Digital Commons Network^™

Low-Cost Transfers For Cislunar Liaison Navigation, Ka'eo J. Swartzmiller

Theses and Dissertations

CubeSats have an inherent limitation on volume due to their small form factor. Naturally, this extends to the capacity of on-board ΔV, thus limiting the maneuverability of the satellites. This limited maneuverability makes it extremely important to be intentional when planning out mission trajectories. The cislunar region subjects these trajectories to the gravitational forces of both the Earth and the Moon, making it all the more necessary to deliberately plan out maneuvers. The Circular Restricted Three Body Problem (CR3BP) provides a simpler model for estimating the motion of spacecraft within the cislunar region, allowing for the gravitational forces to be …

Spin State Of Positronium In Two Dimensions, Emille Bryant

Theses and Dissertations

We investigate the spin state of the electron-positron system positronium to determine experimental criteria that can identify a positronium anyon. Anyons have been posited to be the basis for a truly fault-tolerant quantum computer, but they have not been indisputably observed in experimental systems. Through the analysis of the fully relativistic symmetry group of fermions and bosons in three dimensions, we investigate the symmetry of its subgroups to determine that positronium in two dimensions behaves as a scalar with respect to rotations. We conclude that positronium in two dimensions has an arbitrary relative spin orientation of annihilation photons and only …

Designing An Experiment To Create And Evaluate Behavioral Changes In Air Force Pilots' Fuel Efficiency, Jackson Macias

Theses and Dissertations

Fuel represents over 70% of the logistical resupply demand within the Department of Defense, with the United States Air Force accounting for most of that consumption. While prior fuel efficiency efforts have primarily focused on technical upgrades, this research explores how behavioral interventions can influence pilot decision-making and operational energy outcomes. Using the Theory of Planned Behavior (TPB) as a guiding framework, this study investigates the effects of targeted behavioral strategies on pilots’ attitudes, subjective norms, perceived behavioral control, intentions, and actual fuel-efficient behaviors. A quasi-experimental design was applied through a controlled pilot study using simulator flights. Six participants were …

Designing The Protocol For An Experimental Flight Simulation Study Encouraging Fuel Efficient Behavior, Thomas S. Reardon

Theses and Dissertations

This study designed and tested an experimental instrument to examine how pilots respond to fuel efficiency feedback in a flight simulator. A standardized flight plan, script, and hardware setup were created using X-Plane 12 software and physical flight simulator hardware. The chosen sortie guided participants from Monterey Regional Airport to Moffett Federal Airfield using instrument flight rules (IFR). The flight script provided step-by-step guidance to ensure consistent behavior across participants. The simulator was mapped to match real cockpit controls and allowed for precise data collection including flight time, altitude, heading, and fuel use. The goal was to support a larger …

Implementing Lean Principles To Enhance Warehouse Operations At King Abdulaziz Air Base(Kaab): A Case Study Of Royal Saudi Air Force (Rsaf), Saleh A. Alghamdi

Theses and Dissertations

The Royal Saudi Air Force (RSAF) relies on efficient logistics to sustain readiness. At King Abdulaziz Air Base, warehouse receiving inefficiencies caused delays and waste. This study used Lean principles and a six-month time–motion analysis, with Pareto and Fishbone tools, to identify 55% waste in dead pile and 75% in palletized shipments. Standard times of 5.98 and 6.55 minutes were set. Key recommendations include SOPs, cross-training, forklift certification, layout redesign, and RFID. Lean adoption could save 100+ labor hours and $4,000 annually, improving safety, accuracy, and mission readiness.

