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Theses and Dissertations

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Full-Text Articles in Engineering

Engineering And Optimization Of An Aav Based Viral Vector To Limit The In-Vitro Expression Of Sars-Cov-2 Spike-Protein, Ronald Anderson Smithwick Apr 2022

Engineering And Optimization Of An Aav Based Viral Vector To Limit The In-Vitro Expression Of Sars-Cov-2 Spike-Protein, Ronald Anderson Smithwick

Theses and Dissertations

Severe Acute Respiratory Syndrome Corona Virus-2, also known as SARS-CoV-2, is a newly emerged respiratory viral pathogen. The outbreak of SARS-CoV-2 started in Wuhan, China, in late 2019 and rapidly transformed into a pandemic. Several vaccines have been developed and are available to the public on an unprecedented timeline, protecting individuals from a severe infection and saving precious lives. However, none of the vaccines can provide a sterile immunity, and the SARS-CoV-2 transmission cycle continues. Additionally, because of the mutation-prone RNA genome and immunological selection pressure, SARS-CoV-2 is rapidly mutating, especially the Spike(S) protein, and new viral strains are arising …


First-Principles Based Heterogeneous Catalyst Design For Energy Conversion And Plastics Upcycling Processes, Kyung-Eun You Apr 2022

First-Principles Based Heterogeneous Catalyst Design For Energy Conversion And Plastics Upcycling Processes, Kyung-Eun You

Theses and Dissertations

Replacing scarce and expensive Pt-group metals (Pt, Pd, Ir, Rh, and Ru) commonly used in heterogeneous catalysis with earth-abundant and inexpensive materials is an important challenge to achieve sustainability

The main focus of the first project is to develop highly selective non-precious metal catalysts for the hydrodeoxygenation (HDO) of biomass-derived polyols and we chose to examine the HDO of glycerol and its deoxygenated reaction products (1,2- and 1,3- propanediol) over Cu modified Mo2C (Cu/Mo2C) catalysts. In this study, we combined experimental and density functional theory (DFT) results to reveal that the Cu modifier can significantly reduce …


Manufacturing Process Considerations When Transitioning From Thermoset To Thermoplastic Composite Material For Urban Air Mobility Propellers, Samuel Leonard Jones Iii Apr 2022

Manufacturing Process Considerations When Transitioning From Thermoset To Thermoplastic Composite Material For Urban Air Mobility Propellers, Samuel Leonard Jones Iii

Theses and Dissertations

Aerospace manufacturing has seen continually increased use of carbon fiber reinforced polymers in aircraft structures. The favorable strength to weight ratios, as well as the increased resistance to fatigue and corrosion, compared to metallic structures, provide a common argument for further research and development of composite airframes. Two main classes of carbon fiber reinforced polymers can be distinguished, thermosetting polymers and thermoplastic polymers. Thermoset polymers have been relied on for decades for the ability to reliably produce strong laminates for aircraft structures. By comparison thermoplastic polymers experience less comparable utilization on primary structures despite boasting similar or greater performance capabilities …


Fundamentals Of Adsorption And Large Scale Pressure Swing Adsorption (Psa) Process Design, Huan Jiang Apr 2022

Fundamentals Of Adsorption And Large Scale Pressure Swing Adsorption (Psa) Process Design, Huan Jiang

Theses and Dissertations

This work focused on both fundamental of adsorption and large-scale PSA design. Chapter 1 and 2 addressed the analysis of conditions for formation of adsorption azeotropes in binary systems. Chapter 1 theoretically assessed the necessary and sufficient conditions for the formation of an adsorption azeotrope in a binary gas mixture when this mixture exhibits either intersecting or non-intersecting single gas isotherms. Chapter 2 confirmed theoretically whether adsorption azeotropes can form in a binary mixture at a pressure below the intersection pressure of the corresponding single gas isotherms. Analytical expressions derived for both general and dual thermodynamically consistent process Langmuir (DPL) …


Classification Of Acoustic Emission Data Into Load Steps Using An Artificial Neural Network, Allen Ross Apr 2022

Classification Of Acoustic Emission Data Into Load Steps Using An Artificial Neural Network, Allen Ross

