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Full-Text Articles in Physical Sciences and Mathematics

Molecular Understanding And Design Of Deep Eutectic Solvents And Proteins Using Computer Simulations And Machine Learning, Usman Lame Abbas Jan 2024

Molecular Understanding And Design Of Deep Eutectic Solvents And Proteins Using Computer Simulations And Machine Learning, Usman Lame Abbas

Theses and Dissertations--Chemical and Materials Engineering

Hydrophobic deep eutectic solvents (DESs) have emerged as excellent extractants. A major challenge is the lack of an efficient tool to discover DES candidates. Currently, the search relies heavily on the researchers’ intuition or a trial-and-error process, which leads to a low success rate or bypassing of promising candidates. DES performance depends on the heterogeneous hydrogen bond environment formed by multiple hydrogen bond donors and acceptors. Understanding this heterogeneous hydrogen bond environment can help develop principles for designing high performance DESs for extraction and other separation applications. This work investigates the structure and dynamics of hydrogen bonds in hydrophobic DESs …


Recent Paleolimnological History Of Jackson Lake, Grand Teton National Park, Wyoming (Usa), Hillary Johnson Jan 2024

Recent Paleolimnological History Of Jackson Lake, Grand Teton National Park, Wyoming (Usa), Hillary Johnson

Theses and Dissertations--Earth and Environmental Sciences

This study utilizes a recently acquired, high-resolution CHIRP seismic reflection dataset and a deepwater sediment core to analyze the recent stratigraphy of Jackson Lake (Wyoming, USA). The western shoreline of Jackson Lake is situated adjacent to the Teton fault, a down-to-the-east normal fault that produces the spectacular high topography of Grand Teton National Park. The sediments of Jackson Lake are underexplored and consequently, their value as indicators of hydroclimatic and tectonic changes is unknown. Here, the sedimentary fill of Jackson Lake is explored as a natural archive of environmental change, specifically in reference to the influence of human outlet engineering …


Extracting Social Network Model Parameters From Social Science Literature, Isaac Batts Jan 2024

Extracting Social Network Model Parameters From Social Science Literature, Isaac Batts

Theses and Dissertations--Computer Science

When looking at computer modeling of social situations, much of the social science literature does not include ready-to-use statistics or parameters to be included in a social model. I explore studies related to speaking about racism (and other forms of bias), and interventions designed to diminish the occurrence of biased behavior, and use those readings to synthesize plausible parameters for a social computer model.


Nonuniform Sampling-Based Breast Cancer Classification, Santiago Posso Jan 2024

Nonuniform Sampling-Based Breast Cancer Classification, Santiago Posso

Theses and Dissertations--Electrical and Computer Engineering

The emergence of deep learning models and their success in visual object recognition have fueled the medical imaging community's interest in integrating these algorithms to improve medical diagnosis. However, natural images, which have been the main focus of deep learning models and mammograms, exhibit fundamental differences. First, breast tissue abnormalities are often smaller than salient objects in natural images. Second, breast images have significantly higher resolutions but are generally heavily downsampled to fit these images to deep learning models. Models that handle high-resolution mammograms require many exams and complex architectures. Additionally, spatially resizing mammograms leads to losing discriminative details essential …


Flexible Attenuation Fields: Tomographic Reconstruction From Heterogeneous Datasets, Clifford S. Parker Jan 2024

Flexible Attenuation Fields: Tomographic Reconstruction From Heterogeneous Datasets, Clifford S. Parker

Theses and Dissertations--Computer Science

Traditional reconstruction methods for X-ray computed tomography (CT) are highly constrained in the variety of input datasets they admit. Many of the imaging settings -- the incident energy, field-of-view, effective resolution -- remain fixed across projection images, and the only real variance is in the detector's position and orientation with respect to the scene. In contrast, methods for 3D reconstruction of natural scenes are extremely flexible to the geometric and photometric properties of the input datasets, readily accepting and benefiting from images captured under varying lighting conditions, with different cameras, and at disparate points in time and space. Extending CT …


Solid Angle Measure Approximation Methods For Polyhedral Cones, Allison Fitisone Jan 2024

Solid Angle Measure Approximation Methods For Polyhedral Cones, Allison Fitisone

Theses and Dissertations--Mathematics

Polyhedral cones are of interest in many fields, like geometry and optimization. A simple, yet fundamental question we may ask about a cone is how large it is. As cones are unbounded, we consider their solid angle measure: the proportion of space that they occupy. Beyond dimension three, definitive formulas for this measure are unknown. Consequently, devising methods to estimate this quantity is imperative. In this dissertation, we endeavor to enhance our understanding of solid angle measures and provide valuable insights into the efficacy of various approximation techniques.

