Digital Commons Network^™

Unmanned Aerial Systems (Uas) Image Preprocessing To Reduce Artifacts And Improve Geometric Registration When Generating Orthophoto Mosaics And 3d Models, Eddie Ironsmith

Electronic Theses and Dissertations

Drones can now be used to quickly collect imagery data in a highly automated way; however, individual images must be combined to form an orthomosaic or 3-Dimentional (3D) model using photogrammetry software. Currently, the existing software may generate erroneous output in the form of artifacts or positional errors caused by homogeneous areas, light reflections, object movement between photos, or sub-optimal algorithms. The goal of this research was to develop preprocessing algorithms that would filter movement (or other time or position-based differences) and areas of homogeneity. The hypothesis is that filtering these parts of the image would reduce artifacts and improve …

Buried Pipeline Performance Under Surface Loading Using Finite Eelement Analyses And Innovative Soil Box Testing Methodologies., Adam Gabreil Cantrell

Electronic Theses and Dissertations

Buried pipelines are used extensively in the utility industry to deliver natural gas to customers. Reasonable estimates indicated that there are approximately 26,000,000 miles of pipeline, of various diameters throughout the United States (PHMSA, 2018). For protection, and to relieve urban congestion, these pipelines are nearly always buried under ground. After the pipes are installed, however, there is little opportunity for inspection, or for supplemental protection, when needed. Thus, to reduce the likelihood of rupturing a natural gas pipeline, design guidelines that ensure consistent, minimum protection of these utilities, have been developed and implemented. Pipeline design and installation regulations for …

Exploratory Learning In Two Modalities: Tabular Vs Graphical., Lianda Velic

Electronic Theses and Dissertations

In traditional educational settings, an instructor delivers a lecture prior to providing students a practice activity. Exploratory learning reverses this order to encourage active learning and engagement, typically improving learning outcomes. However, more research is needed in order to determine how to optimally design exploratory learning materials, and how differences in such design impact learning processes and outcomes. The current study investigated the impact of instructional order and activity modality type (tabular or graphical) on learning outcomes. Undergraduate students (N=252) were taught the statistical concept of consistency and the formula to compute standard deviation. In the instruct-first condition, …

Greek Key-Inspired Fractal Metamaterials With Enhanced Flexibility And Energy Absorption., Zhennan Zhang

Electronic Theses and Dissertations

Architected materials with intricate three-dimensional (3D) geometries offer unique properties and functionalities but face challenges in manufacturing costs and complexity. This research explores the integration of simple 2D Greek Key-inspired lattices into fractal designs to achieve exceptional mechanical performance. Using 3D printing and kerfing, these fractal structures demonstrate enhanced flexibility and energy absorption capabilities. Through three-point bending and in-plane tensile tests, the 2D fractal lattices exhibited a 600-fold reduction in bending force and a tensile stretch capacity of up to 520%, significantly outperforming brittle parent materials. Out-of-plane compression tests revealed a five-fold increase in energy absorption compared to honeycomb structures, …

Liquid Chromatography-Mass Spectrometry Based Metabolomics, Lipidomics And Epitranscriptomics., Raobo Xu

Electronic Theses and Dissertations

Metabolomics and lipidomics are the comprehensive studies of metabolites and lipids in cells, biological fluids, tissues, or organisms. These distinct chemical fingerprints are left behind by cellular processes. Epitranscriptomics is the field that focuses on examining chemical modifications on RNA molecules at the transcriptome level. Liquid chromatography-mass spectrometry (LC-MS) has been widely used in those omics studies. In this dissertation, I developed and applied both untargeted and targeted approaches using LC-MS based various analytical platforms to conduct omics studies. Firstly, I investigated caffeine metabolites in human urine and discovered three potential functional biomarkers to differentiate the stages of alcohol-associated liver …

A Little Bit Of Everything: Persistence Though The Pre-Medical Pipeline For First And Continuing Generation Students., Tana R. Didelot

Electronic Theses and Dissertations

This qualitative research study examines pre-medical college student persistence in their pathway to medical education. Through the framework of Terenzini and Reason’s College Student Persistence Model (2005), this work sought to understand the pre-college experiences, campus support factors, and external environments that help pre-medical college students to continue toward their goal of medical school entry. This study included pre-medical undergraduate students in the campus context of one public institution in the Southern Unites States. Pre-medical upperclassmen students were interviewed using a semi-structured protocol developed with the persistence framework. The analysis was conducted to obtain a more nuanced understanding of the …

