Digital Commons Network^™

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

All Theses

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 …

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

All Theses

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 …

Thermal Energy Storage Using High Temperature Borehole Heat Exchangers In Unconsolidated Materials, Kayla Bicknell

All Theses

Thermal energy storage is a potential method for storing excess energy produced when supply is greater than demand. The use of the subsurface for storing thermal energy has become more recognized as a viable alternative to conventional methods of energy storage. However, high temperature borehole thermal energy storage has yet to be researched in-depth. Therefore, the goal of this project is to determine the feasibility of using the subsurface to store thermal energy at relatively high temperatures.

The focus of this work is to determine what design elements would make a borehole thermal energy storage system most effective and produce …

Work-Life Coexistence In The Age Of Gen Z: A Comprehensive Examination Of Expectations And Industry Realities, Ameenullah Amiri

All Theses

The construction industry in the United States is currently facing significant workforce shortages. This issue is compounded by several challenges, including the slower hiring pace of younger generations compared to the retirement of baby boomers. Generation Z (Gen Z) has shown less interest in joining the construction industry, exacerbating the problem. A systematic literature review was conducted toa identify overlaps and gaps between the current construction industry workforce's perceptions of the industry and preferences of Gen Z. Based on the literature review, work-life balance or “Work-life Coexistence (WLC)" was identified as the most preferred factor for Gen Z. The traditional …

Germination Trends Of American Chaffseed, Schwalbea Americana L., And Factors Affecting First-Year Seedling Development, Trenton Miller

All Theses

Following centuries of exploitation and fire suppression, longleaf pine systems are now the focus of many conservation efforts. Efforts to restore populations of Schwalbea americana L. in longleaf pine savannas have been met with frustratingly low recruitment. While past studies have briefly quantified germination rates for Schwalbea, there have not been any studies yet that truly investigate this plant’s germination requirements. Additionally, there has been little research into characterizing the parasitic relationship between Schwalbea and its various host species. We conducted a germination study in a growth chamber that investigated Schwalbea’s germination rate and time to germinates as …

Converging Human Intelligence With Ai Systems To Advance Flood Evacuation Decision Making, Rishav Karanjit

All Theses

The powers that artificial intelligence (AI) has developed are astounding, with recent success in integrating into a human cognitive workflow. AI will attain its full potential only if, as part of its intelligence, it also actively teams up with humans to co-create solutions. Combining AI simulation with human understanding and strategic abilities through data convergence may optimize the process and provide a capacity akin to "teaming intelligence." This thesis will introduce the concepts of Human AI Convergence (HAC) capabilities for flood evacuation decision-making. The concept introduced in this thesis is the first step toward the HAC concept in weather disaster …

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

All Theses

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 …

Experimental Study On The Impact Of Low Thermal Inertia Thermal Barrier Coatings On Ppci-Diffusion Gci Combustion, Kunal Vedpathak

All Theses

The application of thermal barrier coatings (TBCs) has been studied in homogenous charge compression ignition (HCCI), conventional diesel combustion (CDC), and spark ignition (SI). Gasoline compression ignition (GCI) combines the low soot and NOx emissions of HCCI with combustion controllability through fuel stratification. GCI has become an interesting prospect due to the reduction in gasoline consumption due to the electrification and hybridization of the light-duty sector. It can be used as a preferred combustion mode in heavy-duty engines to reduce emissions with minimal modifications. GCI exhibits better combustion efficiency than HCCI. Advances in material technology have combined low thermal conductivity …

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

All Theses

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 …

Effect Of Latex Modified Concrete Overlays With Reduced Surface Preparation On The Load Distribution And Flexural Strength Of Channel Girders, Samuel Dodd

All Theses

This thesis investigates the use of a Latex Modified Concrete (LMC) overlay to increase the strength of prestressed channel girders and enhance their ability to distribute load. The research conducted in this thesis involved material testing of several different LMC mixes and flexural testing of an LMC overlay and girder system. The material testing was used to determine a reasonable LMC mix design and surface preparation method to be used for the overlay. Based on material testing it was concluded that a rapid-set mix and pressure washing of the girder surfaces were a reasonable mix design and surface preparation for …

