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Graduate Theses and Dissertations

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Effect Of Marination And Storage Time On The Properties And Meat Quality Of Broiler Breast, Mayra Mabel Herrera Rivera Aug 2025

Effect Of Marination And Storage Time On The Properties And Meat Quality Of Broiler Breast, Mayra Mabel Herrera Rivera

Graduate Theses and Dissertations

Abstract The poultry industry has implemented numerous methods, as marination and aging, to improve meat quality and satisfy consumer demands. Three experiments were developed to assess the effects of vacuum tumble marination and aging on the proteins of chicken breast. These experiments utilized 0.75 % sodium chloride, 0.45 % phosphate, and water in a marinade. In experiment one, 270 fillets were allocated into six treatment groups, each comprising 45 fillets. Six days of storage time were used, marinating and storing the fillets in each group at a temperature of 4°C. Following each day of storage period, the fillets underwent a …


Design And Validation Of A High-Frequency Multi-Output Dc-Dc Converter For Radar Power Applications, Tory Sutton Aug 2025

Design And Validation Of A High-Frequency Multi-Output Dc-Dc Converter For Radar Power Applications, Tory Sutton

Graduate Theses and Dissertations

Modern radar systems and advanced electronics demand compact, efficient, and reliable power solutions capable of delivering multiple tightly regulated voltage rails under strict size, weight, power, and reliability (SWaP-R) constraints. This thesis presents the design, implementation, and validation of a high-frequency (460 kHz – 1 MHz), multi-output DC-DC converter for a mission?critical radar platform, addressing both integration and performance requirements. The first implementation, an isolated modular converter (IMC), utilizes isolated silicon?based DC-DC modules to deliver twelve isolated voltage outputs from a single input. This approach provided robust electrical isolation, simplified system integration, and minimized design risk, making it well-suited for …


A Pastoral River: Reimagining The Narrative Of Buffalo National River, Thomas Andrew Medford Aug 2025

A Pastoral River: Reimagining The Narrative Of Buffalo National River, Thomas Andrew Medford

Graduate Theses and Dissertations

This thesis examines the creation of Buffalo National River (BNR) from the perspective of dispossessed landowners. A unit of the National Park Service in the Arkansas Ozarks, BNR has garnered little scholarly attention in this light, despite present-day resentment of the federal government by locals. The park was signed into law in 1972, capping a years-long debate about the fate of the river. Some had supported a tenacious U.S. Army Corps of Engineers effort to dam the river, others backed a well-organized, preservationist-led campaign to create a park, while on-the-river landowners typically preferred the status quo of private ownership. Many …


Improved Autofluorescence Lifetime Decay Analysis For Identification Of Cellular Autofluorescence Biomarkers For Label-Free, Single-Cell Assessment Of Mitochondrial Membrane Potential, Olivia Isabel Kolenc Aug 2025

Improved Autofluorescence Lifetime Decay Analysis For Identification Of Cellular Autofluorescence Biomarkers For Label-Free, Single-Cell Assessment Of Mitochondrial Membrane Potential, Olivia Isabel Kolenc

Graduate Theses and Dissertations

Optical imaging of metabolism using the autofluorescence of the metabolic cofactors NADH, NADPH, and FAD has a wide range of sensitivities and the capability to collect a great deal of metabolic information. Multiphoton microscopy (MPM) is a non-invasive, label-free optical imaging technique capable of performing fluorescence lifetime imaging (FLIM) using time correlated single photon counting (TCSPC). However, autofluorescence FLIM presents a challenge in collecting sufficient photons to provide adequate signal to noise ratios (SNR) for analysis. Additionally, the specificity of autofluorescence biomarkers of metabolism has not been well-defined. Contextualizing these autofluorescence measures using established functional biomarkers can improve interpretability of …


Growth And Characterization Of Thin Film Gase On Si(111) And Sio2/Si(001) Substrates By Molecular Beam Epitaxy, Christopher John Hocevar Aug 2025

