Engineering Commons^™

The Mechanobiology Of Elbow Contracture: Pathogenesis And Prevention, Chelsey Dunham

McKelvey School of Engineering Graduate Student Theses & Dissertations

Post-traumatic elbow contracture is a multi-tissue pathology which develops in up to 50% of patients following elbow trauma (e.g., fracture, dislocation). It is unclear which periarticular soft tissues are driving the functional deficit following injury because it is not possible in clinical settings to isolate each soft tissues’ mechanical and biological contributions to elbow contracture. Therefore, an animal model is needed to identify the primary periarticular soft tissue(s) which contribute to contracture. The first animal models of contracture were developed in the knee; however, these studies are not generalizable to the elbow due to anatomical and functional differences between these …

Ultrafine Particle-Particle And Particle-Ion Interactions In Aerosol Reactors, Girish Sharma

McKelvey School of Engineering Graduate Student Theses & Dissertations

Aerosol science and technology has enabled the material synthesis of ‘good’ nanoparticles, as well as, addressed the problem of air pollution by developing particle capture technologies for ‘bad’ nanoparticles. For material synthesis at industrial scale, flame aerosol reactors are extensively used for large-scale industrial production of ‘good’ nanoparticles. But, there exists a knowledge gap in understanding the early stages (1-10 nm) of particle formation and growth, which is necessary for tailoring the synthesized nanoparticles’ properties. To achieve this goal, measurement tools for the characterization of 1-10 nm particles are quintessential. On the other hand, to capture ‘bad’ particles, existing control …

Joint Estimation Of Attenuation And Scatter For Tomographic Imaging With The Broken Ray Transform, Michael Ray Walker

McKelvey School of Engineering Graduate Student Theses & Dissertations

The single-scatter approximation is fundamental for many tomographic imaging problems. This class broadly includes x-ray scattering imaging and optical scatter imaging for certain media. In all cases, noisy measurements are affected by both local events and nonlocal attenuation. Related applications typically focus on reconstructing one of two images: scatter density or total attenuation. However, both images are media specific. Both images are useful for object identification. Knowledge of one image aides estimation of the other, especially when estimating images from noisy data.Joint image recovery has been demonstrated analytically in the context of the broken ray transform (BRT) for attenuation and …

Numerical Investigation Of Wind Turbine Airfoils Under Clean And Dusty Air Conditions, Siyuan Chen

McKelvey School of Engineering Graduate Student Theses & Dissertations

The focus of research in this thesis is on numerical simulation of airflow around wind turbine airfoils (S809, S814 and S1210) under both clean and dusty air conditions by using Computational Fluid Dynamics (CFD). The physical geometries of the airfoils and the meshing processes are completed in the ANSYS Mesh package ICEM. The simulations and post-processing are done by ANSYS FLUENT. For cases of clean air condition, Spalart–Allmaras (SA), realizable k-ε and Wray-Agarwal (WA) turbulence models are employed in the calculations. The results are compared with the experimental data for validation. For dusty air condition, simulation of the two-phase flow …

Cfd Analysis Of A Wind Turbine Airfoil With Flap, Heyou Tan

McKelvey School of Engineering Graduate Student Theses & Dissertations

The focus of this thesis is to evaluate the aerodynamic performance of NREL S809 airfoil (widely used airfoil for wind turbine blades) with a trailing-edge flap by numerical simulations. In the simulations, the geometry of the flap and the gap between the main element and the flap are varied. The airfoil geometry is created in Design Modeler and structured mesh around the airfoil is generated using meshing software ICEM. Simulations are performed using the Reynolds-Averaged Navier-Stokes (RANS) equations with SST k-ω, Spalart-Allmaras (SA) and Wray-Agarwal (WA) turbulence models at Reynolds number 106 at angles of attack of 0, 5o, 10o, …

The Role Of Gene Transcription And Inflammatory Cytokines In Bone Fracture Repair, Brandon Alan Coates

McKelvey School of Engineering Graduate Student Theses & Dissertations

In most instances, the skeleton has a remarkable capacity for repair following injury. However, in 5 to 10% of patients, fractures fail to properly heal resulting in non-union. A need exists for a more comprehensive understanding of the complex biology of fracture repair, which involves the coordinated work of many cell types including osteoblasts, osteoclasts, and immune cells. Depending on the extent of injury, fractures will heal through either intramembranous bone formation, involving the direct formation of bone callus, or endochondral bone formation, featuring a cartilage intermediary prior to bone callus formation. Both processes begin with inflammation, which sets the …

