Engineering Commons^™

Neural Network Supervised And Reinforcement Learning For Neurological, Diagnostic, And Modeling Problems, Donald Wunsch Iii

Masters Theses

“As the medical world becomes increasingly intertwined with the tech sphere, machine learning on medical datasets and mathematical models becomes an attractive application. This research looks at the predictive capabilities of neural networks and other machine learning algorithms, and assesses the validity of several feature selection strategies to reduce the negative effects of high dataset dimensionality. Our results indicate that several feature selection methods can maintain high validation and test accuracy on classification tasks, with neural networks performing best, for both single class and multi-class classification applications. This research also evaluates a proof-of-concept application of a deep-Q-learning network (DQN) to …

Source Reconstruction In Near Field Scanning For Rfi Application, Hosseien Rezaei

Doctoral Dissertations

"This research is divided into three major topics. The first topic, mechanical magnetic field generator for communication in the ULF range, is discussed in the first paper. The second topic, source reconstruction in near field scanning for RFI application, is discussed over the course of two papers. The third topic, analysis of imbalanced 2 or 3 Wire VHF LISN, is discussed in the last two papers.

In the first topic, the possibility to use a mechanical system (a rotating magnet) as a source (generator or antenna combined) of the ULF magnetic field is investigated. Ultralow frequency (ULF) communication systems have …

Experimental And Numerical Studies Of Novel Thermal Energy Storage Materials For Applications In Concrete And Energy Storage Systems, Wenyu Liao

Doctoral Dissertations

In this work, several types of novel thermal energy storage (TES) materials and composites are explored, and a series of numerical simulation models and experimental protocols are developed to evaluate the potentials of these materials to be applied in concrete, pavement, and thermal energy storage systems.

The first two types of novel TES materials/composites are at the micro-scale, which use micro diatomite (DE) and cenosphere (Ceno) as carriers of phase change material (PCM), respectively. The third type of novel TES material is at the macro-scale, utilizing lightweight sand (LWS) and lightweight coarse aggregate as carriers to load PCM. The last …

Method Of Optimal Battery Scheduling With Optimal Battery And Photovoltaic Sizing, Gideon Hallman

Masters Theses

“Renewable energy generation is on the rise. One of the best ways to capitalize on this intermittent power supply is by using the renewable energy source in tandem with batteries. A joint photovoltaic (PV) and battery system model was created that implemented battery degradation and optimized battery usage using a Markov Decision Process (MDP). This system was then subjected to a series of tests to do a sensitivity analysis while optimizing the battery and PV sizing for the system at hand. Parametric sweeps of solar power and battery capital costs, the cost of energy taken from the grid, the cost …

Catalytic Carbon Dioxide Hydrogenation To Methanol/Dimethyl Ether Over Copper-Based Catalysts, Xiao Fan

Doctoral Dissertations

Direct synthesis of dimethyl ether (DME) via CO₂ hydrogenation has received great attention, owing to the global warming caused by CO₂ emission and increasing energy demand worldwide. In this works, three major aspects of bifunctional catalysts development were studied: (1) investigation of the roles of interaction in the CuO-ZnO-ZrO₂-Al₂O₃/HZSM-5 bifunctional catalysts, (2) deactivation and regeneration of CuO-ZnO-ZrO₂-Al₂O₃ with different zeolitic catalysts for one-step CO₂ hydrogenation to dimethyl ether, and (3) study on the enhancement of activity and stability of CZZA/HZSM-5 bifunctional catalysts via the introduction of …

The Implementation Of Energy Sharing Using A System Of Systems Approach, Julia Morgan

Doctoral Dissertations

"There is an increasing demand for renewable energy and consumers need more procurement options to meet their needs. Energy sharing provides a peer-to-peer (P2P) marketplace where prosumer electricity is redistributed to fellow energy-sharing community participants. This redistribution of prosumer electricity provides consumers with additional electricity suppliers, while also decreasing the load on the utility company. Though significant progress has been made regarding research and implementation of energy sharing, there is still room for growth when evaluating energy-sharing communities and defining appropriate community coordination based on end-user needs. The first contribution in this work identified nine characteristics of energy-sharing communities as …

