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Full-Text Articles in Physical Sciences and Mathematics

Bridge Trisections And Classical Knotted Surface Theory, Jason Joseph, Jeffrey Meier, Maggie Miller, Miller Zupan Aug 2022

Bridge Trisections And Classical Knotted Surface Theory, Jason Joseph, Jeffrey Meier, Maggie Miller, Miller Zupan

Department of Mathematics: Faculty Publications

We seek to connect ideas in the theory of bridge trisections with other wellstudied facets of classical knotted surface theory. First, we show how the normal Euler number can be computed from a tri-plane diagram, and we use this to give a trisection-theoretic proof of the Whitney–Massey theorem, which bounds the possible values of this number in terms of the Euler characteristic. Second, we describe in detail how to compute the fundamental group and related invariants from a tri-plane diagram, and we use this, together with an analysis of bridge trisections of ribbon surfaces, to produce an infinite family of …


Feature Analysis Of Indus Valley And Dravidian Language Scripts With Similarity Matrices, Sarat Sasank Barla, Sai Surya Sanjay Alamuru, Peter Revesz Aug 2022

Feature Analysis Of Indus Valley And Dravidian Language Scripts With Similarity Matrices, Sarat Sasank Barla, Sai Surya Sanjay Alamuru, Peter Revesz

School of Computing: Conference and Workshop Papers

This paper investigates the similarity between the Indus Valley script and the Kannada, Malayalam, Tamil, and Telugu scripts that are used to write Dravidian languages. The closeness of these scripts is determined by applying a feature analysis of each sign of these scripts and creating similarity matrices that describe the similarity of any pair of signs from two different scripts. The feature list that we use for the analysis of these Dravidian language-related scripts includes six new features beyond the thirteen features that were used for the study of Minoan Linear A and related scripts by Revesz. These new features …


Multi-Method Investigation Of Factors Influencing Amyloid Onset And Impairment In Three Cohorts, Tobey J. Betthauser, Murat Bilgel, Rebecca L. Koscik, Bruno Jedynak, Yang An, Kristina A. Kellett, Abhay Moghekar, Erin M. Jonaitis, Charles K. Stone, Multiple Additional Authors Aug 2022

Multi-Method Investigation Of Factors Influencing Amyloid Onset And Impairment In Three Cohorts, Tobey J. Betthauser, Murat Bilgel, Rebecca L. Koscik, Bruno Jedynak, Yang An, Kristina A. Kellett, Abhay Moghekar, Erin M. Jonaitis, Charles K. Stone, Multiple Additional Authors

Mathematics and Statistics Faculty Publications and Presentations

Alzheimer’s disease biomarkers are becoming increasingly important for characterizing the longitudinal course of disease, predicting the timing of clinical and cognitive symptoms, and for recruitment and treatment monitoring in clinical trials. In this work, we develop and evaluate three methods for modelling the longitudinal course of amyloid accumulation in three cohorts using amyloid PET imaging. We then use these novel approaches to investigate factors that influence the timing of amyloid onset and the timing from amyloid onset to impairment onset in the Alzheimer’s disease continuum.

Data were acquired from the Alzheimer’s Disease Neuroimaging Initiative (ADNI), the Baltimore Longitudinal Study of …


Computer Aided Diagnosis System For Breast Cancer Using Deep Learning., Asma Baccouche Aug 2022

Computer Aided Diagnosis System For Breast Cancer Using Deep Learning., Asma Baccouche

Electronic Theses and Dissertations

The recent rise of big data technology surrounding the electronic systems and developed toolkits gave birth to new promises for Artificial Intelligence (AI). With the continuous use of data-centric systems and machines in our lives, such as social media, surveys, emails, reports, etc., there is no doubt that data has gained the center of attention by scientists and motivated them to provide more decision-making and operational support systems across multiple domains. With the recent breakthroughs in artificial intelligence, the use of machine learning and deep learning models have achieved remarkable advances in computer vision, ecommerce, cybersecurity, and healthcare. Particularly, numerous …


Role Of Deep Learning Techniques In Non-Invasive Diagnosis Of Human Diseases., Hisham Abouelseoud Elsayem Abdeltawab Aug 2022

