Engineering Commons^™

Photo-Carbon Monoxide Releasing Molecules For Antibacterial Benefits In Vascular Grafts, Beste Caner

Theses and Dissertations

Globally, the annual hemodialysis procedures surpass 1.5 million, emphasizing the vital role of reliable vascular access methods. However, common challenges like access infections and clot-induced blood flow reduction necessitate innovative solutions. This study delved into the potential therapeutic role of carbon monoxide (CO) and its effects on both endothelialization and non-pathogenic bacteria causing infections. The primary focus was evaluating the impact of loading different concentrations of carbon monoxide-releasing molecules (CORMs), specifically CORM diketone 4 (DK4), within 2D spin-coated films on cultured E. coli and endothelial cells. Initial assessments of CO release kinetics from DK4-loaded films demonstrated that the 10% condition …

The Importance Of Data Preparation In A Data Science Problem, Sophia Beard

Data Science Undergraduate Honors Theses

This study is going to be based on an inventory outlier automation data science problem that is being solved to identify and prescribe inventory level outliers to help keep shelves stocked in terms of beverages. The objective of this paper will address why it is so important to understand the data that is involved in a particular data science problem and how planning ahead ensures a successful outcome in the data science world. In this data science project, Spatiotemporal Outlier Analysis for Inventory Intervention Automation, it was crucial for the team to understand, research, and visualize the data we were …

Engineering Sustainable Bridge Deck Rehabilitation: Evaluating Mechanical And Electro-Chemical Properties Of Rapid-Set Patching Materials And Their Influence On Repair Durability, James Roberts

All Theses

As the state of the US infrastructure continues to deteriorate over time, a prominent issue especially in the field of reinforced concrete structures has been the ability to properly rehabilitate and extend the design service life of these structures. A majority of our existing reinforced concrete bridges were built in the construction boom during the 60’s, 70’s and 80’s, and were originally designed with a service life of approximately 50 years, thus showing that many structures are close to or have already exceeded their intended service life. Additionally, with a poor history of government infrastructure funding, it is seen to …

Application Of An Information Gain Model In A Motor Learning Task: An Application In A Laparoscopic Surgical Skills Task, Matthew Ball

All Theses

Psychomotor skills are comprised of physical movements and mental adaptations of movements to complete a task, generally using complex tools or components. Laparoscopic surgery training tasks are a prime example of tasks requiring psychomotor skills due to their demand for both fine hand movements and constant mental adaptation to the changing environment of the human body. A typical evaluation of these skills can be accomplished using learning curves, a graphical representation of skill growth in which a performance metric is plotted over a time experience metric. Previously, in the literature, several learning curves have been generated from the performance within …

Efficacy Of Virtual Reality-Based Simulations In Training Aviation Maintenance Technicians On Maintenance Procedures, Gayatri Anoop

All Theses

The COVID-19 pandemic forced institutions of higher education (IHEs) to halt in-person classes and transition to online platforms. Given the intricate process of adapting hands-on experiments to the online environment, this transition seemed particularly challenging for Science, Technology, Engineering, Mathematics, and Medicine (STEMM) labs. The abrupt nature of this transition added to the difficulties, given that the IHEs were inadequately prepared for seamless continuity during the pandemic. In the first phase of this project, a literature review was conducted to understand the impact of COVID-19 pandemic on education. Specifically, the review explored the challenges that institutions of higher education faced, …

Investigation Of Domain Formation During Phase Separation In A Mixture Of Flexible And Rigid Biopolymers, Steven Huntley

All Theses

Complex fluids and heterogenous mixtures composed of multiple types of polymers are found throughout industrial and biological fluid systems. For example, extrusion based additive manufacturing systems pass dense mixtures of polymers through the extrusion heads to deposit composite polymeric materials. In cells, active and complex mixtures of biopolymers self-organize into assemblies that perform critical physiological functions.