Theses and Dissertations

The average age of bridges in South Carolina is approaching 40 years, very close to the 50-year service life. Almost 11% of the bridges in South Carolina are rated as structurally deficient, greater than the national average of 7.5% (South 2021). Health monitoring is the concept that in-situ sensors can continuously monitor civil structures and send real time signals of damage. This process allows for automation and could save time and money on the inspection and load rating of bridges. Health monitoring requires sensors that provide uninterrupted data without sacrificing the functionality of the bridge. A prime candidate for this …


Interrogating The Role Of Ing4 In Hematopoietic Stem Cells And Cancer, Zanshé Thompson Apr 2022

Interrogating The Role Of Ing4 In Hematopoietic Stem Cells And Cancer, Zanshé Thompson

Theses and Dissertations

We recently identified the tumor suppressor, Ing4, as a critical regulator of hematopoietic stem cell (HSC) homeostasis. The mis-regulation of Ing4 in human cancers has also been shown to lend malignant cells specific advantages that support carcinogenesis and tumor progression. This activity is, in part, due to Ing4 mediated regulation of overlapping signaling pathways that regulate stem cell activity and cancer cells, including NF-B and c-Myc. In a two-part study, we have investigated the role of Ing4 in murine hematopoiesis and human malignancies. While the specific mechanisms of stem cell self-renewal, maintenance, and differentiation are poorly characterized, we have determined …


In Vitro And In Vivo Studies Of Mediator Kinase, Lili Wang Apr 2022

In Vitro And In Vivo Studies Of Mediator Kinase, Lili Wang

Theses and Dissertations

This project addresses the molecular and in vivo activities of transcriptionregulating module CKM, comprised of CDK8 (or CDK19) kinases, Cyclin C, MED12 and MED13. Our lab has found that CDK8/19 potentiates NFkB-induced transcription. In this study, we confirmed that both CDK8 and CDK19 regulate gene expression in kinasedependent manner. CDK8 and CDK19 are not required for NFkB-induced transcription, which also occurs in HEK293-dKO (CDK8 and CDK19 double knockout) cells, but such transcription becomes CDK8/19-dependent upon re-expression of CDK8 or CDK19 in dKO. Surprisingly. pre-treatment with a CDK8/19 inhibitor decreases the effect of CDK8/19 on NFkB-induced transcription.

In another set of …


Mechanistic Multiphysics Modeling Of Cladding Rupture In Nuclear Fuel Rods During Loss-Of-Coolant Accident Conditions, Kyle Allan Lawrence Gamble Apr 2022

Mechanistic Multiphysics Modeling Of Cladding Rupture In Nuclear Fuel Rods During Loss-Of-Coolant Accident Conditions, Kyle Allan Lawrence Gamble

Theses and Dissertations

The Loss of Coolant Accident (LOCA) is a design basis accident that is included as part of the safety analysis of nuclear power plants. As the nuclear industry desires to increase the cycle length and discharge burnup of existing nuclear power plants they must demonstrate safe operation during a LOCA on high burnup fuel. During a LOCA transient on high burnup fuel rods, the rods may undergo a process known as fuel fragmentation, relocation, and dispersal (FFRD). To permit dispersal, the cladding encapsulating the fuel must rupture with an opening size large enough to allow the fragmented fuel particles to …


The Submission Of A Section 513(G) Request For Information, Morgan Ashley Lano Apr 2022

The Submission Of A Section 513(G) Request For Information, Morgan Ashley Lano

Theses and Dissertations

The Food and Drug Administration designates all medical devices into one of three general classes contingent on their intended use, indications for use, and potential risk to the user. This classification dictates the further path the device must take to be approved for the commercial market. Section 513(g) of the Federal Food, Drug, and Cosmetic Act (21 U.S.C. 360c(g)) is submitted in order to gain the agency’s unofficial classification and suggested regulatory requirements. The Coagulation Companion (MicroVide) is a device designed to fluorescently quantify a key enzyme involved in the coagulation cascade, plasmin, in pediatric patients. clot formation and degradation …


Coalitional Game Theory For Stormwater Management And Green Infrastructure Practices, Carly Lawyer Apr 2022

Coalitional Game Theory For Stormwater Management And Green Infrastructure Practices, Carly Lawyer

