Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network

Open Access. Powered by Scholars. Published by Universities.®

Articles 31 - 60 of 200

Full-Text Articles in Entire DC Network

Ring Bose–Einstein Condensate Atomtronic Rotation Sensor, Oluwatobi I. Adeniji Jan 2022

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

Electronic Theses and 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, ΩR, 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 Jan 2022

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

Electronic Theses and 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 …


Characterization Of Functionalized Carbon Nanotubes And Polystyrene/Cnt Composites Prepared With Microwave-Induced Polymerization, Allen Hulette Jan 2022

Characterization Of Functionalized Carbon Nanotubes And Polystyrene/Cnt Composites Prepared With Microwave-Induced Polymerization, Allen Hulette

Electronic Theses and Dissertations

The use of carbon nanotubes in polymer composites can increase the mechanical properties of the resulting product. Carbon nanotubes are known to have chemical interactions that make them attracted to one another and fall out of solution. To reduce this agglomeration and disperse the mechanical properties throughout the composite, functional groups are covalently added to the carbon nanotubes. Another known property of carbon nanotubes is their ability to absorb microwaves and convert it into other forms of energy. This research investigates the effects of carbon nanotube absorption of microwaves and initiation of styrene monomer polymerization. Grignard reactions are used to …


Toward Novel Optical Functionalities Through Intelligent Photonic Structure Design, Robert J. Williamson Jan 2022

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

Electronic Theses and 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 …


The Synthesis And Biocatalytic Reduction Of Beta-Keto Alkynes, Rhema M. Francis Jan 2022

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

Electronic Theses and 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 …


License Plate Image Quality Enhancement Utilizing Super Resolution Generative Adversarial Networks, Mark Moelter Jan 2022

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

Electronic Theses and 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 …


Modelling Muscle Activation Using Emg Signal, Mercy U. Okonna Jan 2022

Modelling Muscle Activation Using Emg Signal, Mercy U. Okonna

Electronic Theses and Dissertations

(EMG) is a method for measuring muscle activity by an electrical signal, and is useful in studying motor control, postural control, and in physical therapy. A current research topic is creating an algorithm that can use the EMG signal to reliably classify a muscle as active or inactive. This thesis presents a classification algorithm for leg muscles with a single activation spike while walking. Time is rescaled into steps, which are identified using data from cameras measuring joint angles while walking. The algorithm is based on moving averages and a convex combination of mean signal strength in active and inactive …


The Application Of Deep Learning And Cloud Technologies To Data Science, Ian A. Trawinski Jan 2022

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

Electronic Theses and 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 …


Evaluation Of Tidal Fresh Forest Distributions And Tropical Storm Impacts Using Sentinel-2 Msi Imagery, Galen Costomiris Jan 2022

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

Electronic Theses and 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 …


Biomimetic Synthesis Of Palladium Nanoparticles For Catalytic Application, Emily A. Groover Jan 2022

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

Electronic Theses and 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 …


Cryptography Through The Lens Of Group Theory, Dawson M. Shores Jan 2022

Cryptography Through The Lens Of Group Theory, Dawson M. Shores

Electronic Theses and Dissertations

Cryptography has been around for many years, and mathematics has been around even longer. When the two subjects were combined, however, both the improvements and attacks on cryptography were prevalent. This paper introduces and performs a comparative analysis of two versions of the ElGamal cryptosystem, both of which use the specific field of mathematics known as group theory.


Synthesis And Characterization Of Multimetallic Clusters Featuring Iron, Cobalt, And 2,6-Bis(Trialkylsilylamino)Pyridines, Lynn Nguyen Jan 2022

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

Electronic Theses and 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 (H2LMe) featuring Fe-Fe bonding from our group, Fe3LMe3, motivated the expansion of linear multimetallic EMAC complexes with Fe and Co, incorporating M-M bonds. …


Developing And Validating A Machine Learning-Based Student Attentiveness Tracking System, Andrew L. Sanders Jan 2022

Developing And Validating A Machine Learning-Based Student Attentiveness Tracking System, Andrew L. Sanders

Electronic Theses and Dissertations

Academic instructors and institutions desire the ability to accurately and autonomously measure the attentiveness of students in the classroom. Generally, college departments use unreliable direct communication from students (i.e. emails, phone calls), distracting and Hawthorne effect-inducing observational sit-ins, and end-of-semester surveys to collect feedback regarding their courses. Each of these methods of collecting feedback is useful but does not provide automatic feedback regarding the pace and direction of lectures. Young et al. discuss that attention levels during passive classroom lectures generally drop after about ten to thirty minutes and can be restored to normal levels with regular breaks, novel activities, …


Investigation Of Intramolecular And Intermolecular Aza-Michael Reactions, Nadia Z. Singleton Jan 2022

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

Electronic Theses and 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 …


Reinforcement Learning: Low Discrepancy Action Selection For Continuous States And Actions, Jedidiah Lindborg Jan 2022

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

Electronic Theses and 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.