Polymers in dense solutions undergo phase separation as a result of differences in physiochemical properties. A few examples of these properties include charge, structure, rigidity, and hydrophobicity. We observe the formation of polymer domains composed of rigid and a flexible biopolymer species that phase …

Elucidating The Impact Of Casting Solvent On Vanadium Ion Transport In Solution-Cast Ionomer Biocomposites Containing Lignin, Zhongyu Wang

All Theses

This paper attempts to investigate the influence of solvent choice to the Nafion-lignin proton exchange membranes that used in the vanadium redox flow batteries. The influence of two different solvents: DMF and DMSO were investigated in this paper. Results show that when using DMSO as solvent, Nafion-lignin membranes' vanadium ion cross over can be greatly reduced in comparing with membranes prepared from DMF. Also, membranes prepared from DMSO also show higher water uptake ability and lower ion exchange capacity than the membranes prepared from DMF. This paper has also investigated the influence of lignin type to the membranes. Results show …

Analyzing An In-Line Compression Management System For Improved Performance In A High-Performance Computing Environment, Steven Platt

All Theses

High-performance computing (HPC) has enabled advancements in computation speed and resource cost by utilizing all available server resources and using parallelization for speedup. This computation scheme encourages simulation model development, massive data collection, and AI computation models, all of which store and compute on massive amounts of data. Data compression has enhanced the performance of storing and transferring this HPC application data to enable acceleration, but the benefits of data compression can also be transferred to the active allocated memory used by the application. In-line compression is a compression method that keeps the application memory compressed in allocated memory, decompressing …

Digital Twin In Military Ground Vehicles: Design And Predictive Maintenance, Conner W. Eddy

All Theses

Digital twin technology builds upon virtual engineering models, computer simulation, and real-time field data streaming to enable next-generation designs and predictive maintenance. A digital twin is a computer-based high-fidelity collection of models that predicts the performance of dynamic systems per operating cycles, input feature parameters, and data communication from a physical plant. Product Lifecycle Management (PLM) is growing in importance and is central to virtual design processes where the digital twin toolset fits into this emerging architecture. The product design process can be advanced using digital twin resources by eliminating the need for, and cost from, continual physical prototyping, reliability …

Evaluation And Development Of Tourniquet Test Methods, Catherine Pitts

All Theses

Since the beginning of the 21^st century the general perspective on tourniquets has changed to a more positive outlook on their life saving abilities. The US has seen a greater number of mass casualty events, and conflicts across the globe have led to an increased use of tourniquets. The increased demand has also led to faulty counterfeit tourniquets and improvised tourniquets that don not properly occlude blood flow or cause significant nerve damage to the injured limb.

ASTM started designing a tourniquet testing standard with experts in the tourniquet community to cut down on the dangers of tourniquet use. …

Modeling Of Multi-Period Disaster Logistics Planning In The State Of South Carolina, Emma Simon

All Theses

South Carolina is one of the most vulnerable states in the United States to the impact of hurricanes. Currently, when threatened with a natural disaster such as a hurricane, the state government makes many vital decisions based on knowledge and experience. In this study, the distribution of disaster relief commodities to meet immediate needs is analyzed through two models for the case of South Carolina to generate an optimal logistics strategy that considers the social vulnerability of affected populations. The first model is a multi-objective pre-disaster logistics model that uses a four-index formulation for the multiple trip vehicle routing problem. …

Sulfonated Lignin-Based Ionomer Biocomposite Membranes For Redox Flow Batteries, Aiswarya Mechoor

All Theses

The current benchmark membrane for vanadium redox flow batteries (VRFBs), Nafion™, accounts for up to 40% of the cost of the battery and suffers from poor ion selectivity, leading to diminished battery performance. Consequently, alternative ionomer membranes, such as sulfonated poly(ether ether ketone) (SPEEK), have recently garnered attention due to their lower cost and similar performance properties to Nafion. However, like Nafion, SPEEK also suffers from poor ion selectivity. In this study, we attempt to address the issue of poor ion selectivity by developing SPEEK–lignin composite membranes containing fractionated and functionalized lignin. Specifically, two lignin fractions – a low molecular …

