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Characterizing The Editing Modes Of Duplicated Leucyl-Trna Synthetases In The Archaea Sulfolobus Islandicus, Evan T. Strandquist Mar 2023

Characterizing The Editing Modes Of Duplicated Leucyl-Trna Synthetases In The Archaea Sulfolobus Islandicus, Evan T. Strandquist

Theses and Dissertations

Aminoacyl-transfer RNA synthetases (aaRSs) catalyze the attachment of an amino acid to the 3’-end of a cognate tRNA in a two-step reaction, fulfilling a pivotal role in RNA translation by providing “charged” tRNA for protein synthesis. Synthetases possess a catalytic core where amino acids are activated via adenylation with the subsequent transfer of that activated amino acid to the acceptor adenosine at position 76 of the tRNA sequence.1,2 The fidelity of tRNA aminoacylation is essential for faithful protein synthesis and requires the aaRS to discriminate against chemically and structurally similar amino acids, though some studies suggest that aaRS-dependent errors can …

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Sources Of Atmospheric Dust Deposition On Utah Lake, Justin Telfer Mar 2023

Sources Of Atmospheric Dust Deposition On Utah Lake, Justin Telfer

Theses and Dissertations

Atmospheric deposition (AD) is a significant source of nutrient loading to waterbodies around the world. However, the sources and loading rates are poorly understood for major waterbodies and even less understood for local waterbodies. Utah Lake is a eutrophic lake located in central Utah, USA, and has high nutrient levels. Recent research has identified AD as significant sources for nutrient loading to the lake to better understand the dust AD sources, we sampled suspected source locations and collected deposition samples around the lake. We analyzed these samples using Inductively Coupled Plasma (ICP) for 25 metals to characterize their elemental fingerprints. …

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Role Of The Cytosolic Chaperonin Cct In The Folding Of Novel Substrates, Theresa M. Smith Mar 2023

Role Of The Cytosolic Chaperonin Cct In The Folding Of Novel Substrates, Theresa M. Smith

Theses and Dissertations

All cells depend on properly folded proteins for survival and function. Misfolding of proteins results in loss of critical functions and may trigger the misfolding of other nearby proteins leading to toxic aggregation. While many proteins can fold on their own, others with complicated domain structures require assistance from protein folding machines called chaperones. The most complex and highly specialized of all chaperones is the eukaryotic chaperonin complex CCT which is necessary for the folding of a wide variety of essential proteins. These include the cytoskeletal proteins actin and tubulin as well as the Gβ subunit of the G protein …

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Evolving Literacy Practices In The Vocational-Technical High School Classroom: How Critical Literacy Frameworks Enhance Learning And Increase Student Reading Success In Cte, Alice A. Infranco Mar 2023

Evolving Literacy Practices In The Vocational-Technical High School Classroom: How Critical Literacy Frameworks Enhance Learning And Increase Student Reading Success In Cte, Alice A. Infranco

Theses and Dissertations

This paper provides a qualitative account of how Critical Literacy instruction fosters reading growth in vocational-technical school settings. This study examines how critical literacy enriches learning outcomes within Career and Technical Education (CTE). The findings are that Critical Literacy skills are necessary for all readers because they positively affect student engagement and participation in learning, especially if presented in a way that allows students to have an active role in their learning. Examples of how to integrate Critical Literacy instruction into CTE classrooms are presented and discussed. These instructional practices go beyond traditional reading comprehension skills. The conclusion is that …

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Kif3 A Tail Domain Phosphorylation Is Not Required For Ciliogenesis In Mouse Embryonic Fibroblasts, Ayoola Fasawe Mar 2023

Kif3 A Tail Domain Phosphorylation Is Not Required For Ciliogenesis In Mouse Embryonic Fibroblasts, Ayoola Fasawe

Theses and Dissertations

Cilia and flagella are microtubule-based organelles that protrude from the plasma membrane of most cells in the body and play a critical role in cell signaling, motility, and development. Numerous diseases, collectively known as ciliopathies, with phenotypes like developmental abnormalities, cystic kidney disease, and obesity, have been linked to ciliary dysfunction. Intraflagellar transport (IFT) shuttles cellular cargoes along axonemal microtubules and into and out of cilia. IFT is essential for the assembly of cilia and flagella and is powered by heterodimeric kinesin-2 (KIF3A/KIF3B) and dynein-2. While the essential role of kinesin-2 in mammalian ciliogenesis is well established, little is known …

