Digital Commons Network^™

Analytical And Numerical Behavior Of Double Composite Steel Bridges, Emad M. Hassan, Hussam Mahmoud

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Steel plate girders are considered a viable solution for the construction of medium- to long-span bridges. Despite their many advantages, various concerns have been raised regarding their maintenance due to the potential of fatigue crack initiation at welded details, accelerated corrosion in thin webs, and trapped debris around stiffeners. The use of rolled beams, on the other hand, can be very beneficial because they require much less maintenance. However, they are limited in size, which imposes constraints on their use to relatively short-span bridges due to deflection requirements. In this study, the behavior of the double composite superstructure system was …

Measurement Of Volumetric Deformation, Strain Localization, And Shear Band Characterization During Triaxial Testing Using A Photogrammetry-Based Method, Sara Fayek, Xiong Zhang, Xiaolong Xia, Qingqing Fu, Jeffrey D. Cawlfield

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Triaxial Testing Has Been Routinely Used as a Standard Laboratory Test that Allows Correct Determination of Soil Characteristics. Previously the Volumetric Strain of the Triaxial Specimen Was Considered to Be Uniformly Distributed Along with the Specimen during the Isotropic and Deviatoric Loading. Although This Assumption Might Hold True under Isotropic Loading, the Effects of Restrained Ends and Disturbance during the Procedures of Specimen Installation and Testing Can Cause Nonuniform Strains throughout the Whole Specimen. This Paper Investigates the Effects of Specimen Preparation and Misalignment on the Strain Uniformity Along with the Soil Specimen during Triaxial Testing. a Series of Consolidated …

Analyzing Ground Motion Records With Cvi Fuzzy Art, Dustin Tanksley, Xinzhe Yuan, Genda Chen, Donald C. Wunsch

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper explores using Cluster Validity Indices Fuzzy Adaptative Resonance Theory (CVI Fuzzy ART) to cluster ground motion records (GMRs). Clustering the features extracted from a supervised network trained for predicting the structure damage results in less overfitting from the trained network. Using Cluster Validity Indices (CVIs) to evaluate the clustering gives feedback to how well the data is being classified, allowing further separation of the data. By using CVI Fuzzy ART in combination with features extracted from a trained Convolutional Neural Network (CNN), we were able to form additional clusters in the data. Within the primary clusters, accuracy was …

Approximation Of Optimal Control Surfaces For The Bass Model With Stochastic Dynamics, Gabriel Nicolosi, Christopher Griffin

Engineering Management and Systems Engineering Faculty Research & Creative Works

The Bass diffusion equation is a well-known and established modeling approach for describing new product adoption in a competitive market. This model also describes diffusion phenomena in various contexts: infectious disease spread modeling and estimation, rumor spread on social networks, prediction of renewable energy technology markets, among others. Most of these models, however, consider a deterministic trajectory of the associated state variable (e.g., market-share). In reality, the diffusion process is subject to noise, and a stochastic component must be added to the state dynamics. The stochastic Bass model has also been studied in many areas, such as energy markets and …

Usdot Tier-1 University Transportation Center For Advancing Cybersecurity Research And Education, Yunpeng Jack Zhang, Kailai Wang, Lingguang Song, Amaury Lendasse, Houbing Herbert Song, Zhu Han, Rakesh Verma, Arlei Silva, Carlos Rubio-Medrano, Zhixia Richard Li, Guohui Zhang

Engineering Management and Systems Engineering Faculty Research & Creative Works

The Transportation Cybersecurity Center for Advanced Research and Education (Cyber-Care) is a Us Department of Transportation (Usdot) Tier-1 University Transportation Center (Utc) Funded in 2023. Cyber-Care Primarily Focuses on the Usdot Statutory Research Priority Area of 'reducing Transportation Cybersecurity Risks.' Cyber-Care Aims to Establish a Fundamental Knowledge Basis and Explore Advanced Theory to Mitigate the Impacts of Large-Scale Cyberattacks on Transportation Infrastructure and Connected and Automated Vehicle (Cav) Systems. the Research Projects at Cyber-Care Will Develop Conceptual Frameworks, Construct Comprehensive Datasets, Explore Novel Analytical Approaches, Support the Implementation of Public Policies and Infrastructure Investments, and Build a High-Quality Industry Workforce …

Leveraging Targeted Regions Of Interest By Analyzing Code Comprehension With Ai-Enabled Eye-Tracking, Md Shakil Hossain