Quantum Inspired Concepts In Decision Making, Qizi Zhang

Doctoral Dissertations

"In this study, several new applications of quantum-inspired techniques are presented to advance the state of the art in decision making. In the first part, a quantum boost scheme for multiple-model filters based on extended Grover’s algorithm is presented for fault detection and parameter estimation. The quantum boost scheme accelerates the convergence of the posterior probabilities in the multiple-model filter. Stability proofs for the quantum boost scheme is presented and its performance is analyzed using benchmark examples. In the second part, the scope of application is extended to modeling human decision making. The open quantum system cognition model is applied …

Investigation Of Anomalous Data Trends During Coal Dust Explosibilty Testing, Jacob Lee Miller

Doctoral Dissertations

Coal dust explosibility is a health and safety concern that has been a recognized hazard for over 100 years. Initial testing by the Author using a Siwek 20L apparatus recorded a secondary maximum pressure at higher dust concentrations (1,000-7,000g/m³) with Pulverized Pittsburgh Coal (PCC). Higher dust concentrations are beyond the typical ASTM E1226 testing procedure but are possible in mining and processing scenarios. No reference documents have been discovered that show a secondary maximum pressure at higher dust concentrations. Literature reviewed identified that once a coal dust concertation generates a peak pressure, the pressure remains constant or decreases …

Modeling For Off-Chip High-Speed Designs, Siqi Bai

Doctoral Dissertations

”Signal integrity (SI) and power integrity (PI) are essential for datacenter application. A typical datacenter rack consists of a switch on the top of the rack, servers, and storage units. Three SI/PI related problems for datacenter application are analyzed in this research.

The first topic is analysis on power via induced Quasi-quarter-wavelength resonance to reduce crosstalk. Using an analytical model and 3D full-wave simulation models, a physical explanation for the unexpected resonance in the differential signal pairs is proposed. Considering the difficulty in changing the pin map of the IC-package, several PCB layouts to eliminate the power via induced quasi-quarter-wavelength …

A Physics-Based Pi Pre-Layout Tool For Pcb Pdn Design, Shuang Liang

Masters Theses

"With increasingly stringent requirements for lower voltage supply, and higher density in PCB PDN design, now integrity (PI) is an increasingly important aspect that must be considered. A pre-layout tool based on the Cavity Model and Boundary Element Method is built to automatically achieve a specified target impedance for a multi-layered Printed Circuit Board (PCB) Power Distribution Network (PDN) design with a minimal number of decoupling capacitors.

The pre-work about the post-layout design and analysis is proposed and the guidelines for creating a decoupling capacitors network with better performance has been built. With limit inputs, physical limitations for the minimal …

Development Of Complex Lattice Cell In Benchmark Model Of Particle Bed Critical System, Elijah Chamberlain Lutz

Masters Theses

“Criticality safety benchmark evaluations require the creation of models that most accurately represent the experiment being evaluated. In some cases this can be relatively trivial with experiments containing rather simple or standard geometry. In others, such as packed bed systems, this becomes unique and a more difficult process. The importance of accurate modeling of packed bed systems for the use of criticality safety benchmark evaluations was looked at. Four models were created of various complexities and accuracy. First the multi-particle bed, consisting of a fuel particle (UC_1.7 kernel with C shell) and two filler particles (Zircaloy-4 and C + …

Design And Evaluation Of The 3d Printed Electromagnetic Absorber Built With Conductive Carbon-Filled Filament, Rui Mi

Masters Theses

"This research presents an application of the resistive frequency selective surface (FSS) fabricated with a 3D printed conductive material as an electromagnetic absorber for the EMI-reducing door. This solution allows to reduce radiated emissions of a router system. The resistive frequency selective surface has a three-layer structure. The top layer is a 3D printed FSS pattern, the middle layer is an air gap, and the bottom layer is a metal plane.

The first paper presents the methodology for manufacturing a frequency selective surface using the 3D printing technology, including the material characterization, design, fabrication, and evaluation.