Role Of Deep Learning Techniques In Non-Invasive Diagnosis Of Human Diseases., Hisham Abouelseoud Elsayem Abdeltawab

Electronic Theses and Dissertations

Machine learning, a sub-discipline in the domain of artificial intelligence, concentrates on algorithms able to learn and/or adapt their structure (e.g., parameters) based on a set of observed data. The adaptation is performed by optimizing over a cost function. Machine learning obtained a great attention in the biomedical community because it offers a promise for improving sensitivity and/or specificity of detection and diagnosis of diseases. It also can increase objectivity of the decision making, decrease the time and effort on health care professionals during the process of disease detection and diagnosis. The potential impact of machine learning is greater than …


Alkylthiocarbamate Metal Complexes With Antiproliferation Activity., Kritika Bajaj Aug 2022

Alkylthiocarbamate Metal Complexes With Antiproliferation Activity., Kritika Bajaj

Electronic Theses and Dissertations

Bis(thiosemicarbazones) (BTSCs) and their metal complexes have been extensively studied for various applications including catalysis for hydrogen evolution reactions, treatment of neurodegenerative diseases, hypoxia imaging, and a wide range of pharmacological purposes including antitumor, antiviral, antibacterial, and antifungal agents. The paramount property that makes BTSC metal complexes interesting for their use in these applications is the reduction potential of the coordinated metal, which can be selectively tuned by varying the substituents present on the ligand framework. Although the BTSCs have shown a great deal of success as potential cancer therapeutic agents, they lack selectivity towards cancer cells. For this matter, …


Dimension And Ramsey Results In Partially Ordered Sets., Sida Wan Aug 2022

Dimension And Ramsey Results In Partially Ordered Sets., Sida Wan

Electronic Theses and Dissertations

In this dissertation, there are two major parts. One is the dimension results on different classes of partially ordered sets. We developed new tools and theorems to solve the bounds on interval orders using different number of lengths. We also discussed the dimension of interval orders that have a representation with interval lengths in a certain range. We further discussed the interval dimension and semi dimension for posets. In the second part, we discussed several related results on the Ramsey theory of grids, the results involve the application of Product Ramsey Theorem and Partition Ramsey Theorem


A New Sir Model With Mobility., Ciana Applegate Aug 2022

A New Sir Model With Mobility., Ciana Applegate

Electronic Theses and Dissertations

In this paper, a mobility-based SIR model is built to understand the spread of the pandemic. A traditional SIR model used in epidemiology describes the transition of particles among states, such as susceptible, infected, and recovered states. However, the traditional model has no movement of particles. There are many variations of SIR models when it comes to the factor of mobility, the majority of studies use mobility intensity or population density as a measure of mobility. In this paper, a new dynamical SIR model, including the spatial motion of three-type particles, is constructed and the long-time behavior of the first …


Cross-Validation For Autoregressive Models., Christina Han Aug 2022

Cross-Validation For Autoregressive Models., Christina Han

Electronic Theses and Dissertations

There are no set rules for choosing the lag order for autoregressive (AR) time series models. Currently, the most common methods employ AIC or BIC. However, AIC has been proven to be inconsistent and BIC is inefficient. Racine proposed an estimator based on Shao's work which he hypothesized would also be consistent, but left the proof as an open problem. We will show his claim does not follow immediately from Shao. However, Shao offered another consistent method for cross validation of linear models called APCV, and we will show that AR models satisfy Shao's conditions. Thus, APCV is a consistent …


Estimating The Health Effects Of Adding Bicycle And Pedestrian Paths At The Census Tract Level: Multiple Model Comparison, Ross J. Gore, Christopher Lynch, Craig Jordan, Andrew Collins, R. Michael Robinson, Gabrielle Fuller, Pearson Ames, Prateek Keerthi, Yash Kandukuri Aug 2022

Estimating The Health Effects Of Adding Bicycle And Pedestrian Paths At The Census Tract Level: Multiple Model Comparison, Ross J. Gore, Christopher Lynch, Craig Jordan, Andrew Collins, R. Michael Robinson, Gabrielle Fuller, Pearson Ames, Prateek Keerthi, Yash Kandukuri

VMASC Publications

Background: Adding additional bicycle and pedestrian paths to an area can lead to improved health outcomes for residents over time. However, quantitatively determining which areas benefit more from bicycle and pedestrian paths, how many miles of bicycle and pedestrian paths are needed, and the health outcomes that may be most improved remain open questions.