College of Graduate Studies: Theses & Dissertations

Code comprehension studies techniques for extracting information that give insights on how code is understood. For educators teaching programming courses, this is an important but often difficult task, especially given the challenges of large class sizes, limited time, and grading resources. By analyzing where a student looks during a code comprehension task, instructors can gain insights into what information the student deems important and assess whether they are looking in the right areas of the code. The proportion of time spent viewing a part of the code is also a useful indicator of the student's decision-making process. The goal of …

Developing Best Practices For The Propagation Of Spartina Alterniflora For Use In Salt Marsh Restortaion, Justin Hinson

College of Graduate Studies: Theses & Dissertations

Coastal salt marshes are valuable ecosystems under threat from climate change and sea level rise. Living shorelines offer a promising solution, often incorporating the foundational salt marsh species Spartina alterniflora due to its ability to tolerate natural stressors and maintain sediment stability. However, research suggests that seed-based propagation protocols should be developed on a local scale due to the genetic heterogeneity within and between S. alterniflora populations. Here, we attempt to contribute to the development of one such protocol for coastal Georgia S. alterniflora.

In Fall 2021, seeds were collected bi-monthly from four marshes of varying ocean proximity and …

A Camera-Only Based Approach To Traffic Parameter Estimation Using Mobile Observer Methods, Temitope D. Jegede

College of Graduate Studies: Theses & Dissertations

As vehicles become more modern, a large majority of vehicles on the road will have the required sensors to smoothly interact with other vehicles and infrastructure on the road. There will be many benefits of this new connectivity between vehicles on the road but one of the most profound improvements will be in the area of road accident prevention. Vehicles will be able to share information vital to road safety to oncoming vehicles and vehicles that are occluded so they do not have a direct line of sight to see a pedestrian or another vehicle on the road.

Another advantage …

Predicting Online Course Success From Usage Of An Online Tutoring System, Brett Miles

College of Graduate Studies: Theses & Dissertations

As online learning continues to grow in higher education, quality online support services must also be offered in order to meet the needs of online students. This study sought to investigate the relationship between the use of an outsourced online tutoring system and course success in select University System of Georgia eCore introductory online gateway courses to determine the extent of the relationship between tutoring usage and course success. The researcher employed logistic regression analysis to determine if using online tutoring increased the students’ probability for course success. Further, the researcher also studied the amount of usage to understand if …

Predicting Jamming Systems Frequency Hopping Sequences Using Artificial Neural Networks, Charles Strickland

College of Graduate Studies: Theses & Dissertations

This work proposes a neural network architecture that was designed to predict and reverse engineer frequency hopping jamming systems. The neural network was initially optimized for use with a 12th order linear shift feedback register maximum length sequence utilizing a minimal polynomial as the characteristic polynomial. This neural network was then scaled to accommodate 7 different sequences, of orders 6 through 12. The neural network was trained for these sequences using training data that is 10 times the length of the sequence. This information is then used to generate a hopping sequence that reduces the jamming interference to 0 with …

Fabrication And Investigation Of Microfluidic Devices That Produce Non-Linear Chemical Gradients, Elijah L. Waters

College of Graduate Studies: Theses & Dissertations

Investigation of cell chemotaxis requires controlled chemical gradients. We investigated microfluidic devices that could enhance small populations' cell assays because of their ability to generate various chemical gradients. Our five designs generate different chemical concentration landscapes that we can easily convert into tools to study cell response to growth factors. Gradient landscapes occurred by splitting and mixing two input fluid concentrations using bifurcations, trifurcations, and Y-mixing junctions in three consecutive steps. Such fluid flow manipulations resulted in nine concentration streams entering a 0.54-mm-wide gradient chamber. The first design used a 1:1 ratio Y-mixer (unbiased) when blending two concentrations, resulting in …

The Influence Of Urban Forms And Street Infrastructure On Pedestrian-Motorist Collisions, Taylor J. Foreman

College of Graduate Studies: Theses & Dissertations

Unwalkable cities are afflicted by serious issues such as increasing rates of pedestrian traffic accidents, public health concerns, and the denied right to have an accessible city. This study examines how different types of urban forms and street infrastructure contribute to the prevalence of traffic accidents in two major metropolitan cities in the United States: Atlanta, Georgia, and Boston, Massachusetts. This study utilizes geospatial analysis through the Average Nearest Neighbor and Optimized Hot Spot Analysis tools to determine the spatial distribution of traffic accidents throughout both cities. Additionally, statistical tests were conducted to explore the relationships between the number of …

