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Using Numerical Relativity To Explore Strong Gravity And Develop Force-Free Electrodynamics Simulation Software With Best-Practice Development, Patrick E. Nelson

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this dissertation, we explore the effects of extremely strong gravitational and electro- dynamic fields using the techniques of numerical relativity. We use the existing black hole simulation software in the Einstein Toolkit to compute the spin-up of two initially nonspin- ning black holes as they pass by each other in space. The angular momentum is imparted by the tidal interaction between the two black holes, in a parallel to Earth’s tides, as described by classical mechanics, which also transfer angular momentum between the Earth’s rotation and the Moon’s orbit. The largest observed dimensionless spin observed was 0.20 with an …

Development Of Eccentric Black Hole Binary Searches In The Ligo And Pta Regimes, Belinda D. Cheeseboro

Graduate Theses, Dissertations, and Problem Reports (ETD)

In the past several years, a plethora of gravitational wave events have been detected leading to better understanding of binary black holes, binary neutron stars, and neutron star black hole binaries. All of these transient detections have helped us better understand the dynamics of these systems as well as the populations of these objects, but each of these sources was detected with models that neglected eccentricity. Eccentricity is one of several potential markers for determining the formation of binary systems. Detecting gravitational waves from eccentric sources can better our understanding of such systems and help constrain theories about their formation. …

Consensus Based Control Strategy For Virtual Synchronous Generators In Microgrids, Anusha Kandula

Graduate Theses, Dissertations, and Problem Reports (ETD)

Renewable energy sources such as photo-voltaic and wind energy are integrating very rapidly in power systems. These energy-based systems typically adopt power-electronic interfaced inverters to connect to the grid. However, unlike traditional generators, these sources have low inertia, resulting in system stability issues, especially in microgrids where they are the primary sources. To mitigate the low-inertia effect, the inverters are modeled as virtual synchronous generators (VSG), and their control is designed. The VSG emulates the inertia effect of the synchronous generator and maintains the stability of the system. Even though the droop control provides the primary control, it is insufficient …

Validation Of Shoulder Strain Index, Fabiha Islam

Graduate Theses, Dissertations, and Problem Reports (ETD)

Musculoskeletal disorders (MSDs) of shoulder are one of the most frequent and major causes of morbidity and pain among full-time workers in the USA. In 2018, shoulder disorders were the most severe type of MSDs in terms of lost workdays. Recent epidemiological studies have identified several biomechanical, organizational, and psychological factors that increase the risk of shoulder MSDs. Though multiple biomechanical studies have evaluated physical causal factors of shoulder MSDs with a goal of risk mitigation, literature lacks a standardized risk assessment tool. The main objective of this study was to validate a previously developed shoulder strain index. The strain …

Planning Algorithms Under Uncertainty For A Team Of A Uav And A Ugv For Underground Exploration, Matteo De Petrillo

Graduate Theses, Dissertations, and Problem Reports (ETD)

Robots’ autonomy has been studied for decades in different environments, but only recently, thanks to the advance in technology and interests, robots for underground exploration gained more attention. Due to the many challenges that any robot must face in such harsh environments, this remains an challenging and complex problem to solve.

As technology became cheaper and more accessible, the use of robots for underground ex- ploration increased. One of the main challenges is concerned with robot localization, which is not easily provided by any Global Navigation Services System (GNSS). Many developments have been achieved for indoor mobile ground robots, making …

Identical Twins As A Facial Similarity Benchmark For Human Facial Recognition, John Andrew Mccauley

Graduate Theses, Dissertations, and Problem Reports (ETD)

The problem of distinguishing identical twins and non-twin look-alikes in automated facial recognition (FR) applications has become increasingly important with the widespread adoption of facial biometrics. Due to the high facial similarity of both identical twins and look-alikes, these face pairs represent the hardest cases presented to facial recognition tools. This work presents an application of one of the largest twin datasets compiled to date to address two FR challenges: 1) determining a baseline measure of facial similarity between identical twins and 2) applying this similarity measure to determine the impact of doppelgangers, or look-alikes, on FR performance for large …

