Digital Commons Network^™

Effect Of Chlorine Dioxide Gas On The Properties Of Packaging Materials And Effect Of Chlorine Dioxide Gas To Maintain The Quality Of Fresh Strawberries, Duleeka Kuruwita, Duleeka Prasadani Kuruwita Arachchige

All Dissertations

ClO₂ as an antimicrobial gas in the headspace of produce package is a relatively novel approach. Gaseous ClO₂ is more effective than aqueous ClO₂ and can be used in the headspace of fresh food packages. ClO₂ gas can diffuse into product surfaces and films. As an oxidizer, it can react with and change polymeric package components, possibly affecting the product’s shelflife.

This research studied effects of ClO₂ gas treatments on produce packaging materials (APET, two PE types, Nylon). The treatment group (with ClO₂) and the control group (without ClO₂) of packaging …

Design, Fabrication, And Characterization Of Conjugated Polymeric Electrochemical Memristors As Neuromorphic/Integrated Circuits, Benjamin Grant

All Dissertations

Organic materials are promising candidates for future electronic devices compared to the complementing inorganic materials due to their ease of processability, use, and disposal, low cost of fabrication, energy efficiency, and flexible nature toward implementation as flexible and non-conformal devices.With that in mind, electrochemical materials have been widely demonstrated with commercial use as sensors, displays, and a variety of other electronic devices. As Moore's law predicts the increase in the density of transistors on a chip, the requirement to create either smaller transistors or the replacement of the transistor device entirely is apparent. Memory resistors, coined ``memristor", are variable resistive …

Carbon Fibers From Bio-Based Precursors Derived From Renewable Sources, Sagar Kanhere

All Dissertations

Carbon fibers have the highest strength and modulus among all known fibers and are used as reinforcements in high-performance composites [1]. Carbon fibers also have a very low density relative to metals. Therefore, carbon fibers possess ultrahigh specific strength and modulus, which make them desirable for high-performance light-weight composites. A vast majority of commercial carbon fibers are produced from PAN precursors that are expensive, which limits the use of PAN-derived carbon fibers to aerospace applications (e.g., airplanes). However, for costsensitive applications, there is a need for low-cost, moderate performance carbon fibers. Lignin is a low-cost by-product of pulping and biorefining …

Computational And Experimental Investigations Of Alkali Cation Interactions At The Rutile – Water Interface, Isaac Johnston

All Dissertations

Overall, the objective of this dissertation was to investigate the degree of sorption for the alkali cations on rutile to ascertain the impact of different cation properties, such as ion size and charge density, on sorption mechanics as well as probe how the ion may alter the surface – aqueous interface. Initial molecular dynamic simulations and batch experiments showed minimal surface sorption for any alkali cation at relatively low concentrations while simultaneously suggesting the enthalpy of deprotonation shifts slightly in the presence of the alkali cations at different ionic strengths. The cations are likely causing small reorientations of the near-surface …

Development Of Enzyme-Responsive Polymersomes As A Drug Delivery System For Gm1 Gangliosidosis, Bipin Chakravarthy Paruchuri

All Dissertations

GM1 gangliosidosis is a lysosomal storage disorder caused by deficiency of β-galactosidase (βgal) and subsequent accumulation of GM1 ganglioside in lysosomes. The rare nature of this disorder presents challenges with prognosis and treatment. Enzyme replacement therapy (ERT) can effectively treat systemic deficiencies, but the intravenously administered enzyme cannot cross the blood-brain barrier (BBB) to treat the central nervous system. A delivery system to encapsulate and deliver the enzyme can facilitate enzyme transport across the BBB with suitable surface modifications. One of the pathological aspects of GM1-affected cells is the upregulation of the lysosomal enzyme hexosaminidase A (HexA). In this dissertation, …

Profiling And Engineering The Unfolded Protein Response In Therapeutic Protein-Producing Cho Cell Lines, Dyllan Rives

