Engineering Commons^™

The Importance Of Hand Motions For Communication And Interaction In Virtual Reality, Alex Adkins

All Dissertations

Virtual reality (VR) is a growing method of communication and play. Recent advances have enabled hand-tracking technologies for consumer VR headsets, allowing virtual hands to mimic a user's real hand movements in real-time. A growing number of users now utilize hand-tracking when using VR to manipulate objects or to create gestures when interacting with others. As VR grows as a tool and communication platform, it is important to understand how the rising prevalence of hand-tracking technology might affect users' experiences.

The goal of this dissertation is to investigate, through a series of experiments, how using hand motions in VR influences …

High-Performance Vlsi Architectures For Lattice-Based Cryptography, Weihang Tan

All Dissertations

Lattice-based cryptography is a cryptographic primitive built upon the hard problems on point lattices. Cryptosystems relying on lattice-based cryptography have attracted huge attention in the last decade since they have post-quantum-resistant security and the remarkable construction of the algorithm. In particular, homomorphic encryption (HE) and post-quantum cryptography (PQC) are the two main applications of lattice-based cryptography. Meanwhile, the efficient hardware implementations for these advanced cryptography schemes are demanding to achieve a high-performance implementation.

This dissertation aims to investigate the novel and high-performance very large-scale integration (VLSI) architectures for lattice-based cryptography, including the HE and PQC schemes. This dissertation first presents …

Measurement And Evaluation Of Roadway Geometry For Safety Analyses And Pavement Material Volume Estimation For Resurfacing And Rehabilitation Using Mobile Lidar And Imagery-Based Point Clouds, Leonildo Nelson Cassule

All Dissertations

Roadway safety is a multifaceted issue affected by several variables including geometric design features of the roadway, weather conditions, sight distance issues, user behavior, and pavement surface condition. In recent years, transportation agencies have demonstrated a growing interest in utilizing Light Detecting and Ranging (LiDAR) and other remote sensing technologies to enhance data collection productivity, safety, and facilitate the development of strategies to maintain and improve existing roadway infrastructure. Studies have shown that three-dimensional (3D) point clouds acquired using mobile LiDAR systems are highly accurate, dense, and have numerous applications in transportation. Point cloud data applications include extraction of roadway …

Large Genomes Assembly Using Mapreduce Framework, Yuehua Zhang

All Dissertations

Knowing the genome sequence of an organism is the essential step toward understanding its genomic and genetic characteristics. Currently, whole genome shotgun (WGS) sequencing is the most widely used genome sequencing technique to determine the entire DNA sequence of an organism. Recent advances in next-generation sequencing (NGS) techniques have enabled biologists to generate large DNA sequences in a high-throughput and low-cost way. However, the assembly of NGS reads faces significant challenges due to short reads and an enormously high volume of data. Despite recent progress in genome assembly, current NGS assemblers cannot generate high-quality results or efficiently handle large genomes …

Highly Adherent Antimicrobial Coatings For Orthopedic Implants, Mikhail Bredikhin

All Dissertations

Fracture-related infections (FRIs) are the most devasting sort of complications associated with fracture fixation devices, as they lead to patients’ morbidity, prolonged hospitalization, amputations, and even death.External fixators additionally suffer from pin site infections (PSIs), which initiate at the skin entry points of the skin-metallic pin interface present in the external fixation of the damaged bones, often causing deep tissue infection and osteomyelitis. Small percutaneous pins, commonly known as Kirschner wires (K-wires), are used to treat complex fractures and deformities.They are drilled inside the diseased bone for the healing period and are left protruding outside the skin for fixation adjustments …

Likeliness To Recommend: A Mixed Methods Analysis Of Consumer Perception Of Homebuilders, Todd Usher

All Dissertations

Measures of consumers’ likeliness to recommend a business or company have been shown to relate to business performance. Less is known about how such scores might operate in the homebuilding industry. This study examines the factors influencing consumers’ perceptions of homebuilders, an area with little published research. Using a sequential mixed-methods approach, the study analyzes survey data from consumers (N = 366) who had new homes built within the preceding 12 months. Quantitative analyses of the data reveal several aspects of consumers’ likeliness to recommend a homebuilder. One finding of great interest is that consumers of the survey were more …

Investigating Spatial Heterogeneity In Myocardial Wound Environments To Improve Therapy, Michael Potter