Single And Differential Morph Attack Detection, Baaria Chaudhary

Graduate Theses, Dissertations, and Problem Reports (ETD)

Face recognition systems operate on the assumption that a person's face serves as the unique link to their identity. In this thesis, we explore the problem of morph attacks, which have become a viable threat to face verification scenarios precisely because of their inherent ability to break this unique link. A morph attack occurs when two people who share similar facial features morph their faces together such that the resulting face image is recognized as either of two contributing individuals. Morphs inherit enough visual features from both individuals that both humans and automatic algorithms confuse them. The contributions of this …

Asymmetry Risk And Asset Pricing, Jiahao Gu

Graduate Theses, Dissertations, and Problem Reports (ETD)

The dissertation primarily focuses on asymmetry risk and its role in asset pricing. Asymmetry risk is a crucial component of systematic risk. However, it does not attract much attention, probably because of the misconception that it is similar to other asymmetry measures (e.g., skewness). Chapter 1 defines the asymmetry risk. The risk indifference curve (RIC) predicts two asymmetry premiums in the return distribution rather than one in the downside. I also derive the risk-neutral measure of asymmetry risk.

Chapter 2 empirically investigates the asymmetry beta's return predictability and tail risk hedging ability. Consistent with the risk indifference curve, the asymmetry …

Modified Firearm Discharge Residue Analysis Utilizing Advanced Analytical Techniques, Complexing Agents, And Quantum Chemical Calculations, William J. Feeney

Graduate Theses, Dissertations, and Problem Reports (ETD)

The use of gunshot residue (GSR) or firearm discharge residue (FDR) evidence faces some challenges because of instrumental and analytical limitations and the difficulties in evaluating and communicating evidentiary value. For instance, the categorization of GSR based only on elemental analysis of single, spherical particles is becoming insufficient because newer ammunition formulations produce residues with varying particle morphology and composition. Also, one common criticism about GSR practitioners is that their reports focus on the presence or absence of GSR in an item without providing an assessment of the weight of the evidence. Such reports leave the end-used with unanswered questions, …

Optimization Of Operating Conditions And Design Parameters On Coal Ultra-Fine Grinding Through Kinetic Stirred Mill Tests And Numerical Modeling, Francisco Patino

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study investigated the ultra-fine coal grinding performance of four low- to moderate-cost grinding media: ceramic balls, granular sand, alumina beads, and silica beads. The kinetic grinding tests were conducted using a stirred mill, while different operating conditions, including the media size, solids concentration, and the addition of viscosity modifiers, were examined. Characterization studies in terms of particle size, shape, and surface morphology were further performed to support the experimental findings. Moreover, using population balance modeling, grinding simulation was performed in Matlab to forecast the particle size distribution based on the specific energy input and experimental size-related data. The results …

Development Of Multi-Catchment Rating Curves For Streams Of Appalachian Mixed-Land-Use Watersheds: Preliminary Results, Zachary A. Heck

Graduate Theses, Dissertations, and Problem Reports (ETD)

Anthropogenic activities can alter the quantity and quality of water. Traditional monitoring of streamflow involves measurements of stage (mm), or water height, and discharge (i.e., streamflow) (m3 s -1 ) above a local datum. However, while stage is relatively easily monitored, continuous streamflow measurement is often impractical and prohibitively expensive. To address this challenge, rating curve equations can be developed to convert stage to flow. To establish a series of rating curves for flow estimations in Appalachia, an investigation was conducted in a representative urbanizing, mixed-land-use watershed in north-central West Virginia consisting of 21 nested stream gauge sites. At each …

More Than One Story: A Bioecological Model Of Elementary Educators’ Perceptions And Representations Of Diversity, Angela Curfman

Graduate Theses, Dissertations, and Problem Reports (ETD)

