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2023

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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 …


Improved Methodology For Conducted Emi Assessment Of Power Electronics And Line Impedance Measurement, Mark Anthony Didat Dec 2023

Improved Methodology For Conducted Emi Assessment Of Power Electronics And Line Impedance Measurement, Mark Anthony Didat

Theses and Dissertations

Electromagnetic Interference (EMI), primarily common mode (CM), is problematic in a wide range of electronic circuits due to its propensity to radiate, particularly in high power applications. It is routine for much effort and resources to be dedicated to its characterization and reduction as EMI compliance is a requirement for most electronic systems and devices, including power electronics. Many well-known factors contribute to a system’s EMI performance including intentional coupling from system components as well as unintentional coupling from parasitics. Sources of intentional coupling may include Y-capacitors intended to mitigate EMI as part of a filter. Unintentional coupling is more …


Stream Water Quality Under Baseflow Conditions In A Livestock Production Area, Maryi Lorena Chavarro Chaux Dec 2023

Stream Water Quality Under Baseflow Conditions In A Livestock Production Area, Maryi Lorena Chavarro Chaux

Theses and Dissertations

This study evaluates the spatial and temporal impacts of implemented Best Management Practices (BMP) on stream water quality under baseflow conditions in a stream segment affected by livestock production. The BMPs includes 10-m fenced riparian zone and crossing paths along the reach segment. Grab water samples and water quality monitoring were collected biweekly from July 2019 to March 2022. Water quality parameters included temperature, dissolved oxygen, electric conductance, total dissolved solids, turbidity, and pH. Water samples were lab analyzed for sediments and nutrients. Results evidenced poor water quality before BMPs implementation, with nutrient concentrations exceeding the nation's and state's criteria. …


Condition Assessment Of The Northern Climatic Research House At The Usda Forest Service Forest Products Laboratory, Tanaya Johnson Dec 2023

Condition Assessment Of The Northern Climatic Research House At The Usda Forest Service Forest Products Laboratory, Tanaya Johnson

Theses and Dissertations

In 2001 a Northern Climatic Test House (the House) was constructed to demonstrate appropriate and novel building techniques and materials for the upper Midwest region of the USA. The House is a 2,300-square-foot, two-story structure located on the grounds of the USDA Forest Service Forest Products Laboratory (FPL) in Madison, Wisconsin. It is considered a research structure and not part of the FPL’s building inventory. Following construction, the House was heated and cooled but not occupied. Regular (sometimes daily) tours were conducted from it’s opening until about 2008, when tours had diminished to less than one per week. Since eliminating …


An Investigation Into Applications Of Canonical Polyadic Decomposition & Ensemble Learning In Forecasting Thermal Data Streams In Direct Laser Deposition Processes, Jonathan Storey Dec 2023

An Investigation Into Applications Of Canonical Polyadic Decomposition & Ensemble Learning In Forecasting Thermal Data Streams In Direct Laser Deposition Processes, Jonathan Storey

Theses and Dissertations

Additive manufacturing (AM) is a process of creating objects from 3D model data by adding layers of material. AM technologies present several advantages compared to traditional manufacturing technologies, such as producing less material waste and being capable of producing parts with greater geometric complexity. However, deficiencies in the printing process due to high process uncertainty can affect the microstructural properties of a fabricated part leading to defects. In metal AM, previous studies have linked defects in parts with melt pool temperature fluctuations, with the size of the melt pool and the scan pattern being key factors associated with part defects. …


Identifying Malware Similarity Through Token-Based And Semantic Code Clones, Christopher I. G. Lanclos Dec 2023

Identifying Malware Similarity Through Token-Based And Semantic Code Clones, Christopher I. G. Lanclos

Theses and Dissertations

Malware is the source or a catalyst for many of the attacks on our cyberspace. Malware analysts and other cybersecurity professionals are responsible for responding to and understanding attacks to mount a defense against the attacks in our cyberspace. The sheer amount of malware alone makes this a difficult task, but malware is also increasing in complexity. This research provides empirical evidence that a hybrid approach using token-based and semantic-based code clones can identify similarities between malware. In addition, the use of different normalization techniques and the use of undirected matrices versus directed matrices were studied. Lastly, the impact of …


Network Layer Reliability And Security In Energy Harvesting Wireless Sensor Networks, Jing Yang Dec 2023

Network Layer Reliability And Security In Energy Harvesting Wireless Sensor Networks, Jing Yang

Theses and Dissertations

Wireless sensor networks (WSNs) have become pivotal in precision agriculture, environmental monitoring, and smart healthcare applications. However, the challenges of energy consumption and security, particularly concerning the reliance on large battery-operated nodes, pose significant hurdles for these networks. Energy-harvesting wireless sensor networks (EH-WSNs) emerged as a solution, enabling nodes to replenish energy from the environment remotely. Yet, the transition to EH-WSNs brought forth new obstacles in ensuring reliable and secure data transmission.

