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Theses and Dissertations

2020

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Full-Text Articles in Physical Sciences and Mathematics

Deep Learning-Based Reconstruction Of Volumetric Ct Images Of Vertebrae From A Single View X-Ray Image, Mingren Xiang Dec 2020

Deep Learning-Based Reconstruction Of Volumetric Ct Images Of Vertebrae From A Single View X-Ray Image, Mingren Xiang

Theses and Dissertations

Computed tomography is often used in medical fields today because it creates more detailed information for doctors than regular X-ray images. However, one major side effect is that patients may be exposed to a large dose of radiation because it takes hundreds of X-ray images to compute a CT scan. Another shortcoming is that patients are required to lay down on the CT machine for the scan, which is usually not the ideal position when diagnosing spine related issues such as cervical spondylosis and lumbar disc herniation. The prime motivation for this study is to reconstruct CT images using only …


The Design And Validation Of A Discrete-Event Simulator For Carbohydrate Metabolism In Humans, Husam Ghazaleh Dec 2020

The Design And Validation Of A Discrete-Event Simulator For Carbohydrate Metabolism In Humans, Husam Ghazaleh

Theses and Dissertations

CarbMetSim is a discrete event simulator that tracks the changes of blood glucose level of a human subject after a timed series of diet and exercises activities. CarbMetSim implements wider aspects of carbohydrate metabolism in individuals to capture the average effect of various diet/exercise routines on the blood glucose level of diabetic patients. The simulator is implemented in an object-oriented paradigm, where key organs are represented as classes in the CarbMetSim. Key organs (stomach, intestine, portal vein, liver, kidney, muscles, adipose tissue, brain and heart) are implemented to the extent necessary to simulate their impact on the production and consumption …


Intelligent Therapeutic Robot: Design, Development, And Control, Asif Al Zubayer Swapnil Dec 2020

Intelligent Therapeutic Robot: Design, Development, And Control, Asif Al Zubayer Swapnil

Theses and Dissertations

This research contributes to developing an Intelligent Therapeutic Robot (iTbot) designed to provide therapy to patients with upper limb impairment due to stroke, injury, and other trauma. This robot aims to implement robotic rehabilitation based on principles of motor rehabilitation and Neuroplasticity. The iTbot, as developed in this research, can provide end-effector type rehabilitation exercises in various configurations, including motion in the vertical and horizontal plane. It can provide passive, active, and active-assisted rehabilitation therapies to patients with limited upper limb mobility.

The iTbot has been designed with simplicity in mind with a minimum viability approach. With a minimum amount …


Proactive Management In Academic Libraries: Promoting Improved Communication And Inclusion Of Academic Librarians And Archivists In Cybersecurity Policy Creation, Paul J. Luft Dec 2020

Proactive Management In Academic Libraries: Promoting Improved Communication And Inclusion Of Academic Librarians And Archivists In Cybersecurity Policy Creation, Paul J. Luft

Theses and Dissertations

Although increasing cybersecurity threats continue in libraries, not many studies are available which examine surrounding cybersecurity policies. Even less has been done on specific types of libraries such as academic and archives. When it comes to academic libraries, cybersecurity policies take a top-down approach to managing and creating policies. The problem is that both academic libraries and archives are unique areas within a university setting. Some of the general policies do not always handle specific issues dealt with in an academic library or archives. This paper investigates if an actual gap or void in policy exists which could create issues …


Characterization Of Fiber Bragg Grating Based, Geometry-Dependent, Magnetostrictive Composite Sensors, Edward Lynch Dec 2020

Characterization Of Fiber Bragg Grating Based, Geometry-Dependent, Magnetostrictive Composite Sensors, Edward Lynch

Theses and Dissertations

Optical sensors based on geometry dependent magnetostrictive composite, having potential applications in current sensing and magnetic field sensing are modeled and evaluated experimentally with an emphasis on their thermal immunity from thermal disturbances. Two sensor geometries composed of a fiber Bragg grating (FBG) embedded in a shaped Terfenol-D/epoxy composite material, which were previously prototyped and tested for magnetic field response, were investigated. When sensing magnetic fields or currents, the primary function of the magnetostrictive composite geometry is to modulate the magnetic flux such that a magnetostrictive strain gradient is induced on the embedded FBG. Simulations and thermal experiments reveal the …


