Physical Sciences and Mathematics Commons^™

A Framework To Study The Impact Of Interventions On Social Isolation During Pandemics Using Multi-Agent Simulation, Simranpreet Kaur

Electronic Theses and Dissertations

The spread of Coronavirus, widely known as COVID-19, has posed detrimental effects worldwide, affecting almost every primary sector. Due to its asymptomatic behavior and non-early diagnosis, government and health organizations implemented interventions such as physical distancing, lockdown, and quarantine, to mitigate the spread of the virus. Studies have shown that a connection exists between social isolation and health risks experienced by individuals. Thus, this research proposes an agent-based model to address the impact of varying interventions in our society. For simulation purposes, the SEIR model is followed, and agents are categorized into two classes based on their pace of movement, …

Variational Energies For The Rydberg P States Of Helium, Cody Mcleod

Electronic Theses and Dissertations

The aim of this work is to solve the quantum mechanical three-body problem for helium, and to obtain high precision eigenvalues for the higher-lying Rydberg states where previous methods have been of limited accuracy. A variational method in correlated Hylleraas coordinates is used involving three distinct distance scales, called a triple basis set. The eigenvalues and matrix elements of other operators are computed for P states of helium up to n = 15 using the varational method with a triple basis set in Hylleraas coordinates. The construction of the wave functions, as well as the behaviour of the asymptotic, intermediate …

Packing Non-Self-Crossing Edge-Disjoint Spanning Paths Into A Point Set, Rishav Chatterjee

Electronic Theses and Dissertations

The term packing refers to the arrangement of multiple geometrical structures or shapes such as circles, squares, triangles, or polygons into a fixed and finite set of points. The geometric structures to be packed can also be trees and paths. Packing is also possible in a 3-dimensional space with geometric structures such as spheres, cylinders, and cubes.

The concept of packing was introduced more than half a century ago. Since then, many researchers have studied the packing strategies of different geometric structures in different configurations of point-set. Packing strategies help to construct and arrange multiple geometric structures in a predetermined …

Traffic Sign And Light Detection Using Deep Learning For Automotive Applications, Humaira Naimi

Electronic Theses and Dissertations

Traffic sign and light detection are core components of Advanced Driver Assistance Systems (ADAS) and self-driving vehicles. The automotive industry is widely employing numerous approaches for automation through computer vision techniques. Object detection algorithms based on deep learning can be divided into two main categories, two stage and single stage detection algorithms. Two stage algorithms are designed to improve detection accuracy. While single stage algorithms are constructed to be faster, this increases their suitability for real time applications. This thesis presents a lightweight traffic sign and light detector by adapting a single stage, Single Shot Multibox Detection (SSD) algorithm by …

Content-Based Image Retrieval Using Hierarchical Decomposition Of Feature Descriptors, Eisa Adil

Electronic Theses and Dissertations

Due to modern technological advancements, the pervasiveness and complexity of images have remarkably increased. Searching databases for similar visual content, i.e., Content-Based Image Retrieval (CBIR), remains an open research problem. In this thesis, we propose a novel CBIR approach, in which each symbolic image has a quadtree representation consisting of SIFT-based orientational keypoints. Every quadrant node in the tree represents the dominant orientation of a region in the image. The quadtree image representation is used for bitwise signature indexing and image similarity measurement. Also, we convert each quadtree image representation to a trainable feature vector for use in the K-Nearest …

Neural Network-Based Multi-Task Learning For Product Opinion Mining, Manil Patel

Electronic Theses and Dissertations

Aspect Based Opinion Mining (ABOM) systems take user's reviews or posts as input from social media. The system aims to extract the aspect terms (e.g., pizza) and categories (e.g., food) and their polarities, to help the customers and identify product weaknesses. By solving these product weaknesses, companies can enhance customer satisfaction, increase sales, and boost revenues. Neural networks are widely used as classification algorithms for performing ABOM tasks for both the training (learning) phase from historical reviews to form class labels and the testing phase to predict the label for unknown data (new reviews). Neural network algorithms consist of artificial …

Novel Approaches To Cognitive Load Estimation In Automated Driving Systems, Prarthana Pillai

