Digital Commons Network^™

Math Anxiety And Performance Following Observational Learning And Performance Pressure, Michael G. Duthie

Theses

Past research demonstrated that a variety of factors contribute to the severity of math anxiety and its detriments on math performance. The present study examined the influence of performance pressure, sex, second-hand success or failure of a male or female, and problem difficulty on math anxiety and performance. The design included a 2 (Participant sex: male, female) x 2 (Student actor sex: male, female) x 2 (Video outcome: success, failure) x 2 (Problem difficulty: easy, difficult) x 2 (Pressure: low, high) mixed design. Participants (UAH students, n = 232) were recruited from introductory psychology courses and completed the study via …

Excitation Of The Dominant Transverse Electric Mode Of A Microstrip Patch Antenna Using A Coplanar L-Strip Feeding Technique, Matthew A. Adams

Theses

Microstrip patch antennas are employed in a variety of commercial and military applications due to their versatility, low profile, and ability to be easily fabricated. In this thesis, a microstrip patch antenna is made from artificial magnetic conductor (AMC) unit cells that excite the dominant transverse electric (TE) mode via an L-strip coplanar with the AMC patch layer. Integration of the L-strip into the unit cell layer of the AMC patch and the ground layer of the AMC patch is investigated and full-wave analyzed. To improve gain radiation pattern symmetry about the broadside direction, the AMC patch is shifted laterally …

Applying Data Science And Machine Learning Techniques For Hydrological Applications : Case Study In Cambodia, Biplov Bhandari

Theses

Cambodia suffers from flooding and flash-flooding events every year, and thus better flood management and forecasting are crucial in taking early action. The Streamflow Prediction Tool (SPT) provides forecast discharge 15 days in advance globally. This thesis applies data-driven and Machine Learning (ML) techniques to improve Cambodia’s hydrological applications. Two case studies are presented – the first predicts the river discharge from the water level using time-series information; the second uses the predicted discharge from the first to bias-correct the SPT’s historical reanalysis data using several ML techniques. The historical Bias Correction (BC) is the first step toward the forecasted …

Reinforcement Learning: Low Discrepancy Action Selection For Continuous States And Actions, Jedidiah Lindborg

College of Graduate Studies: Theses & Dissertations

In reinforcement learning the process of selecting an action during the exploration or exploitation stage is difficult to optimize. The purpose of this thesis is to create an action selection process for an agent by employing a low discrepancy action selection (LDAS) method. This should allow the agent to quickly determine the utility of its actions by prioritizing actions that are dissimilar to ones that it has already picked. In this way the learning process should be faster for the agent and result in more optimal policies.

The Ethicality And Political Skill Of Leaders And Subordinate Job Satisfaction: A Study Of Accounting Faculty, Donald L. Ariail

College of Graduate Studies: Theses & Dissertations

Using a sample of 539 accounting faculty teaching in the United States, this study explored perceptions of the ethicality and political skill of their direct supervisors and self-reported levels of job satisfaction. Ethicality was measured with the Ethical Leadership Scale (ELS) and the Behavioral Integrity (BI) Scale. These measures, which were highly correlated, were proxy measures for accounting faculty perceptions of the tone-at-the-top (TATT)—the ethical leadership under which faculty teach and research. The results indicated that while the majority of accounting faculty perceived their direct supervisor as being ethical, about a third (28% BI, 34.8% ELS) of them did not …

Ring Bose–Einstein Condensate Atomtronic Rotation Sensor, Oluwatobi I. Adeniji

College of Graduate Studies: Theses & Dissertations

We propose a design for an atomtronic rotation sensor consisting of an array of Bose– Einstein condensates (BECs) confined in a double–target–array potential. The purpose of the sensor is to measure the rotation speed, Ω_R, of the sensor’s rest frame with respect to the “fixed stars.” The atomtronic system consists of an ultracold gas of sodium atoms compressed, using laser light, into a thin horizontal sheet and subjected to a double–target– array potential within the horizontal plane. A “target” BEC consists of a disk–shaped condensate surrounded by a concentric ring–shaped condensate. A “double–target” BEC is two adjacent target …

Eeg Signals Classification Using Lstm-Based Models And Majority Logic, James A. Orgeron

College of Graduate Studies: Theses & Dissertations

The study of elecroencephalograms (EEGs) has gained enormous interest in the last decade with the increase of computational power and availability of EEG signals collected from various human activities or produced during medical tests. The applicability of analyzing EEG signals ranges from helping impaired people communicate or move (using appropriate medical equipment) to understanding people's feelings and detecting diseases.