Safe Navigation Of Quadruped Robots Using Density Functions, Andrew Zheng

All Theses

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 …

The Generation Of A Physics Informed Machine Learning Model To Predict Defect Evolution In Materials & On The Thermally Activated Regime Of Dislocation Motion: A Simulation Driven Study On The Mechanical Behavior Of Crystals, Liam Myhill

All Theses

Line defects in crystals, known as dislocations, govern the mechanisms of plastic deformation at the micro-meso scale. The study of dislocations has proliferated the field of materials science and engineering for since the 1950’s, and modern studies show increasing utilization of computational methods to model the evolution of line defects in material systems. In keeping with modern research practice, the studies herewith demonstrate the use of advanced computing to generate models which can be used to better understand the behaviors of dislocations within crystal matrices. An advanced high-throughput model for a physically informed machine learning graph neural network (PIML-GNN) is …

Model Of Surface Waves On A Viscoelastic Material In A Cylindrical Container With Edge Constraints, Phillip Wilson

All Theses

A theoretical model is developed for the resonant frequencies and mode shapes of pinned edge surface waves on a viscoelastic fluid contained in a finite depth cylindrical container. A boundary integral approach is used to map the governing equations to the domain boundary. The surface waves obey an eigenvalue operator equation that depends on four dimensionless parameters: the cylinder aspect ratio, the Bond number, the Ohnesorge number, and the elastocapillary number. A solution is constructed using a Rayleigh-Ritz variational procedure over a constrained function space, which is able to effectively incorporate the pinned edge boundary condition. Mode shapes are defined …

An Empirical Examination Of Consequential Factors Of Negative Program Culture As Determinants Of Affective Well-Being In Graduate Students, Morgan Chandler

All Theses

There is evidence of a crisis of low affective well-being troubling graduate students nationwide. Recent studies have shown that graduate students exhibit indicators of low affective well-being, such as levels of anxiety and depression six times greater than the general population (Galleo et al., 2021; Glover, 2019), high levels of being overwhelmed (Kaler & Stebleton, 2019), and overall increased psychological distress (Hacker, 2021). The prevalence and severity of these issues indicate that their causes may exceed personal factors (Bekkouche et al., 2022). Previous research has identified the quality of culture and culture-related factors within graduate schools and programs to be …

Analysis Of Length Shortening Effect On Bistability And Curvature In A Rectangular Bistable Composite Laminate With A Rigid Tab On One End Integrated To Its Geometry, Rizwana Akter

All Theses

Bistable composite laminates gained significant attention due to their distinct feature of maintaining multiple stable equilibrium states. The phenomenon stems from thermal stress during the curing process of systematically laid-up Carbon Fiber Prepreg (CFRP), resulting in snap-through behavior with dual cylindrical shapes characterized by opposite signs and perpendicular axes of curvature. In addition to exploring the fundamental characterization of bistable behavior and equilibrium shapes, investigating the impact of boundary conditions on such laminates poses great potential. In this research, the shape-changing behavior of a cross-ply bistable laminate with varying lengths under the boundary condition of a fixed tab on one …

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

All Theses

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 …

Development Of Scope Of Services For Procurement Of Professional Consultant Services On Transportation Projects – A Study Of South Carolina Department Of Transportation, Ajay Jadhav

All Dissertations

Project Scoping Process (PSP) is one of the significant steps that starts at the very beginning of the project life cycle. During project initiation phase, project scoping is kicked off which includes documenting a list of project-specific goals, deliverables, tasks, costs, and deadlines. The scoping phase duration depends on the project complexity and involves various stakeholders, establishing team, confirming the project purpose and need, initiating the environmental revie process, determining the level of environmental documentation and permit requirements, conducting survey, identifying project risks and tools to mitigate them, and evaluating public involvement strategies. A well-defined PSP is therefore essential for …

Controlled Manipulation And Transport By Microswimmers In Stokes Flows, Jake Buzhardt