Molybdenum Oxide/Antimony Nanobelts Embedded In Asymmetric Membranes For Use As High-Capacity Lithium/Sodium-Ion Battery Anodes, Logan Williams Jan 2022

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

Electronic Theses and 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 …


Synthesis Of Functionalized Aromatic Heterocyclic Compounds And Its Applications In Organized Self-Assemblies, Emmanuel T. Fasusi Jan 2022

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

Electronic Theses and 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 …


Using Ai-Enabled Gaze Tracking System To Understand Comprehension Patterns Of Computer Science Students, Bradley Boswell Jan 2022

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

Electronic Theses and 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 …


Non-Inferiority Testing: Kernel Estimation And Overlap Measure, Larie C. Ward Jan 2022

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

Electronic Theses and 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 …


Hydroamidation With Acetamides And Trifluoroacetamides, Gordon H. Whitetree Jan 2021

Hydroamidation With Acetamides And Trifluoroacetamides, Gordon H. Whitetree

Electronic Theses and Dissertations

The hydroamidation reaction is an attractive methodology for the construction of larger functional molecules. In our research, a baseline reactivity was established for the hydroamidation reaction using a set of N-alkyl and N-aryl (trifluoro)acetamides with methyl acrylate and acrylonitrile, various bases and varying reaction conditions. The combination of alkenes, acetamides, and trifluoroacetamides with base was crucial for reaction rate. N-aryl trifluoroacetamides exhibited near quantitative conversions in neat alkene with Diazabicycloundecene (DBU) as base. The less acidic N-aryl acetamides performed much faster in the presence of KOtBu and conversions of >95% were accomplished regularly but contained a large presence …


Arnold Transformations As Applied To Data Encryption, Haley N. Anderson Jan 2021

Arnold Transformations As Applied To Data Encryption, Haley N. Anderson

Electronic Theses and Dissertations

As our world becomes increasingly digital, data security becomes key. Data must be encrypted such that it can be easily encrypted only by the intended recipient. Arnold Transformations are a useful tool in this because of its unpredictable periodicity. Our goal is to outline a method for choosing an Arnold Transformation that is both secure and easy to implement. We find the necessary and sufficient condition that a key matrix has periodicity. The chosen key matrix has a random structure, and it has a periodicity that is sufficiently high. We apply this method to several image and data string examples …


Design, Synthesis And Applications Of Nanoparticles In Suppression Of Mosquito-Born Flaviviridae Viruses, Maria R. Blahove Jan 2021

Design, Synthesis And Applications Of Nanoparticles In Suppression Of Mosquito-Born Flaviviridae Viruses, Maria R. Blahove

Electronic Theses and Dissertations

Recently, nanoparticles have become an origin of exploration in the chemistry field due to their unique medical uses. The current drug delivery models of nanoparticles often include a metal base with a drug conjugated to its surface. However this raises concerns regarding toxicity. A novel approach to solving this dilemma is the development of nanosized biocompatible polymer-based micelles, created from PEG-PCL-PEG triblock polymer, and formed around a drug of choice. The goal is to create a drug carrier nanoparticle system that is labile at a specific intracellular pH, without undue toxicity to the cell. This creates a drug-loaded nanoparticle that …


Implementing A Neural Network For Supervised Learning With A Random Configuration Of Layers And Nodes, Kane A. Phillips Jan 2021

Implementing A Neural Network For Supervised Learning With A Random Configuration Of Layers And Nodes, Kane A. Phillips

Electronic Theses and Dissertations

Deep learning has a substantial amount of real-life applications, making it an increasingly popular subset of artificial intelligence over the last decade. These applications come to fruition due to the tireless research and implementation of neural networks. This paper goes into detail on the implementation of supervised learning neural networks utilizing MATLAB, with the purpose being to generate a neural network based on specifications given by a user. Such specifications involve how many layers are in the network, and how many nodes are in each layer. The neural network is then trained based on known sample values of a function …


Bias Of Rank Correlation Under A Mixture Model, Russell Land Jan 2021

Bias Of Rank Correlation Under A Mixture Model, Russell Land

Electronic Theses and Dissertations

This thesis project will analyze the bias in mixture models when contaminated data is present. Specifically, we will analyze the relationship between the bias and the mixing proportion, p, for the rank correlation methods Spearman’s Rho and Kendall’s Tau. We will first look at the history of the two non-parametric rank correlation methods and the sample and population definitions will be introduced. Copulas will be introduced to show a few ways we can define these correlation methods. After that, mixture models will be defined and the main theorem will be stated and proved. As an example, we will apply this …