All Dissertations

Heart failure is a broad pathology manifestation categorized by an inability of the heart to successfully pump blood throughout the vast vessel network of the body. Within the United States, heart failure is projected to increase by approximately 46% from 2012 to 2030. Modalities of heart failure are generally related to wall mechanics that are impacted following myocardial infarction events. Interplay exists between the wall mechanics, responding cell populations, and the spatial heterogeneities in the resultant scar. This interplay directs the myocardium towards heart failure modalities governed by overly stiff or compliant states. It is essential to elucidate details underlying …

Essays On Perioperative Services Problems In Healthcare, Amogh S. Bhosekar

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One of the critical challenges in healthcare operations management is to efficiently utilize the expensive resources needed while maintaining the quality of care provided. Simulation and optimization methods can be effectively used to provide better healthcare services. This can be achieved by developing models to minimize patient waiting times, minimize healthcare supply chain and logistics costs, and maximize access. In this proposal, we study some of the important problems in healthcare operations management. More specifically, we focus on perioperative services and study scheduling of operating rooms (ORs) and management of necessary resources such as staff, equipment, and surgical instruments. We …

On Variants Of Sliding And Frank-Wolfe Type Methods And Their Applications In Video Co-Localization, Seyed Hamid Nazari

All Dissertations

In this dissertation, our main focus is to design and analyze first-order methods for computing approximate solutions to convex, smooth optimization problems over certain feasible sets. Specifically, our goal in this dissertation is to explore some variants of sliding and Frank-Wolfe (FW) type algorithms, analyze their convergence complexity, and examine their performance in numerical experiments. We achieve three accomplishments in our research results throughout this dissertation. First, we incorporate a linesearch technique to a well-known projection-free sliding algorithm, namely the conditional gradient sliding (CGS) method. Our proposed algorithm, called the conditional gradient sliding with linesearch (CGSls), does not require the …

Enhancing The Performance Of Poly(3-Hexylthiophene) Based Organic Thin-Film Transistors Using An Interface Engineering Method, Eyob Negussie Tarekegn

All Dissertations

An original design and photolithographic fabrication process for poly(3-hexylthiophene-2, 5-diyl) (P3HT) based organic thin-film transistors (OTFTs) is presented. The structure of the transistors was based on the bottom gate bottom contact OTFT. The fabrication process was efficient, cost-effective, and relatively straightforward to implement. Current–voltage (I-V) measurements were performed to characterize the primary electronic properties of the transistors. The measured mobility of these transistors was significantly higher than most results reported in the literature for other similar bottom gate bottom contact P3HT OTFTs. The higher mobility is explained primarily by the effectiveness of the fabrication process in keeping the interfacial layers …

Permanently-Installed Distributed Pressure Sensors For Downhole Applications, Xuran Zhu

All Dissertations

Technology advancements (e.g., hydraulic fracturing and horizontal drilling) to recover unconventional oil and gas (UOG) resources are critical in maintaining future U.S. oil and gas production levels. Permanently installed distributed downhole pressure sensors could monitor fracture propagation, assess the effectiveness of hydraulic fracturing, and optimize hydraulic fracturing placement so that overall UOG recovery efficiency can be increased. However, the harsh environment (high temperatures, high pressures, strong vibration, and presence of brine, mud, debris, hydrate, and various gases), the long data telemetry distance, and the requirements of reliability and service lifetime make the downhole monitoring a very challenging task. To combat …

Metabolic Engineering Of Yarrowia Lipolytica For Enhanced Peroxisomal Production Of Polyhydroxyalkanoates, Michael Spagnuolo

All Dissertations

Traditional chemical processes are made inefficient by the generation of side products and reactions that fail to reach completion. Bioprocesses, on the other hand, lose product potential due to the necessity of growing the organism required to produce the desired compounds. The field of metabolic engineering often seeks to alter this balance between product formation and cell growth to generate more product from the same quantity of feed (reagent). In addition to balance, such organisms may also be engineered to produce the desired products from nontraditional substrates, such as waste compounds. In resource-poor environments, the ability to produce a wanted …

Ligand-Promoted Dissolution Of Uranyl Phosphate Across Scales, Brennan Ferguson

All Dissertations

The formation of uranyl phosphate precipitate is a remediation strategy because the low solubility of uranyl phosphate minerals, like chernikovite, limits the mobility of uranium in contaminated soils. However, organic ligands can complex with aqueous metal cations to form more soluble species. For example, citrate is a commonly occurring organic ligand produced by plants and microbes that increases the solubility of uranium and therefore the dissolution of uranyl phosphate minerals in the uranyl phosphate-citrate system. This effect is an important control on the mobility of uranium in organic-rich, and near-surface vegetated environments. Nevertheless, key aspects of the citrate-uranyl phosphate system …

Mechanics Modeling Of Non-Rigid Origami: From Qualitative To Quantitative Accuracy, Jiayue Tao

All Dissertations

Origami, the ancient art of paper folding, has recently evolved into a design and fabrication framework for various engineering systems at vastly different scales: from large-scale deployable airframes to mesoscale biomedical devices to small-scale DNA machines. The increasingly diverse applications of origami require a better understanding of the fundamental mechanics and dynamics induced by folding. Therefore, formulating a high-fidelity simulation model for origami is crucial, especially when large amplitude deformation/rotation exists during folding.