Growth And Characterization Of Thin Film Gase On Si(111) And Sio2/Si(001) Substrates By Molecular Beam Epitaxy, Christopher John Hocevar

Graduate Theses and Dissertations

Gallium selenide (GaSe) is a thin-film semiconducting material with promising optoelectronic properties, including a tunable bandgap, high photosensitivity, and atomic-layer scalability. These characteristics make it suitable for devices such as photodiodes, FETs, MOSFETs, Hall effect sensors, and p–n diodes. In this study, GaSe thin films were grown on SiO2 and Si(111)-7×7 substrates using molecular beam epitaxy (MBE) to compare growth behavior across different substrates. The films were characterized using Raman spectroscopy, X-ray diffraction (XRD), atomic force microscopy (AFM), photoluminescence (PL) spectroscopy, and reflection high-energy electron diffraction (RHEED). RHEED confirmed the 7×7 reconstruction of the Si(111) surface and the amorphous nature …


Synthesis, Structural Characterization And Optical Studies Of Silver-Indium-(Zinc)-Chalcogenide Fluorescent Quantum Dots, Sujal Acharya Aug 2025

Synthesis, Structural Characterization And Optical Studies Of Silver-Indium-(Zinc)-Chalcogenide Fluorescent Quantum Dots, Sujal Acharya

Graduate Theses and Dissertations

Developing a non-toxic, high-performance fluorescent nanomaterial is crucial for overcoming the environmental and health restrictions of current cadmium, and lead based quantum dots (QDs), which limit the application of quantum dots in optoelectronics and bioimaging. In this thesis, we synthesized environmentally friendly AgInS2 QDs by a colloidal method, systematically altering the In/Ag precursor ratio from 2 to 6 to study the impact on their optical and photophysical properties. Our goals were to find the optimal stoichiometry for maximum quantum efficiency and stability. We also investigated further improving optical and photophysical properties through shelling with ZnS. The emission spectra appeared broad, …


Controlling Electroless Deposition On Polymer Interfaces Towards Discrete Functional Particle Synthesis, Grecia Pierina Alvarado Munoz Aug 2025

Controlling Electroless Deposition On Polymer Interfaces Towards Discrete Functional Particle Synthesis, Grecia Pierina Alvarado Munoz

Graduate Theses and Dissertations

Electroless deposition is a process that facilitates the formation of metal layers on surfaces through the reduction of metal ions onto a surface in the presence of a sacrificial reducing agent. This process can be applied to synthesize conductive metal layers on insulators such as glass or polymers. The kinetics of heterogeneous deposition depend on the interfacial surface chemistry, including the presence of added catalyst materials, as well as the bulk chemical environment, such as the concentration of metal ions and sacrificial reductants. Furthermore, the homogeneous formation of metal nanoparticles may compete with the deposition reaction, adversely affecting the control …


Structure, Thermodynamics, And Dynamics Of Acetonitrile In Titan-Like Conditions, Sagar Chandra Roy Aug 2025

Structure, Thermodynamics, And Dynamics Of Acetonitrile In Titan-Like Conditions, Sagar Chandra Roy

Graduate Theses and Dissertations

Titan is one of the most interesting satellites in the solar system. It is the only other place in the solar system containing stable deposits of liquid and a hydrological cycle other than earth. The abundant existence of N2 and CH4 in Titan’s atmosphere makes nitrile formation highly likely both in the atmosphere and surface. Infrared spectrometer data from Voyager 1 expedition revealed the presence of acetonitrile (CH3CN) in the atmosphere along with several other nitriles such as hydrogen cyanide (HCN) and cyanoacetylene (HC3N). According to theoretical models nitrile formation is caused by photodisscociation of nitrogen in the tholin haze …