Sedimentology, Sequence Stratigraphy, And High-Precision U-Pb Age Constraints On The Late Paleozoic Ansilta Formation, Calingasta-Uspallata Basin, Nw Argentina, John Ethan Malone Dec 2020

Sedimentology, Sequence Stratigraphy, And High-Precision U-Pb Age Constraints On The Late Paleozoic Ansilta Formation, Calingasta-Uspallata Basin, Nw Argentina, John Ethan Malone

Theses and Dissertations

The Ansilta Formation, located several kilometers east of the Astronomical Observatory El Leoncito near Barreal, San Juan Province, Argentina was deposited during the late Mississippian to early Pennsylvanian. This succession includes glacimarine, nearshore, and fluvial systems deposited at the mid-Carboniferous portion of the late Paleozoic ice age within the Calingasta—Uspallata Basin on the western margin of the Protoprecordillera. The lower member of the Ansilta Formation is equivalent to the nearby Leoncito, Majaditas, and Hoyada Verde formations, and is composed of diamictite, conglomerates, sandstones, pebbly mudstones, and laminated mudstone. Glacial environments are unique in that facies changes occur as a result …


A Mechanistic Investigation Of Cytochrome C Nitrite Reductase Catalyzed Reduction Of Nitrite To Ammonia: The Search For Catalytic Intermediates, Shahid Shahid Dec 2020

A Mechanistic Investigation Of Cytochrome C Nitrite Reductase Catalyzed Reduction Of Nitrite To Ammonia: The Search For Catalytic Intermediates, Shahid Shahid

Theses and Dissertations

Cytochrome c Nitrite Reductase (ccNiR) is a periplasmic homodimeric decaheme enzyme that catalyzes the reduction of nitrite to ammonium in a process that involves six electrons and eight protons. Under standard assay conditions, which use a strong reducing agent as an electron source, catalysis takes place rapidly without producing detectable intermediates. However, intermediates do accumulate when weaker reducing agents are employed, allowing the ccNiR mechanism to be studied. Herein, the early stages of Shewanella oneidensis ccNiR-catalyzed nitrite reduction were investigated in isolation by using the weak reducing agents N,N,N’,N’-tetramethyl-p-phenylenediamine (TMPD) and the 2-electron reduced form of indigo trisulfonate. Experiments were …


Asymptotic Expansion Of The L^2 Norms Of The Solutions To The Heat And Dissipative Wave Equations On The Heisenberg Group, Preston Walker Dec 2020

Asymptotic Expansion Of The L^2 Norms Of The Solutions To The Heat And Dissipative Wave Equations On The Heisenberg Group, Preston Walker

Theses and Dissertations

Motivated by the recent work on asymptotic expansions of heat and dissipative wave equations on the Euclidean space, and the resurgent interests in Heisenberg groups, this dissertation is devoted to the asymptotic expansions of heat and dissipative wave equations on Heisenberg groups. The Heisenberg group, $\mathbb{H}^{n}$, is the $\mathbb{R}^{2n+1}$ manifold endowed with the law $$(x,y,s)\cdot (x',y',s') = (x+x', y+y', s+ s' + \frac{1}{2} (xy' - x'y)),$$ where $x,y\in \mathbb{R}^{n}$ and $t\in \mathbb{R}$. Let $v(t,z)$ and $u(t,z)$ be solutions of the heat equation, $v_{t} - \mathcal{L} v=0$, and dissipative wave equation, $u_{tt}+u_{t} - \mathcal{L}u =0$, over the Heisenberg group respectively, where …


Macromolecular Structure Determination At X-Ray Free Electron Lasers From Single-Particle Imaging To Time-Resolved X-Ray Crystallography, Ishwor Poudyal Dec 2020

Macromolecular Structure Determination At X-Ray Free Electron Lasers From Single-Particle Imaging To Time-Resolved X-Ray Crystallography, Ishwor Poudyal