We proposed new methodology and models for analyzing and classifying EEG signals collected from individuals observing visual stimuli. Our models rely on powerful Long-Short Term Memory (LSTM) Neural Network models, which are currently the state of the art models for performing …

Analysis Of Bio-Alcohols With Mie-Scattering And Ltc For Lowered Emissions In Pcci, Cesar E. Carapia

College of Graduate Studies: Theses & Dissertations

An investigation was conducted on the optimal engine parameters for facilitating lower NOX and soot emissions of PCCI combustion with either ethanol or n-butanol. The PFI fuels selected were tested at loads of 3, 4, and 5 Bar IMEP for a total of 28 total combustion tests with variations made to the EGR% and boost pressure for each test in order to find the optimal emissions strategy. A Mie-scattering spray fuel analysis was also conducted on the three fuels to gain insight on their influence on combustion/emissions characteristics. It was found that ethanol had a greater average Sauter Mean Diameter …

Molybdenum Oxide/Antimony Nanobelts Embedded In Asymmetric Membranes For Use As High-Capacity Lithium/Sodium-Ion Battery Anodes, Logan Williams

College of Graduate Studies: Theses & Dissertations

Lithium-ion batteries (LIB) are a key aspect of our daily lives, from smartphones to electric vehicles. Commercially available LIB use graphite anodes due to their reliability and safety. Graphite anodes present one key disadvantage: a relatively low theoretical capacity of 372 mAh g-1. It is of great importance that new research focuses on high-capacity anode materials to further our sustainability and usage of LIB. While increasing the performance of LIB is of great interest, developing alternative energy storage devices is gaining attention in academia and industry R&D. Sodium has become a topic of interest in recent years due to sodium’s …

Stop, Then Go! Rapid Acceleration Offsets The Costs Of Intermittent Locomotion When Turning In Florida Scrub Lizards, Cheyenne Walker

College of Graduate Studies: Theses & Dissertations

Intermittent locomotion is a commonly used escape strategy with a wide array of potential benefits. Pausing may aid in locating a predator, crypsis, lowering energy costs, and avoiding obstacles. Turning may also benefit from intermittent locomotion by allowing an animal time to assess its surroundings; therefore, decreasing the chances of making a mistake and/or stumbling. Florida scrub lizards live in environments with a variety of obstacles such as turns. The goal of this study is to quantify the locomotor behavior and performance by lizards while navigating a 45° or 90° turn. Lizards were run along both a 45° and 90° …

The Influence Of Faculty Peer Network Communication In The Diffusion Of A Centralized Cure, Nicole L. Scheuermann

College of Graduate Studies: Theses & Dissertations

Course-based undergraduate research experiences (CUREs) provide students the benefits of undergraduate research participation by incorporating authentic scientific research into laboratory courses. CUREs are a relatively young pedagogy and are therefore innovative. Roger’s (2003) diffusion of innovations (DOI) framework posits that the diffusion of innovations, such as CUREs, is a highly social process. Most existing CURE research has focused on the impacts to students and the critical elements of CURE design. Investigation into instructor peer network communication is largely absent from the existing CURE literature. This study investigates the structure and function of a CURE community – the Malate Dehydrogenase CURE …

Investigating The Effect Of A Facultative Symbiont, Hamiltonella Defensa, On Pea Aphid, Acyrthosiphon Pisum, Fecundity And Behavior In Elevated Co₂ Atmospheres, Tyler J. Follman

College of Graduate Studies: Theses & Dissertations

As atmospheric carbon dioxide (CO₂) levels continue to rise, it is important to study how economically important organisms, like the pea aphid, Acyrthosiphon pisum, will react to these conditions. The pea aphid feeds on the phloem of crop plants like alfalfa, peas, and fava beans, where it not only directly harms the plant but also can spread plant viruses. A wide variety of factors can influence pea aphid fecundity and behavior. Some of these factors are abiotic, like atmospheric conditions, and some are biotic, like microorganisms with which the pea aphid has a mutualistic relationship. In this thesis, …