Objective: Our work provides and evaluates a methodology that offers actionable insight for city-level planners, public health officials, and decision makers tasked with the question “To what extent will adding specified bicycle and pedestrian path mileage to a census tract improve residents’ health outcomes over time?” …


Adaptive Risk Network Dependency Analysis Of Complex Hierarchical Systems, Katherine L. Smith Aug 2022

Adaptive Risk Network Dependency Analysis Of Complex Hierarchical Systems, Katherine L. Smith

Computational Modeling & Simulation Engineering Theses & Dissertations

Recently the number, variety, and complexity of interconnected systems have been increasing while the resources available to increase resilience of those systems have been decreasing. Therefore, it has become increasingly important to quantify the effects of risks and the resulting disruptions over time as they ripple through networks of systems. This dissertation presents a novel modeling and simulation methodology which quantifies resilience, as impact on performance over time, and risk, as the impact of probabilistic disruptions. This work includes four major contributions over the state-of-the-art which are: (1) cyclic dependencies are captured by separation of performance variables into layers which …


Inexact Fixed-Point Proximity Algorithms For Nonsmooth Convex Optimization, Jin Ren Aug 2022

Inexact Fixed-Point Proximity Algorithms For Nonsmooth Convex Optimization, Jin Ren

Mathematics & Statistics Theses & Dissertations

The aim of this dissertation is to develop efficient inexact fixed-point proximity algorithms with convergence guaranteed for nonsmooth convex optimization problems encountered in data science. Nonsmooth convex optimization is one of the core methodologies in data science to acquire knowledge from real-world data and has wide applications in various fields, including signal/image processing, machine learning and distributed computing. In particular, in the context of image reconstruction, compressed sensing and sparse machine learning, either the objective functions or the constraints of the modeling optimization problems are nondifferentiable. Hence, traditional methods such as the gradient descent method and the Newton method are …


Design, Synthesis And Characterization Of Triazole Based Glycoconjugates And 4,6-Acetal Protected D-Glucosamine Derivatives As Low Molecular Weight Gelators, Pooja Sharma Aug 2022

Design, Synthesis And Characterization Of Triazole Based Glycoconjugates And 4,6-Acetal Protected D-Glucosamine Derivatives As Low Molecular Weight Gelators, Pooja Sharma

Chemistry & Biochemistry Theses & Dissertations

Low molecular weight gelators (LMWGs) are small molecules that can form gels in either organic solvents or water in their pure form or as mixtures. LMWGs self-assemble through noncovalent interactions such as hydrogen bonding, halogen bonding, van der Waals interactions and hydrophobic forces in solvents. They have shown great potential in biomedical industry, catalysis and environmental remediation to name a few. Moreover, the formation of metallogels can be used for detection of various ions as well as catalysis, which adds a new dimension to their applications. Among many classes of LMWGs based on the type of functional groups used, carbohydrate …


Kinetic And Structural Characterization Of Pseudooxynicotine Amine Oxidase From Pseudomonas Putida S16, Vishakha Choudhary Aug 2022

Kinetic And Structural Characterization Of Pseudooxynicotine Amine Oxidase From Pseudomonas Putida S16, Vishakha Choudhary

Masters Theses

Our laboratory has previously shown that nicotine oxidoreductase (NicA2), a member of the flavin-containing amine oxidase family, uses a cytochrome c protein (CycN) as its electron acceptor rather than characteristically accepted molecular oxygen. Within the Pseudomonas putida S16 genome, the nicA2 gene forms an operon with cycN and pseudooxynicotine amine oxidase (pnao), another flavin containing amine oxidase enzyme. The first two steps in the nicotine catabolism pathway are catabolized by NicA2 and Pnao. Through redox chemistry, NicA2 converts nicotine to pseudooxynicotine and Pnao converts pseudooxynicotine to 3-succinoylsemialdehyde-pyridine. In this thesis, we characterize the kinetic and structural properties of …


Controlling Textures In Tsp Art, Robert Bosch, Robert Klock Aug 2022

Controlling Textures In Tsp Art, Robert Bosch, Robert Klock

Faculty & Staff Scholarship

By making simple modifications to how we calculate distances between points/cities, we control textures in TSP Art.