Effect Of Workplace Design On Collaboration And Satisfaction In Space System Command, Joshua A. Hagood

Theses and Dissertations

This study addresses a significant knowledge gap regarding the influence of physical workplace design on employee collaboration and satisfaction with the physical environment within U.S. Space Force technical military organizations.  While seminal industry research consistently demonstrates that physical design and indoor environmental quality influence employee satisfaction and collaboration (e.g., Candido et al., 2015; Sailer et al., 2021), the understanding of these impacts within military contexts remains limited.  Using a quantitative post-occupancy evaluation survey, adapted from the Sustainable Post Occupancy Evaluation Survey (SPOES), multiple regression analyses revealed that physical elements collectively predict both satisfaction and collaboration.  The final simplified model showed …

Trends And Predictive Modeling Of Real Estate Prices In Major Saudi Arabia Cities, Meshal S. Aldahas

Theses and Dissertations

his research examines historical trends and explanatory modeling of real estate prices in major Saudi cities, with a focus on Riyadh, Jeddah, and Dammam. Using a mixed-methods approach, the study integrates quantitative data from 2010–2023, including housing and macroeconomic indicators, with qualitative insights drawn from over 320 survey responses that captured consumer sentiment on affordability, job security, and housing policies. A combination of descriptive statistics, ARIMA and Exponential Smoothing techniques was applied to detect long-term patterns, seasonal variations, and market shocks. Predictive modeling was conducted using Linear Regression, Decision Trees, and Neural Networks, with results showing that job security consistently …

A Review Of The United States' Long Term War Support Capabilities In The Indo-Pacific Command Region, Brian J. Mullin Jr.

Theses and Dissertations

This study examines U.S. maritime transportation readiness in the Indo-Pacific, highlighting fleet age, mariner shortages, shipyard decline, and port vulnerabilities. It also considers contested logistics and technological threats. Recommendations include fleet recapitalization, mariner pipeline growth, port diversification, and defensive upgrades. The study concludes that secure sea line assumptions are outdated and calls for greater resilience, with follow-on efficiency analysis proposed for ports and ships.

Investigating The Impact Of Forest Vegetation On Nuclear Weapon Prompt Radiation Energy Deposition, Paul A. Clement

Theses and Dissertations

This work seeks to answer the unstudied questions “Does a layer of vegetation impact the prompt radiation energy deposition in the soil from an atmospheric nuclear detonation?” and “If yes, by how much?” A new methodology was developed to repeatably automate and streamline a process of generating a three-dimensional geometry for subsequent radiation transport simulations and statistical analysis. The methodology streamlined three diverse applications: a three-dimensional mesh generator, a radiation transport simulation code, and a sensitivity analysis & uncertainty quantification software. The methodology was tested by simulating the quantitative influence that vegetation has on changing the energy deposition into the …

Automation Of Lcmc Logistics Processes: A Delphi Approach, Kline M. Alt

Theses and Dissertations

As the U.S. Air Force confronts growing complexity in system acquisition, the implementation of digital models in system design and logistics process management allows the incorporation of digital tools and the possibility for automation of portions of logistics processes. This thesis investigates where these technologies can be most effectively integrated within the Air Force Life Cycle Management Center logistics enterprise (AFLCMC). Using a three round Delphi study, AFLCMC logistics subject matter expert (SME) opinions were solicited from program-level senior logisticians, program managers to identify high-need areas, key success factors, and potential barriers to adoption. Quantitative consensus from Likert-scale and ordinal …

Modeling, Control, And Learning For Whole-Body Manipulation With Large-Scale Soft Robots, Curtis C. Johnson

Theses and Dissertations

This dissertation addresses the challenge of enabling soft robots to perform contact-rich manipulation tasks by overcoming limitations in hardware, modeling, control, and learning. First, we present hardware advancements with PneuDrive, a pneumatic control system for actuating soft robots. We also introduce Baloo, a hybrid soft-rigid robotic torso which achieves a single-arm payload capacity of 19.3 kg and robust whole-body grasping capabilities. We also develop a full-body tactile sensing system enabling piezoresistive sensor arrays to cover large areas (1 square meter) with over 8000 distributed sensing points. Second, we focus on developing tractable dynamic models based on the Recursive Newton-Euler algorithm …

An Antioxidant Approach To Ameliorate The Effects Of Radiation And Chemotherapy On Cognition, Raymond Anan Otoo

