Open Access. Powered by Scholars. Published by Universities.®

Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

2020

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 271 - 300 of 1327

Full-Text Articles in Mathematics

A 3d Image-Guided System To Improve Myocardial Revascularization Decision-Making For Patients With Coronary Artery Disease, Haipeng Tang Aug 2020

A 3d Image-Guided System To Improve Myocardial Revascularization Decision-Making For Patients With Coronary Artery Disease, Haipeng Tang

Dissertations

OBJECTIVES. Coronary artery disease (CAD) is the most common type of heart disease and kills over 360,000 people a year in the United States. Myocardial revascularization (MR) is a standard interventional treatment for patients with stable CAD. Fluoroscopy angiography is real-time anatomical imaging and routinely used to guide MR by visually estimating the percent stenosis of coronary arteries. However, a lot of patients do not benefit from the anatomical information-guided MR without functional testing. Single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) is a widely used functional testing for CAD evaluation but limits to the absence of anatomical information. …


Why 3d Fragmentation Usually Leads To Cuboids: A Simple Geometric Explanation, Laxman Bokati, Olga Kosheleva, Vladik Kreinovich Aug 2020

Why 3d Fragmentation Usually Leads To Cuboids: A Simple Geometric Explanation, Laxman Bokati, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

It has been empirically observed that the average shape of natural fragmentation results -- such as natural rock fragments -- is a distorted cube (known as cuboid). Recently, a complex explanation was provides for this empirical fact. In this paper, we propose a simple geometry-based physical explanation for the ubiquity of cuboid fragments.


Two Runners In The Time Of Social Distancing, Speedboats In The Gulf Of Finland: How To Best Pass?, Julio Urenda, Olga Kosheleva, Vladik Kreinovich Aug 2020

Two Runners In The Time Of Social Distancing, Speedboats In The Gulf Of Finland: How To Best Pass?, Julio Urenda, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

If two runners follow the same running path, what is the best trajectory for the faster runner to pass the slower one, taking into account that they should always maintain a prescribed social distance? If a speedboat wants to pass a slower ship following a special canal in the Gulf of Finland, what is the best trajectory? In this paper, we provide answers to both questions.


New Development Of Grid Generation And Image Analysis, Ben Hildebrand Aug 2020

New Development Of Grid Generation And Image Analysis, Ben Hildebrand

Mathematics Dissertations - Archive

Image segmentation and registration are indispensable tools for the aid in medical diagnoses by experts. The current gold-standard for image segmentation is manual labeling of pixels by experts which is cumbersome and inefficient. In a paper by Zhu et. al. grids are generated through the deformation method for grid generation and differential properties of these grids are used in a deep learning algorithm for image segmentation. In this dissertation, we develop a new method for generating grid images based on the Variational Method. This new grid generation method generates grids based on image pixel intensities which improves upon the deformation …


Analyzing The Fractal Dimension Of Various Musical Pieces, Nathan Clark Aug 2020

Analyzing The Fractal Dimension Of Various Musical Pieces, Nathan Clark

Industrial Engineering Undergraduate Honors Theses

One of the most common tools for evaluating data is regression. This technique, widely used by industrial engineers, explores linear relationships between predictors and the response. Each observation of the response is a fixed linear combination of the predictors with an added error element. The method is built on the assumption that this error is normally distributed across all observations and has a mean of zero. In some cases, it has been found that the inherent variation is not the result of a random variable, but is instead the result of self-symmetric properties of the observations. For data with these …


Asymptotic Normality Of The Deconvolution Kernel Density Estimators Based On Independent As Well As Strong Mixing Right Censored Data, Wenqing Zhu Aug 2020

Asymptotic Normality Of The Deconvolution Kernel Density Estimators Based On Independent As Well As Strong Mixing Right Censored Data, Wenqing Zhu

Mathematics Dissertations - Archive

We consider estimation of a density when observed lifetime from the convolution model contaminated by additive measurement errors. A kernel type deconvolution density estimator of the unknown distribution based on right censored data is proposed by using the Inverse-Probability-of-Censoring Weighted Average. Further, we discuss the asymptotic normality of the deconvolution kernel density estimators for independent and strong mixing vectors when the error distribution function is either ordinary smooth or supersmooth. Our method is applied to the study conducted by UTSW medical center. The research team at UTSW collected the data of women who underwent cystoscopy fulguration for recurrent urinary tract …