The currently available origami simulation models can be categorized into three branches: rigid-facet models, bar-hinge models, and finite element models. The first branch of models assumes that …

Multi-Criteria Performance Evaluation And Control In Power And Energy Systems, Payam Ramezani Badr

All Dissertations

The role of intuition and human preferences are often overlooked in autonomous control of power and energy systems. However, the growing operational diversity of many systems such as microgrids, electric/hybrid-electric vehicles and maritime vessels has created a need for more flexible control and optimization methods. In order to develop such flexible control methods, the role of human decision makers and their desired performance metrics must be studied in power and energy systems. This dissertation investigates the concept of multi-criteria decision making as a gateway to integrate human decision makers and their opinions into complex mathematical control laws. There are two …

Implementation Of Sic Power Electronics For Green Energy Based Electrification Of Transportation, Naireeta Deb

All Dissertations

Increase in greenhouse gas emission poses a threat to the quality of air thus threatening the future of living beings on earth. A large part of the emission is produced by transport vehicles. Electric vehicles (EVs) are a great solution to this threat. They will completely replace the high usage of hydrocarbons in the transport sector. Energy efficiency and reduced local pollution can also be expected with full implementation of electrification of transportation. However, the current grid is not prepared to take the power load of EV charging if it were to happen readily. Moreover, critics are doubtful about the …

Multiple Heat Exchanger Cooling System For Automotive Applications – Design, Mathematical Modeling, And Experimental Observations, Zaker Syed

All Dissertations

The design of the automotive cooling systems has slowly evolved from engine-driven mechanical to computer-controlled electro-mechanical components. With the addition of computer-controlled variable speed actuators, cooling system architectures have been updated to maximize performance and efficiency. By switching from one large radiator to multiple smaller radiators with individual flow control valves, the heat rejection requirements may be precisely adjusted. The combination of computer regulated thermal management system should reduce power consumption while satisfying temperature control objectives. This research focuses on developing and analyzing a multi-radiator system architecture for implementation in ground transportation applications. The premise is to use a single …

Infusing Kirigami Principles Into Design Of Mechanical Properties, Hesameddin Khosravi

All Dissertations

The emergence of mechanical metamaterials — which derive their properties primarily from the underlying architecture rather than the constituent material — has unleashed a new era of material design and functionalities. To fully materialize the promising potentials of metamaterials, it is crucial to develop versatile, scalable, and easy-to-fabricate methods that can both generate and tailor the underlying periodic architecture. To this end, we propose the use of kirigami — a popular recreational art of cutting and manipulating paper — as a platform to create periodicity and super-stretchability. Kirigami has become a design and fabrication framework for constructing metamaterials, robotic tools, …

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 …

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 …

Active Rheological And Stiffening Control Of Cementitious Systems For Additive Manufacturing, Abdul Basit Peerzada

All Dissertations

Technological advancements and automation in the last two decades have made additive manufacturing of cementitious systems a reality. Among all the additive manufacturing techniques used for cementitious materials, layer-by-layer extrusion-based printing is the most used technique. For a layer-by-layer printing process, the requirements of cementitious materials vary from those of a conventional construction process. Typically, the cementitious materials are pumped to a print head using a positive-displacement pump. The pumpability of the cementitious material for a specific pumping system depends on its rheological properties. For effective pumping, the yield stress and plastic viscosity of a cementitious system should be low. …

A Benchtop Robotic Automation Approach For Manufacturing Prefilled Syringes, Yehua Zhong

All Theses

Automation and robotics have become a staple in the biological manufacturing sector due to their ability to efficiently work without operator inputs, with a high degree of accuracy and repeatability. Industrial robotic arms, in particular, present themselves as valuable tools for biological manufacturing scenarios that require customized solutions due to their ease of programming and flexibility. The traditional hospital-focused healthcare system was organically developed to address acute conditions, however, in recent years, due to the unprecedented occurrence of emergencies happening more frequently, fast and efficient drug production becomes important [17]. This thesis represents the use of a benchtop robot and …

Geology-Based Shear-Wave Velocity Model Of Reference Site Conditions In South Carolina For Seismic Site Response Analysis, Camilius Amevorku

All Dissertations

Assessing earthquake hazard in the State of South Carolina is important because it is one of the most seismically active regions of the eastern United States and has experienced earthquakes of damaging levels in the historical past. Examples of these damaging seismic events are the 1886 Charleston earthquake (M 6.7 to 7.5) and the 1913 Union County earthquake (M 4.5 to 5.5).