Ribando and Aomoto independently discovered a Taylor series formula for solid angle …


On Generative Models And Joint Architectures For Document-Level Relation Extraction, Aviv Brokman Jan 2024

On Generative Models And Joint Architectures For Document-Level Relation Extraction, Aviv Brokman

Theses and Dissertations--Statistics

Biomedical text is being generated at a high rate in scientific literature publications and electronic health records. Within these documents lies a wealth of potentially useful information in biomedicine. Relation extraction (RE), the process of automating the identification of structured relationships between entities within text, represents a highly sought-after goal in biomedical informatics, offering the potential to unlock deeper insights and connections from this vast corpus of data. In this dissertation, we tackle this problem with a variety of approaches.

We review the recent history of the field of document-level RE. Several themes emerge. First, graph neural networks dominate the …


Magnetic Spin Transport Coils For The N2edm Experiment, David C. Bowles Jan 2024

Magnetic Spin Transport Coils For The N2edm Experiment, David C. Bowles

Theses and Dissertations--Physics and Astronomy

The n2EDM experiment is being construct at Paul Scherrer Institute to measure the electric dipole moment of the neutron (nEDM), in a search for new physics which could help explain the baryon asymmetry of the universe. To reach the experimental sensitivity goal of $d_n \sim 10^{-27}$, over an order of magnitude improvement from the current world limit, a spin polarization transfer efficiency of 99\% for ultracold neutrons entering or exiting the precession chamber is required, placing a stringent requirement on the adiabaticity of the magnetic field taper in the neutron guide system. The spin transport fields transition from 5~T (longitudinal) …


Language Models For Rare Disease Information Extraction: Empirical Insights And Model Comparisons, Shashank Gupta Jan 2024

Language Models For Rare Disease Information Extraction: Empirical Insights And Model Comparisons, Shashank Gupta

Theses and Dissertations--Computer Science

End-to-end relation extraction (E2ERE) is a crucial task in natural language processing (NLP) that involves identifying and classifying semantic relationships between entities in text. This thesis compares three paradigms for end-to-end relation extraction (E2ERE) in biomedicine, focusing on rare diseases with discontinuous and nested entities. We evaluate Named Entity Recognition (NER) to Relation Extraction (RE) pipelines, sequence-to-sequence models, and generative pre-trained transformer (GPT) models using the RareDis information extraction dataset. Our findings indicate that pipeline models are the most effective, followed closely by sequence-to-sequence models. GPT models, despite having eight times as many parameters, perform worse than sequence-to-sequence models and …


Slₖ-Tilings And Paths In ℤᵏ, Zachery T. Peterson Jan 2024

Slₖ-Tilings And Paths In ℤᵏ, Zachery T. Peterson

Theses and Dissertations--Mathematics

An SLₖ-frieze is a bi-infinite array of integers where adjacent entries satisfy a certain diamond rule. SL₂-friezes were introduced and studied by Conway and Coxeter. Later, these were generalized to infinite matrix-like structures called tilings as well as higher values of k. A recent paper by Short showed a bijection between bi-infinite paths of reduced rationals in the Farey graph and SL₂-tilings. We extend this result to higher kby constructing a bijection between SLₖ-tilings and certain pairs of bi-infinite strips of vectors in ℤᵏ called paths. The key ingredient in the proof is the relation to Plucker friezes and Grassmannian …


Adams Operations On The Burnside Ring From Power Operations, Lewis Dominguez Jan 2024

Adams Operations On The Burnside Ring From Power Operations, Lewis Dominguez

Theses and Dissertations--Mathematics

Topology furnishes us with many commutative rings associated to finite groups. These include the complex representation ring, the Burnside ring, and the G-equivariant K-theory of a space. Often, these admit additional structure in the form of natural operations on the ring, such as power operations, symmetric powers, and Adams operations. We will discuss two ways of constructing Adams operations. The goal of this work is to understand these in the case of the Burnside ring.