Hepatic Transcriptomic Assessment Of Sprague Dawley Rats In Response To Dietary Perfluorobutane Sulfonate (Pfbs) Ingestion, Isaac Appiah

College of Graduate Studies: Theses & Dissertations

Perfluorobutane sulfonate (PFBS) is a short-chain PFAS that is considered to be a less toxic replacement for the rather more toxic long-chain perfluorooctane sulfonate (PFOS). Its numerous industrial applications and widespread presence in the environment have raised environmental and health concerns because of growing evidence associating adverse health effects and certain liver diseases to PFBS exposure. The study goal was to investigate whether dietary ingestion of PFBS would induce liver injuries, damage, inflammations, and oxidative stress. To achieve these goals, Sprague-Dawley rats were assigned into three PFBS dietary treatment groups (0, 50, and 100 PPM) for 11 weeks. After this …

Predictions Of The Dynamic Complex Modulus Of Non-Conventional Asphalt Concrete Using Machine Learning Techniques, Annie Benson

College of Graduate Studies: Theses & Dissertations

The complex dynamic modulus (|E*|) is a characterization property that defines the stiffness of an asphalt mixture. The dynamic modulus can be found through lab testing or predictions. Since lab testing can be time-consuming and expensive, the prediction method can be used as an alternative method. While a statistical method has been traditionally used for the |E*| prediction such as the Witczak’s predictive equations, machine learning (ML) is recently emerging as an alternative way that |E*| predictions can be made. This research attempted to predict the |E*| using several ML techniques including linear regression, support vector machines (SVM), decision trees, …

It's Not A Phobia: Reducing Transnegativity Using Imagined Intergroup Contact, Rachel Cook

College of Graduate Studies: Theses & Dissertations

The present study evaluated the efficacy of a novel imagined intergroup contact procedure in reducing feelings of transnegativity held by cisgender individuals. The intervention, based on the Fast Friends Procedure (Aron et al., 1997), has participants interact with a fictional transgender person who answers questions about himself; participants then write a free-response answer to the question for themselves. The current hypotheses were that the imagined intergroup contact procedure would (1) reduce feelings of transnegativity, (2) reduce feelings of contact apprehension toward transgender people, and (3) increase feelings of self-other overlap between cisgender people and a transgender target. In Study 1, …

Comparative Analytics On Chilli Plant Disease Using Machine Learning Techniques, Sai Abhishta Roy Seelam

College of Graduate Studies: Theses & Dissertations

This thesis concerns the detection of diseases in chilli plants using machine learning techniques. Three algorithms, viz., Convolutional Neural Network (CNN), Recurrent Neural Network (RNN), and Multi-Layer Perceptron (MLP), and their variants have been employed. Chilli-producing countries, India, Mexico, China, Indonesia, Spain, the United States, and Turkey. India has the world’s largest chilli production of about 49% (according to 2020). Andhra Pradesh (Guntur) is the largest market in India, where their varieties are more popular for pungency and color. This study classifies five kinds of diseases that affect the chilli, namely, leaf spot, whitefly, yellowish, healthy, and leaf curl. A …

Endogenous Antioxidant Response And Lipid Peroxidation Levels In Muscle Tissue Of The Cownose Ray (Rhinoptera Bonasus), Bailey Berry

College of Graduate Studies: Theses & Dissertations

Oxidative stress is the result of an imbalance between reactive oxygen species (ROS) and antioxidant response within cells. ROS generation is a natural consequence of ETC activity within the mitochondria and is associated with aerobic metabolism. Oxidative stress data on elasmobranch muscle is limited, with previous studies primarily focusing on mammalian and teleost muscle. Elasmobranch skeletal muscle is generally composed of large proportions of white muscle fibers (anaerobic), low proportions of red muscle fibers (aerobic), and low proportions of pink muscle fibers (anaerobic). The cownose ray, a benthopelagic batoid species, presents an interesting model of study because it contains relatively …

A Comparison Of Tung Oil Resin Reinforcements Using Fibrous Proteins And Peptides For Biological And Materials Applications, Parker L. Williams