Theses and Dissertations

Acute Lymphoblastic Leukemia (ALL) is a hematologic malignancy that primarily affects children and young adults. While advancements in treatment—including chemotherapy and cranial irradiation—have significantly improved 5-year survival rates in children to nearly 90%, radiation-induced cognitive impairment (RICI) remains a persistent and debilitating side effect. The brain, particularly the hippocampus, is highly susceptible to radiation-induced oxidative stress and inflammation. In the treatment of ALL, the combined use of chemotherapy and radiotherapy contributes to a heightened oxidative burden, exacerbating the risk of cognitive dysfunction. Although previous studies have linked radiation exposure to neurocognitive decline, the molecular mechanisms underlying RICI and chemotherapy-induced cognitive …

Engineering Protein Linkers For Optimized Telsam-Darpin Fusion And Crystallization With Electric Field-Based Polymer Orientation, Maria Jose Pedroza Romo

Theses and Dissertations

Fusing a variant of the sterile alpha motif domain of the human translocation ETS leukemia protein (TELSAM) to a protein of interest significantly enhances crystallization and diffraction quality. TELSAM is a pH-dependent, polymer-forming crystallization chaperone that, when covalently fused to a protein, forms a well-ordered crystal lattice. However, the success of this method depends on two factors: 1) the design of the linker connecting TELSAM to the target protein, which influences both crystal packing and target orientation, and 2) the prevention of TELSAM polymer flipping, a phenomenon that disrupts lattice periodicity and impairs structure determination. To address the first challenge, …

Cost-Effectiveness Model For Reservoir Sediment Management Economics, Connor Ronald Hale

Theses and Dissertations

Reservoir sediment deposition poses a challenge to sustainable water supplies around the world. Sediment management has proven to be an expensive endeavor. Two models have been developed to guide economic analysis for reservoir sediment management, namely the Reservoir Sediment Economics Model (RSEM) and the Reservoir Conservation Model 2 (RESCON 2). While these are helpful tools for benefit-cost prefeasibility studies, they rely heavily on sometimes elusive estimations of the benefits of water supply. In this study, a new method for economic analysis is proposed that foregoes benefit-cost analysis in favor of a cost-effectiveness approach. The Sediment Management Cost-Effectiveness Model ranks sediment …

Satellite-Based Identification Of Mesoscale And Submesoscale Eddies And Fronts In The Gulf Of Mexico, Ethan Cruz

Theses and Dissertations

Mesoscale and submesoscale processes in the Gulf of Mexico (GoM) are fundamental in shaping the region’s physical and biogeochemical ocean dynamics. Advances in high-resolution satellite observations now allow detailed detection of submesoscale (< 25 km radius) and mesoscale eddies and ocean fronts, which drive heat, nutrient, and carbon fluxes. This dissertation integrates two complementary investigations: (1) a comparison of eddy-tracking algorithms: Contour Tracing (CT) and Temperature Thresholding (TT), applied to Optimum Interpolation Sea Surface Temperature (OISST, 1/4°) and Operational Sea Surface Temperature and Ice Analysis (OSTIA, 1/20°) products; and (2) a comparative evaluation of three ocean front detection algorithms: Canny Edge Detection (Canny), the Cayula–Cornillon Algorithm (CCA), and the Belkin–O’Reilly Algorithm (BOA), across multiple satellite-derived parameters, including sea surface temperature (SST), sea surface salinity (SSS), chlorophyll-a (Chl-a), and altimetry-derived absolute dynamic topography (ADT). The eddy-tracking analysis shows that the higher-resolution OSTIA consistently detected more eddies than OISST, with TT performing best during winter when SST gradients were strongest. The front detection analysis, incorporating datasets from the Surface Water and Ocean Topography (SWOT) and Plankton, Aerosol, Cloud, Ocean Ecosystem (PACE) missions, was evaluated under diverse conditions, including flood and drought periods, Loop Current phase changes, and extreme weather events. A machine learning–based Gaussian Mixture Modeling (GMM) approach was also developed, providing a novel framework for dynamic front detection. By benchmarking traditional and machine learning methods, this integrated study identifies optimal algorithm–dataset combinations for resolving submesoscale and mesoscale features in the GoM, with applicability to other regions.