The Performance Of Marginal Modeling Methods For Rare Events With Application To Opioid Overdose Mortality And Morbidity, Shawn Nigam Jan 2024

The Performance Of Marginal Modeling Methods For Rare Events With Application To Opioid Overdose Mortality And Morbidity, Shawn Nigam

Theses and Dissertations--Epidemiology and Biostatistics

Opioid misuse is a nationwide epidemic, with Kentucky having one of the highest opioid overdose-related fatality rates across all US states. These rates have increased significantly over the past decade, with particularly large increases during the COVID-19 pandemic. This dissertation aims to study the behavior of these increases and the methods for the marginal modeling of count outcomes related to opioid overdose.

Opioid overdose-related fatality rates in Kentucky increased significantly during the COVID-19 pandemic. In this chapter, we characterize the changes in opioid overdose fatality rates in Kentucky and identify associations between potential factors and fatality rates. County-level opioid overdose …


Understanding Of Processing Additives Influence In Tin Halide Perovskites: Chemistry, Defect, And Photovoltaic Performance, Syed Rahmath Ullah Joy Jan 2024

Understanding Of Processing Additives Influence In Tin Halide Perovskites: Chemistry, Defect, And Photovoltaic Performance, Syed Rahmath Ullah Joy

Theses and Dissertations--Chemistry

Metal halide perovskite semiconductors have attracted much interest for various applications, such as solar cells, light emitting diodes, photodetectors, and lasers, due to their excellent optoelectronic properties. Photovoltaic cell development is centered on Pb-based perovskites, which have equal photovoltaic performance compared to the traditional silicon photovoltaic. But concerns arising from the usage of toxic lead metal have motivated the research community to seek an alternative derivative. Among those, tin halide perovskites show much promise as an alternative to Pb-counterparts due to their ideal bandgap for single junction photovoltaics and similar optoelectronic properties to Pb perovskites. Nevertheless, tin perovskites suffer from …


Properties Of Skew-Polynomial Rings And Skew-Cyclic Codes, Kathryn Hechtel Jan 2024

Properties Of Skew-Polynomial Rings And Skew-Cyclic Codes, Kathryn Hechtel

Theses and Dissertations--Mathematics

A skew-polynomial ring is a polynomial ring over a field, with one indeterminate x, where one must apply an automorphism to commute coefficients with x. It was first introduced by Ore in 1933 and since the 1980s has been used to study skew-cyclic codes. In this thesis, we present some properties of skew-polynomial rings and some new constructions of skew-cyclic codes. The dimension of a skew-cyclic code depends on the degree of its generating skew polynomial. However, due to the skew-multiplication rule, the degree of a skew polynomial can be smaller than its number of roots and hence tricky to …


Dirichlet Problems In Perforated Domains, Robert Righi Jan 2024

Dirichlet Problems In Perforated Domains, Robert Righi

Theses and Dissertations--Mathematics

We establish W1,p estimates for solutions uε to the Laplace equation with Dirichlet boundary conditions in a bounded C1 domain Ωε, η perforated by small holes in ℝd. The bounding constants will depend explicitly on epsilon and eta, where epsilon is the order of the minimal distance between holes, and eta denotes the ratio between the size of the holes and epsilon. The proof relies on a large-scale Lp estimate for ∇uε, whose proof is divided into two main parts. First, we show that solutions of an intermediate problem for a …


Cross-Layer Design Of Highly Scalable And Energy-Efficient Ai Accelerator Systems Using Photonic Integrated Circuits, Sairam Sri Vatsavai Jan 2024

Cross-Layer Design Of Highly Scalable And Energy-Efficient Ai Accelerator Systems Using Photonic Integrated Circuits, Sairam Sri Vatsavai