All Dissertations

Industrial Chinese hamster ovary (CHO) production of therapeutics requires cell lines with high secretory capacity to avoid an accumulation of improperly folded proteins, or endoplasmic reticulum (ER) stress. This presents a challenging engineering bottleneck. The unfolded protein response (UPR) is initiated to overcome ER stress and reestablish homeostasis. In this dissertation, the impacts of ER stress and the UPR on protein production in mammalian cells are detailed, and both selection- and rational-based strategies for enhancing the ER stress response in productive CHO cell lines are reviewed. This project aims to expand on recent research efforts for engineering ER stress-related responses …

Uni-Prover: A Universal Automated Prover For Specificationally Rich Languages, Nicodemus Msafiri John Mbwambo

All Dissertations

Formal software verification systems must be designed to adapt to growth in the scope and complexity of software, driven by expanding capabilities of computer hardware and domain of potential usage. They must provide specification languages that are flexible and rich enough to allow software developers to write precise and comprehensible specifications for a full spectrum of object-based software components. Rich specification languages allow for arbitrary extensions to the library of mathematical theories, and critically, verification of programs with such specifications require a universal automated prover. Most existing verification systems either incorporate specification languages limited to first-order logic, which lacks the …

Multiscale Topology Optimization With A Strong Dependence On Complementary Energy, Dustin Dean Bielecki

All Dissertations

A discrete approach introduces a novel deep learning approach for generating fine resolution structures that preserve all the information from the topology optimization (TO). The proposed approach utilizes neural networks (NNs) that map the desired engineering properties to seed for determining optimized structure. This framework relies on utilizing parameters such as density and nodal deflections to predict optimized topologies. A three-stage NN framework is employed for the discrete approach to reduce computational runtime while maintaining physics constraints.

A continuous representation that uses complementary energy (CE) methods to solve a representative element's homogenized properties consists of an embedded structure that is …

In Vitro Bioreactor For Mechanical Control And Characterization Of Tissue Constructs, Samuel Coeyman

All Dissertations

Heart failure (HF) currently affects over 6 million Americans, 50% of whom die within 5 years of their initial diagnosis. A major contributor to the onset of HF is cardiac fibrosis in the myocardium, which arises when fibroblasts (FBs) are activated in response to heightened mechanical stress from overload conditions like hypertension. Activated FBs remodel the extracellular matrix (ECM) and secrete ECM proteins including collagen. FB remodeling has been studied in the past by applying forces and/or deformations to three-dimensional, cell-seeded gels and tissue constructs in vitro. Unfortunately, previous stretching platforms have traditionally not enabled mechanical property assessment to be …

Influence Of Climate And Droughts On Visibility Degradation In Saudi Arabia, Saleh Alhathloul

All Dissertations

The spatial and temporal distribution of temperature and precipitation determines the availability of water resources for ecosystems. The hydrological cycle can be disrupted by differences in meteorological variables and the random nature of water demand. Horizontal visibility degradation is an indicator of the changes in local meteorological variables, rainfall deficits, and drought conditions. Long-term analysis of meteorological variables and visibility records helps understand the causes of visibility degradation. The first objective of this dissertation is to investigate the long-term variability of horizontal visibility along with metrological variables based on annual and seasonal time scales over Saudi Arabia. The second objective …

Unveiling The Potential Of Calcium And Natamycin For Botrytis Blight Management On Cut Roses, Melissa Munoz

All Dissertations

Botrytis blight caused by the fungus Botritys cinerea is the most devastating disease of cut roses. The extensive use of fungicides used for Botrytis blight management during cut rose production and postharvest represents a severe threat in terms of fungicide resistance development as has been previously reported. Additionally, health concerns for growers and the environment are growing in recent years making consumers more aware of the fungicides in the products that they consume including ornamentals. This scenario highlights the importance of searching for alternative products to synthetic fungicides. During this research, the use of calcium as an alternative management strategy …

Surrogate Modeling Of Nonlinear Components And Circuits, Byron William Byars

All Theses

Surrogate models are simplified approximations of functions that are described by complex equations. Surrogate modeling of physical systems have been used in various fields such as biology, fluid dynamics, climate modeling, and various other engineering disciplines. This data-driven approach is used to decrease computational cost, decrease computation time, or when the output of a system is diffcult or impossible to measure, by using a \black-box" method to approximate the output given inputs. In regards to circuit analysis, surrogate models can be used to decrease computation time and computational load.