Oxidation Resistance And Osmotic Energy Harvesting Applications Of Reduced Graphene Oxide Forward Osmosis Membranes, Michael Appiah-Kubi

Theses and Dissertations

Reduced graphene oxide (RGO) forward osmosis (FO) membranes have emerged as promising candidates for efficient wastewater management and osmotic energy harvesting, due to their enhanced chemical stability and superior FO performance for low-energy waste brine treatments, such as volume reduction of oxidative chromium brine for cost-effective disposal. This dissertation first examines the oxidation resistance of RGO forward osmosis membranes against chromate Cr (VI). Our findings reveal that both the water flux and the reverse salt flux of RGO membranes are suppressed, accompanying an enhanced reverse flux selectivity after exposure to an acidic medium of Cr (VI) (pH 2.0-7.0). Meanwhile, the …

Köppen-Geiger Climate Effects On F-15 Readiness Spares Package Parts, Maximus A. Fan

Theses and Dissertations

Readiness Spares Packages (RSP) are critical to deployed operations. Future demands of the Air Force require squadrons to operate in different climate environments from home stations. RSPs can sustain aircraft maintenance operations for up to 30 days. Currently, failure rates of parts within the RSP are assumed to be constant. This research aims to explore whether there is a difference in F-15 RSP failure rates when Koeppen climate classifications are taken into effect. The Koeppen-Geiger system classifies area climates based on the geography, elevation, and location. The history of operations and diversity of F-15 locations make the aircraft an ideal …

Acoustic Characterization And Modeling Of Heated Supersonic Tactical Jet Aircraft And Launched Rockets, Logan Troy Mathews

Theses and Dissertations

Understanding and accurately modeling the acoustic sources and propagation of high-intensity tactical jet aircraft and rocket noise is essential for vehicle design, environmental impact assessment, and mitigation strategies. Despite progress in the understanding of these sources, significant challenges persist in both predictive modeling and noise mitigation. This dissertation advances both the characterization of full-scale supersonic tactical jet aircraft noise sources and the development of modern empirical prediction models for rocket launch noise. Across multiple measurement campaigns and modeling efforts, the work integrates advanced array signal processing, high-fidelity field measurements, and improved empirical methods to expand the physical understanding of source …

Evaluating Adjustment And Proficiency Disparities In Virtual Reality, Mohammad Jahed Murad Sunny

Theses and Dissertations

The rapid integration of VR in various application domains necessitates a deeper understanding of how levels of user experience impact user performance and task efficiency. This study investigates the relationship between experience with VR, expertise in 3d computer gaming, and physiological skills across multiple performance metrics, such as task-completion time, task load, accuracy, manipulation speed, and related spatial requirements. In a comprehensive analysis of multiple levels of VR experience and 3d computer-game expertise, we identified key trends that indicate increased experience in both domains significantly enhances task efficiency while at the same time reduces perceived workload and improves task accuracy. …

Exposure To Zinc Oxide Nanoparticles Reveals A Death Resistance Mechanism In Dictyostelium Discoideum, Zoya Nadeem Faruqui

Theses and Dissertations

Zinc oxide nanoparticles (ZnO NPs) are very versatile due to their multifunctional properties including unique physicochemical and antimicrobial characteristics. They are widely utilized across various fields such as biomedical, industrial fields, environmental remediation, and agriculture. Therefore, their cytotoxic effects on biological systems necessitate a deeper understanding of the cellular responses to nanoparticle exposure. This project primarily investigates the impact of ZnO NPs on the model organism Dictyostelium discoideum AX4 (social amoeba) which has not been examined before unlike a vast variety of organisms in the literature. The cytotoxic effects of ZnO NPs on Dictyostelium discoideum AX4 cells are compared with …