Theses and Dissertations--Electrical and Computer Engineering

Artificial Intelligence (AI) has experienced remarkable success in recent years, solving complex computational problems across various domains, including computer vision, natural language processing, and pattern recognition. Much of this success can be attributed to the advancements in deep learning algorithms and models, particularly Artificial Neural Networks (ANNs). In recent times, deep ANNs have achieved unprecedented levels of accuracy, surpassing human capabilities in some cases. However, these deep ANN models come at a significant computational cost, with billions to trillions of parameters. Recent trends indicate that the number of parameters per ANN model will continue to grow exponentially in the foreseeable …


Pairs Of Quadratic Forms Over P-Adic Fields, John Hall Jan 2024

Pairs Of Quadratic Forms Over P-Adic Fields, John Hall

Theses and Dissertations--Mathematics

Given two quadratic forms $Q_1, Q_2$ over a $p$-adic field $K$ in $n$ variables, we consider the pencil $\mathcal{P}_K(Q_1, Q_2)$, which contains all nontrivial $K$-linear combinations of $Q_1$ and $Q_2$. We define $D$ to be the maximal dimension of a subspace in $K^n$ on which $Q_1$ and $Q_2$ both vanish. We define $H$ to be the maximal number of hyperbolic planes that a form in $\mathcal{P}_K(Q_1, Q_2)$ splits off over $K$. We will determine which values for $(D, H)$ are possible for a nonsingular pair of quadratic forms over a $p$-adic field $K$.


Bicategorical Character Theory, Travis Wheeler Jan 2024

Bicategorical Character Theory, Travis Wheeler

Theses and Dissertations--Mathematics

In 2007, Nora Ganter and Mikhail Kapranov defined the categorical trace, which they used to define the categorical character of a 2-representation. In 2008, Kate Ponto defined a shadow functor for bicategories. With the shadow functor, Dr. Ponto defined the bicategorical trace, which is a generalization of the symmetric monoidal trace for bicategories. How are these two notions of trace related to one another? We’ve used bicategorical traces to define a character theory for 2-representations, and the categorical character is an example.


Computational Methods For Oi-Modules, Michael Morrow Jan 2024

Computational Methods For Oi-Modules, Michael Morrow

Theses and Dissertations--Mathematics

Computational commutative algebra has become an increasingly popular area of research. Central to the theory is the notion of a Gröbner basis, which may be thought of as a nonlinear generalization of Gaussian elimination. In 2019, Nagel and Römer introduced FI- and OI-modules over FI- and OI-algebras, which provide a framework for studying sequences of related modules defined over sequences of related polynomial rings. In particular, they laid the foundations of a theory of Gröbner bases for certain classes of OI-modules. In this dissertation we develop an OI-analog of Buchberger's algorithm in order to compute such Gröbner bases, as well …


Uniform Regularity Estimates For The Stokes System In Perforated Domains, Jamison R. Wallace Jan 2024

Uniform Regularity Estimates For The Stokes System In Perforated Domains, Jamison R. Wallace

Theses and Dissertations--Mathematics

We consider the Stokes equations in an unbounded domain $\omega_{\epsilon,\eta}$ perforated by small obstacles, where $\epsilon$ represents the minimal distance between obstacles and $\eta$ is the ratio between the obstacle size and $\epsilon$. We are able to obtain uniform $W^{1,q}$ estimates for solutions to the Stokes equations in such domains with bounding constants depending explicitly on $\epsilon$ and $\eta$.


Qcd Analysis Of Flavor-Nonchanging Hadronic Weak Processes Through Next-To-Leading Order, Girish Lingadahalli Muralidhara Jan 2024

Qcd Analysis Of Flavor-Nonchanging Hadronic Weak Processes Through Next-To-Leading Order, Girish Lingadahalli Muralidhara

Theses and Dissertations--Physics and Astronomy

Studies in quantum chromodynamics (QCD), the fundamental theory of the strong interactions, of low-energy hadronic weak processes utilize an effective Hamiltonian framework. Below the weak-mass scale, an effective Hamiltonian contains a series of Wilson coefficients and four-quark operators that come from the operator product expansion in the Standard Model. The effective hadronic Hamiltonian pertinent to a weak process is then obtained via a renormalization group analysis in QCD from the weak-mass scale to the low-energy scale of O(2 GeV). In this thesis, the construction and phenomenological implications of such an effective Hamiltonian for flavor-conserving, parity-violating quark processes in the Standard …