Theses and Dissertations

As global warming and climate Variability bring about more frequent and intense rainstorms and accelerate sea level rise, our social and built environments are at heightened risk of flood induced damages and consequent costs. This is particularly true for coastal areas, facing the coupled effects of these threats while serving as home to people, businesses, unique landscapes, and historic landmarks. Complex decisions at all levels of government and community planning stand to benefit from increased understanding of possible outcomes and pathways resulting from decentralized human behavior and decision making in the realm of water resources engineering and management. Game theory …


Deep Learning Based Generative Materials Design, Yong Zhao Apr 2022

Deep Learning Based Generative Materials Design, Yong Zhao

Theses and Dissertations

Discovery of novel functional materials is playing an increasingly important role in many key industries such as lithium batteries for electric vehicles and cell phones. However experimental tinkering of existing materials or Density Functional Theory (DFT) based screening of known crystal structures, two of the major current materials design approaches, are both severely constrained by the limited scale (around 250,000 in ICSD database) and diversity of existing materials and the lack of a sufficient number of materials with annotated properties. How to generate a large number of physically feasible, stable, and synthesizable crystal materials and build accurate property prediction models …


Spydrnet - An Open-Source Python Netlist Representation For Analysis And Transformation, Dallin Mark Skouson Mar 2022

Spydrnet - An Open-Source Python Netlist Representation For Analysis And Transformation, Dallin Mark Skouson

Theses and Dissertations

SpyDrNet is an open-source structural netlist representation framework written in Python that allows users to create, analyze, and manipulate structural netlists. The internal format was designed to hold generic source structural netlists. Verilog and EDIF netlists generated by Vivado were read and written by SpyDrNet. Additional API functionality was built around the netlist representation. An application applying triple modular redundancy and duplication with compare was created and successfully used.


Design And Characterization Of A Novel Reverberation Chamber For Measuring Sound Transmission Loss In 3d Printed Multimaterials, Trigun Dinesh Maroo Mar 2022

Design And Characterization Of A Novel Reverberation Chamber For Measuring Sound Transmission Loss In 3d Printed Multimaterials, Trigun Dinesh Maroo

Theses and Dissertations

Acoustic localization of robots in indoor environments suffer from inevitable reverberation, for which, the use of unidirectional microphones as sensory receptors is preferred. While unidirectional microphones remain prohibitively expensive for ubiquitous usage, externally applying a custom structure around an inexpensive omnidirectional microphone can also grant it desired directionality. The structure can be fabricated via single or multimaterial 3D printing, and its effectiveness can be determined via its Sound Transmission Loss (STL). As an alternative to increasing thickness of a 3D printed single material structure, this research proposes the use of 3D printed multimaterial structures to achieve increased STL. The following …


U-Splines: Splines Over Unstructured Meshes, Steven K. Schmidt Mar 2022

U-Splines: Splines Over Unstructured Meshes, Steven K. Schmidt

Theses and Dissertations

U-splines are a novel approach to the construction of a spline basis for representing smooth objects in Computer-Aided Design (CAD) and Computer-Aided Engineering (CAE). A spline is a piecewise-defined function that satisfies continuity constraints between adjacent cells in a mesh. U-splines differ from existing spline constructions, such as Non-Uniform Rational B-splines (NURBS), subdivision surfaces, T-splines, and hierarchical B-splines, in that they can accommodate local variation in cell size, polynomial degree, and smoothness simultaneously over more varied mesh configurations. Mixed cell types (e.g., triangle and tetrahedron and quadrilateral and hexahedral cells in the same mesh) and T-junctions are also supported. The …


Towards Trojan Detection From A Raw Bitstream, Corey Ryan Simpson Mar 2022

Towards Trojan Detection From A Raw Bitstream, Corey Ryan Simpson

Theses and Dissertations

Many avenues exist to insert malicious circuitry into an FPGA designs, including compromised CAD tools, overwriting bitstream files, and post-deployment attacks. The proprietary nature of the Xilinx bitstreams precludes the ability to validate an implemented design. This thesis introduces the BitRec and IPRec projects in an effort to support trojan detection tools. BitRec provides a novel approach to mapping of the Xilinx bitstream format into FPGA features in order to recreate the original design's netlist. BitRec supports the 7 Series, UltraScale and UltraScale+ architectures. IPRec then provides a novel approach to recognizing parameterizable IP within a flattened netlist in an …