Inverse Problems And Forward Propagation Of Optical Flow, John Montalbo Aug 2020

Inverse Problems And Forward Propagation Of Optical Flow, John Montalbo

Mathematics Dissertations - Archive

Optical flow is a concept originally introduced in computer vision that quantifies, and aids in the presentation of, motion (flow field) between two or more images. In essence, it is a solution of an inverse problem recovering a vector field between images through optimization techniques. This work studies the possibility of using optical flow and various techniques of forward propagation of the recovered flow field for a pair of image processing tasks in magnetic resonance imaging (MRI). It is shown that the proposed framework can be efficient in approximating missing image layers, as well as in generation of deliberately modified …


Some Examples Of The Liouville Integrability Of The Banded Toda Flows, Zachary Youmans Aug 2020

Some Examples Of The Liouville Integrability Of The Banded Toda Flows, Zachary Youmans

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Toda lattice is a famous integrable system studied by Toda in the 1960s. One can study the Toda lattice using a matrix representation of the system. Previous results have shown that this matrix of dimension n with 1 band and n‚àí1 bands is Liouville integrable. In this paper, we lay the foundation for proving the general case of the Toda lattice, where we consider the matrix representation with dimension n and a partially filled lower triangular part. We call this the banded Toda flow. The main theorem is that the banded Toda flow up to dimension 10 is …


Likelihood Inference For Flexible Cure Rate Models In The Context Of Infectious Diseases With Multiple Exposures, Zachry Joseph Engel Aug 2020

Likelihood Inference For Flexible Cure Rate Models In The Context Of Infectious Diseases With Multiple Exposures, Zachry Joseph Engel

Mathematics Dissertations - Archive

Cure rate models are mostly used to study data arising from cancer clinical trials. Its use in the context of infectious diseases has not been explored well. In 2007, Tournoud and Ecochard rst proposed a mechanistic formulation of cure rate model in the context of infectious diseases with multiple exposures to infection. However, they assumed a simple Poisson distribution to capture the unobserved number of pathogens at each exposure time. In this thesis, we propose a new exible cure rate model to study infectious diseases with discrete multiple exposures to infection. This new model uses the Conway-Maxwell Poisson (COM-Poisson) distribution …


Faktor Yang Mempengaruhi Kebolehan Perwakilan Ikonik Dan Simbolik Murid Tahun Empat Dalam Nombor Pecahan Di Sekolah Jenis Kebangsaan Cina, Wee Pu Lim Aug 2020

Faktor Yang Mempengaruhi Kebolehan Perwakilan Ikonik Dan Simbolik Murid Tahun Empat Dalam Nombor Pecahan Di Sekolah Jenis Kebangsaan Cina, Wee Pu Lim

Student Works (2020-2029)

Perwakilan matematik telah mula diberi perhatian lalu menjadi salah satu proses utama yang perlu dikuasai oleh murid. Hal ini kerana perwakilan merupakan satu elemen baharu dalam Kurikulum Standard Sekolah Rendah (KSSR). Kajian ini bertujuan untuk menentukan sama ada faktor jantina murid dan tahap pencapaian matematik murid mempengaruhi kebolehan murid tahun empat dalam perwakilan ikonik dan simbolik tentang nombor pecahan serta interaksi antara kedua-dua faktor tersebut. Untuk menjawab tiga soalan kajian ini, reka bentuk kajian perbandingan punca dan kajian faktorial telah digunakan. 596 orang murid tahun 4 (293 lelaki, 303 perempuan) daripada 5 buah sekolah dengan menggunakan pensampelan kluster dua tahap …


Math Active Learning Lab: Math 103 College Algebra Notebook, Gwennie Byron, Department Of Mathematics, University Of North Dakota Aug 2020

Math Active Learning Lab: Math 103 College Algebra Notebook, Gwennie Byron, Department Of Mathematics, University Of North Dakota

Open Educational Resources

This course notebook has been designed for students of Math 103 (College Algebra) at the University of North Dakota. It has been designed to help you get the most out of the ALEKS resources and your time.