Improved Ballistic Impact Resistance Of Nanofibrillar Cellulose Films With Discontinuous Fibrous Bouligand Architecture, Colby Caviness

All Theses

Natural protective materials offer unparalleled solutions for impact-resistant material designs that are simultaneously lightweight, strong, and tough. Particularly, the dactyl club of mantis shrimp features chitin nanofibrils organized in a Bouligand structure, which has been shown to effectively dissipate high-impact energy during powerful strikes. The mollusk shells also achieve excellent mechanical strength, toughness, and impact resistance with a staggered, layer-by-layer structure. Previous studies have shown that hybrid designs, by combining different bioinspired microstructures, can lead to enhanced mechanical strength and energy dissipation capabilities. Nevertheless, it remains unknown whether combining Bouligand and staggered structures in nanofibrillar cellulose (NFC) films, forming a …

Evaluating Company Culture Of Roofing Contracting Companies To Attract And Retain Women In The Industry, Gopika Viswanathan

All Theses

The US construction industry, similar to many other industries, has a low representation of women. This difference is even more pronounced in construction trades, such as the roofing industry. The admission of more women into the industry is important to address workforce shortage issues that the industry is facing. Company culture has been cited as one of the primary reasons why women choose not to enter the industry or face barriers during their careers. The main objective of this study was to evaluate the company culture of roofing companies through factors identified by literature and by women and companies in …

Depression And Anxiety: Investigating The Impacts Of Scheduling On The Mental Health Of Healthcare Workers During The Covid-19 Pandemic, Christofer Gonzaga

All Theses

Depression is a growing problem in the United States and has ballooned into a globally recognized mental health issue that affects shift workers in various fields (Lee et al., 2017). Rates of depression and anxiety have been shown to be substantially increasing and the COVID-19 pandemic amplified this prevalence of depression and anxiety. In the United States, the prevalence of depression symptoms was more than 3- fold higher during COVID-19 compared to before the pandemic (Ettman et al., 2020). The delivery of healthcare services is an ongoing and dynamic process, requiring clinicians to work in various shifts to ensure the …

The Effect Of Central Screw And Post Vault Containment On Reverse Total Shoulder Arthroplasty (Rsta) Baseplate Stability, Mickaela J. Gunnison

All Theses

Reverse total shoulder arthroplasty (RTSA) is a procedure that aims to fix irreversible rotator cuff damage and degenerative glenohumeral joint diseases that hinder arm abduction. One major complication of RTSA is glenoid baseplate failure resulting from increased movement at the bone-baseplate interface. This study examined 36, 12 PCF composite Sawbones® scapulae. The specimens were split equally into 6 study groups, each having different implant configurations with varying baseplate lateralization and central screws or posts. Each specimen was subjected to cyclic shear loading and failure testing on an Instron to determine implant micromotion and load values.

After testing, ANOVA tests were …

Phasor-Domain Short-Circuit Analysis Of Power Transmission Systems In The Presence Of Inverter-Based Resources, Dol Kunwar

All Theses

Although a power system is nonlinear during healthy operation because of constant power loads and controlled power injections from the sources, a conventional power system fed by synchronous generators is linear during fault, and can be represented by bus impedance matrix (Z-bus), which is useful in power system analyses such as short circuit (SC) analysis. However, With increasing penetration of inverter-based resources (IBRs) in the system, the assumption of linearity of the faulted network does not hold. This impacts the analyses relying on Z-bus and Thevenin’s equivalent impedance (TEI), such as certain protection schemes set using short circuit analysis. Therefore, …

Light-Induced Phase Separation Purification For Monoclonal Antibodies, Xuyang Chen