Development Of Novel Instrumentation And Methods To Investigate The Composition And Phase Partitioning Of Semivolatile And Intermediately Volatile Organic Compounds In Atmospheric Organic Aerosol, Claire Fortenberry

McKelvey School of Engineering Graduate Student Theses & Dissertations

Atmospheric particulate matter (PM) is ubiquitous in both indoor and outdoor air and is generally detrimental to human health. PM composed of particles with aerodynamic diameters less than 2.5 um (PM2.5) are related to adverse health outcomes including heart disease and respiratory disease. Fundamentally, particle physical properties such as size and hygroscopicity are dictated by chemical composition, which can be highly complex, particularly for organic aerosol (OA). In both outdoor and indoor air, OA is composed substantially of intermediately volatile and semivolatile organic compounds (I/SVOCs), which exist in both gas and particle phases under typical atmospheric conditions. The distribution of …

Scalable Synthesis Of Nanostructured Metal Oxide Films Using Aerosol Chemical Vapor Deposition For Energy Storage Applications, Clayton Kacica

McKelvey School of Engineering Graduate Student Theses & Dissertations

As global energy consumption continues to rapidly increase, the need for new technologies to meet this demand in a sustainable way. Renewable sources such as solar and wind power are being increasingly utilized for electricity generation. However, the intermittent nature of these sources requires large-scale energy storage to reliably provide consistent power. Current grid-scale energy storage usually involves pumped hydroelectric systems, which are limited by location, or flywheel systems, which have limited use in high-power low-energy applications. Electrochemical storage solutions, such as lithium-ion batteries, provide robust energy storage that is not limited by location with a range of power and …

Nucleation Dynamics For Water Condensation On Hydrophobic Surfaces In The Presence Of Non-Condensable Gases, Xinyu Jiang

McKelvey School of Engineering Graduate Student Theses & Dissertations

The density and rate of nucleation (here-in called nucleation density rate) significantly influences the heat transfer performance during dropwise condensation, as more than 70% of the total heat transfer happen for droplets smaller than 10 μm. Based on the classical nucleation theory, supersaturation strongly influences nucleation dynamics. However, the presence of non-condensable gas can strongly reduce the nucleation density rate by forming a vapor-depleted gas diffusion layer. Therefore, this work studied the relationship between nucleation density rate and supersaturation ratio during dropwise condensation on subcooled smooth hydrophobic surfaces with the presence of non-condensable gases in a custom-built condensation chamber. High-speed …

Ultrasensitive Biodetection Based On Plasmonically-Active Materials, Jingyi Luan

McKelvey School of Engineering Graduate Student Theses & Dissertations

A broad range of biomarkers continue to emerge as potentially important parameters for early detection of many pathological conditions.1 A disease biomarker (e.g. protein, a fragment of a pro-tein, DNA/RNA, or metabolites) is a ‘molecular signature’ of the physiological state of patient at specific time and is therefore extremely important for early and possibly pre-symptomatic diagno-sis and accurate monitoring of therapeutic intervention. Relevant concentrations of biomarkers related to diseases such as cancer, heart disease, inflammation, and neurological disorders can range in many orders of magnitude from μg/ml levels to sub-fg/ml, some of which possibly still remain unidentified due to the …

Nucleation Dynamics For Water Condensation On Hydrophobic Surfaces In The Presence Of Non-Condensable Gases, Xinyu Jiang

McKelvey School of Engineering Graduate Student Theses & Dissertations

The density and rate of nucleation (here-in called nucleation density rate) significantly influences the heat transfer performance during dropwise condensation, as more than 70% of the total heat transfer happen for droplets smaller than 10 μm. Based on the classical nucleation theory, supersaturation strongly influences nucleation dynamics. However, the presence of non-condensable gas can strongly reduce the nucleation density rate by forming a vapor-depleted gas diffusion layer. Therefore, this work studied the relationship between nucleation density rate and supersaturation ratio during dropwise condensation on subcooled smooth hydrophobic surfaces with the presence of non-condensable gases in a custom-built condensation chamber. High-speed …