Toward Novel Optical Functionalities Through Intelligent Photonic Structure Design, Robert J. Williamson

College of Graduate Studies: Theses & Dissertations

Photonic Metamaterials is a branch of electromagnetism that has been of great interest in recent years. This is further enhanced by the introduction of micro- and nanofabrication methods capable of producing metamaterial structures with which it is possible to create specific optical phenomena. The study of iso-frequency k-surfaces is of importance when discussing optical interactions with media. Previous research found evidence of materials exhibiting k-surfaces of bi-hyperbolic nature, though they failed to find any further hyperboloid dispersions. In this thesis we describe the k-surface topologies and including tri- and tetra-hyperbolic as well as analyze the polariton-interactions that cause these hyperbolic …

Using Ai-Enabled Gaze Tracking System To Understand Comprehension Patterns Of Computer Science Students, Bradley Boswell

College of Graduate Studies: Theses & Dissertations

Academic institutions and instructors lack the ability to accurately assess the moment-to-moment attentiveness of students in classrooms where students’ faces are obscured by computer monitors. This can cause the lectures of Computer Science, Information Technology, or other lab-based courses to be incorrectly-paced, which can lead to students having an overall poorer grasp of the subject material. We propose a system for real-time accurate detection of classroom attentiveness using monitor-mounted webcams and eye trackers, along with a Convolutional Neural Network machine learning model (NiCATS). Through the use of a neural network, we produce an initial attentiveness score based on student webcam …

The Synthesis And Biocatalytic Reduction Of Beta-Keto Alkynes, Rhema M. Francis

College of Graduate Studies: Theses & Dissertations

The preparation of enantiopure homopropargyl alcohols (but-3-yn-ols) is of high importance to the scientific community. They are employed as valuable pharmaceutical intermediates and are opportune to generate antiviral nucleoside analogues. Chiral inducement of these molecules thus far has been poor (low ee) and has constituted a key challenge for asymmetric synthesis in the last few decades. Enzyme-catalyzed enantioselective reductions of ketones have become popular to produce thus-prepared synthons on an industrial scale. Among them, biocatalysts (dehydrogenases, reductases) emerge as a biodegradable option for chemical transformations, in comparison to chiral catalysts that employ highly toxic metals. This research investigates the catalytic …

An Innovative Elastohydrodynamic Seal Concept For Gases, Matthew J. Demond

College of Graduate Studies: Theses & Dissertations

Supercritical CO₂ (sCO₂) power cycles are next generation power technologies offering improved efficiency, lower customer costs, and less water usage. They hold significant potential in many different industries such as nuclear power production, ship propulsion, geothermal power, solar power, and fossil fuel power plants. One of the largest hurdles preventing this milestone is the lack of suitable shaft seals for sCO₂ operating conditions. This component issue needs to be addressed for the next generation nuclear turbine and compressor development to progress. In this study, a novel Elastohydrodynamic (EHD) seal is proposed. This proposed design is capable …

Determining Cause Of Failure For Load Cells Supporting Vertical Pressure Vessels Subject To Wind Loading, Seth Nowak

College of Graduate Studies: Theses & Dissertations

Wind loads cannot be avoided during a natural disaster such as a hurricane and could affect the strength and stability of vertical pressure vessels during exposure. Vertical pressure vessels cater to large wind loads; therefore, it is imperative to study the effect of additional loading on the structures. In this study, three pressure vessels with volumes of 50 CuFt, 200 CuFt, and 1100 CuFt, supported by three equidistant load cells under their legs are individually analyzed to determine von mises stress to estimate yield failure criteria. Two load rating criteria, maximum load capacity and water-filled condition (critical condition) are utilized …

Non-Inferiority Testing: Kernel Estimation And Overlap Measure, Larie C. Ward

College of Graduate Studies: Theses & Dissertations

In non-inferiority testing, the decision of whether a proposed treatment is non-inferior to a reference treatment depends on model assumptions and choices of acceptable tolerance limits. Here, we consider a method that employs kernels to estimate the probability density functions of both the experimental and reference populations from two independent samples. Based on these densities, we introduce a quantity called the overlap coefficient or overlap measure. A bootstrap technique is helpful in exploring the distribution and variance empirically. We derive the distribution of this measure and define a hypothesis test that can be applied to the non-inferiority setting under some …