Polymer-Enhanced Nanopore Sensing, Eugene Gyasi Agyemang Aug 2025

Polymer-Enhanced Nanopore Sensing, Eugene Gyasi Agyemang

Graduate Theses and Dissertations

The resistive pulse technique characterizes single analytes by detecting fluctuations in the ion current as they pass through a narrow orifice connecting two electrolyte-filled chambers, each containing a single electrode. The amplitude, shape, frequency, and duration of these fluctuations primarily provide information about the analyte’s size, shape, concentration, and net surface charge, respectively. One configuration for resistive pulse measurements is of an electrolyte-filled nanopipette immersed in a bath, where the nanopipette tip acts as the nanoscale orifice. It was previously shown that incorporating the large quantities polymer polyethylene glycol (PEG 8K, 50% w/v) into the external electrolyte bath dramatically enhanced …


Contrastive Loss In Recommendation Systems, Maryam Aghamohammadghasem Aug 2025

Contrastive Loss In Recommendation Systems, Maryam Aghamohammadghasem

Graduate Theses and Dissertations

A recommendation system is a bridge between users and products, which is widely used in e-commerce such as Amazon and Netflix. This study investigates the use of Graph Neural Networks (GNNs), Light Graph Convolution Network(LightGCN) and Graph Sample and Aggregate (GraphSAGE), in the recommendation system on two categories of Amazon review datasets ( "All Beauty" and "Tools and Home Improvement"). The novelty of this work includes combining supervised and self-supervised learning through Weighted Approximate Rank Pairwise (WARP) and Information Noise-Contrastive Estimation (InfoNCE) losses, to optimize the embeddings of users and recommended items in the shape of a ranking list. The …


Synthesis And Characterization Of Polymer-Coated Metal Nanostructures And Gelatin-Incorporated Hydrogels For Biomedical Use, Deborah Takyibea Okyere Aug 2025

Synthesis And Characterization Of Polymer-Coated Metal Nanostructures And Gelatin-Incorporated Hydrogels For Biomedical Use, Deborah Takyibea Okyere

Graduate Theses and Dissertations

The development of advanced materials for disease management and treatment presents a pressing challenge in the health sector. The overall objective of this research is to contribute to the development of advanced materials with tailored properties for biomedical applications, with a focus on cost-effective and robust nanoparticles and biomaterials. The first part of this work focuses on designing and synthesizing earth-abundant copper nanoparticles with desired optical properties. Copper nanoparticles, which provide a more affordable alternative to gold and silver, are being investigated due to their unique plasmonic properties. However, their susceptibility to oxidation limits their application. To address this challenge, …


From Stem Cells To Smooth Muscle Cells: Characterizing Secretome Profiles And Evaluating Regenerative Potentials, Christofer Baldwin Aug 2025

From Stem Cells To Smooth Muscle Cells: Characterizing Secretome Profiles And Evaluating Regenerative Potentials, Christofer Baldwin

Graduate Theses and Dissertations

This dissertation examines the role of vascular smooth muscle cells (VSMCs) in vascular disease and the potential of stem cell-derived VSMCs (SC-SMCs) for regenerative medicine. VSMCs are crucial for maintaining function; however, their dysregulation contributes to the progression of diseases like atherosclerosis, vascular calcification, and aneurysms. Disease progression is influenced by various environmental factors, prompting VSMCs to switch phenotypes, leading to adverse vascular remodeling. This research focuses on adult bone marrow mesenchymal stem cells (BM-MSCs) and adipose-derived stem cells (ADSCs) as sources for generating reparative VSMCs. Through comparative analysis, it investigates the effects of SC-SMCs on VSMC biomarker expression and …


A Multicomponent Microneedle Patch For The Delivery Of Meloxicam For Veterinary Applications, Katherine Alejandra Miranda Munoz Aug 2025

A Multicomponent Microneedle Patch For The Delivery Of Meloxicam For Veterinary Applications, Katherine Alejandra Miranda Munoz

Graduate Theses and Dissertations

Veterinary medicine requires innovative drug delivery strategies to enhance therapeutic efficacy while minimizing stress and handling. This dissertation explores the development and application of biodegradable microneedle patches for the transdermal delivery of meloxicam in livestock, offering a minimally invasive alternative to traditional administration methods. The research investigates the fabrication and characterization of microneedles using polyvinyl alcohol, collagen, and chitosan blends, demonstrating their mechanical strength, biocompatibility, and ability to facilitate sustained drug release. In vitro and in vivo evaluations confirm effective skin penetration, dissolution, and localized drug delivery. Pharmacokinetic studies highlight anatomical site-dependent variations in drug absorption, emphasizing the need for …