Standards-Compatible Smoke Points For Mono- And Un- Substituted Cycloalkane Fuel Components, Adekunle Vincent Adeniyi Mar 2022

Standards-Compatible Smoke Points For Mono- And Un- Substituted Cycloalkane Fuel Components, Adekunle Vincent Adeniyi

Theses and Dissertations

Emissions from the aviation industry have increased significantly over the decades and may continue to pose an environmental threat. Accordingly, efforts are being made to replace conventional aviation fuels with more sustainable alternatives that can both reduce net CO2 emissions as well as reduce other pollutants (i.e., particulates). Conventional jet fuels include aromatic species, which have high sooting tendency. Therefore, to reduce particulate emissions, the fuel aromatics content must be reduced. Cycloalkanes have potential for replacing aromatics content in jet fuel but, compared to other broad classes of chemical species that make up conventional and alternative jet fuel, there is …


The Effect Of Soot Models In Oxy-Coal Combustion Simulations, Kamron Groves Brinkerhoff Mar 2022

The Effect Of Soot Models In Oxy-Coal Combustion Simulations, Kamron Groves Brinkerhoff

Theses and Dissertations

Soot in coal combustion simulations is often ignored due to its computational complexity, despite significant effects on flame temperature and radiation. In this research, a 40 kW oxy-coal combustion system is modeled using Large Eddy Simulations (LES) and a semi-empirical monodisperse coal soot model. Simulation results are compared to experimental measurements of temperature, species concentrations, and soot concentration. Cases where soot is modeled are compared with cases where soot is neglected to determine the accuracy benefits of modeling soot. The simulations were able to replicate experimental results within an acceptable level of error. Including soot in the simulations did not …


Multipath Mitigation In Frequency Selective Channels With An Emphasis On 5g Cellular Mobile Networks And Aeronautical Mobile Telemetry Applications, Farah Arabian Mar 2022

Multipath Mitigation In Frequency Selective Channels With An Emphasis On 5g Cellular Mobile Networks And Aeronautical Mobile Telemetry Applications, Farah Arabian

Theses and Dissertations

This dissertation explores the role of polarization, combining, and equalization operating over frequency-selective channels to improve the reliability of wireless communications systems in terms of BER for two applications: 5G mobile networks (operating in the mmWave band and NR FR1), and aeronautical mobile telemetry systems (operating in L band). The equivalent discrete-time models for a variety of spatial combining techniques at 5G mmWave bands were derived to investigate the performance of co-located cross-polarized antenna elements when polarization diversity is used and also when a combination of spatial and cross-polarized antennas is exploited. In both cases, ML combining has the lowest …


Managing Radio Frequency Interference In Vehicular Multi-Antenna Transceivers, Jakob W. Kunzler Mar 2022

Managing Radio Frequency Interference In Vehicular Multi-Antenna Transceivers, Jakob W. Kunzler

Theses and Dissertations

Radio frequency interference is an ever growing problem in the wireless community. This dissertation presents methods to reduce interference for vehicular multi-antenna devices. This document is organized into two parts: the main chapters and the appendices. The main chapters present research conducted primarily by the author. These deserve the reader's primary attention. The appendices showcase contributions made by the author serving in a supporting role to projects led by others and/or do not fit the vehicular theme. These should receive secondary attention. The main chapter contributions are summarized as follows. A device was created that provides over 105 dB of …


Exploratory Measurement Of Recession Rates Of Low Temperature Ablators Subjected To Mach 6 Flow, Ross H. Kellet Mar 2022

Exploratory Measurement Of Recession Rates Of Low Temperature Ablators Subjected To Mach 6 Flow, Ross H. Kellet