Self Capacitance Based Wireless Power Transfer For Wearable Electronics: Theory And Implementation, Yarub Omer Alazzawi

McKelvey School of Engineering Graduate Student Theses & Dissertations

Wireless power transfer (WPT)

Quantitative Fluorescence Imaging For Investigation And Treatment Of Disease, Lemoyne Michael Habimana-Griffin

McKelvey School of Engineering Graduate Student Theses & Dissertations

Molecular imaging is a powerful tool that enables interrogation of basic molecular mechanisms, diagnosis of disease, guidance of therapeutic modalities and monitoring of treatment response. Among the various imaging modalities, optical imaging is particularly suited for preclinical molecular imaging owing to its high sensitivity, lack of exposure to ionizing radiation, low cost, portability and scalability of imaging from the microscopic to macroscopic scale. In particular, fluorescence molecular tomography (FMT) provides quantitative 3D reconstructions of fluorescence distributions down to picomole quantities allowing for whole animal molecular imaging. In this work, FMT is applied to detect disease-specific molecular probes, to monitor and …

Application Of Photoacoustic Imaging In Understanding Tissue Remodeling, Yuan Qu

McKelvey School of Engineering Graduate Student Theses & Dissertations

Photoacoustic Imaging (PAI) as an imaging method in biomedical research can provide high spatial resolution, various contrasts, great detection sensitivity, and deep penetration. These advantages are attributed to the combination of optical excitation and acoustic detection, which releases PAI from the ballistic limit faced by other optical imaging technique with high spatial resolution. In this dissertation, we aim to apply this technique to understand the connective tissue remodeling that is a ubiquitous physiological change in various medical complications.Chapter 1 elaborates the mechanism of PAI as well as the motivation of my dissertation.In Chapter 2, I introduce a new contrast mechanism …

Tissue Engineering Of Induced Pluripotent Stem Cells For The Development Of Novel Treatment Strategies For Osteoarthritis, Alison Ross

McKelvey School of Engineering Graduate Student Theses & Dissertations

Osteoarthritis (OA) is a debilitating joint disease that is primarily characterized by the degeneration of articular cartilage, the soft connective tissue that covers articulating bone surfaces in diarthrodial joints. While there are a number of risk factors for developing OA, the progression of this disease is mediated in part by pro-inflammatory cytokines from both the synovium and chondrocytes, the resident cells of articular cartilage. These cytokines, specifically interleukin 1 (IL-1) and tumor necrosis factor alpha (TNF-α), induce aberrant expression of catabolic and degradative enzymes and inflammatory cytokines in OA, which promotes degradation of engineered tissues as well as native articular …

Cognitive Radar Detection In Nonstationary Environments And Target Tracking, Yijian Xiang

McKelvey School of Engineering Graduate Student Theses & Dissertations

Target detection and tracking are the most fundamental and important problems in a wide variety of defense and civilian radar systems. In recent years, to cope with complex environments and stealthy targets, the concept of cognitive radars has been proposed to integrate intelligent modules into conventional radar systems. To achieve better performance, cognitive radars are designed to sense, learn from, and adapt to environments. In this dissertation, we introduce cognitive radars for target detection in nonstationary environments and cognitive radar networks for target tracking.For target detection, many algorithms in the literature assume a stationary environment (clutter). However, in practical scenarios, …

Chemistry Of Nanoscale Solids And Organic Matter In Sustainable Water Management Systems, Xuanhao Wu

McKelvey School of Engineering Graduate Student Theses & Dissertations

To alleviate global water scarcity and improve public health, engineered water treatment and management systems have been developed for purifying contaminated water and desalinating brackish or ocean water. These engineered systems provide substantial amounts of potable water and lessen environmental concerns about the release of contaminated water. Wastewater treatment plants (WWTPs), water desalination plants (WDPs), and managed aquifer recharge systems (MARs) are three representative sustainable water management (SWM) systems. But the operation of all three poses two fundamental questions: (1) What is the fate of nanoscale solids (e.g., engineered nanomaterials, naturally occurring nanoparticles) in SWM systems and how will their …