The Effects Of Nacl On The Triple Helix Structure Of Collagen And The Reinforcement Of Tung Oil-Based Polymers With Collagen Peptides, Christopher Dzorkpata Jan 2021

The Effects Of Nacl On The Triple Helix Structure Of Collagen And The Reinforcement Of Tung Oil-Based Polymers With Collagen Peptides, Christopher Dzorkpata

Electronic Theses and Dissertations

In this research, a collagen-reinforced bio-composite from tung oil was prepared using free radical initiation and thermal polymerization, leading to polyolefinic tung oil-based matrix. Two peptides (long and short) were synthesized and their secondary features were analyzed using circular dichroism spectroscopy. After this analysis, the long peptide exhibited more triple helix characteristics as compared to the short peptide. The full protein will ultimately have a better interaction with the tung oil, was used in the synthesis of the collagen-reinforced bio-composite. The presence of NaCl in the triple helix and its overall effect on the thermal and mechanical properties of the …


New Results On Cyclic Compositions And Multicompositions, Silvana Ramaj Jan 2021

New Results On Cyclic Compositions And Multicompositions, Silvana Ramaj

Electronic Theses and Dissertations

Integer compositions, cyclic compositions, and lately k-compositions, are an important topic in combinatorics and number theory. In this paper, we will explain, the general approach of using generating functions to study number sequences involving compositions, cyclic compositions, k-compositions, and the number of parts in each of them. After generating the data, some properties are observed and proved. Also, some interesting bijections involving Pell numbers and the Jacobsthal sequence are given.


Numerical Approximation Of Lyapunov Exponents And Its Applications In Control Systems, Nakita K. Andrews Jan 2021

Numerical Approximation Of Lyapunov Exponents And Its Applications In Control Systems, Nakita K. Andrews

Electronic Theses and Dissertations

The progression of state trajectories with respect to time, and its stability properties can be described by a system of nonlinear differential equations. However, since most nonlinear dynamical systems cannot be solved by hand, one must rely on computer simulations to observe the behavior of the system. This work focuses on chaotic systems. The Lyapunov Exponent (LE) is frequently used in the quantitative studies of a chaotic system. Lyapunov exponents give the average rate of separation of nearby orbits in phase space, which can be used to determine the state of a system, e.g. stable or unstable. The objective of …


Lstm-Based Model For Human Brain Decisions Using Eeg Signals Analysis, Lorela Bano Jan 2021

Lstm-Based Model For Human Brain Decisions Using Eeg Signals Analysis, Lorela Bano

Electronic Theses and Dissertations

As machine learning models become more sophisticated, and biometric data becomes more readily available through new non-invasive technologies, it becomes increasingly possible to gain access to interesting biometric data that could revolutionize Human Computer Interaction. In this research, we propose a framework to assess and quantify human preference (like or dislike) on presenting various external visual stimuli. Our framework relies on an Long Short-Term Memory (LSTM) Recurrent Neural Network (RNN) based model and on electroencephalogram (EEG) signals analysis to predict Like or Dislike preference of human subjects when presented with various marketing images.


The Role Of Symbiotic Algae In The Acclimatization Of Oculina Arbuscula To Ocean Acidification, Erin M. Arneson Jan 2021

The Role Of Symbiotic Algae In The Acclimatization Of Oculina Arbuscula To Ocean Acidification, Erin M. Arneson

Electronic Theses and Dissertations

Ocean acidification (OA) caused by CO2 emissions is projected to decrease seawater pH to 7.6 by 2100. Scleractinian corals are at risk because excess H+ in seawater binds to carbonate (CO32-), reducing its availability for CaCO3 skeletons. The energy demand for skeletal growth increases as pH decreases because corals must actively purge excess H+ from their seawater sourced calcifying fluid to maintain high calcification rates. In scleractinian corals it is hypothesized that photosynthesis by symbiotic algae is critical to meet this increased energy demand. To test this hypothesis, I conducted laboratory and field …


Advancements In Bio-Based Novel (Co)Monomers For Polymeric Materials, Khristal Anne Monroe Jan 2021

Advancements In Bio-Based Novel (Co)Monomers For Polymeric Materials, Khristal Anne Monroe

Electronic Theses and Dissertations

Most current research in the area of sustainable and environmentally friendly materials relate to the use of renewable sources for the fabrication of bio-based polymers and composites. Using plant-based derivatives is a common strategy. Pine sap can be distilled into turpentines (light fraction) and pine rosin (heavy fraction). Pine rosin is obtained as a brittle solid and its major component is abietic acid. This project aims at investigating a synthetic approach for the synthesis of a pine rosin-based polymer that can be potentially used for manufacturing a collection device for pine sap. The synthetic strategy consisted in the preparation of …