All Theses

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Multi-Domain Secure Dds Networks For Aerial And Ground Vehicle Communications, Daniel Pendleton

All Theses

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Towing Tank Trials Of Hydrokinetic Turbine Scale Model To Support Marine Energy System Verification, Shahab Rouhi

LSU New Orleans Theses and Dissertations

In response to the escalating demand for sustainable energy solutions and the critical reevaluation of conventional fossil fuels due to environmental concerns, this dissertation embarks on a comprehensive exploration of hydrokinetic energy as a promising alternative. The study delves into the underexplored domain of hydrokinetic energy, leveraging innovative methodologies for effective utilization and harnessing, particularly through the development and investigation of hydrokinetic turbines.

In the realm of hydrokinetic energy conversion, our research has exclusively concentrated on horizontal-axis turbines, distinct from other turbine configurations. Noteworthy is the adaptation of a conventional horizontal-axis wind turbine for water currents, revealing enhanced performance through …

Hierarchical Power Converter Physical Design, Tristan Mark Evans

Graduate Theses and Dissertations

The field of power electronics is undergoing rapid advancement that is driven by the need for further electrification in all aspects of power generation and transmission, transportation, and consumer goods. Recent advances in wide bandgap (WBG) semiconductor technologies continue to push their adoption in systems with higher power densities and conversion efficiencies. However, the way in which the components of these systems are designed has not kept pace with the rapidly evolving landscape of their applications and often requires costly, manual design iteration. Therefore, new methods are needed to improve this design process. Packaging of power devices is a critical …

Summonable Construction Delivery Robot, Kevin M. Lewis

Honors Capstones

In many different construction industries, there is a need for tools, parts, and other necessary items to be transported quickly and efficiently over various types of terrain. Human resources have often been used to address these needs, which can become very time and cost inefficient over long periods. The design proposal here is aimed at addressing this need by developing an autonomous outdoor mobile robot based on a quadrupedal robot design. This approach differs by incorporating a wheeled and quadrupedal hybrid actuation system that provides terrain negotiation and speed at the appropriate times. The team uses Robot Operating System (ROS) …

Great South Metals: Slitter Head Building Process, Nabhan Karim, Evan Swierski, Raven Morin, Patrick Kelsey, Michael Williams

Senior Design Project For Engineers

Great South Metals (GSM) operates two steel slitter machines, which take large coils of flat rolled steel and cut them into smaller strips for use in customers’ applications. Setting up the working components of each machine, called the slitter head, is a precise and arduous task. This system relies on several manually performed calculations and acute attention to detail; and thus, is prone to human error. The management at GSM commissioned our team to simplify the slitter head assembly process by creating an automated computer program and make additional recommendations to improve their operations.

The program we created is a …

Multilayer Shielding Design And Analysis Of Optimal Thickness For The Storage Of Highly Radioactive Sources Concerning Environmental Safety, Md. Mahfuzul Haque Rafi, Asma Ul Husna, Abdus Sattar Mollah

International Journal of Nuclear Security

As a kind of radiological protection, multilayer shielding is superior to a single-layer shield in terms of blocking off radiation. This study examined a multilayer shielding strategy to protect employees from potentially harmful gamma radiation from highly radioactive sources such as ⁶⁰Co. This paper presents a novel strategy for cost-effective and environmentally safe radiation protection by aligning expensive and heavy materials such as W and Pb to improve their effectiveness and limit exposure below the occupational dose. The largely unpublished set of final exposure rates for the W–Pb–Fe combination was calculated by the numerical interpolation method in MATLAB software. …

Safety And Security Analysis Of Vver-1200 Reactor Pressure Vessel Under Pressurized Thermal Shock, Mohammed Sarim Salman Karim, Dr. Debashis Datta, Altab Hossain