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Assessment Of Largemouth Bass (Micropterus Salmoides) Condition Using Liver Histopathology, Health Parameters And Water Quality Of The Central Chattahoochee River Watershed, Kari Carmack Goodwin Mar 2023

Assessment Of Largemouth Bass (Micropterus Salmoides) Condition Using Liver Histopathology, Health Parameters And Water Quality Of The Central Chattahoochee River Watershed, Kari Carmack Goodwin

Theses and Dissertations

The health of Largemouth bass from west-central Georgia was assessed using liver histopathology and the degree of tissue change index (DTC), hepatosomatic indices (HSI), relative weight, condition factors, and intersex. These health parameters as well as water chemistry data were compared across four bodies of water, three within the Chattahoochee watershed, and one pseudo-control located in the Flint watershed. Fish from Lake Oliver, Lake Harding, and West Point Lake had severely impacted liver health compared to Warm Springs National Fish Hatchery, with DTC rankings over 100 for the three lakes within the Chattahoochee watershed, demonstrating severely damaged livers. There was …

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Multi-Year Analysis Of Groundwater Temperature Fluctuations In A Shallow Aquifer Sysytem Influenced By A Tile-Drain, Jack Thomas Wassik Mar 2023

Multi-Year Analysis Of Groundwater Temperature Fluctuations In A Shallow Aquifer Sysytem Influenced By A Tile-Drain, Jack Thomas Wassik

Theses and Dissertations

Groundwater temperature plays a significant role in regulating geochemical, biological and physical processes with the subsurface with wide ranging environmental and societal impacts. Air temperature, weather conditions and lithology exhibit control on magnitude and timing of thermal responses that ultimately control groundwater temperature. Historical groundwater, tile water, stream and air temperature data from the T3 site were analyzed, including groundwater temperature data from multiple depths was analyzed. Additionally, statistical analyses between the temperature datasets were performed in order to interpret potential relationships. Air temperature was found to be the primary control of groundwater temperatures, though its affect being muted as …

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Influence Of Dilute Silicon Carbide Nanoparticle Additions To The Microstructure And Mechanical Properties Of Laser Powder Bed Fusion Molybdenum, Nathan E. Ellsworth Mar 2023

Influence Of Dilute Silicon Carbide Nanoparticle Additions To The Microstructure And Mechanical Properties Of Laser Powder Bed Fusion Molybdenum, Nathan E. Ellsworth

Theses and Dissertations

Consolidation of pure molybdenum through laser powder bed fusion and other additive manufacturing techniques is complicated by a high melting temperature, thermal conductivity, and ductile-to-brittle transition temperatures. Nano-sized silicon carbide particles (0.1 wt%) were homogeneously mixed with molybdenum powder and the printing characteristics, chemical composition, microstructure, and mechanical properties were compared to pure molybdenum for scan speeds of 100, 200, 400, and 800 mm/s. The addition of silicon carbide improved the consolidation and mechanical properties and the oxygen content was reduced. Two mechanisms of oxygen reduction were identified as responsible for the improvements: oxidation of free carbon and the creation …

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Estimation Of Optimal Flight Trajectory In A Total Power Loss Scenario Using Proximal Policy Optimization, Eidahn Eliash Mar 2023

Estimation Of Optimal Flight Trajectory In A Total Power Loss Scenario Using Proximal Policy Optimization, Eidahn Eliash

Theses and Dissertations

Recent research has been conducted in using deep reinforcement learning algorithms to generate closed form optimal control laws for helicopters in power loss scenarios. The control laws could allow for design of various cockpit visual pilot aids if proven successful. Such pilot aids are predicted to reduce pilot workload during execution of an emergency powerless landing, and to overall increase the probability of landing safely in such an event. The proposed topic discusses the use of the PPO algorithm in order to find an optimal control policy for a helicopter in a total power loss emergency landing scenario. The task …