Electronic Theses and Dissertations

Automation has become indispensable in all walks of everyday life. In driving environments, Automated Driving Systems (ADS) aid the driver by reducing the required workload and by improving road safety. However, the present-day ADS requires the human driver to remain vigilant at all times and be ready to take over whenever the driving task requires. Thus, continuous monitoring of the drivers is important for adopting ADS. Such monitoring can be done in ADS by measuring the cognitive load experienced by the drivers. Studies show various methods to estimate cognitive load, however, the state of the art in cognitive load estimation, …

Discards & Diverse Economies: Reuse In Rural Maine, Brieanne Berry

Electronic Theses and Dissertations

This dissertation presents an ethnographic exploration of diverse reuse economies in rural Maine in an effort to illuminate both how used goods move between people and organizations, as well as the value of that movement for people and communities. In response to a growing number of calls for research into the social dimensions of circular economies, this research explores the varied and uneven impacts of materials reuse as they are experienced by local participants. This work uses a qualitative approach, drawing on two main methods: participant observation in reuse establishments and in-depth, semi-structured interviews with reuse participants. This rich qualitative …

Modern And Paleo Perspectives On The Role Of The Westerlies In Glaciation, Alexander Audet

Electronic Theses and Dissertations

Deciphering causes of glaciations and their abrupt terminations over the last >700,000 yrs remains an important problem for understanding the behavior of the climate system and how it might change in the future. In particular, the role of the Southern Hemisphere (SH) Westerlies in global change has arisen as an important research direction. Glaciers are highly sensitive to climate change. Examination of mid-latitude glaciers under the influence of westerly wind systems in both hemispheres can help provide insight into the role of the Westerlies in climate change. In this thesis, I present a twofold strategy to refine knowledge of the …

Quantifying Surface Changes On Mcmurdo Ice Shelf, Antarctica, Ann M. Hill

Electronic Theses and Dissertations

The amount of ice stored in Antarctica has the potential to raise sea level by almost 60 meters. Mass is primarily lost through glaciers draining the ice sheet and flowing into and ice shelves. Ice shelves float on the ocean and act as a resisting force to the flow of the glaciers, thereby modulating the flow of tributary glaciers, and consequently glacier contribution to global sea level rise. McMurdo Ice Shelf (MIS) buttresses four tributary glaciers, three of which will be discussed in this thesis, as well as the northwest corner of the faster flowing Ross Ice Shelf, which has …

Sulfur Isotope Composition Of Sulfides In Mafic Cumulates, Lesser Antilles Arc, Tyler Pollock

Electronic Theses and Dissertations

The sulfur isotope composition of sulfides in igneous rocks from magmatic arcs can be difficult to constrain due to the tendency for sulfur isotopes to fractionate during magma ascent and degassing. Cumulate xenoliths from the lower arc crust are representative of the most primitive magmas of the arc system. The Lesser Antilles arc presents a unique opportunity to investigate the sulfur isotope composition of arc magmas along a magmatic arc with many different magma plumbing systems. Here we present sulfur isotope compositions for primary magmatic sulfide inclusions and secondary interstitial hydrothermal sulfides in mafic cumulates from ten islands along the …

An Investigation Of Students' Use And Understanding Of Evaluation Strategies, Abolaji R. Akinyemi

Electronic Theses and Dissertations

One expected outcome of physics instruction is that students develop quantitative reasoning skills, including evaluation of problem solutions. To investigate students’ use of evaluation strategies, we developed and administered tasks prompting students to check the validity of a given expression. We collected written (N>673) and interview (N=31) data at the introductory, sophomore, and junior levels. Tasks were administered in three different physics contexts: the velocity of a block at the bottom of an incline with friction, the electric field due to three point charges of equal magnitude, and the final velocities of two masses in an elastic collision. Responses …

Asymmetric Synthesis Of Phosphate Mimics: From Chemistry To Biotechnology, Ahmed Numan