Theses and Dissertations

X-ray free-electron lasers (XFELs) open the possibility of obtaining diffraction information from a single biological macromolecule. This is because XFELs can generate extremely intense X-ray pulses which are so short that diffraction data can be collected before the sample is destroyed. By collecting a sufficient number of single-particle diffraction patterns from many tilts of a molecule relative to the X-ray beam, the three-dimensional electron density can be reconstructed ab-initio. The resolution and therefore the information content of the data will ultimately depend largely on the number of patterns collected at the experiment. We estimate the number of diffraction patterns required …


Novel Approaches To The Determination Of Toxic Metals In Industrial Waste And Soil Extracts, Garrett Bruce Finn Dec 2020

Novel Approaches To The Determination Of Toxic Metals In Industrial Waste And Soil Extracts, Garrett Bruce Finn

Theses and Dissertations

Abstract:Because of their environmental impact, the contamination and migration of heavy metals is an important field of study. In this thesis, two novel methods for measuring toxic metals over a broad concentration range in complex matrices were successfully developed and applied to authentic samples. This research focused on toxic metals in two disparate environments: industrial effluent and soil. The primary work reported in this research focused on developing a Sequential Injection Analysis (SIA) process monitor to measure metals in industrial process waste streams in near real-time. Molecular Absorption Spectroscopy was used to determine levels of Zn and several other metals. …


Effects Of Intercalation And Deintercalation In Layered Materials: From Topological Insulators To Battery Cathodes, Uma Garg Dec 2020

Effects Of Intercalation And Deintercalation In Layered Materials: From Topological Insulators To Battery Cathodes, Uma Garg

Theses and Dissertations

Topological insulators are quantum materials which have insulating bulk and conducting surface. The surface states in these materials is protected by time reversal symmetry and spin-orbit coupling. The fascinating quantum properties of these materials could lead to high speed electronics and quantum computing. To explore the transport properties of these systems, I synthesized single crystals of SnTe and Sb2Se3 which are potential topological insulators. SnTe is a topological crystalline insulator in which topological surface states are protected by time reversal symmetry and crystal symmetry, in particular mirror symmetry. My Shubnikov-de Haas (SdH) oscillation study on the (001) surface of SnTe …


Lattice And Charge Order In Layered Bi-Based Topological Insulators, Yanan Li Dec 2020

Lattice And Charge Order In Layered Bi-Based Topological Insulators, Yanan Li

Theses and Dissertations

Bi2X3 (X=Se/Te) is a topological insulator, as well as a layered dichalcogenide. The topological properties of Bi2Se3 have gained a lot of interest over the past decade. However, as a layered chalcogenide, much of its uniqueness has not been fully discovered, e.g. hosting Charge Density Wave as reported in most other chalcogenides. With intercalation of Nb, Cu and Sr, Bi2Se3 becomes an unconventional superconductor. Together with its topological properties, A-Bi2X3 (A=Nb, Cu and Sr) have been proposed to be potential Topological superconductors. However, the mechanism of the unconventional SC in these compounds is still under discussion.

For my PhD research, …


Empowering People With Cognitive Disabilities To Live Independently By Supporting Their Self-Management Of Food And Related Expenses, Apoorv Prasad Dec 2020

Empowering People With Cognitive Disabilities To Live Independently By Supporting Their Self-Management Of Food And Related Expenses, Apoorv Prasad

Theses and Dissertations

People with ADHD (attention deficit hyperactivity disorder) often have difficulty in planning and organization that can impact their eating habits and lifestyle. We have created a novel mobile software application to support choosing meals and making healthy food purchases that meet dietary preferences within a specified budget. The core functions allow 1) Managing user profiles to support personalization 2) Obtaining recipe recommendations to fit profile, budget, and foods-on-hand 3) Planning food purchases, and 4) Reviewing foods-on-hand, budget and the nutritional balance of recent meals and food purchases.The application supports self-introspection to help people with ADHD review their history of food …


Trace: A Differentiable Approach To Line-Level Stroke Recovery For Offline Handwritten Text, Taylor Neil Archibald Dec 2020

Trace: A Differentiable Approach To Line-Level Stroke Recovery For Offline Handwritten Text, Taylor Neil Archibald