Spectrum Optimization For Advanced Air Mobility Communications Using Deep Reinforcement Learning., Rafael D. Apaza

Electronic Theses and Dissertations

As aviation operations expand and new participants enter the National Airspace System (NAS), the demand for aeronautical communications will experience a significant rise. This surge is propelled by increased air travel and the emergence of Urban Air Mobility (UAM) operations, a subset of Advanced Air Mobility (AAM). UAM aims to facilitate intra-city transportation of people and cargo utilizing remotely piloted aircraft capable of electric vertical takeoff and landing operations. The growing dependence on efficient wireless communication systems underscores the critical importance of intelligent spectrum allocation and effective airspace management to ensure safe, seamless, and technologically advanced air operations. However, the …

How White Supremacy Travels Through Time: Anti-Literacy Laws, Dei Bans, And The Issue Of Black Self-Determination In Public Health., Nicole V. Ford

Electronic Theses and Dissertations

This dissertation used a qualitative policy content analysis (PCA) of historical anti-literacy laws and modern DEI bans to answer two research questions: What is the connection between anti-literacy laws and DEI bans? How do anti-literacy laws and DEI bans create an environment that maintains white supremacy? A PCA exercise informed the analysis of historical anti-literacy laws in South Carolina (1834), Georgia (1829), North Carolina (1830), Louisiana (1830), Virginia (1831), and Alabama (1833) and modern DEI bans in Texas (2023), Alabama (2024), and Florida (2023) to find the connection between the laws. Findings from this dissertation illustrate how white supremacy operates …

Development Of A Square Wave Voltage Field-Oriented Controller For A Linear Vapor Compressor., Thomas Everson

Electronic Theses and Dissertations

In this thesis, a novel control strategy for an inverter-driven linear compressor system is proposed in which the overall electrical losses of a coupled inverter-linear motor system are reduced through the use of a modified square wave inverter modulation scheme to minimize inverter switching losses at the expense of a modest increase in conduction losses. The controller is based on a single-phase field-oriented control strategy, and to achieve the FOC control objectives, the fundamental and dc components of the applied square wave voltage are matched to the corresponding values requested by the current controller. To validate the efficiency improvements offered …

Nickel Electrocatalysts On Carbon Supports For The Hydrogen Evolution Reaction., Mohan Paudel

Electronic Theses and Dissertations

Hydrogen is an important energy storage alternative to fossil fuels due to its high energy density. Currently, most hydrogen is produced through petroleum feedstocks, which produce large amounts of carbon dioxide. However, a more eco-friendly method is the electrocatalytic splitting of water into hydrogen and oxygen. Efficient catalysts for the hydrogen evolution reaction (HER) are typically platinum group metals, which are rare and expensive. There is growing interest in developing HER electrocatalysts with earth-abundant metals for water electrolysis. Nickel, which lies in the same group in the periodic table as Pt and has similar chemical properties, is explored extensively for …

Modeling And Understanding Of Additive Manufacturing Periodic Cellular Structures With Heterogeneity: Property, Quality And Design Strategy., Naresh Koju

Electronic Theses and Dissertations

Lightweight cellular structures with their higher per mass performance capability, multifunctional designability and property tolerability are gaining much wider adaptation in many engineering applications ranging from aerospace, defense, biomedical, automotive to sports. However, to achieve the desired performance levels careful design must be carried out. The experimental-based empirical design often involves high manufacturing cost, and there are also certain information/knowledges about the cellular deigns that could not be easily obtained experimentally, such as the deformation local fracture initiation. Similarly, numerical modeling-based design approach commonly suffers from high computation cost and the lack of inverse designability. In addition, numerical models often …

Teachers’ Perception Of School Counselors’ Effectiveness When Supporting Middle-Level African American Males, Vanessa Dease

Electronic Theses and Dissertations

Six teachers representing three sites in a single school district shared their perceptions through interviews regarding school counselors' effectiveness when supporting African American middle-level males academically, socially, and emotionally. A reflexive thematic analysis guided this study with the help of the sociocultural and expectancy theories. As participants shared their perceptions through interviews, they answered the three research questions that guided the research. The research questions are: (a) What are teachers' perceptions of the effectiveness of school counselors in addressing the unique social and emotional needs of African American male students? (b) What do educators expect of school counselors regarding supporting …