College of Graduate Studies: Theses & Dissertations

In this study a tung oil based thermoset was reinforced with collagen and fibroin, and the resulting composites were analyzed for their physical properties. Tung tree seed oil is a great candidate for biobased polymer production because its triglycerides are primarily made of alpha eleostearic acid, a fatty acid with three conjugated carbon-carbon double bonds. These double bonds allow for mechanically strong crosslinking in the polymer. It has been observed that polymerized tung oil forms a gel. This issue has been addressed using divinylbenzene (DVB) and n-butyl methacrylate (BMA) as co-monomers. Similar bio-based polymers have been studied and tend to …

Development And Praxis Of Ph Drug Delivery System Contra Zika, Julissa Rodriguez

College of Graduate Studies: Theses & Dissertations

As the effects of global warming continue to spread throughout the world, another critical issue is slowly gaining attention in many urban tropical countries. The Emerging Infectious Diseases/ Pathogens list from the National Institutes of Health (NIH) listed the Zika virus as a potential pandemic threat. In 2015, an outbreak of Zika was noted in several South American countries until the spread reached an all-time high of 87 countries in 2017. During the outbreaks, adults affected were noted to have joint and muscle pains, fevers, and rashes. The worst cases reported would ultimately lead to Guillain-Barre symptoms. Still, pregnant women …

Comparison Marker-Based And Markerless Motion Capture Systems In Gait Biomechanics During Running, Hui Tang

College of Graduate Studies: Theses & Dissertations

Background: Markerless (ML) motion capture systems have recently become available for biomechanics applications. Evidence has indicated the potential feasibility of using an ML system to analyze lower extremity kinematics. However, no research examined ML systems’ estimation of the lower extremity joint moments and powers. Objectives: This study primarily aimed to compare lower extremity joint moments and powers estimated by marker-based (MB) and ML motion capture systems during treadmill running. The secondary purpose was to investigate if movement’s speed would affect the ML’s performance. Methods: Sixteen volunteers ran on a treadmill for 120 s for each trial at the speed of …

Strengthening The Academic Progress Of Students Within Multi-Tiered Systems Of Support, Leslie Dial

College of Graduate Studies: Theses & Dissertations

Leadership in education is thinking, communicating, and modeling to maximize student growth and achievement. This quantitative research study explored how leadership can strengthen the academic progress of students within Multi-Tiered Systems of Support (MTSS). When implementation of MTSS is guided by adaptive school leadership, educators will be prepared, communication will occur, interventions will be established, and data will be evaluated. Adaptive leaders who build efficacy will ensure fidelity and continuous improvement of student achievement.

Survey research was conducted to analyze the operational level of MTSS regarding the domains of Leadership, Building Capacity for Instruction, Communication and Collaboration, Data-Based Problem-Solving, Tiered …

Executive Function & Self-Regulation In Preschool Age Children: Mindfulness Intervention, Larissa Lamarca

College of Graduate Studies: Theses & Dissertations

Executive function is an umbrella term used in psychology to define a number of cognitive processes that are important for success in daily life. Both self-awareness, being able to focus one’s thoughts and behavior, and self-regulation, being able to manage emotional and behavioral responses, are important components of executive function. Between three- and five-years of age, children begin developing such skills rapidly which are necessary for school readiness. This study recruited children participants from four local preschools to test for improvement in attention and self-regulatory skills. Two schools completed a mindful yoga activity for five consecutive days, while a second …

New Women In The Old Dominion: Race And Gender In Progressive-Era Virginia, Rachel Scott

College of Graduate Studies: Theses & Dissertations

This thesis traces the development of Black and white Southern women’s pursuit of political power between the end of the Civil War and the ratification of the Nineteenth Amendment in 1920. Emancipation and the downfall of the antebellum planter aristocracy upset traditional Southern gender norms and opened new doors for women of both races in the political upheaval of Reconstruction. Though both Black and white women participated in the women’s club movement and joined women’s advocacy and charity groups following the Civil War, their work was distinctive both from each other and from other regional Progressive movements. The context of …

Campus Safety Data Gathering, Classification, And Ranking Based On Clery-Act Reports, Walaa F. Abo Elenin

College of Graduate Studies: Theses & Dissertations

Most existing campus safety rankings are based on criminal incident history with minimal or no consideration of campus security conditions and standard safety measures. Campus safety information published by universities/colleges is usually conceptual/qualitative and not quantitative and are based-on criminal records of these campuses. Thus, no explicit and trusted ranking method for these campuses considers the level of compliance with the standard safety measures. A quantitative safety measure is important to compare different campuses easily and to learn about specific campus safety conditions.