Theses and Dissertations

Stroke order and velocity are helpful features in the fields of signature verification, handwriting recognition, and handwriting synthesis. Recovering these features from offline handwritten text is a challenging and well-studied problem. We propose a new model called TRACE (Trajectory Recovery by an Adaptively-trained Convolutional Encoder). TRACE is a differentiable approach using a convolutional recurrent neural network (CRNN) to infer temporal stroke information from long lines of offline handwritten text with many characters. TRACE is perhaps the first system to be trained end-to-end on entire lines of text of arbitrary width and does not require the use of dynamic exemplars. Moreover, …


A Machine Learning Approach To Forecasting Sep Events With Solar Activities, Jesse Scott Torres Dec 2020

A Machine Learning Approach To Forecasting Sep Events With Solar Activities, Jesse Scott Torres

Theses and Dissertations

Solar energetic particles (SEPs) are fast-moving events which can cause severe damage to astronauts and their equipment, and can disrupt communications on Earth. There are no clear patterns in solar activities which indicate whether an SEP is about to occur, making physics-based methods inaccurate for SEP forecasting. Therefore, in order to provide an advance warning so that astronauts are able to get to safety, we apply neural networks to the problems of forecasting SEP occurrence and intensity. Our algorithm for predicting SEP occurrence uses a combination of observed CME properties and derived features and achieves a TSS of 0.846 and …


A Fast And Exact Motif Enumeration Algorithm For Dynamic Networks, Abbas Al-Thaedan Dec 2020

A Fast And Exact Motif Enumeration Algorithm For Dynamic Networks, Abbas Al-Thaedan

Theses and Dissertations

From social to biological networks, prior research in complex networks have demonstrated the importance of the frequency and distribution of different types of motifs to important network functions and properties. A network motif (or graphlet) is defined as a small connected sub-pattern which is over-represented in a network. Network motifs have been widely applied in a wide range of applications, namely biological, social, and technical networks. The counting of the network motif involves expensive enumeration of graph sub-patterns along with the detection of graph isomorphism. In general, network motif detection algorithms are computationally expensive and often designed to operate over …


Real-Time Full Face Closed Eyes Detection, Lucas De Morais Tramasso Dec 2020

Real-Time Full Face Closed Eyes Detection, Lucas De Morais Tramasso

Theses and Dissertations

Intelligent systems based on machine-learning techniques are becoming a common way of solving problems in many different areas. In this thesis, our goal is to apply machine learning to a computer vision problem. We propose a new solution to detect closed eyes in full-face images. Accurate detection of closed eyes can be used in many problems such as driver drowsiness detection, human-computer interaction, and computer user monitoring. Most algorithms used to detect blinks or closed eyes follow a similar workflow. They require detection of a region of interest that is then used with different algorithms and techniques to determine if …


Optimization Framework For Reconstructing Biomedical Images By Efficient Sample-Based Parameterization, Paul Richard Arbic Ii Dec 2020

Optimization Framework For Reconstructing Biomedical Images By Efficient Sample-Based Parameterization, Paul Richard Arbic Ii

Theses and Dissertations

An efficient computational approach for optimal reconstruction of binary-type images suitable for models in various biomedical applications is developed and validated. The methodology includes derivative-free optimization supported by a set of sample solutions with customized geometry generated synthetically. The entire framework has an easy to follow design due to a nominal number of tuning parameters which makes the approach simple for practical implementation in various settings, adjusting it to new models, and enhancing the performance. High efficiency in computational time is achieved through applying the coordinate descent method to work with individual controls in the predefined custom order. This technique …


Refinements Of The Concept Of Privacy In Distributed Computing, Entisar Seedi Alshammry Dec 2020

Refinements Of The Concept Of Privacy In Distributed Computing, Entisar Seedi Alshammry

Theses and Dissertations

In light of the tremendous development of technology in the modern world in which we live, privacy concerns are increasing, especially after the massive spread of distributed computing systems and the technologies that depend on it, whether in personal devices or public services. Hence, this research proposes refinements on the concept of privacy for enhancing the development of privacy-related strategies in distributed computing systems to address the elements of privacy. In particular, the study introduces the new concept of Privacy Appetite to describe and model the nature of the relationship between the intended disclosure of private information and gained value …


Real-Time Action Classification Using Intermediate Skeletal Pose Estimation, Kleanthis Zisis Tegos Dec 2020