Exploring The Hot And Gaseous Universe From Infrared To X-Ray, Chamani Gunasekera Jan 2024

Exploring The Hot And Gaseous Universe From Infrared To X-Ray, Chamani Gunasekera

Theses and Dissertations--Physics and Astronomy

Over 90% of baryonic matter in the universe exists as astrophysical plasmas. The gas
is often far from thermodynamic equilibrium, so numerical non-equilibrium spectral
synthesis simulations are used to understand observations. cloudy simulates vari-
ous physical conditions, providing spectra predictions. This thesis aims to meet the
challenge of new observatories like the JWST (James Webb Space Telescope) and
XRISM (X-Ray Imaging Spectroscopy Mission). These simulations are no better
than the underlying atomic and molecular database and the fourth chapter details
a long-needed update to an evolving database. The predicted spectra are strongly
affected by the composition of the gas, which …


Autonomous Shuttle Car Docking To A Continuous Miner Using Rgb-Depth Imagery, Sky Rose Jan 2024

Autonomous Shuttle Car Docking To A Continuous Miner Using Rgb-Depth Imagery, Sky Rose

Theses and Dissertations--Mining Engineering

A great deal of research is currently being conducted in automating mining equipment to improve worker health and safety and increase mine productivity. Significant progress has been made in some applications, e.g., autonomous haul trucks for surface mining. However, little progress has been made in autonomous face haulage in underground room-and pillar coal mines. Accordingly, this thesis addresses automating the operation of a shuttle car, focusing on positioning the shuttle car under the continuous miner coal-discharge conveyor during cutting and loading operations. The approach uses a stereo depth camera as the sensor, and machine-learning algorithms are used to identify various …


Finite Mixtures Of Mean-Parameterized Conway-Maxwell-Poisson Models, Dongying Zhan Jan 2023

Finite Mixtures Of Mean-Parameterized Conway-Maxwell-Poisson Models, Dongying Zhan

Theses and Dissertations--Statistics

For modeling count data, the Conway-Maxwell-Poisson (CMP) distribution is a popular generalization of the Poisson distribution due to its ability to characterize data over- or under-dispersion. While the classic parameterization of the CMP has been well-studied, its main drawback is that it is does not directly model the mean of the counts. This is mitigated by using a mean-parameterized version of the CMP distribution. In this work, we are concerned with the setting where count data may be comprised of subpopulations, each possibly having varying degrees of data dispersion. Thus, we propose a finite mixture of mean-parameterized CMP distributions. An …


Enabling Dapps Data Exchange With Hardware-Assisted Secure Oracle Network, Yue Li Jan 2023

Enabling Dapps Data Exchange With Hardware-Assisted Secure Oracle Network, Yue Li

Theses and Dissertations--Computer Science

Decentralized applications (dApps), enabled by the blockchain and smart contract technology, are known for allowing distrustful parties to execute business logic without relying on a central authority. Compared to regular applications, dApps offer a wide range of benefits, including security by design, trustless transactions, and resistance to censorship. However, dApps need to access real-world data to achieve their full potential, relying on the data oracles. Oracles act as bridges between blockchains and the outside world, providing essential data to the smart contracts that power dApps. A significant challenge in integrating oracles into the dApp ecosystem is the Oracle Problem …


Using 3-Dimensional Mapping To Determine The Possibility Of Structural Control On Development Of The Upper Ordovician Lexington Limestone, Central Kentucky, U.S.A., Sean Davis Jan 2023

Using 3-Dimensional Mapping To Determine The Possibility Of Structural Control On Development Of The Upper Ordovician Lexington Limestone, Central Kentucky, U.S.A., Sean Davis

Theses and Dissertations--Earth and Environmental Sciences

The upper Lexington Limestone of Late Ordovician age has been interpreted to represent a structurally controlled, complex, facies mosaic. This facies mosaic has historically been interpreted to be a carbonate buildup of shoal complexes with interbedded shale units with intertonguing facies. Due to relatively recent advances in geographic-information-systems (GIS) mapping technologies, it is possible to generate three-dimensional (3-D) compatible maps to offer insight to the complexities of the upper Lexington Limestone and to determine if structural control affected the distribution of members. The resulting two-dimensional (2-D) and 3-D maps show that basement faults likely exerted a significant influence on facies …