Impact Of Three Professional Development Models (Online, Face-To-Face, And Hybrid) On Bhutanese Inservice Science Teachers' Conceptions Of Aspects Of Nature Of Science (Nos) With Reports Of Translation Of Nos Content Into Classroom Teaching Practices, Pabi Maya Das Aug 2025

Impact Of Three Professional Development Models (Online, Face-To-Face, And Hybrid) On Bhutanese Inservice Science Teachers' Conceptions Of Aspects Of Nature Of Science (Nos) With Reports Of Translation Of Nos Content Into Classroom Teaching Practices, Pabi Maya Das

Graduate Theses and Dissertations

Having a scientifically literate citizenry is an asset nationally and globally, and knowledge of the nature of science (NOS) is a crucial element in such literacy. Science teachers are a vital link if students are to understand key elements of the NOS, yet teachers themselves often lack knowledge of NOS and how to integrate NOS content into science lessons. Investigating the impact of a series of inservice professional development experiences using three distinct delivery modes (face-to-face, hybrid, online) for teachers in my home country of Bhutan is the overarching goal of the study reported here. The study used a mixed-methods …


Classifying Advanced Persistent Threat Stages And Techniques Via Graph-Enhanced Network Flow Representations, Md Taef Uddin Nadim Aug 2025

Classifying Advanced Persistent Threat Stages And Techniques Via Graph-Enhanced Network Flow Representations, Md Taef Uddin Nadim

Graduate Theses and Dissertations

Advanced Persistent Threats (APTs) are complex, stealthy attacks that involve multiple stages and many attack techniques used in each stage, making them difficult to defend against. Although many solutions can detect APTs, most of them only detect the existence of attack, but cannot produce fine-grained classification over the stage of the APT and the specific attack technique used. Some existing solutions can classify the stages of APT, but few of them provide attack technique classification, and existing work do not provide interpretability for the classification or countermeasures for the attack. In this thesis work, we propose a solution named CAPTure, …


Small Angle X-Ray Scattering Studies Of Collagenase H Mutant, Colh-E416q, Madelyn Millsap Aug 2025

Small Angle X-Ray Scattering Studies Of Collagenase H Mutant, Colh-E416q, Madelyn Millsap

Graduate Theses and Dissertations

Collagenase H (ColH) from Hathewaya histolytica plays a central role in collagen degradation through endopeptidase and carboxytripeptidase reactions. To better understand how its domain architecture supports these functions, we examined the solution structure of a catalytically inactive mutant, ColH-E416Q, using small-angle X-ray scattering (SAXS). The E416Q mutant is catalytically inactive because the glutamate residue at position 416, which normally functions as a general acid/base during catalysis, is replaced by glutamine—an amide that cannot donate or accept protons effectively, thus disabling the proton transfer steps essential for peptide bond hydrolysis. SAXS results indicate that the E416Q substitution leaves overall domain architecture …


Advancing Point-Of-Care Diagnosis Of Joint Infection Using A Diffuse Reflectance Spectroscopy (Drs) System, Erin Elizabeth Drewke Aug 2025

Advancing Point-Of-Care Diagnosis Of Joint Infection Using A Diffuse Reflectance Spectroscopy (Drs) System, Erin Elizabeth Drewke

Graduate Theses and Dissertations

Septic arthritis is a severe joint infection that can rapidly destroy cartilage and cause lifelong disability if not diagnosed and treated promptly. Faster, bedside diagnostic tools are needed to reduce delays and support timely treatment decisions while preserving standard laboratory workflows. A syringe-mounted diffuse reflectance spectroscopy (DRS) system was developed for rapid, sterile, point-of-care measurement of synovial fluid optical properties. Broadband light (400–650 nm) was delivered and collected through the syringe barrel without contaminating the sample. An empirical lookup table (LUT) and a boundary-aware Monte Carlo (MC) model were implemented to extract absorption (μₐ) and reduced scattering (μs′) coefficients from …