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Garbage In ≠ Garbage Out: Exploring Gan Resilience To Image Training Set Degradations, Nicholas M. Crino Mar 2023

Garbage In ≠ Garbage Out: Exploring Gan Resilience To Image Training Set Degradations, Nicholas M. Crino

Theses and Dissertations

Generative Adversarial Networks (GANs) have received increasing attention in recent years due to their ability to capture complex, high-dimensional data distributions without the need for extensive labeling. Since their conception in 2014, a wide array of GAN variants have been proposed featuring alternative architectures, optimizers, and loss functions with the goal of improving performance and training stability. While this research has yielded GAN variants robust to training set shrinkage and corruption, our research focuses on quantifying the resilience of a GAN architecture to specific modes of image degradation. We conduct systematic experimentation to determine empirically the effects of 10 fundamental …

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Bayesian Recurrent Neural Networks For Real Time Object Detection, Stephen Z. Kimatian Mar 2023

Bayesian Recurrent Neural Networks For Real Time Object Detection, Stephen Z. Kimatian

Theses and Dissertations

Neural networks have become increasingly popular in real time object detection algorithms. A major concern with these algorithms is their ability to quantify their own uncertainty, leading to many high profile failures. This research proposes three novel real time detection algorithms. The first of leveraging Bayesian convolutional neural layers producing a predictive distribution, the second leveraging predictions from previous frames, and the third model combining these two techniques together. These augmentations seek to mitigate the calibration problem of modern detection algorithms. These three models are compared to the state of the art YOLO architecture; with the strongest contending model achieving …

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Designing A Counter-Iads Drone Swarm: Using Evolution To Evaluate Combat Assumptions Underpinning Drone Swarm Target Assignment, Olin H. Kennedy Mar 2023

Designing A Counter-Iads Drone Swarm: Using Evolution To Evaluate Combat Assumptions Underpinning Drone Swarm Target Assignment, Olin H. Kennedy

Theses and Dissertations

The original research goal was to combine the best techniques in the drone swarm literature and model a functional combat drone swarm that conducts a Suppression of Enemy Air Defense (SEAD) mission. However, the body of literature regarding Drone Swarm Target Assignment (DSTA) does not model enemy counteraction and assumes that the drones’ targets are compliant against destruction. Therefore, a model of enemy counteraction against drone swarms is developed, and Novel DSTA (NDSTA) is proposed to respond to the weaknesses of the current DSTA. Both methods of target assignment are combined with a tunable trajectory generation model, and the performance …

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What Black Students Need From White Teachers: A Qualitative Inquiry, Renee Sherie Andrews Mar 2023

What Black Students Need From White Teachers: A Qualitative Inquiry, Renee Sherie Andrews

Theses and Dissertations

Black high school students who attend majority-white schools are educated in environments that are contradictory to their cultural backgrounds. Because the teachers at these high schools tend to be mostly white, Black students in these environments t typically feel a lack of connection or that they do not belong. In this qualitative study, I explored the relationships between Black students and their white teachers. Data sources for this study included interviews of both Black students and their teachers. From the data, I found that Black high school students need the following from their teachers: (1) check in on them regularly; …

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Investigating Heterologous Transgene Expression In N. Crassa, James Christopher Mierendorf Mar 2023

Investigating Heterologous Transgene Expression In N. Crassa, James Christopher Mierendorf

Theses and Dissertations

First adopted as a model organism by Shear and Dodge in 1927, the filamentous fungus Neurospora crassa is among the most well studied eukaryotic systems today, facilitating major discoveries in genetics, biochemistry, and molecular biology. The sequencing of the Neurospora genome was completed in 2003, which combined with the organism’s fast growth, simple culturing requirements, and haploid life cycle, make it a particularly attractive model system. Despite these advantages, Neurospora crassa’s research value is diminished by its recalcitrance to expressing ectopic sequences incorporated into its genome. As a result, molecular techniques requiring heterologous expression (such as CRISPR) are largely incompatible …

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The Aerial Refueling Asset Basing And Assignment Problem, Camryn E. Deames Mar 2023

