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Flood Inundation Mapping Of The Catalpa Creek Watershed, Subodh Poudel Dec 2023

Flood Inundation Mapping Of The Catalpa Creek Watershed, Subodh Poudel

Theses and Dissertations

This study addresses flood risk assessment in the Catalpa Creek watershed, located in northeast Mississippi, USA. Employing the Hydrological Modeling System (HEC-HMS) and the River Analysis System (HEC-RAS), integrated models were developed and calibrated, to predict flood behavior within the watershed. The study conducted flood frequency analyses for return periods ranging from 2 to 100 years and generated flood inundation maps, pinpointing flood-prone areas. Mitigation measures for flood risk management were recommended. The results underscore the effectiveness of the integrated modeling approach for simulating and understanding the complex dynamics of flood events. The research identified critical flood-prone zones, emphasizing the …


Membrane Fabrication And Functionalization For Improved Removal Of Monovalent Ions From Water Using Electrodialysis, Matthew P. Sheorn Dec 2023

Membrane Fabrication And Functionalization For Improved Removal Of Monovalent Ions From Water Using Electrodialysis, Matthew P. Sheorn

Theses and Dissertations

Electrodialysis is a membrane separation process that uses an electrical potential to drive the separation. The performance of these systems is largely based on the performance of their ion exchange membranes (IEMs). This research focused on enhancing the performance of IEMs for electrodialysis through surface modification techniques involving chitosan bonded to the surface of commercially available cation exchange membranes (CEMs). The surface functionalization techniques resulted in membranes with improved electrodialysis performance. This research also explored the processing framework to produce functionalized sulfonated PEEK (sPEEK) nanofibers for future consideration as cation exchange membranes.

Chitin was deacetylated to form the functionalized biopolymer …


Visual Acquisition And Detection Of Manned Fixed-Wing Aircraft And Rotorcraft: An Analysis Of Pilots' Perception And Performance, Rania Bassou Dec 2023

Visual Acquisition And Detection Of Manned Fixed-Wing Aircraft And Rotorcraft: An Analysis Of Pilots' Perception And Performance, Rania Bassou

Theses and Dissertations

In recent years, the rapid advancement of Unmanned Aircraft Systems (UAS) has led to an increasingly complex National Airspace System (NAS), necessitating a comprehensive understanding of factors that impact pilot visual acquisition and detection of other aircraft (including manned fixed-wing, rotorcraft, and UAS). The objective of this study is to investigate factors that affect pilot performance in visually acquiring and detecting other manned-fixed wing aircraft and manned rotorcraft using a multi-method approach, incorporating qualitative and quantitative data analysis. A diverse sample of pilots with varying flight experience participated in the study. Participants were exposed to a series of flight test …


“I Tell It Like It Is, Then How It Could Be”: Public Discourse And Public Administration In Popular American Music Since The 1990s, Kristen Dechert Dec 2023

“I Tell It Like It Is, Then How It Could Be”: Public Discourse And Public Administration In Popular American Music Since The 1990s, Kristen Dechert

Theses and Dissertations

This study is an analysis of lyrics from popular American music albums since the 1990s to understand public discourse about and experience with public administration. Albums included in the study came from two prominent sources: Billboard and Pitchfork decade-end lists. The study is framed by critical, postmodern, and responsiveness theories, methodologically grounded in critical discourse analysis, and technically approached using standard qualitative methods, including especially qualitative content analysis and iterative, inductive coding techniques. Findings from the qualitative study demonstrate public discourse on the themes of institutional and systemic racism and violence within and perpetuated by public administration and public institutions. …


Assessing The Relationship Between Soil Health/Quality And Water Quality In The Mississippi Delta, Laura Andrea Sarmiento Rodriguez Dec 2023

Assessing The Relationship Between Soil Health/Quality And Water Quality In The Mississippi Delta, Laura Andrea Sarmiento Rodriguez

