Patients on hemodialysis require a vascular access, typically an arteriovenous fistula (AVF) or arteriovenous graft (AVG) for dialysis, which is used three times a week for about four hours a session. These life-saving therapies can be quite tedious, especially for elderly patients and patients with co-morbidities. As such, successful cannulation is extremely important to ensure the longevity of the patient's vascular access and …

Assessing Chondrocyte Viability Of Articular Cartilage Using Label-Free Imaging Methods, Hongming Fan

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ABSTRACT

Articular cartilage covers the ends of bones, providing a protective layer that can endure forces during movement. Chondrocytes, the only cell type found in articular cartilage, produce collagen fibers and proteoglycans that maintain the extracellular matrix (ECM). Cartilage damage impairs chondrocytes and their ability to maintain tissue stability. There are various factors that can cause cell death, which can be broadly classified into two categories: programmed cell death (apoptosis) and non-programmed cell death (necrosis). The consequences of cell death can have significant impacts on the extracellular matrix (ECM). The ECM is a complex network of proteins and carbohydrates that …

An In Vitro Platform To Characterize Myocardial Wound Remodeling, Jonathan Heywood

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Heart Failure, sometimes called Congestive Heart Failure, is a collection of pathological disruptions in which the heart is unable to pump blood properly. It affects over 6 million people in the United States, with the cost-per-patient at approximately $30,000 and the total cost estimated to be $160 billion by 2030. There is no single cause of heart failure, as it can manifest as a varying array of diseases, disorders, and syndromes. However, many of these underlying diseases result specifically from dysregulation of mechanically active cells called cardiac fibroblasts, which play a critical role in the remodeling of the extracellular matrix …

Model-Free Methods To Analyze Pmu Data In Real-Time For Situational Awareness And Stability Monitoring, Sean Kantra

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This dissertation presents and evaluates model-free methodologies to process Phasor Measurement Unit (PMU) data. Model-based PMU applications require knowledge of the system topology, most frequently the system admittance matrix. For large systems, the admittance matrix, or other system parameters, can be time-consuming to integrate into supporting PMU applications. These data sources are often sensitive and can require permissions to access, delaying the implementation of model-based approaches. This dissertation focuses on evaluating individual model-free applications to efficiently perform functions of interest to system operators for real-time situational awareness. Real-time situational awareness is evaluated with respect to central digitization where the PMU …

Physics-Based Machine Learning Methods For Control And Sensing In Fish-Like Robots, Colin Rodwell

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Underwater robots are important for the construction and maintenance of underwater infrastructure, underwater resource extraction, and defense. However, they currently fall far behind biological swimmers such as fish in agility, efficiency, and sensing capabilities. As a result, mimicking the capabilities of biological swimmers has become an area of significant research interest. In this work, we focus specifically on improving the control and sensing capabilities of fish-like robots.

Our control work focuses on using the Chaplygin sleigh, a two-dimensional nonholonomic system which has been used to model fish-like swimming, as part of a curriculum to train a reinforcement learning agent to …

Structural Characterization Of Cardiomyocyte Microenvironment In Murine Myocardium By Multimodal Stimulated Emission Depletion Microscopy, Zhao Zhang

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Cardiomyopathy, a disease of the heart muscle, is characterized by structural and functional abnormalities of the myocardium, in the absence of coronary artery disease, hypertension, valvular disease or congenital heart disease. In 2020, there were approximately 6.11 million prevalent cases of cardiomyopathy and myocarditis, and 0.37 million related deaths worldwide. Many affected individuals are asymptomatic, and chronically treated patients are at risk of heart failure. Within the myocardium, cardiomyocytes reside in a complex and dynamic extracellular matrix (ECM), consisting of basement membrane and interstitial matrix. The interactions between cardiomyocytes and myocardial ECM play a critical role in maintaining cardiac geometry …

Feasibility Of Using High-Alkali Natural Pozzolans And Reclaimed Fly Ash As Alternative Supplementary Cementitious Materials In Concrete, Weiqi Wang

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Due to the shortage of supplementary cementitious materials (SCMs) in the concrete industry, it is necessary to seek a new alternative. This study evaluates the feasibility of high-alkali SCMs, which were not recommended previously due to potentially exacerbating alkali-silica reaction (ASR) in concrete. The study addresses theSCMs’ ASR mitigation performance, evaluated by ASTM C1567, C1293, and AASHTO T380. Other concrete durability tests, including ASTM C596 drying shrinkage test, ASTM C1012 sulfate resistance test, and ASTM C1202 rapid chloride ions penetration test, were also conducted in this study. The ASTM C311 strength activity index test, thermal gravimetric analysis (TGA), and ASTM …

Ti-6al-4v Β Phase Selective Dissolution: In Vitro Mechanism And Prediction, Michael A Kurtz

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Retrieval studies document Ti-6Al-4V β phase dissolution within total hip replacement systems. A gap persists in our mechanistic understanding and existing standards fail to reproduce this damage. This thesis aims to (1) elucidate the Ti-6Al-4V selective dissolution mechanism as functions of solution chemistry, electrode potential and temperature; (2) investigate the effects of adverse electrochemical conditions on additively manufactured (AM) titanium alloys and (3) apply machine learning to predict the Ti-6Al-4V dissolution state. We hypothesized that (1) cathodic activation and inflammatory species (H₂O₂) would degrade the Ti-6Al-4V oxide, promoting dissolution; (2) AM Ti-6Al-4V selective dissolution would occur …