Cfd Analysis Of A Wind Turbine Airfoil With Flap, Heyou Tan

McKelvey School of Engineering Graduate Student Theses & Dissertations

The focus of this thesis is to evaluate the aerodynamic performance of NREL S809 airfoil (widely used airfoil for wind turbine blades) with a trailing-edge flap by numerical simulations. In the simulations, the geometry of the flap and the gap between the main element and the flap are varied. The airfoil geometry is created in Design Modeler and structured mesh around the airfoil is generated using meshing software ICEM. Simulations are performed using the Reynolds-Averaged Navier-Stokes (RANS) equations with SST k-ω, Spalart-Allmaras (SA) and Wray-Agarwal (WA) turbulence models at Reynolds number 10⁶ at angles of attack of 0^{o …}

Exploring Usage Of Web Resources Through A Model Of Api Learning, Finn Voichick

McKelvey School of Engineering Graduate Student Theses & Dissertations

Application programming interfaces (APIs) are essential to modern software development, and new APIs are frequently being produced. Consequently, software developers must regularly learn new APIs, which they typically do on the job from online resources rather than in a formal educational context. The Kelleher–Ichinco COIL model, an acronym for “Collection and Organization of Information for Learning,” was recently developed to model the entire API learning process, drawing from information foraging theory, cognitive load theory, and external memory research. We ran an exploratory empirical user study in which participants performed a programming task using the React API with the goal of …

Structure, Thermophysical Properties Of Liquids, And Their Connection With Glass Formability, Rongrong Dai

McKelvey School of Engineering Graduate Student Theses & Dissertations

Metallic glasses have drawn significant attention due to their unique properties, such as high strength, excellent elastic energy storage capacity, and versatile processability. However, why some liquids can easily form metallic glasses while others donմ is still unclear. Since metallic glasses are formed when liquids are cooled fast enough to bypass crystallization, we hope to better understand glass formation by investigating the structural evolution and thermophysical properties of the liquids as they are cooled toward the glass transition. Multiple molecular dynamics simulations suggest a crossover temperature for the dynamics near the liquidus temperature, which corresponds to the onset of cooperative …

First-Principles Studies Of Anion Engineering In Functional Ceramics, Steven Timothy Hartman

McKelvey School of Engineering Graduate Student Theses & Dissertations

Ceramic materials display a wide variety of valuable properties, such as ferroelectricity, superconductivity, and magnetic ordering, due to the partially covalent bonds which connect the cations and anions. While many breakthroughs have been made by mixing multiple cations on a sublattice, the equivalent mixed-anion ceramics have not received nearly as much attention, despite the key role the anion plays in the materials’ properties. There is great potential for functional ceramics design using anion engineering, which aims to tune the materials properties by adding and removing different types of anions in existing classes of ceramic materials. In this dissertation, I present …

Exploring Attacks And Defenses In Additive Manufacturing Processes: Implications In Cyber-Physical Security, Nicholas Deily

McKelvey School of Engineering Graduate Student Theses & Dissertations

Many industries are rapidly adopting additive manufacturing (AM) because of the added versatility this technology offers over traditional manufacturing techniques. But with AM, there comes a unique set of security challenges that must be addressed. In particular, the issue of part verification is critically important given the growing reliance of safety-critical systems on 3D printed parts. In this thesis, the current state of part verification technologies will be examined in the con- text of AM-specific geometric-modification attacks, and an automated tool for 3D printed part verification will be presented. This work will cover: 1) the impacts of malicious attacks on …

Applying Bayesian Techniques To The Optimization Of Parameterized Quantum Circuits, Arthur Rattew

McKelvey School of Engineering Graduate Student Theses & Dissertations

In this work, we explore the challenges faced when creating quantum algorithms for near-term quantum computers. We examine the characteristics of problems that are amenable to such advantage, and the limitations of existing approaches. Additionally, we explore the importance of the classical optimizer in the Variational Quantum Eigensolver (VQE), and propose a Bayesian method to optimally configure a single parameter in a given quantum circuit. Experimental testing confirms that our method is significantly more tolerant to noise than the existing analytical approach and its variants (p < 0.008).