Real-Time Action Classification Using Intermediate Skeletal Pose Estimation, Kleanthis Zisis Tegos

Theses and Dissertations

The topic of Human Action Classification has attracted significant interest these past years, which can be attributed to the advancements in deep learning methodologies. Its applications range from robotics to surveillance and automated video categorization, as well as in the healthcare industry. The literature, however, has primarily focused on offline action classification, without significant attention being given to the constraints of an online real-time classifier. Using an intermediate skeletal representation of humans, while convoluted, provides a scalable means of tackling the action classification problem. This project discusses the existing literature, and adapts two of the state-of-the-art approaches for real-time analysis. …


Biometric Face Skintone Data Augmentation Using A Generative Adversarial Network, Rosalin Dash Dec 2020

Biometric Face Skintone Data Augmentation Using A Generative Adversarial Network, Rosalin Dash

Theses and Dissertations

Researchers seek methods to increase the accuracy and efficiency in identifying an individual using facial biometric systems. Factors like skin color, which may affect the accuracy of facial recognition, need to be investigated further. To analyze the impact of race with respect to skin color of face on biometric systems, we focused on generating a dataset with uniformly distributed images of different skin tones while preserving identities. Deep learning neural network architectures like the generative adversarial network (GAN) focus on modifying only certain features of the face like the color of the skin. In our experimental approach, we implemented a …


Deep Learning-Based, Passive Fault Tolerant Control Facilitated By A Taxonomy Of Cyber-Attack Effects, Dean C. Wardell Dec 2020

Deep Learning-Based, Passive Fault Tolerant Control Facilitated By A Taxonomy Of Cyber-Attack Effects, Dean C. Wardell

Theses and Dissertations

In the interest of improving the resilience of cyber-physical control systems to better operate in the presence of various cyber-attacks and/or faults, this dissertation presents a novel controller design based on deep-learning networks. This research lays out a controller design that does not rely on fault or cyber-attack detection. Being passive, the controller’s routine operating process is to take in data from the various components of the physical system, holistically assess the state of the physical system using deep-learning networks and decide the subsequent round of commands from the controller. This use of deep-learning methods in passive fault tolerant control …


Spectroscopic Diagnostics For Supersonic Air Microwave Discharges, James E. Caplinger Dec 2020

Spectroscopic Diagnostics For Supersonic Air Microwave Discharges, James E. Caplinger

Theses and Dissertations

Optical Emission Spectroscopy (OES) is an increasingly relevant technique in plasma diagnostics due to its inherent non-invasive nature and simple application relative to other popular techniques. In this work, common OES techniques are combined with novel methods, developed here, in an effort to provide comprehensive OES techniques for stationary and supersonic air microwave discharges. To this end, a detailed collisional-radiative model for strong atomic oxygen lines has been developed and used to identify the importance of often overlooked mechanisms including cascade emission and metastable excitation. Using these results, a combined argon actinometry technique was developed which makes use of the …


Electro-Optic Satellite Constellation Design Using Multi-Objective Genetic Algorithm, Yasin Tamer Dec 2020

Electro-Optic Satellite Constellation Design Using Multi-Objective Genetic Algorithm, Yasin Tamer

Theses and Dissertations

Satellite constellation design is a complex, highly constrained, and multidisciplinary problem. Unless optimization tools are used, tradeoffs must be conducted at the subsystem level resulting in feasible, but not necessarily optimal, system designs. As satellite technology advances, new methods to optimize the system objectives are developed. This study is based on the development of a representative regional remote sensing constellation design. This thesis analyses the design process of an electrooptic satellite constellation with regional coverage considerations using system-level optimization tools. A multi objective genetic algorithm method is used to optimize the constellation design by utilizing MATLAB and STK integration. Cost, …


Polymer-Based Capacitive Gas Sensor For Machine Olfaction, Mohamed Fathy Hassan Dec 2020

Polymer-Based Capacitive Gas Sensor For Machine Olfaction, Mohamed Fathy Hassan

Theses and Dissertations

Transferring human abilities and knowledge to machines has been the focus of decades of work by scientists and engineers. With the progress in computation power and algorithms such as artificial neural networks, machines have surpassed humans in complicated games like chess and the Chinese game Go. Some senses can be mimicked including touch, with pressure sensors, hearing, with microphones, and vision with charged couple device (CCD)imaging chips. Yet, relatively little progress has been made with the senses of smell and taste. Machine olfaction, the ability to detect and quantify vapors in the environment, poses a range of challenges, which if …