  • Topics in the Notebook are organized by weekly learning module.
  • Space for notes from ALEKS learning pages, e-book and videos directs you to essential concepts.
  • Examples and “You Try It” problems have been carefully chosen to help you focus on these essential concepts.
  • Completed Notebook is an invaluable tool when studying for exams.


Bounds For The Number Of Independent And Dominating Sets In Trees, Daniel K. Arabia Aug 2020

Bounds For The Number Of Independent And Dominating Sets In Trees, Daniel K. Arabia

Theses, Dissertations and Culminating Projects

In this work, we investigate bounds on the number of independent sets in a graph and its complement, along with the corresponding question for number of dominating sets. Nordhaus and Gaddum gave bounds on χ(G)+χ(G) and χ(G) χ(G), where G is any graph on n vertices and χ(G) is the chromatic number of G. Nordhaus-Gaddum- type inequalities have been studied for many other graph invariants. In this work, we concentrate on i(G), the number of independent sets in G, and ∂(G), the number of dominating sets in G. We focus our attention on Nordhaus-Gaddum-type inequalities over trees on a fixed …


A Community Of Learning In An Elementary School Mathematics Classroom, Megan Louise Roeder Aug 2020

A Community Of Learning In An Elementary School Mathematics Classroom, Megan Louise Roeder

Theses, Dissertations and Culminating Projects

The goal of this study was to investigate opportunities for cultivating a community of learning in an elementary school mathematics classroom using four guiding principles for productive disciplinary engagement. A community of learning involves teachers and students participating equally in negotiating, sharing, and producing knowledge as co-learners, coteachers, and co-collaborators in the classroom. Characteristics of a community of learning align with effective teaching and learning practices described by national governing bodies and researchers in the field of mathematics education. The essence of a community of learning is beneficial in an elementary mathematics classroom because it invokes deep learning about disciplinary …


The Role Of Covariational Reasoning In Pre-Service Teachers’ Meanings For Quadratic And Exponential Relationships, Madhavi Vishnubhotla Aug 2020

The Role Of Covariational Reasoning In Pre-Service Teachers’ Meanings For Quadratic And Exponential Relationships, Madhavi Vishnubhotla

Theses, Dissertations and Culminating Projects

Researchers have indicated that students have difficulties recognizing quadratic and exponential change and do not maintain productive meanings for these relationships. Other researchers have documented that students are capable of developing productive meanings for mathematical ideas via covariational reasoning. This dissertation reports the results of an investigation into ways in which preservice teachers can leverage covariational reasoning to develop meanings for quadratic and exponential relationships. I collected data by engaging two preservice teachers in semi-structured clinical interviews and a semester long teaching experiment. My analyses reveal that whereas in the pre-interviews, the participants did not have meanings that supported differentiating …


Optimizing L1 Loss Regularizer And Its Application To Eeg Inverse Problem, Kiran Kumar Mainali Aug 2020

Optimizing L1 Loss Regularizer And Its Application To Eeg Inverse Problem, Kiran Kumar Mainali

Mathematics Dissertations - Archive

Sparse reconstruction occurs frequently in science and engineering and real-world applications, including statistics, finance, imaging, biological system, compressed sensing, and, today more than ever, machine learning and data science in general. Mathematically, they are often modeled as l1-minimization problems. There are a number of existing numerical methods that can efficiently solve such l1-minimization problems, such as Alternating Direction Methods of Multipliers (ADMM), Fast Iterative Shrinkage Thresholding Algorithm (FISTA), and Homotopy algorithm. In this dissertation, we will introduce a special type of l1-minimization problem called the Sylvester Least Absolute Shrinkage and Selection Operator (SLASSO) problem. In theory, an SLASSO problem can …


Mathematical Modeling Of Scavengers And Zebras On The African Savanna With Disease Dynamics, Crystal Dawn Mackey Aug 2020

Mathematical Modeling Of Scavengers And Zebras On The African Savanna With Disease Dynamics, Crystal Dawn Mackey

Mathematics Dissertations - Archive

The purpose of this dissertation is to use mathematical models to see how anthrax in the zebra population in Etosha National Park (ENP) interacts with scavenger populations and disease dynamics. First, we study if scavengers can save zebras from anthrax. Then we introduce a disease in the jackal population to see if anthrax in zebras can help propagate rabies in jackals. Finally, the last two models we develop describe the interaction between competing scavengers: jackals and vultures, with exploitative and interference competition. ENP is home to many different animals such as lions, jackals, hyenas, zebras, elephants, etc. Each year grazing …