Theses and Dissertations

The high speed/high-temperature effect of heat shield ablation was simulated in the low-enthalpy AFRL Mach 6 Ludwieg Tube using solid dry ice as a low-temperature sublimator. The experiments utilized both 21 half-angle cones and bi-conic models with a 7 ° half-angle leading edge followed by a 26° half-angle base contained within a cryogenic-cooled stainless steel holder. A method of fabricating dry ice test articles was developed using commercially procured dry ice and custom-made aluminum molds. Tests were performed at Mach 6.1 with a stagnation temperature of 490 K and stagnation pressures ranging from 40 - 500 psi. Unit Reynolds number …


Effects Of Cone Tip Changes On Wall-Cooled Hypersonic Boundary Layer Transition And Turbulence, Mathew M. Major Mar 2022

Effects Of Cone Tip Changes On Wall-Cooled Hypersonic Boundary Layer Transition And Turbulence, Mathew M. Major

Theses and Dissertations

Boundary layer measurements took place at Air Force Research Lab’s (AFRL) Mach-6 Ludwieg tube hypersonic wind tunnel on a 7-degree half angle spherically blunted nose cone with a 1.5 mm radius to study the effects of a cooled surface on the transition process. Experiments compared uncooled and cooled flow conditions on the blunt-nosed model, and then compared to past data for a sharp-tipped cone of similar geometry. Cooling the surface delayed the onset of transition on the blunt nose model. Combining the effects of nose blunting and cooling further increased transition delay than each acting individually compared to the sharp-tipped …


Magnetic Flux Channel Antenna Design In Conformal Applications, William J. Tremblay Mar 2022

Magnetic Flux Channel Antenna Design In Conformal Applications, William J. Tremblay

Theses and Dissertations

Magnetic Flux Channels (MFC) and Magneto-Dielectric Wire Antennas (MDWA) are effective, and in some cases, superior alternatives to traditional metallic antennas, in conformal and electrically small applications at the cost of fabrication and feed complexity. The frequency dispersive nature of magnetic material constituent parameters imposes constraints on the antenna design process, which were not fully developed in prior art. This research quantifies the key differences between the operating regions of magneto-dielectric materials for antenna applications and demonstrates the effectiveness of numerical method augmented modal analysis in the design process, regardless of operating region. Modeling challenges associated with MDWAs are addressed …


Manufacturing Of A Ceramic Turbine Rotor For A Compact Jet Engine, Bryan T. Leicht Mar 2022

Manufacturing Of A Ceramic Turbine Rotor For A Compact Jet Engine, Bryan T. Leicht

Theses and Dissertations

The primary goal of this study was to develop a low-cost, timely, scalable manufacturing method that produced a ceramic turbine that can be tested as a drop-in replacement on a JetCat P400 small scale gas turbine engine. This research compared two processes for manufacturing a ceramic turbine utilizing a pour casting method and 3D printing using stereolithography ceramic manufacturing (SLCM). The pour casting method used Silicon Nitride to create a cast turbine using a sacrificial 3D printed mold. The SLCM method evaluated producing an alumina turbine using an ADMATEC Admaflex 300 SLCM printer to directly print a ceramic turbine. This …


Magnetic Anomaly Absolute Positioning For Hypersonic Aircraft, Alexander J. Mcneil Mar 2022

Magnetic Anomaly Absolute Positioning For Hypersonic Aircraft, Alexander J. Mcneil

Theses and Dissertations

GPS has proven to be an extremely valuable asset for navigation, and timing. GPS has become the standard navigation system for all applications, but GPS has limitations. GPS is susceptible to jamming, spoofing, and in the case of hypersonic aircraft, is likely unavailable. When an aircraft is traveling at hypersonic speeds, there is a plasma sheath that surrounds the aircraft. This plasma sheath blocks electromagnetic waves, and is therefore responsible for a GPS blackout. GPS unavailability for hypersonic aircraft has prompted the research into the viability of alternate navigation systems for these aircraft. This paper seeks to explore the viability …


Design Study For An Antenna Radar Cross Section Measurement Test Fixture, Wayne C. Kreimeyer Mar 2022

Design Study For An Antenna Radar Cross Section Measurement Test Fixture, Wayne C. Kreimeyer