Effect Of Dietary Tryptophan Supplementation And Heat Stress On Pasture Broiler Welfare And Performance, Jaelen Matthew Cherry Aug 2025

Effect Of Dietary Tryptophan Supplementation And Heat Stress On Pasture Broiler Welfare And Performance, Jaelen Matthew Cherry

Graduate Theses and Dissertations

Pasture-raised broiler chickens face temperature extremes that can threaten welfare. In the study, we evaluated whether a 0.26 % tryptophan-supplemented diet (T) improved heat stress (HS) resilience in Ross-708 broilers raised on pasture. At D14, birds began the T or remained on the control diet (C) and were moved outdoors. On D20 and 41, half of each group underwent six-hour HS; the remainder stayed under thermoneutral (TN) conditions. Weekly body weight, feed intake on D20 and D41 were recorded, and fear was measured using the Tonic Immobility (TI) test. Neither diet nor HS affected body weight. However, tryptophan supplementation resulted …


Multivariate Optical Imaging Of The Oxygen-Metabolism Axis, Jesse D. Ivers Aug 2025

Multivariate Optical Imaging Of The Oxygen-Metabolism Axis, Jesse D. Ivers

Graduate Theses and Dissertations

Metabolic reprogramming is a characteristic hallmark of multiple pathologies and promotes disease progression, survival, and severity. Current methods to investigate metabolic reprogramming, however, require reductions of dimensionality both because of instrumentation limitations and analysis tools. This work aims to define a blueprint for high dimensional study of the oxygen metabolism axis to enable more sensitive study metabolic reprogramming. We hypothesized (1) multivariate imaging of metabolic and oxygenation metrics in ex vivo tissue sections would elucidate differences in resistant and sensitive head and neck squamous cell carcinoma (HNSCC) xenografts that traditional uni-variate methods miss and (2) an engineered hyperspectral darkfield microscopy …


Strain Induced Quantum Emitters In Monolayer Wse₂: Fabrication And Characterization Of Dimple Dot Devices, Garrett Maxwell Kitterman Aug 2025

Strain Induced Quantum Emitters In Monolayer Wse₂: Fabrication And Characterization Of Dimple Dot Devices, Garrett Maxwell Kitterman

Graduate Theses and Dissertations

Strain induced defects in monolayer tungsten diselenide (WSe₂) give rise to localized exciton funnels, offering a promising approach for the development of tunable quantum emitters. The quantum devices fabricated for this thesis used a modified dimple dot geometry, in which nano indentation creates a strain profile on the monolayer WSe₂. This allows for the funneling of excitons to a confined region. These strain induced funnels enable localized emission from single excitons in WSe₂. Device fabrication was carried out through mechanical exfoliation, dry transfer, and electron beam lithography of Cr/Au gates on a SiO₂ substrate. These devices were then characterized using …


Modeling U.S. Corn Production Archetypes In The Agricultural Policy/Environmental Extender Model To Generate Life Cycle Assessment Inventory Data, Brandon Taylor Aug 2025

Modeling U.S. Corn Production Archetypes In The Agricultural Policy/Environmental Extender Model To Generate Life Cycle Assessment Inventory Data, Brandon Taylor

Graduate Theses and Dissertations

Corn (Zea mays) is an important crop grown across the US for many uses such as grain for animal feed, bio-ethanol production, food products, and industrial products. Corn is produced in almost every state in the US, but most corn production is concentrated in the Corn Belt Region including Iowa, Illinois, Ohio, Indiana, Minnesota, and Nebraska. Although technologies and production practices are improving corn production efficiency primarily through increased yields (improved land use), corn production at this scale greatly impacts the environment through emissions from fertilizer and pesticide runoff and leaching, soil degradation due to improper field practices, as well …


Assessing The Recall Of Traffic Safety Campaigns In Arkansas, Pratik Babu Pokharel May 2025