Classroom teachers have long employed children’s literature in the classroom. Exposure to children’s literature offers a plethora of gains and benefits. Through the usage of children’s literature, critical thinking skills are fostered and factual information is obtained (Hancock, 2000). Varied cultures, linguistic backgrounds, families with diverse socio-economical, and academic backgrounds constitute our public school classrooms. Children’s literature provides readers an opportunity for self-affirmation; therefore, they often seek a mirror in books, (Bishop, 1990). The thoughtful selection of children’s literature in the classroom is essential. Through the lens of Bishop’s (1993) metaphorical notion of books as mirrors, windows, and sliding glass …

Identification And Classification Of Radio Pulsar Signals Using Machine Learning, Di Pang

Graduate Theses, Dissertations, and Problem Reports (ETD)

Automated single-pulse search approaches are necessary as ever-increasing amount of observed data makes the manual inspection impractical. Detecting radio pulsars using single-pulse searches, however, is a challenging problem for machine learning because pul- sar signals often vary significantly in brightness, width, and shape and are only detected in a small fraction of observed data.

The research work presented in this dissertation is focused on development of ma- chine learning algorithms and approaches for single-pulse searches in the time domain. Specifically, (1) We developed a two-stage single-pulse search approach, named Single- Pulse Event Group IDentification (SPEGID), which automatically identifies and clas- …

Geology Oriented Loading Approach For Underground Coal Mines, Deniz Tuncay

Graduate Theses, Dissertations, and Problem Reports (ETD)

Mining-induced stresses in underground coal mines play a significant role in pillar and support design, hence in the safety of mining operations. Adequate design of pillars and roof control plans rely on the accurate assessment of the mining-induced loads, as well as the load-bearing capacities of the supports. In pillar design tools frequently used by the underground coal mining industry and Mine Safety and Health Administration (MSHA), overburden loading is estimated by geometric concepts such as the tributary area and the abutment angle method. These methods do not explicitly consider important mechanical responses such as specific overall ground behavior. The …

Modeling, Optimization And Uncertainty Quantification Of Solids-Based Co2 Capture Technologies, Anca Ostace

Graduate Theses, Dissertations, and Problem Reports (ETD)

Solids-based carbon dioxide (CO₂)adsorption, where CO₂ is adsorbed under high pressure/low temperature and desorbed at low pressure/high temperature, is a low energy consumption capture technology with high carbon uptake efficiency. Chemical looping combustion (CLC), where a solid oxygen carrier (OC) transports oxygen between two high-temperature reactors – a fuel and an air reactor –, is a low energy penalty, fuel-flexible technology with inherent CO₂ capture for power/heat and syngas production.

In this work, state-of-the-art equation-oriented (EO) mathematical models of a fixed-bed (FxB) contactor for CO₂ adsorption and moving-bed (MB) reactors for gas-, and solid-fueled CLC …

Microwave-Assisted Natural Gas Conversion To Value-Added Chemicals, Xinwei Bai

Graduate Theses, Dissertations, and Problem Reports (ETD)

Stranded gas is a raw gas mixture of volatile hydrocarbons where the main composition is methane. The producers flare the stranded gas at the site because the cost of collecting and transporting the gas is higher than the value of the gas itself. To reduce the waste of this natural resource, it is worthwhile to utilize the on-site stranded natural gas as feedstock to produce value-added chemicals without emitting greenhouse gas. Direct natural gas conversion process is more desirable because of lower capital investment. Methane and ethane, the two major components of natural gas, are very stable molecules that usually …

Modeling Gas Migration During A Gas Kick, Ali Zankawi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Gas kick is an undesirable problem in the oil and gas industry, which can potentially interfere with the production process and damage drilling equipment. The primary intent of this study is to highlight gas migration and its effect on gas kick mitigation approaches that would benefit the petroleum industry. The integrated analysis provides valuable insight regarding parameters promoting efficient drilling and production processes, Minimizing the risk of gas kicks. This study aimed to investigate the impact of critical parameters on gas migration during the gas kick in both water- and oil-based mud and promote the understanding of the dynamics of …

Analysis Of Millimeter-Wave Networks: Blockage, Antenna Directivity, Macrodiversity, And Interference, Enass Hriba

Graduate Theses, Dissertations, and Problem Reports (ETD)