Theses and Dissertations

Several studies have reported agronomic benefits by improving soil health/quality, but uncertain knowledge remains when determining specific impacts on water quality off-field. This study investigated the links between runoff water quality and soil health/quality in agricultural fields of the Mississippi delta under three land management scenarios: Conservation Reserve Program (CRP), vegetative buffer (VB), and row crops (RC). Using the Soil Management Assessment Framework (SMAF), a Soil Quality Index (SQI) was obtained based on ten soil health/quality indicators from 2008 and 2012 datasets. The SMAF identified significant differences in soil health/quality improvements among scenarios over a four-year period. Varied relationships between …


Probing The Biophysical Interactions Between Autolysin Proteins And Polystyrene Surfaces, Radha Paramee Wadduwage Dec 2023

Probing The Biophysical Interactions Between Autolysin Proteins And Polystyrene Surfaces, Radha Paramee Wadduwage

Theses and Dissertations

Biofilms formed on medical devices pose significant challenges, compromising device efficiency and serving as sources of infection. Staphylococcus epidermidis, an opportunistic pathogen, relies on the autolysin protein, notably its R2ab and amidase domains, to attach to polystyrene surfaces and initiate biofilm formation. Despite their pivotal role, the structural intricacies of these proteins’ interactions with surfaces remain elusive. In this dissertation, the multifaceted aspects of protein interactions with polystyrene surfaces and the implications of these interactions for biofilm control are studied. Over the course of this study, it is found how the R2ab and amidase domains influence biofilm formation on polystyrene …


Study Of Augmentations On Historical Manuscripts Using Trocr, Erez Meoded Dec 2023

Study Of Augmentations On Historical Manuscripts Using Trocr, Erez Meoded

Theses and Dissertations

Historical manuscripts are an essential source of original content. For many reasons, it is hard to recognize these manuscripts as text. This thesis used a state-of-the-art Handwritten Text Recognizer, TrOCR, to recognize a 16th-century manuscript. TrOCR uses a vision transformer to encode the input images and a language transformer to decode them back to text. We showed that carefully preprocessed images and designed augmentations can improve the performance of TrOCR. We suggest an ensemble of augmented models to achieve an even better performance.


College Preparedness. Narratives Of Transitions From High School To College., Chelsey Luann Vincent Dec 2023

College Preparedness. Narratives Of Transitions From High School To College., Chelsey Luann Vincent

Theses and Dissertations

Despite many theories on student success as well as many resources to help students make the transition from high school to college, many students do not persist in or graduate from college. The purpose of this dissertation is to provide insight into what takes place when students leave P-12 institutions and enter institutions of higher education by using focused narrative inquiry. This study took place at a large research university in the south. The study included 4 participants at various parts of their transition journey. Participants in the study responded to written prompts. Follow up interviews were conducted, and a …


Electroencephalography And Biomechanics Of The Basketball Throw, Phong Ky Phan Dec 2023

Electroencephalography And Biomechanics Of The Basketball Throw, Phong Ky Phan

Theses and Dissertations

According to various studies, compared with novice athletes, experts exhibit superior integration of perceptual, cognitive, and motor skills. This superior ability has been associated with the focused and efficient organization of task-related neural networks. Specifically, skilled individuals demonstrate a spatially localized or relatively lower response in brain activity, characterized as ‘neural efficiency’, when performing within their domain of expertise. Previous works also suggested that elite basketball players can predict successful free throws more rapidly and accurately based on cues from body kinematics. These traits are the result of a prolonged training of specific motor skills and focused excitability of the …


High Temperature Materials From Bis-Ortho-Diynylarene (Boda)-Derived Resins And Perfluorocyclobutyl (Pfcb) Aryl Ether Polymers, Ernesto Isaac Borrego Dec 2023

High Temperature Materials From Bis-Ortho-Diynylarene (Boda)-Derived Resins And Perfluorocyclobutyl (Pfcb) Aryl Ether Polymers, Ernesto Isaac Borrego

Theses and Dissertations

This work expands the current understanding of materials chemistry and engineering capabilities of two synthetic platforms: 1.) bis-ortho-diynylarenes (BODA) and 2.) trifluorovinylaryl ethers (TFVE). Each platform possesses a unique chemistry which paradoxically enables the development of high-performance materials therefrom while simultaneously retaining exceptional melt and solution processability. Leveraging the apparent dichotomy in properties (performance/processability) obtainable from these two synthetics platforms, we have pursued and achieved a practical approach to high-temperature resistant materials with an immense potential for technology transfer and commercialization:

1.) BODA-derived resins (BDR) constitute a versatile platform of melt-processable resins capable of rapidly producing high performance …


Explainable Intrusion Detection Systems Using White Box Techniques, Jesse Ables Dec 2023

Explainable Intrusion Detection Systems Using White Box Techniques, Jesse Ables

Theses and Dissertations

Artificial Intelligence (AI) has found increasing application in various domains, revolutionizing problem-solving and data analysis. However, in decision-sensitive areas like Intrusion Detection Systems (IDS), trust and reliability are vital, posing challenges for traditional black box AI systems. These black box IDS, while accurate, lack transparency, making it difficult to understand the reasons behind their decisions. This dissertation explores the concept of eXplainable Intrusion Detection Systems (X-IDS), addressing the issue of trust in X-IDS. It explores the limitations of common black box IDS and the complexities of explainability methods, leading to the fundamental question of trusting explanations generated by black box …


Safety-Aware Autonomous Robot Navigation, Mapping And Control By Optimization Techniques, Tingjun Lei Dec 2023

Safety-Aware Autonomous Robot Navigation, Mapping And Control By Optimization Techniques, Tingjun Lei

Theses and Dissertations

The realm of autonomous robotics has seen impressive advancements in recent years, with robots taking on essential roles in various sectors, including disaster response, environmental monitoring, agriculture, and healthcare. As these highly intelligent machines continue to integrate into our daily lives, the pressing imperative is to elevate and refine their performance, enabling them to adeptly manage complex tasks with remarkable efficiency, adaptability, and keen decision-making abilities, all while prioritizing safety-aware navigation, mapping, and control systems. Ensuring the safety-awareness of these robotic systems is of paramount importance in their development and deployment. In this research, bio-inspired neural networks, nature-inspired intelligence, deep …


Designing An Artificial Immune Inspired Intrusion Detection System, William Hosier Anderson Dec 2023

Designing An Artificial Immune Inspired Intrusion Detection System, William Hosier Anderson

Theses and Dissertations

The domain of Intrusion Detection Systems (IDS) has witnessed growing interest in recent years due to the escalating threats posed by cyberattacks. As Internet of Things (IoT) becomes increasingly integrated into our every day lives, we widen our attack surface and expose more of our personal lives to risk. In the same way the Human Immune System (HIS) safeguards our physical self, a similar solution is needed to safeguard our digital self. This thesis presents the Artificial Immune inspired Intrusion Detection System (AIS-IDS), an IDS modeled after the HIS. This thesis proposes an architecture for AIS-IDS, instantiates an AIS-IDS model …


Design, Development, And Validation Of A Perfusion-Compression Bioreactor To Study Osteogenesis In Bone Explants, Alexis Victoria Graham Dec 2023

Design, Development, And Validation Of A Perfusion-Compression Bioreactor To Study Osteogenesis In Bone Explants, Alexis Victoria Graham

Theses and Dissertations

The current gold standard treatment for bone defects is autologous cancellous bone graft, which involves increased surgery time and donor site morbidity, and limited supply of bone and cells for regeneration. Bioreactors may aid in the generation of mechanically conditioned bone grafts with more cells compared to traditional grafts. However, the specific parameters of fluid flow and mechanical loading which contribute to osteogenesis and cell viability in bioreactors are not fully characterized. Here, a perfusion-compression bioreactor system was developed to study osteogenesis in porcine trabecular bone explants. Loading accuracy was over 88% across six bioreactors at a 0.1 s-1 strain …


Geospatial Integrated Urban Flood Mapping And Vulnerability Assessment, Md Tazmul Islam, Md Tazmul Islam Dec 2023

Geospatial Integrated Urban Flood Mapping And Vulnerability Assessment, Md Tazmul Islam, Md Tazmul Islam

Theses and Dissertations

Natural disasters like flooding have always been a big problem for countries around the world, but as the global climate changes and the number of people living in cities keeps growing, the threat of flooding has become a lot worse. Even though many studies have been conducted on flood mapping and vulnerability assessment in urban areas, this research addresses a significant knowledge gap in this domain. First, we used a flood depth estimation approach has been used to address the overestimation of urban flood mapping areas using Sentinel-1 images. Ten different combinations of the two initial VH and VV polarizations …