Assessing The Recall Of Traffic Safety Campaigns In Arkansas, Pratik Babu Pokharel

Graduate Theses and Dissertations

This study estimates the degree to which drivers recall traffic safety campaigns based on sociodemographic characteristics including driving frequency, vehicle type, education, income, age, household composition, race, and gender. Traffic safety campaigns are efforts to educate, persuade, and inspire individuals to adjust their attitudes and behaviors for improved road safety, utilizing planned communications over a set time period. They aim to encourage safe driving using slogans shown on television, radio, social media, billboards, and variable message signs. Two years of a mail-based survey conducted in Arkansas were used to estimate binary logistic regression models for each of four safety campaigns. …


Impact Of Various Sealant Materials On Low Temperature Properties Of Asphalt Mixtures, Jackson Hedden May 2025

Impact Of Various Sealant Materials On Low Temperature Properties Of Asphalt Mixtures, Jackson Hedden

Graduate Theses and Dissertations

In the United States, 43% of the pavement network is in poor condition which can be attributed primarily to different modes of cracking. This network is constantly exposed to the elements and loading leading to thermal and fatigue cracking respectively. Cracking can be addressed through two primary means: mix design and preservation through the application of treatments. However, evaluating these two avenues requires a test that can easily and effectively measure the influence of these factors on thermal and fatigue cracking performance. The two main objectives of this study were to explore the influence of non-standard treatment material (sealant material) …


Quantifying The Role Of Climate On Tropical River Flow (Guarare River) Along The Panama Pacific Coast, 1981 – 2020., Jessie Abrego - Bonilla May 2025

Quantifying The Role Of Climate On Tropical River Flow (Guarare River) Along The Panama Pacific Coast, 1981 – 2020., Jessie Abrego - Bonilla

Graduate Theses and Dissertations

The Guarare River watershed on the Azuero Peninsula of Panama, part of the Panamanian Dry Arc, experiences significant hydrological variability driven by seasonal changes, elevation, and the El Niño/Southern Oscillation (ENSO). This study investigates precipitation and river discharge patterns over 40 years (1981 – 2020), showing that elevation influences rainfall distribution, with higher-altitude areas receiving more precipitation during the Neutral and El Niño phases. In contrast, La Niña phases bring increased rainfall to lower-elevation areas, such as Pocrí. Seasonal ENSO effects reveal that El Niño phases reduce dry-season precipitation, lowering river discharge. La Niña events sustain high wet-season rainfall, peaking …


Effect Of Beam Bracing On The Seismic Performance Of Laterally Skewed Reduced Beam Section Moment Connections With Composite Concrete Slabs, Pratik Ghimire May 2025

Effect Of Beam Bracing On The Seismic Performance Of Laterally Skewed Reduced Beam Section Moment Connections With Composite Concrete Slabs, Pratik Ghimire

Graduate Theses and Dissertations

Existing experimental reduced beam section (RBS) moment frame investigations, particularly those used for prequalification in AISC-358, consider orthogonally oriented beam-to-column connections. While the design commentary provided in AISC-358 references recent skewed SMF numerical studies and potential performance effects when a lateral beam skew is introduced, limited experimental studies have been performed to verify the numerical findings. This study presents an experimental investigation into the cyclic behavior of RBS special moment frames that have lateral skew at the beam-to-column connection and composite concrete slabs. In this study, a skewed composite double-sided RBS connection is tested, having beam bracing outside the RBS …


Novel Atomic Layer Deposition Processes Of Silver For Battery Applications, Darlington Ehijie Imhanzuaria May 2025

Novel Atomic Layer Deposition Processes Of Silver For Battery Applications, Darlington Ehijie Imhanzuaria