In this thesis, surrogate modeling is used to model various nonlinear …

Supporting Us Army Next-Generation Ground Vehicle Simulation Modeling Using An Integrated Ontology Suite, Edward Louis

All Theses

The development of the US Army’s next-generation of ground vehicle systems is supported by simulations that predict vehicle performance and inform engineering design choices in the design and acquisition process. In this paper, we describe the development of an Integrated Ontology Suite to support modeling and simulation of next generation military ground vehicles. The ontology suite is intended to address model reuse challenges and increase the shared understanding of ground vehicle system simulations. It is intended to function in a Model Library structure that stores, documents, assembles, and executes vehicle simulations. The ontology suite consists of four domain ontologies: Vehicle …

Synthesis And Characterization Of Vo2 Thin Films On Piezoelectric Substrates, Samee Azad

All Theses

Polycrystalline VO₂ thin films synthesized on two piezoelectric substrates (AT-cut quartz and GaN/AlGaN/GaN/Si) using low pressure direct oxidation technique have been characterized and compared to VO₂ grown on traditional non-piezoelectric substrates sapphire and SiO₂/Si. X-ray diffraction and atomic force microscopy characterization performed on the as grown films confirmed high quality of the VO₂ films grown on both the piezoelectric and non-piezoelectric substrates. Changes in material properties associated with the semiconductor metal transition (SMT) of the VO₂ films were investigated through resistivity and transmitted optical power changes measured across the SMT. It was observed that …

Unmanned Ground Vehicle Proximal Sensing For Forage Biomass Production Estimations, Curtis Erwin

All Theses

A large increase in productivity could be realized by small increases in efficiency and utilization on grasslands due to their large area. Pre-harvest biomass estimations can help forage producers make better informed management decisions. Producers of dry hay and hay silage can better identify plant growth stages and the optimal time to harvest. Grazers can better determine the most efficient number of animals and stocking density. The goal of this study was to create a novel pre-harvest biomass estimation method utilizing compressed height combined with an unmanned ground vehicle (UGV). A compression plate named a “compression ski” was constructed and …

Optical Control System For Atmospheric Turbulence Mitigation, Martyn Lemon

All Theses

Propagation of laser light is distorted in the presence of atmospheric turbulence. This poses an issue for sensing, free-space optical communications, and transmission of power. With an ever-increasing demand for high-speed data communications, particularly between satellites, unmanned vehicles, and other systems that benefit from a point-to-point link, this issue is critical for the field. A variety of methods have been proposed to circumvent this issue. Some major categories include the manipulation of the light’s structure, an adaptive scheme at the optical receiver, scanning mirror systems, or a transmission of simultaneous signals with a goal to improve robustness.

There is an …

Multiple Objective Function Optimization And Trade Space Analysis, Yifan Xu

All Theses

Optimization can assist in obtaining the best possible solution to a design problem by varying related variables under given constraints. It can be applied in many practical applications, including engineering, during the design process. The design time can be further reduced by the application of automated optimization methods. Since the required resource and desired benefit can be translated to a function of variables, optimization can be viewed as the process of finding the variable values to reach the function maxima or minima. A Multiple Objective Optimization (MOO) problem is when there is more than one desired function that needs to …

Venomic Characterization Of A Medically Relevant Rear-Fanged Snake, Conophis Lineatus (Dipsadidae: Xenodontinae), From Middle America, Tristan Schramer

All Theses

Most traditional research on snake venoms has focused on front-fanged snake families (Viperidae, Elapidae, and Atractaspididae). However, venom is now generally accepted as being a much more broadly possessed trait within snakes, including species traditionally considered harmless. Unfortunately, due to historical inertia and methodological challenges, the toxin repertoires of non-front-fanged snake families (e.g., Colubridae, Dipsadidae, and Natricidae) have been heavily neglected despite the knowledge of numerous species capable of inflicting medically relevant envenomations. Integrating proteomic data for validation, we perform a de novo assembly and analysis of the Duvernoy’s venom gland transcriptome of the Central American Road Guarder (Dipsadidae: Xenodontinae: …