Early Career Teachers' Perceptions And Preparedness For Culturally Responsive Teaching When Teaching Black Youths With Behavior Challenges., Erica Brooks

Electronic Theses and Dissertations

In my study, I explore the perceptions and preparedness of early career teachers in the context of culturally responsive teaching (CRT) when instructing Black youth with behavior challenges. Early career teachers play a vital role in shaping the educational experiences of their students. Their beliefs and readiness to employ CRT practices are critical factors in addressing the unique needs of Black youth, particularly those facing behavioral difficulties. I investigated the perceptions of early career teachers regarding the importance of CRT and its effect on the learning environment. I examined how these teachers perceive the value of cultural responsiveness in managing …

Understanding Defect Dynamics In Black Phosphorene Under Noble Gas Ion Irradiation., Saransh Gupta

Electronic Theses and Dissertations

Controlled introduction of defects in phosphorene using high-energy ion beams offers a promising route to design novel high-performance materials for energy technologies. However, this potential remains underexplored due to a lack of fundamental understanding of the atomic-scale mechanisms governing the production, accumulation, and temporal evolution of defects during ion irradiation. Here, we employ a combination of classical and ab initio molecular dynamics simulations to elucidate the effects of ion energy, angle of incidence, noble gas ion size/mass, and fluence on (a) defect generation (i.e., point defects, topological imperfections, voids), (b) atomic-scale mechanisms of defect formation and re-arrangement, and (c) defect …

Investigating The Contribution Of First-Order Streams To Floods In Downstream Water Bodies On The Central Appalachian Plateau., Luke Ott

Electronic Theses and Dissertations

Flash floods are the costliest natural disaster in Appalachia. The goal of this study is to better understand flood response in headwater streams and the role of these systems in the generation of downstream floods. We applied a process-based hydrologic model using data from the Robinson Forest environmental monitoring network to estimate the contribution of headwaters to downstream floods. We then used the model to understand the effects of landscape disturbance in headwaters on downstream floods. Finally, we developed empirical hydrologic models to identify useful data for predicting downstream peak flood discharge. Results indicate that headwaters in our study catchment …

Detecting Anomalies In Dynamic Attributed Graphs: An Unsupervised Learning Approach, Austin Hamilton

Electronic Theses and Dissertations

Dynamic attributed graphs, which evolve over time and hold node-specific attributes, are essential in fields like social network analysis, where anomalous node detection is a growing area. Vehicular social networks (VSNs), a subset of these graphs, are ad hoc networks in which vehicles exchange data with one another and with infrastructure. In this dynamic context, identifying anomalous nodes is challenging but crucial for maintaining trust within the network. This work presents an unsupervised deep learning approach for anomalous node detection in VSNs. This model achieved an accuracy of 71% while detecting synthetic anomalies in a simulated network based on real-world …

An Exploration Of K-3 Teachers’ Beliefs, Attitudes, And Instructional Technology Use Pre-, During, And Post-Covid-19, Patience Mensah-Bonsu Aggrey

Electronic Theses and Dissertations

This qualitative multiple case study explores kindergarten to third-grade teachers use of instructional technology across three different periods: pre-COVID-19, during COVID-19, and post-COVID-19. This research investigates teachers’ attitudes, the use of technological tools by teachers, and the internal (second order) and external (first order) barriers that informed their use of instructional technology before and during the COVID-19 pandemic and continue to influence their use in the post-pandemic phase. Data were collected through questionnaires, interviews, and checklists from eight kindergarten third-grade teachers using a qualitative multiple case study approach. The findings suggest that there was a shift in teachers’ instructional technology …

Unraveling Phytosulfokine Trafficking In Arabidopsis Thaliana Using Fiber-Optic Fluorescence Microscopy, Issaka Obuaba

Electronic Theses and Dissertations

As sessile organisms, plants manage stress through complex signaling networks involving phytohormones such as phytosulfokine (PSK). PSK, a disulfated pentapeptide, regulates plant growth, development, and stress responses by interacting with specific PSK receptors (PSKRs). In this study, we explored the trafficking dynamics of PSK, its post-application fate, and the synthesis of an analog. We administered both native PSK and a fluorescent version tagged with TAMRA (5(6)-carboxytetramethylrhodamine) to various Arabidopsis thaliana genotypes, including wild type, a PSKR-deficient mutant, and a strain overexpressing PSKR1 tagged with green fluorescent protein (GFP) over the wild-type background. Fiber-optic fluorescence microscopy revealed that receptor presence influences …