Optimal Bandwidth Selection For Deconvoluted Kernel Density Estimation Using Bootstrap Method, Souad Sosa Aug 2020

Optimal Bandwidth Selection For Deconvoluted Kernel Density Estimation Using Bootstrap Method, Souad Sosa

Mathematics Dissertations - Archive

To estimate an unknown density when observed measurements are from the convolution model contaminated by additive measurement errors, Stefanski and Carroll (1990) proposed using Fourier inversion on the product of Fourier transform of a kernel function and the characteristic function of the error variable. One important element in constructing such a density estimator is the bandwidth. The goal of this research is to establish an optimal bandwidth so that the mean integrated squared error of the estimator is minimized. The bootstrap method is used to accomplish this goal. The simulation results show that the estimated optimal bandwidths provide adequate estimation …


Inverse Problems For Polynomial And Rational Matrices, Richard Allen Hollister Aug 2020

Inverse Problems For Polynomial And Rational Matrices, Richard Allen Hollister

Dissertations

Inverse problems have long been studied in mathematics not only because there are many applications in science and engineering, but also because they yield new insight into the beauty of mathematics. Central to the subject of linear algebra is the eigenvalue problem: given a matrix, and its eigenvalues (numerical invariants). Eigenvalue problems play a key role in almost every field of scientific endeavor from calculating the vibrational modes of a molecule to modeling the spread of an infectious disease, and so have been studied extensively since the time of Euler in the 18th century.

If a typical matrix eigenvalue problem …


Math Active Learning Lab: Math 107 Precalculus Notebook, Gwennie Byron, Department Of Mathematics, University Of North Dakota Aug 2020

Math Active Learning Lab: Math 107 Precalculus Notebook, Gwennie Byron, Department Of Mathematics, University Of North Dakota

Open Educational Resources

This course notebook has been designed for students of Math 107 (Precalculus) at the University of North Dakota. It has been designed to help you get the most out of the ALEKS resources and your time.

  • Topics in the Notebook are organized by weekly learning module.
  • Space for notes from ALEKS learning pages, e-book and videos directs you to essential concepts.
  • Examples and “You Try It” problems have been carefully chosen to help you focus on these essential concepts.
  • Completed Notebook is an invaluable tool when studying for exams.


Math Active Learning Lab: Math 98 Notebook, Gwennie Byron, Michele Iiams, Department Of Mathematics, University Of North Dakota Aug 2020

Math Active Learning Lab: Math 98 Notebook, Gwennie Byron, Michele Iiams, Department Of Mathematics, University Of North Dakota

Open Educational Resources

This course notebook has been designed for students of Math 98 (Intermediate Algebra) at the University of North Dakota. It has been designed to help you get the most out of the ALEKS resources and your time.

  • Topics in the Notebook are organized by weekly learning module.
  • Space for notes from ALEKS learning pages, e-book and videos directs you to essential concepts.
  • Examples and “You Try It” problems have been carefully chosen to help you focus on these essential concepts.
  • Completed Notebook is an invaluable tool when studying for exams.


Analyzing Network Topology For Ddos Mitigation Using The Abelian Sandpile Model, Bhavana Panchumarthi, Monroe Ame Stephenson Aug 2020

Analyzing Network Topology For Ddos Mitigation Using The Abelian Sandpile Model, Bhavana Panchumarthi, Monroe Ame Stephenson

altREU Projects

A Distributed Denial of Service (DDoS) is a cyber attack, which is capable of triggering a cascading failure in the victim network. While DDoS attacks come in different forms, their general goal is to make a network's service unavailable to its users. A common, but risky, countermeasure is to blackhole or null route the source, or the attacked destination. When a server becomes a blackhole, or referred to as the sink in the paper, the data that is assigned to it "disappears" or gets deleted. Our research shows how mathematical modeling can propose an alternative blackholing strategy that could improve …


Trisections Of Flat Surface Bundles Over Surfaces, Marla Williams Aug 2020

Trisections Of Flat Surface Bundles Over Surfaces, Marla Williams

Department of Mathematics: Dissertations, Theses, and Student Research

A trisection of a smooth 4-manifold is a decomposition into three simple pieces with nice intersection properties. Work by Gay and Kirby shows that every smooth, connected, orientable 4-manifold can be trisected. Natural problems in trisection theory are to exhibit trisections of certain classes of 4-manifolds and to determine the minimal trisection genus of a particular 4-manifold.