Theses and Dissertations

Military technology requires equipment to be undetected by adversaries. Stealth aircraft are designed to be undetected through electromagnetic means by minimizing a return signature called the RCS. Therefore, it is essential to understand how antennas, which are necessary for communication, affect the overall RCS of the aircraft. The antenna is measured in a compact RADAR range. The antenna needs a structure to support it, also referred to as a test fixture, that does not interfere with the measuring process of the antenna’s RCS. This thesis set out to get the lowest RCS possible of a test fixture by evaluating different …


Deep Learning Approach To Multi-Phenomenological Nuclear Fuel Cycle Signals For Nonproliferation Applications, Preston J. Dicks Mar 2022

Deep Learning Approach To Multi-Phenomenological Nuclear Fuel Cycle Signals For Nonproliferation Applications, Preston J. Dicks

Theses and Dissertations

In order to reduce the time required for data analysis and decision-making relevant to nuclear proliferation detection, Artificial Intelligence (AI) techniques are applied to multi-phenomenological signals emitted from nuclear fuel cycle facilities to identify non-human readable characteristic signatures of operations for use in detecting proliferation activities. Seismic and magnetic emanations were collected in the vicinity of the High Flux Isotope Reactor (HFIR) and the McClellan Nuclear Research Center (MNRC). A novel bi-phenomenology DL network is designed to test the viability of transfer learning between nuclear reactor facilities. It is found that the network produces an 84.1% accuracy (99.4% without transient …


Utilization Of Characteristic Modal Analysis For Antenna Design Needed For An Afit Satellite, Scott C. Podlogar Mar 2022

Utilization Of Characteristic Modal Analysis For Antenna Design Needed For An Afit Satellite, Scott C. Podlogar

Theses and Dissertations

Antenna design is a pervasive, growing field for electrical engineers. As the number of new materials and techniques increase so too does the demand and requirements pushing forth new innovative ideas. Among these ideas is a leading edge analytic technique called Characteristic Modal Analysis (CMA) originally credited to Garbacz and Turpin. CMA works to break down the current distribution along a structure in a way that can offer great insights into how that structure operates as an antenna. This technique has great merits in post design analytics but it is rarely seen to be integrated into the design process. This …


Identifying Characteristics For Success Of Robotic Process Automations, Charles M. Unkrich Mar 2022

Identifying Characteristics For Success Of Robotic Process Automations, Charles M. Unkrich

Theses and Dissertations

In the pursuit of digital transformation, the Air Force creates digital airmen. Digital airmen are robotic process automations designed to eliminate the repetitive high-volume low-cognitive tasks that absorb so much of our Airmen's time. The automation product results in more time to focus on tasks that machines cannot sufficiently perform data analytics and improving the Air Force's informed decision-making. This research investigates the assessment of potential automation cases to ensure that we choose viable tasks for automation and applies multivariate analysis to determine which factors indicate successful projects. The data is insufficient to provide significant insights.


Analysis Of Microscopic Carbon Fiber Fragments, Zachary R. Scott Mar 2022

Analysis Of Microscopic Carbon Fiber Fragments, Zachary R. Scott

Theses and Dissertations

Carbon Fiber (CF) has different tensile strengths and transverse moduli depending on how they are fabricated. Some CF is export controlled as it can be used for weapons, spacecraft, or gas centrifuges for enriching nuclear fuel. This research project explored a new way to prepare micron sized single CF threads to measure their transverse modulus and compare the moduli of non-export controlled CF to that of an export controlled CF. Five total polyacrylonitrile (PAN) fibers were used in this project, one of which was an export controlled fiber.


Burn Probability And Climate Change: A Quantitative Evaluation Of The Temporal Alterations Of Wildfire, David N. Robinson Mar 2022

Burn Probability And Climate Change: A Quantitative Evaluation Of The Temporal Alterations Of Wildfire, David N. Robinson

Theses and Dissertations

The intensity of extreme weather events, specifically wildfires, along the West Coast has slowly grown overtime due to atmospheric changes caused by climate change. The Air Force, though aware of the threat that is wildfire, does not currently have a quantitative way to assess the hazard to base locations. In this paper, burn probability is quantitatively calculated through the geospatial analysis programs to provide a means of assessing wildfire vulnerability. The FlamMap fire simulator generated burn probabilities for Vandenberg Air Force Base using climate data generated by the remote automated weather station on the base to highlight how the burn …