Due to its potential to support high data rates at low latency with reasonable interference isolation because of signal blockage at these frequencies, millimeter-wave (mmWave) communications has emerged as a promising solution for next-generation wireless networks. MmWave systems are characterized by the use of highly directional antennas and susceptibility to signal blockage by buildings and other obstructions, which significantly alter the propagation environment. The received power of each transmission depends on the direction the corresponding antennas point and whether the signal’s path is line-of-sight (LOS), non-LOS (i.e., partially blocked), or completely blocked. A key challenge in modeling blocking in mmWave …

Neural Networks And Sensitivity Analysis For Detection And Interpretation Of Structural Damage, Dayakar Naik Lavadiya

Civil and Environmental Engineering

Computer vision (CV)-based approaches have gained a lot of attention in recent years for objective identification of damages both at structural and material scales. In this dissertation, the metallurgical phases and the two important modes of damage in structural steel, namely fracture and corrosion, are considered. Use of CV techniques for metallurgical phase identification and fracture type identification in steel microstructure is minimal and rely on pixel intensity information. When distinct phases or fracture types possess similar pixel intensities, predictions may be erroneous. In this dissertation, various texture recognition algorithms based on an ensemble of machine learning algorithms are proposed …

Image Registration And Fusion Application, Shreya Singh

Computer Science

Image Registration and Fusion is a process of manipulating two or more input images through a combination of geometric transformation operations and fusion rules to obtain the information from the input images into one fused image. Currently, most existing image registration and fusion techniques are appropriate for grayscale images. There are a few techniques which support colored images but cannot be used for a large input data set. The aim of this research is to propose an image registration and fusion technique that supports large input data sets of both grayscale and colored images. To this end, we explored various …

Investigating Super Learner On Healthcare Data Sets, Humaira Rahman

Computer Science

In the field of machine learning, classification is the essential task that predicts the target class or label for each sample in the data. Improving the performance of a classification model has been a challenging research problem. Researchers try to choose the proper techniques and combine several algorithms to be applied to the specific data set to get better predictions. Nowadays, researchers have used the method called super learner. The idea of super learning is that it combines multiple techniques as base learners and uses a meta-learner to get the final predictions and thus obtain more reliable results. In this …

Development Of An Algorithm For Detection And Recovery Of Corruption In Convolutional Neural Networks Data Storage, Mohammadreza Ramzanpour

Computer Science

Computer vision based applications are commonly utilized in embedded systems. The demand for higher accuracy leads to increased complexity of convolutional neural networks (CNN) and hence, larger storage requirement for saving pre-trained networks. Even the smallest data corruption in the storage units of the embedded systems can result in drastic failures due to the propagation of the errors. This thesis proposes a new algorithm for the recovery of the data in case of single event upset (SEU) error. An association rule mining based algorithm is used to find the probability of corruption in each of the bits. The recovery algorithm …

Crushed By Covid-19 Medical Bills, Coronavirus Victims Need Debt Relief Under The Bankruptcy Code And Workers' Compensation Laws, Creola Johnson

Penn State Law Review (2003 - Present)

No abstract provided.

Environmental Factors Influencing Tumor Associated Pericyte Phenotype In Pancreatic Cancer, Alexander Delgado

Biological Sciences

Pancreatic ductal adenocarcinoma (PDAC) is the third leading cause of cancer death in the U.S. with a 5-year survival rate of 11%. PDAC patients suffer from the lack of effective treatment options largely due to the limited delivery efficacy of the drugs. Tumor vessels are abnormal, leaky, and lack proper pericyte coverage, contributing to elevated hypoxia and interstitial fluid pressure, promoting cancer progression and metastasis, and inhibiting drug delivery efficacy. In the case of PDAC, a large portion of blood vessels were covered by α-smooth muscle actin (αSMA) expressing pericyte, which is normally absent in capillary pericytes. We also showed …

An Evaluation Of The Social Perceptions And Biological Efficacy Of Unmanned Aircraft Systems For Avian-Agriculture Conflict, Mallory Gyovai White