Electronic Theses and Dissertations

Oligonucleotide based therapeutics have been pursued in the clinic for the treatment of many disease indications. However, unmodified oligonucleotides are polyanionic macromolecules with poor drug-like properties. Modifications of the phosphodiester backbone provide resistance to nucleases in vivo, making them more efficacious than unmodified nucleotides. However, these backbone modifications have added the structural complexity of a stereogenic phosphorus center. Stereochemically pure isomers exhibit differential efficiency dependent on its enantiopurity. The catalytic, stereocontrolled synthesis of a phosphorus-stereogenic center is challenging, and traditionally, depends on a resolution or use of stochiometric auxiliaries. Herein, asymmetric nucleophilic catalysis has been investigated to provide enantio-enriched phosphonates …

Luminosity Functions Of Galaxy Clusters In The Aquarius And Microscopium Superclusters, Logan A. Hess

Electronic Theses and Dissertations

We examine physical properties of several galaxy clusters located within the Aquarius (AQR) and Microscopium (MSC) super-cluster complexes via their luminosity functions, fitted using Schechter functions. Images of clusters were acquired via the DECam (Dark Energy Camera) imager of the 4-meter diameter telescope at CTIO (Cerro Tololo Inter-American Observatory). We observe six clusters in our sample; four from the Aquarius supercluster (AQR 2541, 2546, 2554, 2555) and two from the Microscopium supercluster (MSC 3695, 3696). Magnitude information and density of member galaxies in each cluster were extracted via the SExtractor software utility from obtained images. We correct for background by …

To Know The Land With Hands And Minds: Negotiating Agricultural Knowledge In Late-Nineteenth-Century New England And Westphalia, Justus Hillebrand

Electronic Theses and Dissertations

Ever since the eighteenth century, experts have tried to tell farmers how to farm. The agricultural enlightenment in Europe marked the beginning of a long arc of new experts aiming to change agricultural knowledge and practice. This dissertation analyzes the pivotal period in the late nineteenth and early twentieth century in Germany and the United States when scientists, improvers, and market agents began to develop comprehensive ways to communicate agricultural innovation to farmers. In a functional approach to analyzing the negotiation of agricultural knowledge through its communication in things, words, and practices, this dissertation argues that the process of change …

Application Of Machine Learning Techniques To Classify And Identify Galaxy Merger Events In The Candels Field, Alex Koch

Electronic Theses and Dissertations

Galaxy mergers are dynamic systems that offer us a glimpse into the evolution of the cosmos and the galaxies that constitute it. However, with the advent of large astronomical surveys, it is becoming increasingly difficult to rely on humans to classify the vast number of astronomical images collected every year and find the images that capture these systems. In recent years, researchers have increasingly relied on machine learning and computer vision classifiers, and while these techniques have proven useful for classifying broad galaxy morphologies, they have struggled to identify galaxy mergers. A random forest classifier was applied to a subset …

Geology And Lithogeochemistry Of The Pickett Mountain Volcanogenic Massive Sulfide Deposit, Northern Maine, Michael J. Mccormick

Electronic Theses and Dissertations

The Pickett Mountain deposit is a volcanogenic massive sulfide (VMS) base-metal deposit located 15 miles north of Patten, ME. The deposit, discovered in 1979, was abandoned in 1989. The deposit remained abandoned until 2017, when Wolfden Mt. Chase LLC purchased the land for further development after Maine mining regulations changed. This project is a collaboration between the University of Maine, the University of Maine – Presque Isle, Wolfden Resources Corp., and the University of New Brunswick to better understand the regional and deposit-scale geology related to the deposit to fill in gaps of the geologic story of northern Maine as …

The Development And Optimization Of A Two-Dimensional Lc-Qqq-Ms-Method For The Combined Analysis Of Synthetic Cannabinoids And Designer Cathinones In Urine, Holly Penefsky

Electronic Theses and Dissertations

The compounds and chemical compositions of synthetic cannabinoids and designer cathinones are designed to mimic the intoxicating effects of D⁹-tetrahydrocannabinol and amphetamines, respectively. In order to skirt existing drug laws, non-controlled ingredients are used, and the original chemical structures of current drugs are being modified using analogs or derivatives. These continually changing chemical compositions pose a problem for policymakers, and forensic and analytical scientists, as users are able to attain a “legal high” and avoid detection in standard drug screens. Commonly, toxicology laboratories utilize a screening method, such as immunoassay, for the presumptive identification of designer drugs. When …