Predicate Informed Syntax-Guidance For Semantic Role Labeling, Sijia Wang

McKelvey School of Engineering Graduate Student Theses & Dissertations

In this thesis, we consider neural network approaches to the semantic role labeling task in seman-tic parsing. Recent state-of-the-art results for semantic role labeling are achieved by combiningLSTM neural networks and pre-trained features. This work offers a simple BERT-based modelwhich shows that, contrary to the popular belief that more complexity means better performance,removing LSTM improves the state of the art for span-based semantic role labeling. This modelhas improved F1 scores on both the test set of CoNLL-2012, and the Brown test set of CoNLL-2005 by at least 3 percentage points.In addition to this refinement of existing architectures, we also propose …

Elicitation And Aggregation Of Data In Knowledge Intensive Crowdsourcing, Dohoon Kim

All Computer Science and Engineering Research

With the significant advance of internet and connectivity, crowdsourcing gained more popularity and various crowdsourcing platforms emerged. This project focuses on knowledge-intensive crowdsourcing, in which agents are presented with the tasks that require certain knowledge in domain. Knowledge-intensive crowdsourcing requires agents to have experiences on the specific domain. With the constraint of resources and its trait as sourcing from crowd, platform is likely to draw agents with different levels of expertise and knowledge and asking same task can result in bad performance. Some agents can give better information when they are asked with more general question or more knowledge-specific task …

A Virtual 4d Ct Scanner, Xiwen Li

All Computer Science and Engineering Research

4D CT scan is widely used in medical imaging. Images are acquired through phases. In this case, we can track the motion of organs such as heart. However, it also introduces motion artifacts. A lot of research focuses on remove these artifacts. It is difficult to acquire artifact data by a real CT scanner. In this project, we implement a virtual CT machine to simulate the real 4D CT scan. we also conduct experi- ments to check its clinical reality with respect to respiratory and heart motion parameters.

Centrality Of Blockchain, Zixuan Li

All Computer Science and Engineering Research

Decentralization is widely recognized as the property and one of most important advantage of blockchain over legacy systems. However, decentralization is often discussed on the consensus layer and recent research shows the trend of centralization on several subsystem of blockchain. In this project, we measured centralization of Bitcoin and Ethereum on source code, development eco-system, and network node levels. We found that the programming language of project is highly centralized, code clone is very common inside Bitcoin and Ethereum community, and developer contribution distribution is highly centralized. We further discuss how could these centralizations lead to security issues in blockchain. …

Solving Disappearance At Gastech With Visual Analytic Techniques, Saulet Yskak

All Computer Science and Engineering Research

We are living in a society, where images and charts speak louder than words. Therefore, information visualization plays a major role in solving complex problems since it provides a visual summary of data that makes it easier to identify trends and patterns.

In this master project, I propose a web – based visual analytics tool that enables to analyze complex email and time based / event series data. The visual analytics framework uses test data from IEEE VAST Challenge 2014: Mini challenge 1 that concentrated on the disappearance of employees of a fictional GAStech company, but the tool allows users …

Design And Validation Of A Dynamic Pressure-Based Loading Device And 3d Strain Tracking Protocol For Ventral Hernia Modeling, Griffin Kivitz

McKelvey School of Engineering Graduate Student Theses & Dissertations

It is estimated that 350,000-500,000 ventral hernia repair surgeries are performed each year in the United States. While the long-term recurrence rate of ventral hernia repairs is not yet known, when tissues are exposed to the trauma of surgery, there is always the chance of recurrence. Commonly used ex vivo testing methods for determining the mechanical properties of the abdominal wall and biomaterials for hernia repair consist primarily of uniaxial and biaxial testing, which are not physiologically relevant loading environments. The need for a testing device that can exert physiologically relevant loads ex vivo to an abdominal wall is crucial …

Toward Controlling Cardiac Tissue Pacing Using Modified Mrna, Yicheng Zhao

McKelvey School of Engineering Graduate Student Theses & Dissertations

Arrhythmia is a common heart disease that happens when the heart is beating too fast, too slow, or irregularly. To study the mechanisms and treatments of this disease, it is important to acutely control the beating rate of the model as it will help distinguish the contribution of different potassium currents and drug-induced action potential in cardiomyocytes. The current method of tissue pacing, electrical pacing, causes contamination and corrosive damage to tissues, thus the tissues fail to be used repeatedly or in future studies. In this study, red-shifted channelrhodopsin (ReaChR) is applied as a non-chemical means to control the beating …