Biological Sciences

North Dakota sunflower producers face a dilemma when it comes to blackbirds (Icteridae). Migrating flocks produce localized damage to production, which results in some farmers with no bird issues, while others face total economic losses. A dynamic and humane crop protection tool is necessary to reduce blackbird damage in this broad-scale agriculture setting, as damage is actively occurring, while considering the protected status of blackbirds. This study examined a novel tool, unmanned aircraft systems (hereafter, UAS), through the lens of a social evaluation of farmers’ opinions and the biological impact on blackbird flock behavior. Farmers were very willing to allow …

Business Risk, Financial Risk, And Liquidity Management On U.S. Farms - Evidence From Selected States, Emin Allahverdiyev

Agribusiness and Applied Economics

Risk management is pivotal to agribusiness decision-making, and researchers have developed various models to disentangle factors underlying farmers’ risk decisions. This thesis argues that an appropriate model should consider farmers’ leverage decisions altogether with liquidity decisions given that liquidity is another major constraint facing farm businesses. We incorporate current ratio into the classical risk balancing model. Our theoretical derivations generate two propositions: (1) an increase in business risk will cause current assets to increase, and (2) an increase in the expected return to assets will cause current assets to decrease. Using five income categories and three panel data models, regression …

Ex-Ante Temporal Optimization In Soybean Origination: An Overdetermined Approach Through Deep Learning, Noah Joseph Carlson

Agribusiness and Applied Economics

Digitization is influencing commodity trading and agricultural markets and as they transition towards extreme liquidity, agribusiness risk exposures increase, and traditional competitive advantages diminish. In commodity origination, logistics and destination basis comprise the most volatile and determinant influences of margin. To capture a consistently higher margin and represent narrowed interior basis, agribusiness firms must manage these risks by optimizing transformations. To accomplish this, ex-ante decision-making is often necessary as forward price clairvoyance is not always prevalent, is risky, or contains premium. Modeling this spatial equilibrium is difficult through traditional reductionist and essentialist application as the overdetermined and convoluted system presents …

Optimization Of Coverage Ratios For Basis And Freight Trading Portfolios, Adam Joseph Kroll

Agribusiness and Applied Economics

Changing commodity prices create opportunities for traders to profit or experience substantial losses if risk is not managed. Extensive research has been presented regarding optimal hedging strategies using futures markets to mitigate price risk of holding a physical commodity, but the literature has not introduced a method for optimizing basis or rail coverage ratios. This study introduces coverage ratios to manage basis and transportation risk. Coverage ratios are optimized for a portfolio of basis and rail positions consistent with expected utility theory using Monte Carlo simulation at various risk aversion levels. The results indicated that as risk aversion increased, optimal …

The United States And Brazil - Spatial And Logistical Interdependence For Soybean Shipments To China, Gwen Marie Scheresky

Agribusiness and Applied Economics

Analyzing the United States/Brazil competition for market share of Chinese soybean imports requires a detailed, stochastic approach. Using data from 2013 to 2019, this thesis attempts to model and explain the change in market share for each producing country as different variables fluctuate or enter the equation. Using five origins in each country, the PNW, USG, Santos, Paranaguá, and the northern arc of ports in Brazil, various transportation routes from origin to port, congestion and quality metrics, and ocean freight, a least-cost optimized Monte Carlo simulation is performed using time-series forecasting distributions for monthly variables. A distribution of outcomes for …

Implementing High-Throughput Phenotyping At The Ndsu Dry Bean (Phaseolus Vulgaris L.) Breeding Program Using Unmanned Aerial Systems, Diego Jose Gris

Agribusiness and Biosystems Engineering

Plant breeding has led to considerable yield gains to several crops. However, it alone might not be able to keep up with the growing demand for food. In this study, data extracted from UAS-collected RGB and multispectral images were assessed on their ability to estimate four agronomic traits in three market classes of dry beans in a breeding program. The results showed that (i) seed yield, 100-seed weight, stem diameter and days to flowering can be estimated within the same market class with variable accuracy; (ii) aggregating data from several flights yielded better results than using a single flight; (iii) …