Investigation Of Ongoing Unconventional Gas Extraction And Underground Gas Storage In Pennsylvania: Regulations And Water Quality, Cassandra Ziegler

Electronic Theses and Dissertations

The extraction of unconventional shale gas and its underground gas storage have the potential to impact surface and groundwater water quality. In New Sewickley Township, Beaver County, Pennsylvania, 54 unconventional gas wells were drilled between 2013 and 2019. Groundwater samples from 33 water wells and surface water from Brush Creek (18 samples) were collected and analyzed for anions, cations, and light hydrocarbons. Results showed that at least 8 wells had indicators of brine contamination, and the surface waters of mine drainage. The Steckman Ridge natural gas storage field in Clearville, Bedford County, PA has 13 active storage wells. Samples were …

Impacts Of Oil And Gas Wastes On Landfill Leachate, Sewage Treatment Plants, And The Environment, Lauren Badertscher

Electronic Theses and Dissertations

Between January 2011 and March 2021 oil and gas wells in Pennsylvania produced

305,637,795 barrels of liquid waste and 6,992,957 tons of solid waste with the majority from

Marcellus Shale unconventional wells. This waste is not considered hazardous and over 89% of

the solid waste generated by unconventional and conventional oil and gas extraction has been

disposed of in landfills over the past decade. This study examined trends in the quantity of waste

produced and methods of disposal. Landfills accepting this waste were identified and their

general method of leachate treatment, using onsite facilities or offsite at wastewater treatment

plants, …

Development Of Standard Operating Procedure With Modified Method To Quantify Benzene And Other Volatile Organic Compounds In Air Samples Using Gas Chromatography, Heather Hall

Electronic Theses and Dissertations

Stephen F. Austin State University (SFASU) Department of Environmental Science has recently invested in a gas chromatograph which can be used to analyze air samples for volatile organic compounds (VOCs) such as benzene, toluene, ethylbenzene, and xylenes (BTEX). The goal of this project was to develop a standard operating procedure (SOP) and modify the current method for the detection of VOCs associated with oil and gas drilling activity to accommodate the equipment and capabilities of SFASU Environmental Assessment Lab. This study aims to provide the framework for future research in air quality monitoring in the Eagle Ford Shale area. An …

Seasonal Habitat Use Of Diamondback Terrapins (Malaclemys Terrapin) In North Inlet, Winyah Bay, Georgetown, South Carolina, Danielle Elizabeth Capella

Electronic Theses and Dissertations

No abstract provided.

Performance Comparison Of Imputation Methods For Mixed Data Missing At Random With Small And Large Sample Data Set With Different Variability, Kyei Afari

Electronic Theses and Dissertations

One of the concerns in the field of statistics is the presence of missing data, which leads to bias in parameter estimation and inaccurate results. However, the multiple imputation procedure is a remedy for handling missing data. This study looked at the best multiple imputation methods used to handle mixed variable datasets with different sample sizes and variability along with different levels of missingness. The study employed the predictive mean matching, classification and regression trees, and the random forest imputation methods. For each dataset, the multiple regression parameter estimates for the complete datasets were compared to the multiple regression parameter …

Applying Deep Learning To The Ice Cream Vendor Problem: An Extension Of The Newsvendor Problem, Gaffar Solihu

Electronic Theses and Dissertations

The Newsvendor problem is a classical supply chain problem used to develop strategies for inventory optimization. The goal of the newsvendor problem is to predict the optimal order quantity of a product to meet an uncertain demand in the future, given that the demand distribution itself is known. The Ice Cream Vendor Problem extends the classical newsvendor problem to an uncertain demand with unknown distribution, albeit a distribution that is known to depend on exogenous features. The goal is thus to estimate the order quantity that minimizes the total cost when demand does not follow any known statistical distribution. The …

Data Science And The Ice-Cream Vendor Problem, Makafui Azasoo

Electronic Theses and Dissertations

Newsvendor problems in Operations Research predict the optimal inventory levels necessary to meet uncertain demands. This thesis examines an extended version of a single period multi-product newsvendor problem known as the ice cream vendor problem. In the ice cream vendor problem, there are two products – ice cream and hot chocolate – which may be substituted for one another if the outside temperature is no too hot or not too cold. In particular, the ice cream vendor problem is a data-driven extension of the conventional newsvendor problem which does not require the assumption of a specific demand distribution, thus allowing …