The Aerial Refueling Asset Basing And Assignment Problem, Camryn E. Deames

Theses and Dissertations

With growing tensions in the European theatre and Indo-Pacific theatre, the constraints of aerial refueling impede the missions of Air Mobility Command and USTRANSCOM in their execution of both the National Security Strategy and National Defense Strategy. Introducing and integrating semi-autonomous aerial refueling aircraft is a logical next step due to advantages in endurance, survivability, runway requirements, and fuel offloading capacity. This research frames the Aerial Refueling Asset Basing and Assignment Problem with two model approaches: a baseline model and a fuel shuttle concept model. Whereas the former model considers instances with only manned refuelers or only semi-autonomous refuelers, the …

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Student Performance In Traditional In-Person Vs. Online Sections Of An Introductory Graduate Mathematics Course, Lauran E. Kittle Mar 2023

Student Performance In Traditional In-Person Vs. Online Sections Of An Introductory Graduate Mathematics Course, Lauran E. Kittle

Theses and Dissertations

The growth of technology impacts nearly every aspect of everyday life, to include education and learning. The availability of distance learning (online) classes has increased drastically in the last few decades, expanding access to education for millions of people. However, it is imperative to consider exactly how the growth of technology impacts education – whether it is a positive, negative, or neutral impact. Previous research comparing distance learning and in-residence (traditional) classes have widely mixed, disparate conclusions. This type of research, two-stage analysis, and modeling has yet to be conducted on a graduate school level. For this reason, a detailed …

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Topological Variability In Water Distribution Networks, James M. Anderson Mar 2023

Topological Variability In Water Distribution Networks, James M. Anderson

Theses and Dissertations

Water distribution networks are critical infrastructure characterized by difficulties in their assessment and deteriorating performance due to aging components. Resilience analysis of networked infrastructure has replaced traditional risk analysis to focus on performance. Global Resilience Analysis can provide useful information to decision makers and system managers regarding repair and expansion of networks. Network performance has been found to be directly informed by network structure. This work leverages graph theory to assess network qualities that correlate with resiliency characteristics across 69 real world water networks. These networks are then grouped by their structural properties through k-means clustering and compared using parametric …

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The Kinetics Of Biocontaminant Inactivation: A Comparative Study With Bacillus Globigii And Bacillus Anthracis, Leigh M. Durden Mar 2023

The Kinetics Of Biocontaminant Inactivation: A Comparative Study With Bacillus Globigii And Bacillus Anthracis, Leigh M. Durden

Theses and Dissertations

Bacillus anthracis has been a biological threat for decades and after the 2001 terrorist attack via the U.S. Postal Service where five people died, there was heightened awareness and inquiry on the subject (Goel, 2015; Greenberg et al., 2010; Nicholson & Galeano, 2003; Spotts Whitney et al., 2003). The health risk to humans makes this biological agent, a Tier 1 agent and one of the most likely to be used in an attack (Anthrax as a Bioterrorism Weapon | CDC, n.d.; Driks, 2009; Rose & Rice, 2014). B. anthracis is one of most resistant and potent biological warfare agents as …

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Civilian And Military Civil Engineer Mission In The Space Domain, Linda E. Kuster Mar 2023

Civilian And Military Civil Engineer Mission In The Space Domain, Linda E. Kuster

Theses and Dissertations

Military and civil interest in space-based operations has increased dramatically in recent years due to the discovery of life sustaining properties such as water on Mars and advancements in cyber technology. Civilian sector discussions and research have centered on the establishment of permanent extraterrestrial infrastructure, while discussions from the military perspective have focused on providing reliable, resilient infrastructure, capable of withstanding cyber-based and kinetic attacks. Both perspectives account for known threats and sustainment methods required to ensure success in the space domain. With the existence of threats for the military and civilian missions, civil engineers will undoubtedly be critical to …

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The Effects Of Introversion And Treatment Delivery Modality On Therapeutic Outcomes In A Community Mental Health Clinic, Maria Olga Consbruck Mar 2023

The Effects Of Introversion And Treatment Delivery Modality On Therapeutic Outcomes In A Community Mental Health Clinic, Maria Olga Consbruck