In our initial study, we tackled the intermittent connectivity issue prevalent in EH-WSNs due to the dynamic behavior of energy harvesting nodes. Rapid shifts between ON and OFF …


Traffic Light Detection And V2i Communications Of An Autonomous Vehicle With The Traffic Light For An Effective Intersection Navigation Using Mavs Simulation, Mahfuzur Rahman Dec 2023

Traffic Light Detection And V2i Communications Of An Autonomous Vehicle With The Traffic Light For An Effective Intersection Navigation Using Mavs Simulation, Mahfuzur Rahman

Theses and Dissertations

Intersection Navigation plays a significant role in autonomous vehicle operation. This paper focuses on enhancing autonomous vehicle intersection navigation through advanced computer vision and Vehicle-to-Infrastructure (V2I) communication systems. The research unfolds in two phases. In the first phase, an approach utilizing YOLOv8s is proposed for precise traffic light detection and recognition, trained on the Small-Scale Traffic Light Dataset (S2TLD). The second phase establishes seamless connectivity between autonomous vehicles and traffic lights in a simulated Mississippi State University Autonomous Vehicle Simulation (MAVS) environment resembling a small city with multiple intersections. This V2I system enables the transmission of Signal Phase and Timing …


Evaluating Selected Properties Of Underutilized Hardwood Species For Fabrication Of Cross-Laminated Timber Industrial Mats, Mercy Itunu Ogunruku Dec 2023

Evaluating Selected Properties Of Underutilized Hardwood Species For Fabrication Of Cross-Laminated Timber Industrial Mats, Mercy Itunu Ogunruku

Theses and Dissertations

Softwood is more in demand than hardwood because it is used primarily in the US's largest wood-consuming industry, construction, resulting in increased importation of softwood annually to meet this demand. Hardwood, used for non-structural purposes like furniture and interior designs, is more abundant in US forests. However, some hardwood species are underutilized and undervalued. Cross-laminated timber (CLT) has increased the demand for softwood.

A study evaluated the mechanical and physical properties of three underutilized hardwood species (321 yellow poplar, 393 sweetgum, and 262 red oak specimens) for CLT industrial mat manufacturing. The results showed that red oak had a higher …


Modeling Compound Effects Of Earthquakes And Flooding On The Failure Probability Of Earthen Levees, Mohammad Reza Mahdavizadeh Dec 2023

Modeling Compound Effects Of Earthquakes And Flooding On The Failure Probability Of Earthen Levees, Mohammad Reza Mahdavizadeh

Theses and Dissertations

Earthen levees are crucial components of a nation's flood protection system. However, in some regions, these levees face the unique challenge of being subjected to both floods and earthquakes throughout their lifespan, an aspect that is relatively unexplored in the existing literature. The primary aim of this research is to examine earthquakes' and floods' effects on earthen levee failures. Using numerical simulations, the seepage, slope stability, and liquefaction potential of an earthen levee were modeled by considering compound of different floods and earthquakes scenarios. Elkhorn Levee in Sacramento, CA, was used as a representative case study for the simulations. The …


Improved Herbicide Selectivity In Tomato By Safening Action Of Benoxacor, 2,4,6-T, Melatonin, And Fenclorim, Tabata Raissa De Oliveira Dec 2023

Improved Herbicide Selectivity In Tomato By Safening Action Of Benoxacor, 2,4,6-T, Melatonin, And Fenclorim, Tabata Raissa De Oliveira

Theses and Dissertations

Safeners protect crops by enhancing their ability to metabolize various compounds, including herbicides. They primarily work by increasing the crop's tolerance to herbicide damage, activating herbicide-metabolizing proteins, and aiding in their detoxification. This study aimed to investigate the chemical effects of safeners in tomato cultivation and focus on injury reduction and tissue protection. The experiment followed a randomized factorial design (5x4) with four replications repeated twice. We evaluated the effects of herbicides (dicamba, 2,4-D, metribuzin, and sulfentrazone at 1/100) and safeners (benoxacor, fenclorim, melatonin, 2,4,6-T, and an untreated control). Safeners were applied to the seeds before sowing, and herbicides were …


Draft Final 2023 Butte Priority Soils Operable Unit Type B Borrow Material Submittal #1, Pioneer Technical Services, Inc. Dec 2023

Draft Final 2023 Butte Priority Soils Operable Unit Type B Borrow Material Submittal #1, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Draft Final 2023 Butte Priority Soils Operable Unit Type B Borrow Material Submittal #1, Pioneer Technical Services, Inc. Dec 2023

Draft Final 2023 Butte Priority Soils Operable Unit Type B Borrow Material Submittal #1, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Culturally Responsive Education: Creating A Safe And Inclusive Environment For Lgbtq+ Students, Kassidi M. Adams Dec 2023

Culturally Responsive Education: Creating A Safe And Inclusive Environment For Lgbtq+ Students, Kassidi M. Adams

Masters Projects

This paper explores research that discusses the impact of a culturally responsive education and lack-of for LGBTQ+ students and recommends a solution to ensure all students are safe and represented in schools. The research cited varies in their definitions and uses of the term LGBTQ+. This paper will use the term LGBTQ+, an abbreviation for lesbian, gay, bisexual, transgender, queer, and more communities; however, the abbreviation used in the referenced research may be shortened to LG, LGB, LGBT, or LGBTQ to reflect only specific communities included in LGBTTTQQIAAP (VandenBos, 2015). This paper will also focus on inclusion, which refers to …