Small-strain shear-wave velocity (V_S) is an important parameter in performing site response analysis. The deep nature of the top of reference firm rock (i.e., V_S ≥ 760 m/s or B-C boundary) due to …

Design Of Arbitrary Planar Optical Devices With Full Phase Control Using Nanoimprinting Of Refractive Index, Matthew Panipinto

All Theses

Planar optical devices offer a lightweight solution to the constraints found in traditional optical devices. While subwavelength patterning of optics offers attractive performance and size, traditional fabrication methods demand a trade-off between resolution and throughput that presents a significant hurdle for the widespread use of subwavelength devices. Nanoimprinting of refractive index (NIRI) is a novel fabrication method pioneered in previous work that offers promise in mitigating the throughput issues that hamstring traditional fabrication methods. However, NIRI has not been shown to impart full $2\pi$ phase control in planar optical devices, nor has a method for fabricating arbitrary designs using the …

Multi-Robot Symbolic Task And Motion Planning Leveraging Human Trust Models: Theory And Applications, Huanfei Zheng

All Dissertations

Multi-robot systems (MRS) can accomplish more complex tasks with two or more robots and have produced a broad set of applications. The presence of a human operator in an MRS can guarantee the safety of the task performing, but the human operators can be subject to heavier stress and cognitive workload in collaboration with the MRS than the single robot. It is significant for the MRS to have the provable correct task and motion planning solution for a complex task. That can reduce the human workload during supervising the task and improve the reliability of human-MRS collaboration. This dissertation relies …

A Protocol For Coupling Volumetrically Dynamic In Vitro Experiments To Numerical Physiology Simulation For A Hybrid Cardiovascular Model, Abraham Umo, Ethan Kung

Publications

Objective: The Physiology Simulation Coupled Experiment (PSCOPE) is a hybrid modeling framework that enables a physical fluid experiment to operate in the context of a closed-loop computational simulation of cardiovascular physiology. Previous PSCOPE methods coupled rigid experiments to a lumped parameter network (LPN) of physiology but are incompatible with volumetrically dynamic experiments where fluid volume varies periodically. We address this limitation by introducing a method capable of coupling rigid, multi-branch, and volumetrically dynamic in-vitro experiments to an LPN. Methods: Our proposed method utilizes an iterative weighted-averaging algorithm to identify the unique solution waveforms for a given PSCOPE model. We confirm …

Design And Development Of A Multi-Material, Cost-Competitive, Lightweight Mid-Size Sports Utility Vehicle’S Body-In-White, Amit M. Deshpande, Rushabh Rajesh Sadiwala, Nathan Brown, Sai Aditya Pradeep, Leon M. Headings, Ningxiner Zhao, Brad Losey, Ryan Hahnlen, Marcelo J. Dapino, Gang Li, Srikanth Pilla

Publications

Vehicle light-weighting has allowed automotive original equipment manufacturers (OEMs) to improve fuel efficiency, incorporate value-adding features without a weight penalty, and extract better performance. The typical body-in-white (BiW) accounts for up to 40% of the total vehicle mass, making it the focus of light-weighting efforts through a) conceptual redesign b) design optimization using state-of-the-art computer-aided engineering (CAE) tools, and c) use of advanced high strength steels (AHSS), aluminum, magnesium, and/or fiber-reinforced plastic (FRP) composites. However, most of these light-weighting efforts have been focused on luxury/sports vehicles, with a relatively high price range and an average production of 100,000 units/year or …

The Professional Constructor, Full Issue, Volume 47, Number 02

The Professional Constructor

No abstract provided.

Tunable Filtration Of Particles During Dip-Coating, Connor Copeland

All Theses

When a solid substrate is withdrawn from a liquid bath a thin coating is deposited whose thickness is given by the Landau-Levich-Derjaguin (LLD) law. We perform an experimental study of dip coating of particle suspensions showing that particles of a given size can become entrained in the meniscus by the competition between viscous and surface tension forces. This is called capillary filtration and can be used as a tunable dynamic filter. For single particle suspensions, filtration can be in terms of either clumps or single particles, with the relevant entrainment points depending upon the rheology of the working fluid, either …