Theses and Dissertations

Objective: The present study examines the effectiveness of teletherapy services for individuals with varying levels of introversion. This study also investigates the comparability of teletherapy to in-person services provided by clinicians in training. Introduction: Virtual platforms, such as teletherapy, have exponentially increased in use by clinicians and community members due to the Covid 19 pandemic. The pandemic has illuminated surprising secondary benefits of teletherapy. Research has shown that teletherapy results in greater accessibility, feasibility, and acceptability of treatment. Teletherapy platforms can reach remote and rural communities, and better address financial and time barriers. Current research indicates that teletherapy services are …

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Classification And Analysis Of Twitter Bot And Troll Accounts, Callan P. Mccormick Mar 2023

Classification And Analysis Of Twitter Bot And Troll Accounts, Callan P. Mccormick

Theses and Dissertations

This research trains, tests, and analyzes bot and troll classification models using publicly available, open source datasets. Specifically, it applies decision tree, random forest, feed forward neural networks, and long-short term memory neural networks with hyperparameters tuned via designed experiment to five labeled bot datasets created between 2011 and 2020 and one dataset labeling state-sponsored disinformation accounts or trolls. The first three models utilize account profile features, while the last model applies natural language processing techniques, specifically GloVe embedding, to analyze a user’s Tweet history. Results indicate that the random forest model outperforms the other three models with an average …

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Effects Of Occupationally Military-Relevant Particle Mixtures (Sio2, Cdo, Cr2O3) On A549 Human Pulmonary Epithelial Cells, Isabella M. Muffoletto Mar 2023

Effects Of Occupationally Military-Relevant Particle Mixtures (Sio2, Cdo, Cr2O3) On A549 Human Pulmonary Epithelial Cells, Isabella M. Muffoletto

Theses and Dissertations

In the course of maintaining a safe, mission-ready aircraft fleet and operational runways, United States Airmen experience a range of occupational risks. These risks include inhalable hazards generated from oft-used maintenance practices, such as blasting which emits silica from the media abrasives as well as contaminants from the exterior coatings. Additional inhalation hazards range from engine and fuel emissions, chemical agents, radiation, and explosives, to naturally occurring and human-manufactured biopathogens. Of notable concern are emissions in forward-deployment areas, including urban pollution, particulates released from runway construction and maintenance activities, and combustion from burn pits containing hazardous and unknown combinations of …

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Induced Correlation And Its Effects In The Performance Of Fused Classification Systems, Mary K. Collins Mar 2023

Induced Correlation And Its Effects In The Performance Of Fused Classification Systems, Mary K. Collins

Theses and Dissertations

Classification systems are abundant in modern-day life. The United States Air Force uses classification systems across many applications such as radar, satellite, and infrared sensing just to name a few. Combining classification systems allows an opportunity to get more accurate results. Using the known information from already built and tested systems that can be mathematically combined can give insight into the performance of the fused system without having to build a combined system. Leveraging this can save time, resources, and money. This work examines the correlation effects of fusing two classifier systems, each with only two labels, using the Boolean …

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Modeling Radiation Exposure On Flight Missions To Analyze Aircrew Risk, Camila V. Quintero Hilsaca Mar 2023

Modeling Radiation Exposure On Flight Missions To Analyze Aircrew Risk, Camila V. Quintero Hilsaca

Theses and Dissertations

GCR and SPE comprise the majority of the ionizing radiation experienced in the upper atmosphere within flight-altitude environments. Although previous studies have analyzed radiation doses from single sources on civilian flight operations, there is a lack of research focused on dose received by military personnel during flight from both sources simultaneously. In-flight radiation environments are modeled through the MCNP6 for two separate aircraft, an Air Force A-10 and a Boeing 737. Particle fluence values for galactic cosmic rays and solar particle events for four separate flight paths are determined using the CARI-7A software and the SIRE2 toolkit, respectively. MCNP6 code …

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Cellphone-Acoustics Based Suas Detection And Tracking, Ryan D. Clendening Mar 2023