Green Wood Composites With Natural Preservatives, Thomas Frank Norman Dec 2023

Green Wood Composites With Natural Preservatives, Thomas Frank Norman

Theses and Dissertations

The purpose of this study is to test the mechanical, dimensional stability, and weathering durability of OSB (oriented strand board) panels that have been treated with varying natural wood preservatives that were chosen from an array of natural antimicrobial compounds. Wood is increasing in popularity for new construction projects but has been limited by its vulnerability to biological degradation. The addition of natural antimicrobial compounds will increase the use life of wood-based strand board allowing its use to expand with the growing construction demand but has little data on how natural antimicrobial compounds impact different properties of the OSB. The …


Mechanical Characterization Of Functionally Graded M300 Maraging Steel Cellular Structures, Bradley Jay Sampson Dec 2023

Mechanical Characterization Of Functionally Graded M300 Maraging Steel Cellular Structures, Bradley Jay Sampson

Theses and Dissertations

Traditional methods for increasing the energy absorption of a structure involve using a stronger material or increasing the volume of the structure, resulting in a higher cost or additional weight. Additive manufacturing (AM) can be used to maximize the energy absorption of materials with the ability to create complex geometries such as cellular structures. Previous work has shown that the energy absorption of additively manufactured parts can be improved through functionally graded cellular structures; however, this strategy has not been applied to ultra-high strength steel materials. This work characterizes the effect of multiple functional-grading strategies (e.g. uniform, rod-graded, size-graded) on …


Phenotyping Cotton Compactness Using Machine Learning And Uas Multispectral Imagery, Joshua Carl Waldbieser Dec 2023

Phenotyping Cotton Compactness Using Machine Learning And Uas Multispectral Imagery, Joshua Carl Waldbieser

Theses and Dissertations

Breeding compact cotton plants is desirable for many reasons, but current research for this is restricted by manual data collection. Using unmanned aircraft system imagery shows potential for high-throughput automation of this process. Using multispectral orthomosaics and ground truth measurements, I developed supervised models with a wide range of hyperparameters to predict three compactness traits. Extreme gradient boosting using a feature matrix as input was able to predict the height-related metric with R2=0.829 and RMSE=0.331. The breadth metrics require higher-detailed data and more complex models to predict accurately.


Increasing Graduate School Enrollment In A Shrinking Applicant Pool: A Look At Factors Influencing College Choice, Lindsey Erin Storey Shelton Dec 2023

Increasing Graduate School Enrollment In A Shrinking Applicant Pool: A Look At Factors Influencing College Choice, Lindsey Erin Storey Shelton

Theses and Dissertations

For years, the impending enrollment cliff has been a regular topic amongst higher education officials. With this event slated to hit undergraduate programs by 2025, it is anticipated that graduate schools will begin feeling the impact by 2029. By examining factors influencing graduate student college choice, enrollment managers can identify ways to offset the decline in eligible graduate students.

This study looked at applicants’ decisions to enroll or not enroll over a 5-year period at a public, research-intensive institution. The results of this study provided insight into the individual and academic factors that influence college choice, while also measuring the …


Exploring The Impact Of Extracurricular Activities On Adolescent Development: A Study Of Students Attending Schools In Poverty And Non-Poverty Areas, Clifton B. Thames Dec 2023

Exploring The Impact Of Extracurricular Activities On Adolescent Development: A Study Of Students Attending Schools In Poverty And Non-Poverty Areas, Clifton B. Thames

Theses and Dissertations

Previous literature has indicated a relationship between poverty, participation in extracurricular activities, and developmental outcomes. The current study aimed to investigate and develop a deeper understanding of extracurricular activities (ECAs) and their impacts on adolescent development using two self-report tools, the YES 2.0 and the Delinquent Attitude Scale (DAS). The researcher surveyed 174 high school seniors from students attending schools in poverty areas and students attending schools not located in poverty areas in Mississippi, examining disparities in ECA opportunities, barriers to participation, and the positive and negative impacts of ECAs on development. Additional data were collected from school administrators, allowing …