Mapping Amis Mill In Rogersville, Tennessee In The 1780s Using Geophysical Methods And Remote Sensing, Amy Collins

Electronic Theses and Dissertations

Geophysics and remote sensing were used at the Amis Mill and Homesite to determine the location of structures during the 1780s. Areas of interest were surveyed using shallow geophysical and remote sensing techniques including the orchard, horse pasture, original kitchen on the east side of the house, the west side of the house, plowed field, store site, and cemetery. After analyzing the results of the geophysical surveys and remote sensing, 22 sites were chosen to test inside and outside potential features. A large rectangular feature, possibly a tavern with a cellar, was discovered. Four other features were identified, three of …

Educator Perceptions Of Career And Technical Education Courses And The Involvement In Career And Technical Student Organizations On Student Attendance, Robert Satterfield

Electronic Theses and Dissertations

The purpose of this study was to investigate the perceptions of secondary teachers, administrators, and educational supervisors of the implications of Career and Technical Education courses and the involvement in Career and Technical Student Organizations on student attendance. Data for this study were collected quantitatively by utilizing Microsoft Forms to administer the survey to potential participants. The survey administered for this study contained 13 Likert scale questions and two open-ended questions. Once data were collected SPSS Version 25 was used to analyze the data from the survey. After data analysis, it was concluded that all 13 of the Likert scale …

Overcoming The Barrier To The Clinical Application Of Naloxone: Application Of Drug Delivery Technologies, Akeemat O. Tijani

Electronic Theses and Dissertations

Opioid overdose crisis continues to demand innovative solutions for rapid and effective drug administration. Naloxone (NAL), a critical opioid antagonist, has been the primary treatment for reversing opioid-induced respiratory depression. However, its current delivery methods, such as intravenous and intranasal formulations, are limited by their invasive nature, short half-life, and the need for repeated dosing. This dissertation investigates advanced drug delivery technologies aimed at overcoming these challenges and enhancing the clinical utility of NAL.

This research focused on improving the transdermal and transnasal delivery of NAL using minimally invasive techniques. Various approaches were evaluated, including sonophoresis, microneedles, laser ablation, dermaplaning …

Landslide Inventory And Unstable Slope Monitoring Along Highways In Eastern Tennessee, Robert Mcsweeney

Electronic Theses and Dissertations

This research introduces an unstable slope management program (USMP) for Tennessee based on federal slope management standards, along with improved methods for landslide monitoring with unmanned aerial systems (UAS) lidar and photogrammetry. In mountainous regions, monitoring slope hazards is a critical function of transportation management. A mobile field assessment form created with Survey123 was used to collect 22 unstable slope ratings in eastern Tennessee. Location points were appended with photographs, notes, and site information. Landslide scores ranged from 325 (Fair) to 1005 (Poor). UAS monitoring of a slow-moving soil landslide along I-40 near Rockwood, TN, produced high-resolution lidar and photogrammetry …

Investigating Phytosulfokine Trafficking: Insights Into The Role Of Phytohormones In Plant Signaling, Martin Tindi

Electronic Theses and Dissertations

Phytosulfokine is a critical signaling peptide involved in plant growth, development, and stress responses. This thesis investigates the trafficking mechanisms of Phytosulfokine (PSK) in Arabidopsis thaliana, employing fluorescently labelled PSK for non-destructive imaging using a custom-built fiber-optic fluorescence microscope. The study aims to determine the mobility and fate of PSK in plant tissues. Experimental results reveal the short-range and long-range movement of PSK across leaves. Additionally, the project highlights the optimization of non-destructive imaging techniques and the synthesis of caged dexamethasone to facilitate optogenetic studies. These findings provide new insights into PSK trafficking mechanisms in plants, enhancing our understanding …

Service Provider Perceptions Of Systems Serving Individuals Experiencing Homelessness: A Needs Assessment And Strategic Plan In Johnson City, Tn, Opal Frye-Clark