In this thesis, we utilize Clery-Act reports of campuses to automatically analyze their safety conditions and generate …

Computational And Experimental Investigation Of Mass Reduced Aircraft Wing Ribs, Charles R. Fricks Iii

College of Graduate Studies: Theses & Dissertations

This study seeks to develop and evaluate a novel design of mass reduced aircraft wing ribs through the topology optimization method. For comparison, the same examination is performed on ribs with normal internal geometry. The wing rib design is based on that of the Gulfstream G650 transonic jet. The rib was divided into three segments for analysis based around the positions of the two spars. Only the center section of the rib (that being between the forward and aft spars) is mass optimized, while the leading and trailing edges of the ribs (outside the spars) will be kept solid for …

The Use Of The Pile Driving Analyzer For Piles Seated On Rock, William Eason

College of Graduate Studies: Theses & Dissertations

The PDA Test has been used for mostly driven piles since the 1970s. The PDA test gets the capacity of the pile by measuring the displacement of the pile being driven into the ground by using sensors called accelerometers. For the case in Georgia, the pile is sitting on the rock and being struck by the hammer selected. This pile sits on a hole that is already pre-drilled into the ground. There are concerns when striking the pile on hard rock such as damaging the pile because of too much hammer energy or other safety concerns in the field that …

Relationship Between School Climate And Student Achievement In Middle Schools, Brad Boykin

College of Graduate Studies: Theses & Dissertations

Administrators are charged with making decisions and implementing strategies to improve a school’s climate and student achievement. Because school climate and student achievement are interrelated, it would benefit administrators to understand which areas of school climate have the greatest impact on student achievement. The State of Georgia measures school climate and achievement with its school accountability measure, College and Career Ready Performance Index (CCRPI). This study employed a quantitative research design using archival data from CCRPI over two years to examine the relationship between school climate and student achievement. The researcher used Pearson’s r correlation and multiple regression analysis to …

Using Machine Learning Classification And Esa Sentinel 2 Multispectral Imager Data To Delineate Marsh Vegetation And Measure Ecotone Movement In Coastal Georgia, Thomas A. Pudil

College of Graduate Studies: Theses & Dissertations

Tidal marshes are unique communities that are subjected to environmental stressors including sea level rise, salinity change, and drought, resulting in constant change. It is important to monitor these changing areas because of the ecosystem services they provide to us, such as protection from storms and carbon sequestration. The proposed work for this thesis project is focused on the study of tidal marshes and the dynamics between the vegetation species within them. The aim of this project is to use geospatial technology and analyses, along with machine learning classification methods, to monitor change in these valuable ecosystems. The Georgia coast …

Remote Sensing Of Georgia Tidal Marsh Habitats Using Aerial Photography And Planetscope Satellite Imagery, Harrison M. Currin

College of Graduate Studies: Theses & Dissertations

Globally, tidal marshes cover about 90,800 km. Within the state of Georgia tidal marshes are primarily located behind the barrier islands and total 1,619 km². The combination of high salinity environments and daily inundation, and being dependent on river output, make these dynamic systems. Tidal marshes provide numerous ecosystem services such as carbon and nitrogen sequestration, flood control, coastal protection, and numerous biogeochemical processes. Due to their unique position, tidal marshes are under threat from sea level rise, drought, coastal development, and large-scale disturbance events. Tidal freshwater marshes are especially susceptible to these threats due to their geographic …

The Effects Of Cucurbitacin B And Silmitasertib On Metastasis And Itga6 Using The Zebrafish Tumor-Xenograft, Alexandra Griffis

College of Graduate Studies: Theses & Dissertations

Ninety percent of cancer deaths are resultant from the metastasis of cancer cells. When cancer cells translocate through blood vessels or the lymphatic system, they may form tumors outside of their primary site. The processes of metastasis can begin quickly; after onset, metastasis is unforgiving, as it does not participate with the body’s physiological systems in an orderly way. In the past, our lab produced results indicating that a cell adhesion molecule, Integrin Alpha-6, may contribute to cancer cells' ability to metastasize. Integrins mediate interactions between the cell and the Extracellular Matrix (ECM), regulating cell attachment and cell migration. With …