Using An Inventory Of Unstable Slopes To Prioritize Probabilistic Rockfall Modeling And Acid Base Accounting In Great Smoky Mountains National Park, Thomas A. O'Shea

Electronic Theses and Dissertations

An inventory of unstable slopes along transportation corridors and performance modeling are important components of geotechnical asset management in Great Smoky Mountains National Park (GRSM). Hazards and risk were assessed for 285 unstable slopes along 151 miles of roadway. A multi-criteria model was created to select fourteen sites for two-dimensional probabilistic rockfall simulations and Acid Base Accounting (ABA) tests. Simulations indicate that rock material would likely enter the roadway at all fourteen sites. ABA test results indicate that influence of significant acid-producing potential is generally confined to slaty rocks of the Anakeesta Formation and graphitic schist of the Wehutty Formation. …

Analysis And Risk Estimation Of High Priority Unstable Rock Slopes In Great Smoky Mountains National Park, Tennessee And North Carolina, Samantha Farmer

Electronic Theses and Dissertations

Great Smoky Mountains National Park (GRSM) received 12.5 million visitors in 2020. With a high traffic volume, it is imperative roadways remain open and free from obstruction. Annual unanticipated rockfall events in GRSM often obstruct traffic flow. Using the Unstable Slope Management Program for Federal Land Management Agencies (USMP for FLMA) protocols, this study analyzes high priority unstable rock slopes through 1) creation of an unstable slope geodatabase and 2) generation of a final rockfall risk model using Co-Kriging from a preliminary risk model and susceptibility model. A secondary goal of this study is to provide risk estimation for the …

Manifold Learning With Tensorial Network Laplacians, Scott Sanders

Electronic Theses and Dissertations

The interdisciplinary field of machine learning studies algorithms in which functionality is dependent on data sets. This data is often treated as a matrix, and a variety of mathematical methods have been developed to glean information from this data structure such as matrix decomposition. The Laplacian matrix, for example, is commonly used to reconstruct networks, and the eigenpairs of this matrix are used in matrix decomposition. Moreover, concepts such as SVD matrix factorization are closely connected to manifold learning, a subfield of machine learning that assumes the observed data lie on a low-dimensional manifold embedded in a higher-dimensional space. Since …

Synthesis Of The Diazonium Zwitterionic Polymer/Monomer For Use As The Electrolyte In Polymer Electrolyte Membrane (Pem) Fuel Cells, Josiah Marshall

Electronic Theses and Dissertations

My research goals are to synthesize new zwitterionic perfluorosulfonimide (PFSI) monomer/polymers. They are expected to replace traditionally used perfluorosulfonic acid (PFSA) polymers as the electrolyte in PEM fuel cells. For the PFSI monomer preparation, we designed a nine-step synthesis route. Thus far, I have successfully completed the synthesis of 4- (2-bromotetrafluoroethoxy)-benzenesulfonyl amide, 4-acetoxybenzenesulfonic acid sodium salt, and 4-chlorosulfonyl phenyl acetate. The coupling reaction of 4-(2-bromotetrafluoroethoxy)- benzenesulfonyl amide with 4-chlorosulfonyl phenyl acetate, was troublesome due to slow reaction kinetics and byproducts. Additionally, I did a methodology study for the homopolymerziation of the perfluoro 3(oxapent-4-ene) sulfonyl fluoride monomer. We compared the weight …

The Food Truck Problem, Supply Chains And Extensions Of The Newsvendor Problem, Dennis Quayesam

Electronic Theses and Dissertations

Inventory control is important to ensuring sufficient quantities of items are available tomeet demands of customers. The Newsvendor problem is a model used in Operations Research to determine optimal inventory levels for fulfilling future demands. Our study extends the newsvendor problem to a food truck problem. We used simulation to show that the food truck does not reduce to a newsvendor problem if demand depends on exogenous factors such temperature, time etc. We formulate the food truck problem as a multi-product multi-period linear program and found the dual for a single item. We use Discrete Event Simulation to solve the …