All Dissertations

Remotely actuated microscale swimming robots have the potential to revolutionize many aspects of biomedicine. However, for the longterm goals of this field of research to be achievable, it is necessary to develop modelling, simulation, and control strategies which effectively and efficiently account for not only the motion of individual swimmers, but also the complex interactions of such swimmers with their environment including other nearby swimmers, boundaries, other cargo and passive particles, and the fluid medium itself. The aim of this thesis is to study these problems in simulation from the perspective of controls and dynamical systems, with a particular focus …

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

All Dissertations

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

All Dissertations

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 …

Exploring Critical Media Literacies In Youth Media Production: Tackling Falsehoods Through Media Creation, Oluwadara Abimbade

All Dissertations

This Mixed Method Research (MMR) study, using a convergent parallel design, explores the practices of middle school students as creators and consumers of false information-free media. It investigates their ability to identify falsehoods, explores the impact of false information on various aspects of their lives, and introduces an innovative media production boot camp to foster awareness, detection, and prevention of false information dissemination in their media creations. The research, conducted with six participants, employs a combination of qualitative and quantitative data collection methods, including video and in-person observations, interviews, surveys, and artifacts. Integrating quantitative and qualitative data enables a comprehensive …

Clemson University Board Of Trustees, Special Board Meeting, 2023 December 1, Clemson University Board Of Trustees

Minutes

No abstract provided.

Finite Element Analysis On Laser Sintering Of Ceramic Materials, Shardul Sharma

All Theses

Laser sintering of ceramics plays a vital role in advanced additive manufacturing due to its precise fabrication of complex ceramic structures, localized heating and microstructural control. It allows the production of complex and customized ceramic parts for applications such as the aerospace industry and biomedical devices. However, due to the high thermal gradients produced during the process, laser sintering technology faces fundamental challenges, such as thermal stresses and crack formation. Establishing a valid numerical model to guide the ceramic laser sintering process, which predicts the thermal and mechanical behavior of the component, is necessary.

In this work, the modified Skorohod-Olevsky …

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

All Dissertations

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 …

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

All Dissertations

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

All Dissertations

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 …

From Experiences To Beliefs: An Exploratory Case Study On Science Teachers’ Attitudes Towards Emergent Bilinguals, Yamil Ernesto Ruiz

All Dissertations

Emergent bilingual (EB) students in the US are those who are in the process of developing academic English proficiency. EBs are some of the fastest growing populations of students in American public schools. There exists a great deal of research geared towards developing both curricular resources and instructional strategies to best support EBs in the science classroom, however many of these professional development studies lament the lack of growth in terms of achievement in science learning outcomes of EBs. It is possible that due to a lack of transformation in their beliefs that the teachers in these studies do not …

Interpretable Mechanistic And Machine Learning Models For Pre-Dicting Cardiac Remodeling From Biochemical And Biomechanical Features, Anamul Haque

All Dissertations

Biochemical and biomechanical signals drive cardiac remodeling, resulting in altered heart physiology and the precursor for several cardiac diseases, the leading cause of death for most racial groups in the USA. Reversing cardiac remodeling requires medication and device-assisted treatment such as Cardiac Resynchronization Therapy (CRT), but current interventions produce highly variable responses from patient to patient. Mechanistic modeling and Machine learning (ML) approaches have the functionality to aid diagnosis and therapy selection using various input features. Moreover, 'Interpretable' machine learning methods have helped make machine learning models fairer and more suited for clinical application. The overarching objective of this doctoral …

Studies On Electrochemical Hydrogen Isotope Separation, Liyanage Mayura Sankalpa Silva

All Dissertations

Graphene-integrated Proton Exchange Membrane (PEM) electrochemical cells have emerged as a novel area of scientific investigation in the realm of hydrogen isotope separation. Chemical Vapor Deposited (CVD) graphene has been especially useful due to its large-scale production capability for scaling-up purposes. The research described in this dissertation explores the role that inadvertent introduction of cations, notably ammonium and copper, during the CVD graphene transfer onto PEM substrates, such as Nafion, might play in affecting hydrogen ion transport and isotope separation in PEM electrochemical cells. An extensive review of existing literature exposed a gap concerning unintentional cation introductions during graphene transfer, …