El Niño And The Human-Environment Nexus: Drought And Vulnerability In Singapore 1877-1911, Fiona Williamson Aug 2022

El Niño And The Human-Environment Nexus: Drought And Vulnerability In Singapore 1877-1911, Fiona Williamson

Research Collection College of Integrative Studies

This chapter brings a climatic perspective to the study of Singaporean history by exploring the impacts of the strong El Niño inspired droughts of 1877, 1902 and 1911. The narrative focuses on unpacking the nexus of nature-inspired versus human-induced vulnerability to drought within the contexts of colonial urbanisation and looks at the short-to medium-term impacts of the events on society. It also explores how such events inspired new questions about the climate and regional teleconnections, as a wealth of evidence became available due to the increasingly connected nature of scientific institutions, scientific literature, and communications systems across the Indian Ocean …


Integrated Assessment Of Urban Overheating Impacts On Human Life, N. Nazarian, E. S. Krayenhoff, B. Bechtel, D. M. Hondula, R. Paolini, J. Vanos, T. Cheung, Winston T. L. Chow, Et Al Aug 2022

Integrated Assessment Of Urban Overheating Impacts On Human Life, N. Nazarian, E. S. Krayenhoff, B. Bechtel, D. M. Hondula, R. Paolini, J. Vanos, T. Cheung, Winston T. L. Chow, Et Al

Research Collection College of Integrative Studies

Urban overheating, driven by global climate change and urban development, is a major contemporary challenge that substantially impacts urban livability and sustainability. Overheating represents a multifaceted threat to the well-being, performance, and health of individuals as well as the energy efficiency and economy of cities, and it is influenced by complex interactions between building, city, and global scale climates. In recent decades, extensive discipline-specific research has characterized urban heat and assessed its implications on human life, including ongoing efforts to bridge neighboring disciplines. The research horizon now encompasses complex problems involving a wide range of disciplines, and therefore comprehensive and …


Visualizing Bivariate Statistics Using Ellipses Over A Scatter Plot, Mamunur Rashid, Jyotirmoy Sarkar, Siddhanta Phuyal Aug 2022

Visualizing Bivariate Statistics Using Ellipses Over A Scatter Plot, Mamunur Rashid, Jyotirmoy Sarkar, Siddhanta Phuyal

Mathematics Faculty Publications

A scatter plot shows the relationship between two quantitative variables 𝒙 and 𝒚. Sometimes, we can predict one variable as a linear function of the other using the least squares regression lines of 𝒚 on 𝒙 or 𝒙 on 𝒚. These two regression lines together suffice to identify the mean vector, the coefficient of determination, the correlation coefficient, and the ratio of the standard deviations (SD). So, do our proposed summary ellipses. Additionally, the inner ellipse reveals the SDs and the outer ellipse flags potential outliers.


Estimating The Parameters Of A Simple Linear Regression Model Without Using Differential Calculus, Mamunur Rashid, Jyotirmoy Sarkar Aug 2022

Estimating The Parameters Of A Simple Linear Regression Model Without Using Differential Calculus, Mamunur Rashid, Jyotirmoy Sarkar

Mathematics Faculty Publications

To estimate the parameters of a simple linear regression model, students who already know calculus can minimize the total squared deviations by setting its first-order partial derivatives to zero and solving simultaneously. For students who do not know calculus, most teachers/textbooks simply state the formulas without justifying them. Students accept the formulas on faith; and for given data, they evaluate the estimates using a calculator or a statistical software. In this paper, we justify the formulas without invoking calculus. We hope the users of statistics will benefit from our proposed justifications.