Towards Understanding The Interactions Between Ospreys And Human-Made Structures In The Tennessee River Valley, Natasha Karina Murphy Dec 2023

Towards Understanding The Interactions Between Ospreys And Human-Made Structures In The Tennessee River Valley, Natasha Karina Murphy

Theses and Dissertations

Raptor nests on human-built structures represent a significant source of conflict as they can result in bird mortality, fires, structure damage, service distribution, or power outages when falling nest materials or animals connect with energized conductors. Power companies, such as the Tennessee Valley Authority (TVA), wish to mitigate these conflicts to avoid service disruptions. In this dissertation, I present my work towards understanding and mitigating the interactions between Ospreys (Pandion haliaetus) and human-made structures. To achieve this, I explored multiple elements of conflict identification, monitoring, and basic ecology of the target species to better inform conflict mitigation. In Chapter I, …


Study Of Surface And Groundwater Quality And Quantity At Watershed Scale In Mississippi, Dipesh Nepal Dec 2023

Study Of Surface And Groundwater Quality And Quantity At Watershed Scale In Mississippi, Dipesh Nepal

Theses and Dissertations

Hydrology and water quality are affected by land use and climate changes. Mississippi’s diverse agro–ecosystem comprises of a range of land use land cover (LULC) including agriculture, forest, wetlands, urban, and grasslands. The objectives of this study were to investigate the impacts of various factors such as Best Management Practices (BMPs), wetlands, LULC, and climate changes on water quality and quantity. The hydrologic and water quality responses to dynamic LULC input in Soil and Water Assessment Tool (SWAT) were evaluated. Results showed that agricultural and forest expansion were major drivers of hydrologic and water quality changes in Big Sunflower River …


Moisture Effects On Visible Near-Infrared And Mid-Infrared Soil Spectra And Strategies To Mitigate The Impact For Predictive Modeling, Francis Hettige Chamika Anuradha Silva Dec 2023

Moisture Effects On Visible Near-Infrared And Mid-Infrared Soil Spectra And Strategies To Mitigate The Impact For Predictive Modeling, Francis Hettige Chamika Anuradha Silva

Theses and Dissertations

Instrumental disparities and soil moisture are two of the key limitations in implementing spectroscopic techniques in the field. This study sought to address these challenges through two objectives. The first objective was to assess Visible-near infrared (VisNIR) and mid-infrared (MIR) spectroscopic approaches and explore the feasibility of transferring calibration models between laboratory and portable spectrometers. The second objective addressed the challenge of soil moisture and its impact on spectra. The portable spectrometers demonstrated comparable performance to their laboratory-based counterparts in both regions. Spiking with extra-weight, was the most effective calibration transfer method eliminating disparities between instruments. The samples were rewetted …


Cement Stabilization Of Poorly Graded Sand, Lana Grayson Brown Sisung Dec 2023

Cement Stabilization Of Poorly Graded Sand, Lana Grayson Brown Sisung

Theses and Dissertations

Stabilization of poorly graded sand in full-scale applications is challenging. This thesis evaluated cement-stabilized sand and had two objectives: (1) evaluation of stabilized material using the PM device to quantify engineering properties for future comparison to alterative materials and to investigate the effectiveness of the device with sand and (2) investigation of the merits of alternative application of cement to sand to benchmark against other topically applied materials. The PM device was successfully used to recommend 10% cement for field studies with one sand, successfully allowed data collection in laboratory and field applications, and its potential in sand seems promising …


Development Of An Automated Delivery System To Apply Copper Sulfate Crystals Using Precision Dry Fertilizer Application Technology, Kevin Charles Wise Dec 2023

Development Of An Automated Delivery System To Apply Copper Sulfate Crystals Using Precision Dry Fertilizer Application Technology, Kevin Charles Wise

Theses and Dissertations

The digenetic trematode, Bolbophorus damnificus, poses a substantial threat to catfish aquaculture, causing significant economic losses. Infestations lead to suppressed feed consumption, secondary bacterial infections and poor production performance. Survey data reveals widespread infestation in the in the southeastern United States. Current control strategies involve the application of a concentrated copper sulfate solution to reduce snail populations which serve as the first intermediate host of the trematode life cycle. This study aimed to improve treatment efficacy by developing a granular copper sulfate application system. A modified Gandy fertilizer applicator, equipped with a programmable control system, demonstrated accurate distribution of copper …