International Journal of Nuclear Security

The reactor pressure vessel (RPV) is an important component of a nuclear power plant and of great concern to safety and security globally. Thus, the thermal system of an RPV should be ensured properly through an evaluation system that closely monitors and considers its integrity. This article describes the thermomechanical analyses for a pressurized thermal shock (PTS) scenario of a VVER-1200 RPV owing to a loss of coolant accident (LOCA) and activation of the emergency core cooling system (ECCS). The LOCA transient and activation of ECCS are modeled using ANSYS simulation software. From the analyses of the emergency core cooling …

Design And Development Of A Radiation Survey And Rescue Robot With Shielding Of Electronic Equipment From Radiation Damage With Image Radiation Mapping Facility, Md. Sifatul Muktadir, Md. Nazmul Hassan, Md. Saimon Siddique, Dewan Nazmun Nur, Altab Hossain, Ahnaf Tahmid Chowdhury

International Journal of Nuclear Security

The use of remote-controlled robots in emergency fields is a necessary requirement at present, which includes the nuclear engineering field because the radioactive environment creates adverse effects on human health. This work describes the development of a remotely controlled rover capable of detecting ionizing radiation, isolating radiation sources using a robotic arm, and sufficient shielding for its internal components. A custom-made Geiger–Muller counter has been used to detect ionizing radiation. The radioactive environment is not only harmful for humans but also can cause severe damage to the electronic circuit mounted on the robot. Therefore, a custom concrete material sandwiched between …

A Review And Analysis Of Nuclear Hydrogen Production In Generation Iv Reactors, Arijit Saha Ayon, Ashiqur Rahman Alif, A. S. M. Nasim

International Journal of Nuclear Security

Hydrogen is becoming increasingly vital as a chemical element in the progress of human civilization. Hydrogen finds application in the creation of ammonia, the manufacturing of nitrogen-based fertilizers, and a wide range of organic compounds, including methanol and propulsion fuel for space exploration missions. Additionally, there are ongoing experiments in the automotive industry to harness hydrogen-based fuel cells as an alternative power source. In modern technology, multiple methods and strategies for hydrogen production originate from diverse sources, such as fossil fuels, renewable energy, nuclear energy, and more. Generation IV nuclear reactors significantly affect the production of hydrogen. These reactors operate …

Bim Coordination Post Pandemic, Zachary Marshall

Honors Scholar Theses

The goal of this thesis is to utilize previous research done on virtual meetings and build upon it by conducting new research on the successes and failures of current virtual BIM meetings. This paper starts with a literature review looking into Building Information Modeling (BIM) Coordination and the effects the COVID-19 pandemic has had on the BIM meetings. BIM meetings started to shift virtual due to the nature of the pandemic and this has had effects on the performance and structure of the coordination. This knowledge was then expanded on by looking at virtual BIM meeting case studies. Interviews were …

Diegetic Sonification For Low Vision Gamers, Jhané Dawes

Master's Theses

There are not many games designed for all players that provide accommodations for low vision users. This means that low vision users may not get to engage with the gaming community in the same way as their sighted peers. In this thesis, I explore how diegetic sonification can be used as a tool to support these low vision gamers in the typical gaming environment. I asked low vision players to engage with a prototype game level with two diegetic sonification techniques applied, without the use of their corrective lenses. I found that participants had more enjoyment and experienced less difficulty …

Spatial Hearing In Simulated Reverberant Classroom Environments, Gabriel Seth Evan Weeldreyer

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

Spatial hearing provides access to auditory spatial cues that promote speech perception in noisy listening situations. However, reverberation degrades auditory spatial cues and limits listeners’ ability to utilize these cues for segregating target speech from competing babble. Hence, spatial unmasking—an intelligibility benefit from a spatial separation between a target and masker—is reduced in reverberant environments as compared to free field. This work tests the hypothesis that interaural decorrelation, the result of increasing reverberation, will broaden the perceived auditory source width with a cascading effect of reduced auditory spatial acuity and subsequently poorer spatial unmasking. To understand the perceptual consequences of …