Semiparametric Estimation With Clustered Right Censored Data Via Multivariate Gaussian Random Fields, Fathima Zahra Sainul Abdeen Aug 2022

Semiparametric Estimation With Clustered Right Censored Data Via Multivariate Gaussian Random Fields, Fathima Zahra Sainul Abdeen

Doctoral Dissertations

Consider a fixed number of clustered areas identified by their geographical coordinate that are monitored for the occurrences of an event such as pandemic, epidemic, migration to name a few. Data collected on units at all areas include time varying covariates and other environmental factors that may affect event occurrences. The event times in every area can be independent. They can also be correlated with correlation between two units induced by an unobservable frailty. In both cases, the collected data is considered pairwise to account for spatial correlation between all pair of areas. The pairwise right censored data is probit-transformed …


An Integral Transform For Quantum Amplitudes, Jack C. Straton Aug 2022

An Integral Transform For Quantum Amplitudes, Jack C. Straton

Physics Faculty Publications and Presentations

The central impediment to reducing multidimensional integrals of transition amplitudes to analytic form, or at least to a fewer number of integral dimensions, is the presence of magnitudes of coordinate vector differences (square roots of polynomials) |x1−x2|2=x21−2x1x2cosθ+x2 √ in disjoint products of functions. Fourier transforms circumvent this by introducing a three-dimensional momentum integral for each of those products, followed in many cases by another set of integral transforms to move all of the resulting denominators into a single quadratic form in one denominator whose square my be completed. Gaussian transforms introduce a one-dimensional integral for each such product while squaring …


Secrep : A Framework For Automating The Extraction And Prioritization Of Security Requirements Using Machine Learning And Nlp Techniques, Shada Khanneh Aug 2022

Secrep : A Framework For Automating The Extraction And Prioritization Of Security Requirements Using Machine Learning And Nlp Techniques, Shada Khanneh

Theses, Dissertations and Culminating Projects

Gathering and extracting security requirements adequately requires extensive effort, experience, and time, as large amounts of data need to be analyzed. While many manual and academic approaches have been developed to tackle the discipline of Security Requirements Engineering (SRE), a need still exists for automating the SRE process. This need stems mainly from the difficult, error-prone, and time-consuming nature of traditional and manual frameworks. Machine learning techniques have been widely used to facilitate and automate the extraction of useful information from software requirements documents and artifacts. Such approaches can be utilized to yield beneficial results in automating the process of …


Investigating Elementary School Students’ Reasoning About Dynamic Angles, Erell Germia Aug 2022

Investigating Elementary School Students’ Reasoning About Dynamic Angles, Erell Germia

Theses, Dissertations and Culminating Projects

Angle measurement is a significant topic in almost all areas of mathematics learning and also in many disciplines outside mathematics education, such as engineering and architecture. According to the literature, there are three common conceptions of angles – as union of rays, rotations, and wedges. Researchers argued that students must consider these three angle concepts together to construct a meaningful understanding of angles. However, the curriculum standards for mathematics often present these angle conceptions separately to students, probably resulting in a fragmented understanding of the angle concept. In addition to this problem, the research literature documents multiple alternative conceptions that …


Secure Retrieval Of Encrypted Similar Documents Using Bloom Filters, German Guzman Aug 2022

Secure Retrieval Of Encrypted Similar Documents Using Bloom Filters, German Guzman

Theses, Dissertations and Culminating Projects

The ability to search for similar documents is a well-known problem on the Web and Information Retrieval field. For example, identifying similar profiles across different government agencies is an important process during intelligence gathering. Nonetheless, when data belongs to multiple parties, internal security policies and government regulations cannot allow the participating parties to freely share their sensitive documents. In our project, we aim to address the following problem: Given a user’s query Q and an encrypted database of documents stored on a third-party cloud server, we want to retrieve top-k documents similar to Q without disclosing Q and the contents …


Conservation Of Open-Canopy-Associated Wildlife: Multi-Scale Management Impacts On Imperiled Herpetofauna, Ethan Joseph Royal Aug 2022

Conservation Of Open-Canopy-Associated Wildlife: Multi-Scale Management Impacts On Imperiled Herpetofauna, Ethan Joseph Royal

Graduate Theses and Dissertations

The loss of open-canopy ecosystems throughout North America has precipitated declines in reptile and amphibian species associated with these habitat types. Current efforts to restore open-canopy ecosystems are underway in many areas, but the local distributions of, habitat characteristics required by and the effects of management actions on many herpetofauna species are poorly understood or entirely unknown. Research examining relationships among herpetofauna and their environments is often complicated by the extremely low detectability seen in many studies. We used landscape-scale, assemblage-level surveys to investigate the occupancy patterns and habitat associations of open-canopy-associated herpetofauna in two regions, as well as gain …