Cellphone-Acoustics Based Suas Detection And Tracking, Ryan D. Clendening

Theses and Dissertations

Small Unmanned Aerial Systems (sUAS) are an easily accessible technology that has become an increasingly large threat to US critical systems. This threatening technology demands using fault-tolerant, low-cost, replaceable, and accurate sensing resources, which counter the ubiquitous nature of sUAS [1]. Therefore, the methods developed in this thesis detect and track sUAS using easily accessible sensing resources, such as cellphones. First, we develop an acoustics sensor network-based sUAS detection methodology. In the latter effort, a deep learning model is trained using the acoustics data from the data collection to predict sUAS range from a cellphone. Combined, these two efforts demonstrate …

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Classification Tradeoffs In Multispectral Polarimetric Ladar Architectures, Connor B. Martin Mar 2023

Classification Tradeoffs In Multispectral Polarimetric Ladar Architectures, Connor B. Martin

Theses and Dissertations

An end-to-end LADAR system is modeled at the waveform level to perform material classification at a per-pixel basis. A K-Nearest Neighbors machine learning algorithm is chosen to make predictions using polarimetric material characteristics as features. A variable receiver design is modeled to allow for the use of multiple configurations of Polarization State Analyzers. This research investigates the inclusion of multiple wavelengths in the transmitted laser pulse to improve classification accuracy. Additionally, the effects of lowering the receiver’s detector bandwidth are investigated. Through the classification process, transmitting a multispectral laser pulse is shown to improve classification and may improve future LADAR …

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Atmospheric Polarization And Solar Position As Kalman Updates To A Navigation Solution, Thomas J. Wheeler Mar 2023

Atmospheric Polarization And Solar Position As Kalman Updates To A Navigation Solution, Thomas J. Wheeler

Theses and Dissertations

Simulation and physical testing of a sensor that measures relative position of the Sun and polarization of light in the atmosphere as a navigational aid in a Kalman filter.

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Entering Hyperspace: Conditional Hyperspectral Reflectance Image Generation Using Convolutional Neural Networks, Bret M. Wagner Mar 2023

Entering Hyperspace: Conditional Hyperspectral Reflectance Image Generation Using Convolutional Neural Networks, Bret M. Wagner

Theses and Dissertations

The field of remote sensing continues to expand in both commercial and defense domains. Development of advanced space based EOIR sensors has driven corresponding demand for sensor data for algorithm development. The AFIT Sensor and Scene Emulation Tool (ASSET) produces realistic synthetic electro-optical and infrared (EO/IR) data with absolute truth for the purpose of clutter suppression, target detection, and tracking algorithm development. This thesis presents a novel model which transforms panchromatic images into realistic hyperspectral reflectance images. The direct application of this model is to allows users to generate hyperspectral background images as inputs to ASSET allowing users to benefit …

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Environmental Trade-Offs Of Reverse Osmosis Water Purification Units (Rowpus) And Bottled Water, Caleb A. Boone Mar 2023

Environmental Trade-Offs Of Reverse Osmosis Water Purification Units (Rowpus) And Bottled Water, Caleb A. Boone

Theses and Dissertations

The Department of Defense (DoD) conducts many remote missions around the globe. As part of any remote basing strategy, potable water needs to be secured. Currently, there are three primary means of procuring potable water at remote locations: bottled water, on-site purification, or tie-in to existing, local infrastructure. The purpose of this study is to determine the environmental tradeoffs of bottled water and on-site treatment via a Reverse Osmosis Water Purification Unit (ROWPU), which uses multiple levels of filtration to make potable water from freshwater or saline water. A cradle-to- gate assessment was developed for both systems to create a …

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Method Development Biological Agent Personal Decontamination Effectiveness For Airman Battle Uniform Fabric Material: Ms2 Bacteriophage, Alisha Helm Mar 2023

Method Development Biological Agent Personal Decontamination Effectiveness For Airman Battle Uniform Fabric Material: Ms2 Bacteriophage, Alisha Helm

Theses and Dissertations

This article presents a study that investigates the effectiveness of a common decontamination (decon) strategy used by Airmen in the United States Air Force who may find themselves in a densely populated area during an emergency evacuation. Ultimately, this study addresses the following questions: Is there a significant difference in the number of viral particles being re-aerosolized before and after the applied decon strategy, and is this difference significant enough to consider the decon strategy effective? The study entails using MS2 bacteriophage to contaminate swatches of Airman Battle Uniform (ABU) fabric. Swatches were secured to a vortex centered in the …

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