The Appalachian System Of Basins And Platforms As A Tectonostratigraphic Analogue To The Barents Sea Shelf: Where Arctic Meets The Appalachians, Gustavo De Aguiar Martins Jan 2023

The Appalachian System Of Basins And Platforms As A Tectonostratigraphic Analogue To The Barents Sea Shelf: Where Arctic Meets The Appalachians, Gustavo De Aguiar Martins

Theses and Dissertations--Earth and Environmental Sciences

Divided between Norway and Russia, the Barents Sea shelf (BSS) is an ~1.4 million km2 Arctic province, containing significant hydrocarbon accumulations. However, much of the area is frontier, and geologic data are often restricted or unavailable. One strategy to mitigate lack of geologic data is the use of analogues from well-known, mature basins. Even though there have been attempts to use analogues to study the geology of the BSS, such use is limited. Moreover, no analogue, to my knowledge, has been capable of addressing the regional tectonostratigraphic development of the shelf as a whole.

In this research, the Appalachian …


Closing The Modern Seismic Gap Along The Teton Fault Via Seismic Mapping Of Mass Transport Deposits In Jackson Lake, Wy, Callia Jacqueline Cortese Jan 2023

Closing The Modern Seismic Gap Along The Teton Fault Via Seismic Mapping Of Mass Transport Deposits In Jackson Lake, Wy, Callia Jacqueline Cortese

Theses and Dissertations--Earth and Environmental Sciences

Terrestrial paleoseismological records along the Teton fault have historically indicated two-to-three major post-Pinedale (~14 ka) earthquake events, leaving an unresolved 6-9 m offset along the modern scarp. Recent studies of Jenny Lake have augmented this record, but the triggering mechanism is still equivocal until new paleo-earthquake records are developed. The earthquake record of the Teton fault is complicated by quiescence from ~5 ka to present, demonstrating the need for additional paleoseismic investigations. Compressed, high-intensity radar pulse (CHIRP) reflection data from Jackson Lake indicates multiple potentially seismically-induced mass transport deposits (MTDs). At least six MTD Groups representing chronostratigraphic intervals were interpreted …


A Source-To-Sink Analysis Of The Pantanal Basin (Brazil): Implications For Weathering, Erosion, And Landscape Evolution In The World's Largest Wetland, Edward L. Lo Jan 2023

A Source-To-Sink Analysis Of The Pantanal Basin (Brazil): Implications For Weathering, Erosion, And Landscape Evolution In The World's Largest Wetland, Edward L. Lo

Theses and Dissertations--Earth and Environmental Sciences

Large back-bulge retro-arc basins have limited information about the sediment composition, yet they comprise important parts of the stratigraphic rock record. The exorheic Pantanal Basin is the world's largest continental wetland that regulates many valuable ecosystem services (water storage, nutrient cycling, agriculture, ranching, tourism, and transportation). This dissertation is composed of three studies that utilize a suite of tools to examine the most fundamental basin-wide source-to-sink sediment processes and controls that affect the characteristics and distribution of modern sediments.

The first paper consists of a metadata analysis of 76 shallow tropical floodplain lakes in the literature with bathymetric data and …


Estimating Bedrock Shear Wave Velocity At Vsap, Paducah, Kentucky, Using Ambient Noise, Russel Rogers Jan 2023

Estimating Bedrock Shear Wave Velocity At Vsap, Paducah, Kentucky, Using Ambient Noise, Russel Rogers

Theses and Dissertations--Earth and Environmental Sciences

Due to the nature of the Mississippi Embayment region and its vicinity to the New Madrid Seismic Zone, earthquake ground-motion site effects are potential hazards and quantifying the associated hazard is a necessary step for public safety. Measuring the Vs contrast between bedrock and overlying soil layers is necessary for site effect evaluation. Various methodologies for investigating shear wave velocity (Vs) profiles have been implemented in the Mississippi Embayment. However, these previous studies provided a wide range of bedrock Vs. In this study, microtremor array measurements, utilizing ambient background noise, were used to provide an additional estimate …