Weakly Q-Convex Domains And Bounded Q-Subharmonic Exhaustion Functions, Emily Foss Aug 2022

Weakly Q-Convex Domains And Bounded Q-Subharmonic Exhaustion Functions, Emily Foss

Graduate Theses and Dissertations

We generalize the Diederich-Fornaess index to bounded weakly q-convex domains with bounded q-subharmonic exhaustion functions. Sufficient conditions for this generalized Diederich-Fornæss index to have a given lower bound are proved. We show this generalized index is positive on bounded weakly q-convex domains with C^3 boundaries. Additionally, we prove sufficient conditions for this generalized index to equal one. For example, we show that if the domain has Property ( ̃(Pq ) ) then the domain has high hyperconvexity.


Structural Interpretation Of An Alkaline-Carbonatite Complex Using Gravity And Magnetic Methods At Magnet Cove, Arkansas, Chelsea Morgan Amaral Aug 2022

Structural Interpretation Of An Alkaline-Carbonatite Complex Using Gravity And Magnetic Methods At Magnet Cove, Arkansas, Chelsea Morgan Amaral

Graduate Theses and Dissertations

The Magnet Cove alkaline-carbonatite complex in the Ouachita Mountains of south-central Arkansas could be a valuable resource for rare earth elements, though it has not yet been thoroughly studied using geophysical methods, and existing geophysical models simplify its diverse nature. Prior to this study, the subsurface structure and extent of the Magnet Cove complex was poorly understood and, in general, the process of emplacement of alkaline carbonatite complexes worldwide is also not fully understood. The Magnet Cove complex hosts an extensive variety of rare rock types and mineral resources that contrast significantly to the sedimentary rocks into which they have …


Quantum Transport And Electric-Field Effects In Layered Topological Semimetals And Magnetic Materials, Arash Fereidouni Ghaleh Minab Aug 2022

Quantum Transport And Electric-Field Effects In Layered Topological Semimetals And Magnetic Materials, Arash Fereidouni Ghaleh Minab

Graduate Theses and Dissertations

This dissertation describes transport experiments on quantum devices in layered Dirac nodal line topological semimetals and antiferromagnetic materials down to a few layers. We used gate-induced effects to alter the transport properties of these materials.

First, we introduced current annealing in topological semimetals to achieve high-quality devices. We demonstrate current annealing to substantially improve the electronic transport properties of 2D topological semimetal flakes. Contact resistance and resistivity were improved by factors up to 2,000,000 and 20,000, respectively, in devices based on exfoliated flakes of two topological semimetals, ZrSiSe and BaMnSb2. Using this method, carrier mobility in ZrSiSe improved by a …


The Cosmic History Of X-Ray Binary Evolution, Woodrow Gilbertson Aug 2022

The Cosmic History Of X-Ray Binary Evolution, Woodrow Gilbertson

Graduate Theses and Dissertations

The Chandra Deep Fields provide an extraordinary window into the high-energy history of the cosmos. Observations of non-active galaxies within the deep fields can be leveraged to extract information about the formation and evolution of X-ray binaries (XRBs). Previous studies have suggested that the evolution of XRB luminosity can be expressed a function of physical parameters such as star formation rate, stellar mass, stellar age, and metallicity. The goal of this work is to develop and implement a complete physical parameterization for the luminosity of XRB populations, which can be utilized for a variety of further studies.

Chapter 1 provides …


Evaluation Of Carbon Isotopic Chemostratigraphy Of The Cedar Mountain Formation Of Utah, Clayton Forster Aug 2022

Evaluation Of Carbon Isotopic Chemostratigraphy Of The Cedar Mountain Formation Of Utah, Clayton Forster

Graduate Theses and Dissertations

The Lower Cretaceous rocks of Utah preserve the origin of a multitude of dinosaur taxa, spread of angiosperms on the North American continent, and evolution of marsupial and eutherian mammals. However, the timing of deposition of these rocks is not well understood and must be determined to understand climatic controls on these biological events. Estimates of the age of the Cedar Mountain Formation and its constituent members range from Late Jurassic to early Late Cretaceous. Understanding the timing of deposition of the Cedar Mountain Formation is critical to dinosaurian and associated taxa studies as well as paleoclimate reconstructions from within …