Voices Rising: Exploring The Tensions Of Homeschooled Women Defining Themselves Within A Religious Culture, Natalie S. Immings

College of Graduate Studies: Theses & Dissertations

Homeschooling is a familiar form of education, but nuances such as purposes, curriculum and impact on students are less understood due to minimal studies and lack of participation. Existing research has focused on motivations for homeschooling; however glaring gaps exist regarding the impact on student development. This study is essential due to concerns regarding the impact on student identity as well as the recent increase in the number of homeschoolers from a pandemic and other political trends. In an effort to pull back the curtain on the dominant conservative Christian homeschool milieu this study employed a qualitative ethnographic methodology which …

Impostorism On Campus: The Effects Of Stereotype Threat On State Inauthenticity And State Anxiety In Two Samples Of African American College Women, Gabrielle Y. Johnson

College of Graduate Studies: Theses & Dissertations

Despite the growing education levels of Black women, negative stereotypes of Black women persist and undermine the confidence of African American/Black college women in the classroom. Experimental evidence supports that stereotype threat, the fear of confirming a negative stereotype about one’s group when being evaluated by others, undermines the performance of high achieving Black students (Steele & Aronson, 1995). Research has found the impostor phenomenon to be experienced as thoughts of inauthenticity, in conjunction with fear of failure and being exposed as a fraud (Ibrahim et al., 2020). Therefore, being continuously exposed to situations that create feelings of state inauthenticity, …

Investigation Of Intramolecular And Intermolecular Aza-Michael Reactions, Nadia Z. Singleton

College of Graduate Studies: Theses & Dissertations

The hydroamination of dimaleimides with diamines has been accomplished to access novel polymers. Various dimaleamides and dimaleimides were synthesized from commercially available diamines and maleic anhydride. The resulting dimaleamides were then ring-closed to their respective dimaleimides either directly in the presence of acid or via the synthesis of mixed amide-esters which then ring close in the presence of acid under heat. Hydroamination of the dimaleimides with piperazine was accomplished in bulk at room temperature. The reaction is spontaneous thus leading to the formation of polyimides with high functional group conversion within minutes. The kinetics of the maleamides and maleimides was …

Synthesis Of Functionalized Aromatic Heterocyclic Compounds And Its Applications In Organized Self-Assemblies, Emmanuel T. Fasusi

College of Graduate Studies: Theses & Dissertations

1,2,3-triazoles due to their structure, possess good optical properties and are capable of molecular recognition by their supramolecular capabilities of utilizing weak forces of interaction (such as hydrogen bonding, dipole interaction) in establishing a close association with targets. They are easy to synthesize, which opened the opportunity for a wide pharmaceutical application, mostly as pharmacological scaffolds. However, challenges such as poor water solubility, inefficient drug delivery and increased toxicities due to frequent dosing of drugs are commonly faced which reduces the efficacy of the drugs. It is therefore important to have “delivery vehicles” which could help transport the drugs to …

License Plate Image Quality Enhancement Utilizing Super Resolution Generative Adversarial Networks, Mark Moelter

College of Graduate Studies: Theses & Dissertations

This thesis focuses primarily on enhancing the image quality of blurred license plates through the use of Super-Resolution Generative Adversarial Networks (SRGANs) [1]. We propose a synthetic dataset with SRGAN model to promote blurred image quality enhancement, and allow for model evaluation on a multitude of image input and output size combinations. SRGAN is mainly used for low-resolution image enhancement, but by heavily blurring the input images, the model is tested on its ability to blindly deblur and upsample images to the desired super-resolution (SR) size. The model enhances the image quality to nearly that of the reference images. The …

Synthesis And Characterization Of Multimetallic Clusters Featuring Iron, Cobalt, And 2,6-Bis(Trialkylsilylamino)Pyridines, Lynn Nguyen

College of Graduate Studies: Theses & Dissertations

Extended metal atom chain (EMAC) complexes are multimetallic complexes of three or more metals, often containing M-M bonds, with the metal ions arranged linearly. These complexes have significant potential as molecular wires. They can elicit unique physical properties and reactivities, sometimes a result of direct magnetic exchange between metal centers, especially when incorporating first row transition metals. The synthesis of the first linear, triiron (II) complex with 2,6-bis[(trimethylsilyl)amino]pyridine (H₂L^Me) featuring Fe-Fe bonding from our group, Fe₃L^Me₃, motivated the expansion of linear multimetallic EMAC complexes with Fe and Co, incorporating M-M bonds. …