The unpublished content presents …

Investigation Of Packed Bed And Moving Bed Reactors With Benchmarking Using Advanced Measurement And Computational Techniques, Binbin Qi

Doctoral Dissertations

"Trickle bed reactors (TBR), as typical packed bed reactors (PBR), are widely used in various fields. Very limited information regarding the flow behaviors, hydrodynamic, and mathematical models in extrudate catalyst shapes, such as cylinders, trilobes, and quadrilobes, can be found in literatures because the major focus was on spherical shape. Therefore, a hybrid pressure drops and liquid holdup phenomenological model for extrudate catalyst shapes was developed based on two-phase volume averaged equations, which showed high accuracy against experimental data. The maldistribution and dynamic liquid holdup were investigated in quadrilobe catalyst using gamma-ray computed tomography. A pseudo-3D empirical model was developed …

Assessment Of Rib Failure Mechanisms Using Discontinuum Mechanics Based Modeling Approach, Maurice Nuonituo Sunkpal

Doctoral Dissertations

"Coal mine rib failures are major safety and health challenge for coal mines worldwide. The need for clear procedures to evaluate mine rib behavior and to provide an efficient, reliable, and consistent rib control protocol is needed. Understanding coal rib geomechanics is essential for improving rib stability and eliminating fatality and injury trends due to rib failures. This knowledge is also vital to determine support requirements.

The rib control practices used in the 21st Century in most countries originated in roof control techniques. Understandably, applying roof control methods to coal rib does not yield desirable results. The geology of structures …

Axial Performance Of Self-Consolidating Concrete-Filled Fiber Tubes, Joshua David Carter

Masters Theses

"Concrete filled fiber tubes can be used to increase ductility and strength of a concrete member and self-consolidating concrete is an ideal material to use in practical applications of concrete-filled fiber tubular columns. However, the propensity of self-consolidating concrete to autogenous shrinkage could reduce the effectiveness of the concrete confinement. This research investigates the use of self-consolidating concrete in pre-cast FRP tubes and various methods of shrinkage reduction and compensation to increase the axial performance of said self-consolidating concrete-filled fiber tubes. Axial compression tests were performed under monotonic and cyclic conditions to determine the stress-strain relationship of the self-consolidating concrete …

Effect Of Radiation Damage On Organic Phase Change Materials Thermal Storage Properties, Ryan Phillip Steere

Doctoral Dissertations

"This work discusses the effects of radiation damage on organic phase change materials for use in nuclear reactor containments and space craft. The effects of radiation on the latent heat of polyethylene wax (PEW) and a eutectic of methyl palmitate and lauric acid (EMPaLA) are evaluated. These PCMs were irradiated in three locations: the Missouri University of Science and Technology research reactor (MSTR), the University of Missouri research reactor (MURR) and cyclotron (MUC) up to a total dose of 2826, 2895 and 662 Gy, respectively. The samples irradiated at the MSTR showed latent heat changes up to 15.5% lower than …

Identification Of Neuromarkers Using Structural And Functional Neuroimaging, Sreevalsan Sanathanan Menon

Doctoral Dissertations

"One of the grand challenges in science is understanding the human brain. Recent advances in magnetic resonance imaging have opened unmatched opportunities to demystify neural circuitry. In this research, the spatially and temporally complex neuroimaging data were used to identify neuromarkers that aids in quantifying a brain’s health. In the first part, a comparison of static and dynamic functional connectivities was made to study their efficacies in identifying intrinsic individual connectivity patterns. Results show that the intrinsic individual connectivity pattern can be used as a ‘fingerprint’ to distinguish among and identify subjects and their biological sex and is more accurately …

Analysis And Design Of Dc-Link Capacitor In Cascaded H-Bridge Multilevel Active Front-End Converter, Muhammad Shehroz Malik

Masters Theses

Medium-voltage grid-tied systems often use a cascaded H-bridge multi-level active front-end. In this converter, dc link bus capacitors play an important role in stabilizing the converter and enabling both active and reactive power injections. The present work provides analytical expressions for the capacitor current, which are essential for optimizing system design (especially capacitor size vs. lifetime). Then, the expression is incorporated into the grid connected bidirectional power system model. Consequently, this work contributes to the guiding principles to choose accurate dc link capacitor ratings against grid-side power delivery requirements.