Re-Engaging Driver Attention Using Chatgpt: A Multimodal Study On Stress Impact And Driving Performance, Alaa Zaki Elfiqi

Theses and Dissertations

Driving is considered a complex task that requires continuous focus and attention from the driver. Driving performance can also be impacted by changes in the driver’s stress level. However, limited research explores methods to address this challenge. With the current advances in Large Language Models (LLMs) and their ability to engage in human-like interaction, this study investigates the potential of using ChatGPT, designed to speak Egyptian Arabic, in re-engaging driver attention under different driving scenarios for low-stress and high-stress conditions within a virtual reality (VR) environment driving simulator. Drivers were asked to follow a leading car into two scenarios with …

Mitigating Ultrasonic Attack On Drones Using Meta-Material Acoustic Resonators, Corey Thomas Churgin

Theses and Dissertations

The purpose of this research was to reproduce ultrasonic attacks on consumer drone gyroscopes and mitigate the attacks using specifically designed meta-material acoustic resonators. Drones use a Micro Electrical Mechanical Systems (MEMS) Gyroscope for collecting flight data, due to the mechanical nature of these gyroscopes they are susceptible to being resonated at specific frequencies. For these MEMS gyroscopes the majority have a resonance frequency in the ultrasonic range, making attack imperceptible by humans. (1) A Laser Doppler Vibrometer was used to accurately measure the frequency which affects the drone’s gyroscope. (2) To mitigate the effects of the attacks acoustic resonators …

Transition And Instability Characteristics Of The Separated Shear Layer Formed At Low Reynolds Number Over Three-Dimensional Irregular Rough Surface, Ganesh Kt Mr

Theses and Dissertations

The present experimental work investigates the effects of irregularly roughened surfaces and imposed streamwise pressure gradients on the topological, transitional, and instability characteristics of the laminar separated shear layer (SSL). Experiments are conducted in the low-speed wind tunnel for 𝑅𝑒𝑡=30000, based on the thickness of the airfoil model, t, and freestream turbulence intensity, fst = 0.8%. The airfoil model used in this study features a semicircular leading edge followed by a constant-thickness flat portion and a pitchable trailing-edge flap. Test conditions include two rough surfaces: sandblasted (SB) and sand-deposited (SD), and flap deflections: 𝛽=−30° and 𝛽=+30°, imposing adverse (APG) and …

A Contemporary Approach For Exploring The Influence Of Detoxification And Standardization Of Traditional Metallopharmaceutical Product Pharmacological And Toxicological Aspects, Malarvizhi K

Theses and Dissertations

Polyherbomineral formulation possess unique medicinal properties due to the presence of metals and minerals as integral part, as processed in addition to specific herbals. There is an increased interest in metallopharmaceuticals in clinical and research areas, because of their immense therapeutic efficiency towards multiple diseases and evidence for non-toxic claim. Sivanar Amirtham is one of the polyherbomineral Siddha medicine recommended for the treatment of various respiratory diseases and other ailments including antidote therapy for poisonous bites. The present research work attempted for standardization of Sivanar Amirtham preparation as per the traditional standard protocols (including the detoxification process of raw materials) …

Magnetic Molecularly Imprinted Polymers For Quercetin Adsorption: Fabrication, Characterization, And Application, Vinitha Ug

Theses and Dissertations

A highly selective Magnetic Molecularly Imprinted Polymer (MMIP) was developed for the detection and purification of Quercetin. The Density Functional Theory was utilized for the selection of suitable monomers based on binding energy interaction between quercetin and monomers (Acrylamide, Acrylonitrile, Methacrylic Acid). From computational studies, Acrylamide was selected as a suitable monomer for the synthesis of MMIP. Under ultrasound irradiation both quercetin and naringin imprinted materials MMIP-Q and MMIP-N were fabricated.