Neural Networks For Improved Signal Source Enumeration And Localization With Unsteered Antenna Arrays, John T. Rogers Ii Dec 2023

Neural Networks For Improved Signal Source Enumeration And Localization With Unsteered Antenna Arrays, John T. Rogers Ii

Theses and Dissertations

Direction of Arrival estimation using unsteered antenna arrays, unlike mechanically scanned or phased arrays, requires complex algorithms which perform poorly with small aperture arrays or without a large number of observations, or snapshots. In general, these algorithms compute a sample covriance matrix to obtain the direction of arrival and some require a prior estimate of the number of signal sources. Herein, artificial neural network architectures are proposed which demonstrate improved estimation of the number of signal sources, the true signal covariance matrix, and the direction of arrival. The proposed number of source estimation network demonstrates robust performance in the case …


Identifying The Shortest Log Trucking Routes And Optimizing Those Constrained By Low-Weight Bridges In Mississippi, Swagat Attreya Dec 2023

Identifying The Shortest Log Trucking Routes And Optimizing Those Constrained By Low-Weight Bridges In Mississippi, Swagat Attreya

Theses and Dissertations

Timber haulage in Mississippi incurs the greatest portion of logging expenses because of a myriad of closed and posted (restricted) bridges. This study utilized Dijkstra's algorithm method in ArcGIS Pro to derive 129 feasible shortest optimal trucking routes between 46 harvest sites and 32 softwood sawmills in Mississippi. Among these routes, 30 of them had restricted bridges along the way; however, only 13 viable alternative routes were identified due to distance and weight restrictions. The additional trucking distance for alternative routes ranged between 1.5 to 12.9 miles, whose effect on transportation cost was determined using a Mixed Integer Linear Programming …


Advancing Air Filtration Analysis: A Comprehensive Approach To Particle Loading Models, Gentry Nathaniel Berry Dec 2023

Advancing Air Filtration Analysis: A Comprehensive Approach To Particle Loading Models, Gentry Nathaniel Berry

Theses and Dissertations

Fibrous air filters are commonly used to capture airborne particles due to their potential for a relatively high capture efficiency and low airflow resistance. Their performance characteristics make them ideal candidates in many instances, spanning a wide range from residential to sensitive industrial applications. However, as more particles are captured, the performance of the filter will evolve. This evolution of performance typically manifests as a higher capture efficiency and higher airflow resistance resulting from the additional particulate deposits. The prediction of fibrous filter performance has been the focus of research for many decades, resulting in numerous analytical, numerical, and empirical …


Scalable And Explainable Self-Supervised Motif Discovery In Temporal Data, Somayeh Bakhtiari Ramezani Dec 2023

Scalable And Explainable Self-Supervised Motif Discovery In Temporal Data, Somayeh Bakhtiari Ramezani

Theses and Dissertations

The availability of a scalable and explainable rule extraction technique via motif discovery is crucial for identifying the health states of a system. Such a technique can enable the creation of a repository of normal and abnormal states of the system and identify the system’s state as we receive data. In complex systems such as ECG, each activity session can consist of a long sequence of motifs that form different global structures. As a result, applying machine learning algorithms without first identifying the local patterns is not feasible and would result in low performance. Thus, extracting unique local motifs and …


A Conceptual Decentralized Identity Solution For State Government, Martin Duclos Dec 2023

A Conceptual Decentralized Identity Solution For State Government, Martin Duclos

Theses and Dissertations

In recent years, state governments, exemplified by Mississippi, have significantly expanded their online service offerings to reduce costs and improve efficiency. However, this shift has led to challenges in managing digital identities effectively, with multiple fragmented solutions in use. This paper proposes a Self-Sovereign Identity (SSI) framework based on distributed ledger technology. SSI grants individuals control over their digital identities, enhancing privacy and security without relying on a centralized authority. The contributions of this research include increased efficiency, improved privacy and security, enhanced user satisfaction, and reduced costs in state government digital identity management. The paper provides background on digital …