Investigating Attention Modeling Differences Between Older And Younger Drivers, Kathryn Baringer

All Theses

As in-vehicle technologies (IVTs) grow in both popularity and complexity, the question of whether these IVTs improve, or hinder, driver performance has gained more attention. The ability to predict when a driver will be looking at the road or a display on the car’s dashboard or center console is crucial to understanding the impact of the recent tech-heavy trend in car designs on safety and the extent to which IVTs compete with the primary driving task for visual resources. The SEEV model of visual attention has been shown to be able to predict the probability of attending an area if …

Effects Of Polymer Side-Group Size On Interfacial Mechanics Of Graphene-Polymer Nanocomposites, Grace Brokaw

All Theses

Graphene-reinforced polymer nanocomposites possess excellent mechanical, thermal, and electrical properties, which make them promising candidates for various applications. Favorable interfacial interactions and mechanics between graphene sheets and polymer matrices are often essential to achieve superior mechanical properties. Nevertheless, it remains largely elusive how molecular features of polymer systems, particularly the side-group size of polymer chains, affect the interfacial mechanics between graphene sheets and polymer matrices, primarily due to challenges in well controlling these features in experiments. On the other hand, exploring their roles in the mechanical properties of graphene-polymer nanocomposites is very expensive to study with all-atomistic molecular dynamics (MD) …

Understanding Movement, Habitat Use, And Habitat Selection By Largemouth Bass (Micropterus Nigricans X Salmoides) And Alabama Bass (Micropterus Henshalli) On Lake Hartwell, South Carolina, Deon Kerr

All Theses

Alabama Bass (Micropterus henshalli) were illegally introduced into the upper Savannah River Basin 15-20 years ago and have since become abundant as well as problematic ecologically. Acoustic telemetry was used to quantify diel movement, habitat use, and habitat selection of Alabama Bass and Largemouth Bass in Lake Hartwell, SC across seasons (June 2021-July 2022) with the goal of informing ongoing habitat enhancement efforts. Across all seasons, Alabama Bass conducted diel horizontal migrations from deeper offshore habitats during the day to nearshore, shallow habitats at night. Daytime Alabama Bass movement rates in offshore waters were higher than nighttime movement rates. Largemouth …

Flexural Testing Of Precast Reinforced Concrete Bridge Slabs, Evaluation Of Deterioration And Strengthening Applications, Alyssa Leaman

All Theses

This thesis investigates the strength of flat precast concrete slabs that were taken from decommissioned South Carolina bridges. The specimens tested spanned 14 ft (4.3 m) or 15 ft (4.6 m), were 5 ft (1.5 m) or 5.5 ft (1.7 m) wide, and 8.25 in (210 mm) thick. In South Carolina, there are approximately 3000 similar bridges that use these slab members. Testing was conducted to determine the flexural capacity of “typical” slabs and the residual strength of slabs having visible deterioration of both the rebar and the concrete. For the slabs that were load rated below the new standards, …

Utilizing Systematic Design And Shape Memory Alloys To Enhance Actuation Of Modular High-Frequency Origami Robots, Jessica M. Den Haese

All Theses

Shape memory alloys (SMAs) describe a group of smart metallic materials that can be deformed by external magnetic, thermal, or mechanical influence and then returned to a predetermined shape through the cycling of temperature or stress. They have several advantages, such as having excellent mechanical properties, being low cost, and being easily manufactured, while also providing a compact size, completely silent operation, high work density, and requiring less maintenance over time. SMAs can undergo sold-to-solid phase transformations, and it is because of these phase transformations that they can experience shape memory effect (SME); or the ability to recover from a …

Koopman Operator Theory And The Applied Perspective Of Modern Data-Driven Systems, Alex Krolicki

All Theses

Recent theoretical developments in dynamical systems and machine learning have allowed researchers to re-evaluate how dynamical systems are modeled and controlled. In this thesis, Koopman operator theory is used to model dynamical systems and obtain optimal control solutions for nonlinear systems using sampled system data. The Koopman operator is obtained using data generated from a real physical system or from an analytical model which describes the physical system under nominal conditions. One of the critical advantages of the Koopman operator is that the response of the nonlinear system can be obtained from an equivalent infinite dimensional linear system. This is …