Electronic Theses and Dissertations

This Integrated Learning Experience (ILE) investigates service providers' perceptions of Johnson City, Tennessee's homelessness services, aiming to inform a city-wide strategic plan for reduction. Employing a mixed-methods approach, the study gathered qualitative data through in-depth interviews with service providers in 2022 and quantitative data via a 2024 survey. The research focused on those directly involved in serving or significantly influencing the lives of individuals experiencing homelessness (IEH). Three key aims guided the investigation: (1) To analyze provider perspectives to identify community assets, opportunities, barriers, and unmet needs, informing a comprehensive needs assessment; (2) To refine these findings through SWOT analysis …

The Lived Experiences Of Women In Construction: Career Supporting Strategies, Cheryl Anne Loar Croall

Electronic Theses and Dissertations

Women are underrepresented in the United States construction industry, representing only 11% of the workforce, and this lack of diversity in the male-dominated occupation results in barriers to female career advancement. The problem is that women in construction experience obstacles to career progression due to gender work life balance, sexual harassment, and pay inequality; barriers such as these keep women out of leadership roles. Three recommended techniques to support women’s career progression in construction and combat barriers to career advancement include social support, fighting back (openly challenging discrimination), and positive reappraisal (reframing negatives to positives). Understanding the effectiveness of these …

The Relationship Between Salvinia Molesta Infestation And The Microbial Ecology Of Wetlands At Caddo Lake, Tx, Usa, Martin Hadsell

Electronic Theses and Dissertations

Wetlands are known to host many beneficial geochemical processes such as nutrient cycling and carbon sequestration. These processes are primarily driven by the microbial communities within a wetland. The establishment of non-native invasive species within wetlands has the potential to alter the once beneficial functionality of wetland microbial communities due to the sensitivity microbes have towards environmental changes. Because of this, several metagenomic studies have been conducted to assess microbial community response to aquatic plant invasion; however, there haven’t been any studies researching the influence of Salvinia molesta (D.S. Mitch.), commonly known as Giant Salvinia, on microbial communities. The goal …

Bioremediation Of Effluent Water In A Coal Ash Disposal Area: Optimizing Microbial Sulfate Reduction, Ryka Shea

Electronic Theses and Dissertations

Coal combustion residues (CCR) pose a serious environmental threat, even long after they are disposed of in specialized landfills, due to their complex composition and potential for leaching into waterways. This study focuses on the issue of elevated sulfate concentrations at the Martin Lake Steam Electric Station (MLSES) A-I Disposal Area in Panola County, Texas, where CCR are disposed of in a permanent landfill. Currently, this site is exceeding its regulatory limit of sulfate concentrations in its effluent and is in need of a cost-effective and sustainable solution to this problem. This research utilized benchtop experiments to investigate sulfate reducing …

Evaluating Trauma-Informed Design In A Mental Health Setting: A Community-Based Research Case Study, Marie Spence

Electronic Theses and Dissertations

This case study utilized a community-based research framework to explore how the Trauma-Informed Design framework can be implemented in a mental health setting. This study focused on the site of Empower Therapy Practice, a private mental health practice in the Denver Metro Area, to engage clients and staff to participate in advisory boards and inform the interior design of a new office space. To explore the application of Trauma-Informed Design, participants engaged in a variety of research activities, including an evaluative questionnaire, Photovoice, and focus group. Advisory board members identified various aspects of Trauma-Informed Design which meaningfully translate to therapeutic …

My Superpower: Research Collaborator Strategies Among Faculty Members Who Are First-Generation College Graduates, Faye Farmer

Electronic Theses and Dissertations

This inductive study examined the intersectional experience within research collaborations of tenure-track faculty who are both first-generation college graduate students and from racial and ethnic groups (as defined in the United States) that are underrepresented in STEM fields (as defined by the National Science Foundation). I interviewed twelve current and former faculty members from doctoral-granting universities in the United States. I used identity as the theoretical lens to explore research collaborations at the individual level. The interviews revealed three themes reflecting identity's role in selecting and being selected as a collaborator and working with a collaborator. The themes are: an …

Designing Customized Loss Functions For Training Deep Neural Networks, Ali Pourramezan Fard

Electronic Theses and Dissertations

This dissertation explores the critical role of loss functions in enhancing the predictive performance of deep machine learning models. Loss functions are an integral element of all the ongoing advances we witness daily in this domain. I design custom loss functions and their impacts on various machine learning tasks, particularly in computer vision.

In the first stage of my research, I aim to improve the prediction performance of deep learning models by providing them with more precise feedback associated with task requirements. This led me to create the concept of assistive loss functions. My first proposed loss function, inspired by …