A Digital Triplet For Utilizing Offline Environments To Train Condition Monitoring Systems For Rolling Element Bearings, Ethan Wescoat

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Manufacturing competitiveness is related to making a quality product while incurring the lowest costs. Unexpected downtime caused by equipment failure negatively impacts manufacturing competitiveness due to the ensuing defects and delays caused by the downtime. Manufacturers have adopted condition monitoring (CM) techniques to reduce unexpected downtime to augment maintenance strategies. The CM adoption has transitioned maintenance from Breakdown Maintenance (BM) to Condition-Based Maintenance (CbM) to anticipate impending failures and provide maintenance actions before equipment failure. CbM is the umbrella term for maintenance strategies that use condition monitoring techniques such as Preventive Maintenance (PM) and Predictive Maintenance (PdM). Preventive Maintenance involves …

Atomistic And Mesoscale Modeling Of Microstructure Development During Solid-State Sintering, Omar Marwan Isa Hussein

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Interfaces are ubiquitous in materials systems, and they influence the processing and properties of nearly all engineering and functional materials. Examples include grain boundaries (GBs) in polycrystalline materials, free surfaces in nanoparticles, and phase boundaries in multiphase materials. Therefore, understanding and controlling interfacial processes is a key aspect of materials design and discovery efforts. Recent developments in advanced manufacturing and synthesis techniques have enabled the fabrication of materials architectures with intricate nanoscale features. Of particular interest is solid-state sintering, known for creating complex and high-precision geometries with controlled microstructures. While sintering science has been the subject of active research, very …

Improving Hexapod Platform Pose Accuracy - A Photogrammetry-Based Approach, Sourabh Karmakar

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The aim of this research is to make a newly constructed Stewart-Gough Platform-based test frame Tiger 66.1 operational by developing control software and estimating the error in its pose accuracy. The accuracy of the platform is affected by one source or multiple sources. The typical error sources are kinematic and structural, some of them originate from manufacturing imperfections, assembly deviations, elastic deformations, thermal deformations, and joint clearances which change the expected kinematic behavior of the manipulator. Also, some non-mechanical errors like transmission error, sensor accuracy, algorithm error, and truncation error in calculation contribute significantly in some cases. Using pose deviations …

Atomistic And Mesoscale Modeling Of Microstructure Development During Solid-State Sintering, Omar Hussein

All Dissertations

Interfaces are ubiquitous in materials systems, and they influence the processing and properties of nearly all engineering and functional materials. Examples include grain boundaries (GBs) in polycrystalline materials, free surfaces in nanoparticles, and phase boundaries in multiphase materials. Therefore, understanding and controlling interfacial processes is a key aspect of materials design and discovery efforts.

Recent developments in advanced manufacturing and synthesis techniques have enabled the fabrication of materials architectures with intricate nanoscale features. Of particular interest is solid-state sintering, known for creating complex and high-precision geometries with controlled microstructures. While sintering science has been the subject of active research, very …

Exploring Modalities Of Productivity And Critical Quality Attributes In Fed-Batch Chinese Hamster Ovary Cell Cultures, Stephanie Klaubert

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Chinese hamster ovary (CHO) cells are among the most commonly used mammalian cell lines for the production of recombinant therapeutic proteins due to ease of culturing and humanlike post-translational modification capabilities. However, when compared to microbial systems, CHO cell line growth and productivity is relatively low. As the demand for monoclonal antibody (mAb) treatments continues to rise, it is critical to explore modalities for improved growth and productivity in CHO cell cultures, with the goal of increased protein concentrations and maintained product quality. Though some mechanisms for improved productivity, including temperature and cell culture media formulations, are relatively well understood; …

Towards Enabling Usable Batteryless Wearables, Arwa Alsubhi

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Wearable devices have become ubiquitous in modern technology, providing a convenient way for a large number of users to monitor their health and track their daily activities. However, despite their numerous benefits, wearable devices are not without their challenges. One of the most significant issues is the need to recharge their batteries, which can disrupt users’ daily routines and might result in the discontinuation of device use.

Replacing batteries with capacitors and charging them using the available harvested energy from the surrounding environment (e.g., kinetic, thermal, or solar energy) eliminates the burden of recharging or replacing batteries, resulting in convenient, …

Engineering Next-Generation Cardiovascular Therapies, Ryan Walker Barrs

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Cardiovascular diseases are the leading cause of death worldwide. Heart disease, in particular, accounted for 1 in every 5 deaths in the United States in 2021, representing a substantial public health burden that will require more effective treatment options to alleviate. Heart transplant surgery is currently the only option to completely restore cardiac function, but many patients die while waiting for a transplant due to a longstanding organ donor shortage. Thus, there is a dire need for accessible treatment options that can repair damaged hearts. Recent advances in tissue engineering and regenerative medicine have accelerated the development of therapies for …

Improving Sizing Resolution Of Particle Impactors In The Nanoparticle Range, Shivuday Kala

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The application of particle size measurement extends across many fields: air quality measurement, pharmaceutical studies, paint and coating production, and nanoparticle formulation to name a few. Therefore, accurate measurement of nanoparticles is critical to aerosol science. While devices currently exist that can size and count nanoparticles such as electrical mobility spectrometers, dynamic light scattering devices, and small angle X-ray scattering devices, their high costs, complex operation, and lack of outdoor usability, restrict their use in practical applications. Among the devices that can size aerosols down to the nanoscale, cascade impactors stand out because of their robustness, relatively simple design, low …