Performance Based Design And Machine Learning In Structural Fire Engineering: A Case For Masonry, Deanna Craig

All Theses

The volatile and extreme nature of fire makes structural fire engineering unique in that the load actions dictating design are intense but not geographically or seasonally bound. Simply, fire can break out anywhere, at any time, and for any number of reasons. Despite the apparent need, fire design of structures still relies on expensive fire tests, complex finite element simulations, and outdated procedures with little room for innovation. This thesis will make a case for adopting the principles of performance-based design and machine learning in structural fire engineering to simplify the process and promote the consideration of fire in all …

If You Give A Beetle A Maple: Anoplophora Glabripennis Habitat Selection Patterns On An Island In South Carolina, Meredith Bean

All Theses

At the epicenter of the Asian longhorned beetle (Anoplophora glabripennis Motschulsky) quarantine zone in South Carolina, a small island containing an actively growing subpopulation of A. glabripennis had not completely killed its 37 host trees in 2020. Before these trees were removed and destroyed according to the USDA Eradication Program protocols, I performed an observational study to examine the microhabitat selection tendencies of the invasive A. glabripennis within this satellite infestation. After cataloging >14,000 oviposition sites and >1,600 exit holes created by A. glabripennis, I found dispersal trends according to a host’s stem status (single or multi-stemmed), vertical …

Barriers And Facilitators In Implementing Multiplatform Remote Patient Monitoring Of Heart Failure Patients In Clinical Settings, Zachary Andrew Reilly

All Theses

Remote patient monitoring (RPM), which provides continuous monitoring of vital signs, has become increasingly utilized in patients with heart failure (HF). As this condition impacts more than 26 million Americans each year, it is important to determine the barriers and facilitators of RPM to both improve patient care and help medical professionals make more informed medical decisions. To determine these barriers and facilitators, our research team partnered with Prisma Health-Upstate to interview healthcare professionals working at Carolina Cardiology Consultants--Greenville, which uses multiple RPM systems to monitor heart failure patients.

The twelve interviews conducted support that healthcare professionals would benefit from …

Learning To Reason About Code With Assertions: An Exploration With Two Student Populations, Sarah Blankenship

All Theses

Code tracing is fundamental to students’ understanding of a program, and symbolic reasoning that entails learning to use assertions with abstract input and output values, as opposed to concrete values, enhances that understanding. Symbolic reasoning teaches students valuable abstraction and logic skills that will serve them well in all aspects of programming and their software
development careers.
We use lessons integrated into an online educational tool to supplement classroom instruction to help students learn symbolic reasoning. We explore two ways for students to learn about assertions: Writing assertions to capture the behavior of given code and solving Parsons-style problems in …

Triumph In The Suburbs: Richard Ford And The Spaces Of New Capitalism, John Gorton

All Theses

In his 1986 book America, Baudrillard noted that “the most banal suburb…is more at the centre of the world than any of the cultural manifestations of old Europe.” My thesis argues that this monumental shift from the suburbs as enclaves at the outer edges of cultural urban centers to “the centre of the world” is at the heart of Richard Ford’s realist project in his Pulitzer Prize winning Bascombe series starting with The Sportswriter in 1986. Emergent twentieth- and twenty-first-century literature scholars have been interested in the schism between the fictionalized representation and the lived experience of suburbia — while …

Transforming Character Faces Based On Perceived Personality Traits, Kara Porter

All Theses

The ability to read other human's faces is a crucial part of everyday life. Subconsciously, the human brain analyzes someone's face within the first few seconds of seeing it, making a variety of conclusions ~\cite{FacePerp} such as gathering information about emotional state and assuming character traits this person might possess. The purpose of this thesis is to create a tool that allows a user to alter features of a character's three dimensional (3D) face mesh to look increasingly or decreasingly like the character possesses certain personality traits. Using a sample set of randomly generated faces, a survey is conducted to …