DC-link capacitors come with an expiration date which is dependent on …

In Vitro And In Vivo Response To A Novel Borophosphate Bioactive Glass, Nada Abokefa

Masters Theses

"Bioactive glasses have been widely used in several biomedical and tissue engineering applications since the late 1960s. Numerous families of bioactive glasses have emerged over the years, with each having its own advantage and disadvantage. One concern common to all families is that most bioactive glasses create a basic or acidic environment when degraded and, therefore, are toxic for cells. Recently, there has been an increased interest in borophosphate bioactive glass (BPBGs) because of their neutral pH, release of therapeutic ions, and biodegradable properties. Despite the growing interest, there is little reported on the bioactivity of BPBGs. The biological effects …

Power Generation From Waste Heat During Oil Production, Subrahmanya Chandra Bhamidipati

Masters Theses

"The increase in the world population is causing a significant increase in the global demand for energy. This rise in demand is generally met with the use of fossil fuels. But there is considerable pressure to lessen the release of carbon through the combustion of fossil fuels. One way that the oil and gas industry can provide increased energy without carbon combustion is by extracting the latent heat energy contained in produced oil, gas and water from producing reservoirs, and from water which is cycled through depleted, end-of-life or abandoned reservoirs. Extracting this energy and using it to provide direct …

The Field Coupling Mechanism Study For Near Field Probe, Shun Liu

Masters Theses

"In this part, the radius of the loop is used to predict the voltage induced by the E- field in the circular loop antenna. The thin rectangle loop and thick rectangle loop have been investigated. The equivalent radius of the rectangle loop is estimated by the average of the one over the distance between the points on the loop to the center of the loop. The estimation matches with the numerical simulation"--Abstract, page iv.

A Simple Background Elimination Method For Miniaturized Fiber-Optic Raman Probe, Bohong Zhang

Masters Theses

"Raman scattering is called a photonic - molecular interaction based on the kinetic model of the analytic. Due to the uniqueness of the Raman scattering technique, it can provide a unique fingerprint signal for molecular recognition. However, a serious challenge often encountered in Raman measurement comes from the requirements of fast, real-time remote sensing, background fluorescence suppression, and micro-environmental detection.

A new Miniaturized Fiber-Optic Raman Probe (MFORP) for Raman spectroscopy, used especially for eliminating background fluorescence and enhancing sampling, is presented. Its main purpose is to provide an overview of excellent research on the detection of very small substances and …

The Role Of Psychological Reactance In Smart Home Energy Management Systems, Matthew Thomas Heatherly

Masters Theses

“With an ever-growing demand for energy, our increasing consumption is producing more greenhouse gases and other pollutants, impacting climate change. One approach to reducing residential energy consumption is through the use of smart energy management systems. However, automation from smart technology inherently removes a certain amount of control from the user. If loss of control is perceived as a loss of freedom, this may lead users to experience psychological reactance when using these products. A set of experiments was conducted to assess how three features of a message notification from smart home energy management systems may induce reactance in users. …

Optimization Of Transit Smart Card Data Publishing Based On Differential Privacy, Chenxi Chen

Masters Theses

“Privacy budget allocation is a key step of the differential privacy (DP)-based privacy-preserving data publishing (PPDP) algorithm development, as it directly impacts the data utility of the released dataset. This research describes the development of an optimal privacy budget allocation algorithm for transit smart card data publishing, with the goal of publishing non-interactive sanitized trajectory data under a differential privacy definition. To this end, after storing the smart card trajectory data with a prefix tree structure, a query probability model is built to quantitatively measure the probability of a trajectory location pair being queried. Next, privacy budget is calculated for …

The Effects Of Rigid Polyurethane Foam As A Confinement Material On Breaching Charge Detonations, Nathan Franz Paerschke-O'Brien