Compared to ultrasound-assisted synthesis, Microwave Synthesis provides uniform heat transfer throughout the reaction solution, which enables uniformity in the size of synthesised material, increases the yield of material and …

Design And Development Of Deep Learning Based Generic Platform For Promoting Precision Agriculture, Srilakshmi A

Theses and Dissertations

Precision agriculture also referred as precision farming or smart farming, is an innovative approach to agricultural management that leverages technology and data to optimize various aspects of the farming process. This approach aims to make farming more effective, sustainable, and profitable by affording farmers with the application tools and information they need to make more informed decisions.

Precision agriculture combines elements of agriculture, technology, and data science to enhance crop production, and resource utilization. Precision agriculture techniques can be highly effective in leaf disease detection within crop fields. Machine learning has been developed incredibly across multiple domains and shown it …

Factors Influencing The Performance Of Farmer-Producer Organizations (Fpos) And Their Societal Impact In Tamil Nadu, Arjune S

Theses and Dissertations

Farmer Producer Organizations (FPOs) are formed mainly for the farmers to have better institutional access to acquire them. They are also under the inspiration of the director's abstinence and the incentive of getting more money. These are socio-psychological individual differences and thus of importance to markets, the perception of markets, and market relevance of group interaction. Self-esteem, attitude to participation in group activities, and willingness to participate in these types of activities are of some significance for his/her performance because they have an effect on their performance afterward.

Farmer social empowerment increased but not farmer economic empowerment did so much …

Facile Fabrication Of Protein-Polysaccharide Conjugate Multifilament Nerve Guidance Conduit For Peripheral Nerve Regeneration, Preethy Amruthavarshini R

Theses and Dissertations

Long segmental defects in peripheral nerves impair sensory and motor function by disrupting neural impulse transmission. End-to-end autologous grafting with proper fascicular complementation has demonstrated functional recovery per the Medical Research Council Classification (MRCC). However, obtaining donor nerve tissue exceeding 30 mm remains a significant challenge. Artificial hollow conduits serve as an alternative but are limited to defects smaller than 30 mm due to inadequate innervation across the lumen.

Multichannel nerve guidance conduits (mNGCs) have emerged as a promising solution by enhancing fascicular complementation similar to autografts. This study presents a two-step approach for fabricating nerve conduits with precise fascicular …

3d Bioprinting On Electrospun Nanofibrous Scaffolds To Fabricate Myocardial Patches, Muthu Parkkavi S

Theses and Dissertations

Tissue-engineered three-dimensional (3D) myocardial patches offer superior and innovative treatment strategy for myocardial infarction (MI). Among the various scaffold fabrication techniques, electrospinning and 3D bioprinting have received great attention due to their ability to recreate native cardiac tissue mimetic characteristics. Despite several advantages, electrospun nanofibers have limitations in cell delivery due to random cell seeding, while bioprinting faces challenges in creating hydrogel constructs with ideal mechanical properties capable of supporting cardiac contraction/relaxation cycle. Hence in this work, hybrid myocardial patches were developed by converging electrospinning and bioprinting techniques.

Electrospinning of PLCL:PEOz (B73, 7:3 blend of poly-L-lactide-co-ε-caprolactone (PLCL) and polyethyl oxazoline …

Detailed Modelling And Analysis Of A Shake Table Comprising Hybrid Actuation And Load-Balancing Mechanism, Xavier Reni Prasad

Theses and Dissertations

Catastrophic earthquakes endanger human lives by severely damaging critical infrastructure such as nuclear plants, bio-laboratories, and bridges. Developing earthquake-resistant structures is vital to mitigate these risks. Shake tables replicate recorded earthquake ground motions to assess structural performance. This research presents a novel three-legged, six degrees of freedom (6-DOF) hybrid shake table with a cost-effective design and decoupled motion control, offering a viable alternative to conventional six-legged models.

This architecture effectively decouples actuator motions by employing hydraulic actuators for 3-DOF spatial movement and electromechanical actuators for 3-DOF planar motion. Servo-hydraulic actuators support the static payload against gravity, while lightweight electromechanical actuators …