In-Depth Analysis Of College Students’ Data Privacy Awareness, Vernon D. Andrews Dec 2020

In-Depth Analysis Of College Students’ Data Privacy Awareness, Vernon D. Andrews

Theses and Dissertations

While attending university, college students need to be aware of issues related to data privacy. Regardless of the age, gender, race, or education level of college students, every student can relate to the advancement of the internet within the last decades. The internet has completely transformed the way the world receives and stores messages. Positively, the internet allows messages to be sent across the globe within the fraction of a second and provides students with access to potentially unlimited information on a variety of subjects. On the downside, there are issues on the internet that can cause more harm than …


Total Synthesis Of Cytotoxic Mansouramycins From Amino Acids, Beatriz Gamez Dec 2020

Total Synthesis Of Cytotoxic Mansouramycins From Amino Acids, Beatriz Gamez

Theses and Dissertations

Natural products produced by plants, animals, and microorganisms are of significant importance in chemistry for being major sources of molecular scaffolds essential for new drug discovery. Mansouramycins are cytotoxic bioactive compounds containing isoquinoline skeletons with substituents on the quinone and pyridine rings that may be difficult to synthesize. Synthetic processes exist for compounds B and D, however, there exists an absence of simple synthetic approaches to all four alkaloids.

This project aims to provide a general total synthetic pathway to Mansouramycins A—D from amino acids for possible use in cancer treatment via these isoquinolinequinones. Preliminary experimentation suggests there may be …


The Dmap-Catalyzed Acylation Of Alcohol -- A Mechanistic Study, Tania Veronica Alvarez Castro Dec 2020

The Dmap-Catalyzed Acylation Of Alcohol -- A Mechanistic Study, Tania Veronica Alvarez Castro

Theses and Dissertations

The mechanistic studies of Acylation of Alcohols catalyzed by 4-(N,N- Dimethyl-amino)-pyridine (DMAP) has been heavily studied in the literature. This reaction has attracted considerable interest from the synthetic and mechanistic points of view in recent years. In this research, the acylation of alcohols is prepared from cyclohexanol and acetic anhydride that is catalyzed by DMAP using triethyl amine (NEt3) as the auxiliary base and dichloromethane (DCM) as solvent. The reaction and final product will be analyzed by using gas chromatography (GC) and reaction progress kinetic analysis (RPKA). The mechanistic insights obtained in the present study should be useful for understanding …


Chemical Investigation Of Avocado (Persea Americana) Seed Husk (Testa): A Waste Of Waste, Orlando A. Castillo Scheren Dec 2020

Chemical Investigation Of Avocado (Persea Americana) Seed Husk (Testa): A Waste Of Waste, Orlando A. Castillo Scheren

Theses and Dissertations

Food chemistry is a new field in the world and is currently still expanding into the types of market in which it can be tapped into. There are about 1.3 billion tons of food waste produced in 2016 in the world, and food chemistry is going to help get rid of that waste by finding new and exciting applications to the things currently considered as waste. In these products, there might be new and undiscovered drugs that can be used in the market to help treat diseases for which might not have a cure at the current moment. The avocado …


Developing A Uhf/Vhf Phased-Array Satellite Ground Station, Brent K. Cole Dec 2020

Developing A Uhf/Vhf Phased-Array Satellite Ground Station, Brent K. Cole

Theses and Dissertations

Earth-satellite communications and tracking of spacecraft are accomplished using ground stations. Traditionally, this has been achieved by using a large parabolic antenna or pair of antennas that point at a source of interest and mechanically steer the antenna(s) as the source moves throughout the sky. Phased arrays, which have often been used in radio astronomy, can provide multiple benefits when used as a ground station including fast scanning speeds across the sky, tracking and communication of multiple sources simultaneously, and significant improvements to overall gain, signal-to-noise ratio (SNR), and data bandwidth. This thesis presents a preliminary analysis of a 20-element …