Masters Theses

"The effects of a rigid polyurethane foam used as a confinement material on four types of breaching explosives were tested, focusing on the changes in shockwave peak pressures, detonation load compression forces, and brisance cratering abilities. The Plate Dent testing procedure was modified to incorporate a load cell force sensor, and two air overpressure sensors were included adjacent to the blast to quantify each test result. The testing variables focused on the polyurethane foam cure times and thickness volumes around the breaching explosives to determine the breaching charges' optimal energy output capabilities when confined by the foam material. The rigid …

Investigation Of The Sensitivity Of Human Arm To Small Interaction Forces During Physical Human-Robot Interaction (Phri), Fazlur Rashid

Masters Theses

“Understanding the human motor control strategy during physical interaction tasks is crucial for developing future robots for physical human-robot interaction (pHRI). Effective pHRI depends on humans communicating their intentions for movement with robots. In physical human-human interaction (pHHI), small interaction forces are known to convey their intent between the partners. It is speculated that small interaction forces contain significant information to convey the movement intention of pHHI. However, the mechanism underlying this interaction strategy is largely unknown. Hence, the aim of this work was to investigate what affects humans’ sensitivity to the interaction forces. The hypothesis was that small interaction …

Development Of In-Situ Radiometric Inspection Methods For Quality Assurance In Laser Powder Bed Fusion, Cody S. Lough

Doctoral Dissertations

“Laser Powder Bed Fusion (LPBF) metal Additive Manufacturing (AM) fabricates 3D metal parts layer-by-layer. The process enables production of geometrically complex parts that are difficult to inspect with traditional methods. The LPBF parts experience significant geometry driven thermal variations during manufacturing. This creates microstructure and mechanical property inhomogeneities and can stochastically cause defects. Mission critical applications require part qualification by measuring the defects non-destructively. The layer-to-layer nature of LPBF permits non-intrusive measurement of radiometric signals for a part’s entire volume. These measurements provide thermal features that correlate with the local part health. This research establishes Optical Emission Spectroscopy (OES) and …

Advanced Battery Modeling For Interfacial Phenomena And Optimal Charging, Yaqi Zhu

Doctoral Dissertations

"Lithium-ion batteries are one of the most promising energy storage systems for portable devices, transportation, and renewable grids. To meet the increasing requirements of these applications, higher energy density and areal capacity, long cycle life, fast charging rate and enhanced safety for lithium-ion battery (LIBs) are urgently needed. To solve these challenges, the relevant physics at different length scale need to be understood. However, experimental study is time consuming and limited in small scale’s study. Modeling techniques provide us powerful tools to get a deep understanding of the relevant physics and find optimal solutions. This work focuses on studying the …

Prediction Of Battery Health Dynamics, Damola Martins Ajiboye

Doctoral Dissertations

"The successful market penetration of lithium-ion batteries in the last 30 years has ushered in a new dawn in energy applications. Notwithstanding their widespread use, lithium-ion batteries are affected by a plethora of fundamental issues — safety, cycle life, performance, and cost. In this work, advanced modeling techniques are developed to tackle some of these issues. This dissertation is subdivided into four parts, the first is introduction while the remaining are dedicated to the development of computational techniques for predicting battery health dynamics.

In the second part of this work, we developed fast and accurate algorithms for modeling essential battery …

Studying The Effects Of New Additive Materials For The Improvement Of The Capacity And Cycle Life Performance Of The Lead-Acid Battery, Julian Kosacki

Doctoral Dissertations

"Lead-acid batteries are an established technology with nearly 99% recyclability; however, lead-acid batteries produce only 40% of their theoretical capacity due to poor active mass utilization and PbSO4 pore blockage, and the longevity of the batteries is hampered by secondary reactions during the cycle life such as corrosion and gassing.

Lead-acid batteries were investigated and improved through several different approaches: an alternative electrolyte to mitigate secondary reactions, graphite additives to improve positive active mass (PAM) utilization, and dispersant additives to help the industrial pasting process.

The thermodynamics and chemical reactions of a commercial electrolyte replacement called Tydrolyte^TM were investigated …