Male Color Badges Advertise Multiple Messages: Tradeoffs Among Color Badge Intensity, Size, And Ectoparasite Load, Katherine M. Roberts

College of Graduate Studies: Theses & Dissertations

Condition-dependent signals can be used by conspecifics to obtain information on an individuals’ quality such as health, fighting ability, or immunocompetence. Variation in the severity of parasitic infections could mediate the differential expression of sexual signals in distinct populations of the same species. This could create diverse condition-dependent relationships between signals and quality. In this study, I examine the relationship between male signal expression and quality of Sceloporus woodi that inhabit areas with distinct ectoparasitic pressures. First, I examined if the brightness or size of male signals is indicative of body size or body condition in males without ectoparasites. Second, …

Neosublime, Reframing The Philosophical, Kathy Varadi

College of Graduate Studies: Theses & Dissertations

Why have the sunsets and sunrises become so amazingly colorful and awe inspiring recently? Eighteenth century philosophers said such events were examples of the sublime. They defined the sublime as that which is the most absolutely great combined with an underlying element of fear usually caused by the actions of God. This infers that the sublime is something that you can’t fully understand or wrap your head around and leaves you speechless and spell bound. Contemporary art critics say that the sublime is no longer applicable to art because it has been overused. I disagree, and in my art, I …

Evaluation Of Tidal Fresh Forest Distributions And Tropical Storm Impacts Using Sentinel-2 Msi Imagery, Galen Costomiris

College of Graduate Studies: Theses & Dissertations

Situated in the transitional zone between non-tidal forests upstream and tidal fresh marshes downstream, tidal fresh forests occupy a unique and increasingly precarious habitat. The threat of intensifying anthropogenic climate change, compounded by the effects of historical logging and drainage alterations, could reduce the extent of this valuable ecosystem. The overall goals of this project were to identify forest communities present in the Altamaha tidal fresh forest; develop satellite imagery-based classifications of tidal fresh forest and tidal marsh vegetation along the Altamaha River, Georgia; and to quantify changes in vegetation distribution in the aftermath of hurricanes Matthew and Irma. Based …

Cloud-Based Machine Learning And Sentiment Analysis, Emmanuel C. Opara

College of Graduate Studies: Theses & Dissertations

The role of a Data Scientist is becoming increasingly ubiquitous as companies and institutions see the need to gain additional insights and information from data to make better decisions to improve the quality-of-service delivery to customers. This thesis document contains three aspects of data science projects aimed at improving tools and techniques used in analyzing and evaluating data. The first research study involved the use of a standard cybersecurity dataset and cloud-based auto-machine learning algorithms were applied to detect vulnerabilities in the network traffic data. The performance of the algorithms was measured and compared using standard evaluation metrics. The second …

Biomimetic Synthesis Of Palladium Nanoparticles For Catalytic Application, Emily A. Groover

College of Graduate Studies: Theses & Dissertations

The synthesis of palladium nanoparticles (Pd NPs) using materials-directed peptides is a novel, nontoxic approach which exerts a high level of control over the particle size and shape. This biomimetic technique is environmentally benign, featuring nonhazardous ligands and ambient conditions. Nanoparticles are extremely reactive catalysts, boasting a large surface-to-volume ratio when compared to their bulk counterparts. The rational design of these nanoparticles using peptides has been very successful in aqueous environments, but no research has been done to apply it in organic systems. As such, the biomimetic synthesis of Pd NPs in an organic system is here investigated, with ethanol …

The Application Of Deep Learning And Cloud Technologies To Data Science, Ian A. Trawinski

College of Graduate Studies: Theses & Dissertations

Machine Learning and Cloud Computing have become a staple to businesses and educational institutions over the recent years. The two forefronts of big data solutions have garnered technology giants to race for the superior implementation of both Machine Learning and Cloud Computing. The objective of this thesis is to test and utilize AWS SageMaker in three different applications: time-series forecasting with sentiment analysis, automated Machine Learning (AutoML), and finally anomaly detection. The first study covered is a sentiment-based LSTM for stock price prediction. The LSTM was created with two methods, the first being SQL Server Data Tools, and the second …