Graduate Theses and Dissertations

This thesis presents a novel approach to enhance the performance and stability of anode-free lithium-ion batteries (AFLBs) by employing atomic layer deposition (ALD) to coat copper (Cu) current collectors with a silver-aluminum oxide (AgAlOx) layer. Leveraging the unique capabilities of ALD for precise and conformal deposition, the AgAlOx coating was achieved using triethyl phosphine-(6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedionato)-silver(I) (Ag(fod)(PEt3)), trimethylaluminum (TMA), and de-ionized water (H2O) as precursors. This innovative coating method significantly enhanced the cycling stability and Coulombic efficiency (CE) of both Li||Cu and Cu||NMC811 cells, as evidenced by improved electrochemical performance metrics. The AgAlOx layer …


Sample Archival System For Quantum Device Manufacturing: Design, Construction, And Integration, Corbin Russ May 2025

Sample Archival System For Quantum Device Manufacturing: Design, Construction, And Integration, Corbin Russ

Graduate Theses and Dissertations

In the manufacturing of quantum devices using 2-dimentional (2D) materials, current processes rely on manual operations of production. MonArk Quantum Foundry is developing a facility to semi-automatically, and ultimately automatically, produce 2D materials. One crucial step in the experimentation process is archiving these materials and completed chips for future access. The sample archival system robot was produced to fulfill this need. The system is a 4 Degree-of-freedom (DOF) cartesian storage system that stores custom aluminum chip trays of sixty samples, having a total storage capacity of 14,400 samples. The sample archive system meets key goals from: it integrates with the …


Thermal Design And Control Of A Pcb-Based Solid-State Gas Generator (Ssgg) Heater For Space Applications, Chandler Dye May 2025

Thermal Design And Control Of A Pcb-Based Solid-State Gas Generator (Ssgg) Heater For Space Applications, Chandler Dye

Graduate Theses and Dissertations

This thesis presents the development and experimental validation of a compact, solid-state gas generator (SSGG) heater integrated into a printed circuit board (PCB) for use in satellite deorbiting systems. Designed for CubeSat-class spacecraft, the system produces gas via the thermal decomposition of sodium azide (NaN₃). The project emphasizes minimal mass, low power consumption, and mechanical simplicity – key constraints for modern space missions. The heater system relies on Joule heating through patterned copper coils embedded within the PCB structure. NaN₃ is deposited into wells drilled into the board surface, where localized heating initiates its decomposition near 300°C. A range of …


Using Scaffolding, Gamification, And Self Awareness To Create Responsive Ux/Ui In Cad Software To Nurture Metacognition In Novice Users, Obed Ibrahim Gonzalez May 2025

Using Scaffolding, Gamification, And Self Awareness To Create Responsive Ux/Ui In Cad Software To Nurture Metacognition In Novice Users, Obed Ibrahim Gonzalez

Graduate Theses and Dissertations

Computer-aided Design (CAD) software represents a significant shift from manual and analog design processes to digital workflows, offering substantial utility, accuracy, and productivity benefits. However, CAD software often presents a steep learning curve, particularly for novice users who are new to the software or possess only basic knowledge. Traditional CAD curricula have predominantly focused on technical problem-solving—teaching tools and systems—while often neglecting strategic knowledge that encompasses reflection, planning, and refining, which are essential components of metacognition. Metacognition is crucial for transforming novices into experts who use fewer and more complex commands, employ sophisticated planning, and achieve their goals more efficiently. …


Development And Investigation Of A Novel Near-Wall Methodology For Large-Eddy Simulation Based On Dynamic Hybrid Rans-Les, Michael Tullis May 2025

Development And Investigation Of A Novel Near-Wall Methodology For Large-Eddy Simulation Based On Dynamic Hybrid Rans-Les, Michael Tullis

Graduate Theses and Dissertations

The use of computational fluid dynamics (CFD) to test engineering designs with reduced cost and time compared to physical testing has become increasingly common in a range of industries and research fields. While numerical methods exist that can accurately solve the equations that govern the flow of fluids, these methods are computationally expensive for practical engineering problems due to the large amount of computational power needed to resolve the fluid flow over the entire range of length and time scales. Several different approaches have been introduced to address this computational cost issue, namely Reynolds-averaged Navier-Stokes (RANS) modeling and scale resolving …