Let $\Sigma_g$ denote the closed, connected, orientable surface of genus $g$. In this thesis, we show that the direct product $\Sigma_g\times\Sigma_h$ has a $((2g+1)(2h+1)+1;2g+2h)$-trisection, and that these parameters are minimal. We provide a description of the trisection, and an algorithm to generate a …


Complete Integrability And Discretization Of Euler Top And Manakov Top, Austin Marstaller Aug 2020

Complete Integrability And Discretization Of Euler Top And Manakov Top, Austin Marstaller

Theses and Dissertations

The Euler top is a completely integrable system with physical system implications and the Manakov top is its four-dimensional extension. We are concerned about their complete integrability and the preservation of this property under a specific discretization known as the Hirota-Kimura Discretization. Surprisingly, it is not guaranteed that under any discretization the conserved quantities are preserved and therefore they must be discovered. In this work we construct the Poisson bracket and Lax pair for each system and provide the Lie algebra background needed to do such such constructions.


The Period Of The Coefficients Of The Gaussian Polynomial[N+33], Arturo J. Martinez Aug 2020

The Period Of The Coefficients Of The Gaussian Polynomial[N+33], Arturo J. Martinez

Theses and Dissertations

Definition 1. For any N, the central coefficient(s) of [N+33] is denoted by C0(N) and the coefficient that is x ''away" from the central coefficient(s) of [N+33] is denoted by Cx(N).

In [1] the following result is proved:

Theorem 2. The central coefficient(s) of the Gaussian polynomial [N+33] are described by the generating function

[Special characters omitted]

This generating function has period 4.

The main goal of this thesis is to generalize Theorem 0.2 by way of proving the following conjecture:

Conjecture 3. For any x the …


Decompositions Of The Complete Mixed Graph By Mixed Stars, Chance Culver Aug 2020

Decompositions Of The Complete Mixed Graph By Mixed Stars, Chance Culver

Electronic Theses and Dissertations

In the study of mixed graphs, a common question is: What are the necessary and suffcient conditions for the existence of a decomposition of the complete mixed graph into isomorphic copies of a given mixed graph? Since the complete mixed graph has twice as many arcs as edges, then an obvious necessary condition is that the isomorphic copies have twice as many arcs as edges. We will prove necessary and suffcient conditions for the existence of a decomposition of the complete mixed graphs into mixed stars with two edges and four arcs. We also consider some special cases of decompositions …


Article The Singular Value Expansion For Arbitrary Bounded Linear Operators, Daniel K. Crane, Mark S. Gockenbach Aug 2020

Article The Singular Value Expansion For Arbitrary Bounded Linear Operators, Daniel K. Crane, Mark S. Gockenbach

Michigan Tech Publications, Part 1

The singular value decomposition (SVD) is a basic tool for analyzing matrices. Regarding a general matrix as defining a linear operator and choosing appropriate orthonormal bases for the domain and co-domain allows the operator to be represented as multiplication by a diagonal matrix. It is well known that the SVD extends naturally to a compact linear operator mapping one Hilbert space to another; the resulting representation is known as the singular value expansion (SVE). It is less well known that a general bounded linear operator defined on Hilbert spaces also has a singular value expansion. This SVE allows a simple …


Embedding Parallelohedra Into Primitive Cubic Networks And Structural Automata Description, Mikhail M. Bouniaev, Sergey V. Krivovichev Aug 2020

Embedding Parallelohedra Into Primitive Cubic Networks And Structural Automata Description, Mikhail M. Bouniaev, Sergey V. Krivovichev

School of Mathematical & Statistical Sciences Faculty Publications

The main goal of the paper is to contribute to the agenda of developing an algorithmic model for crystallization and measuring the complexity of crystals by constructing embeddings of 3D parallelohedra into a primitive cubic network (pcu net). It is proved that any parallelohedron P as well as tiling by P, except the rhombic dodecahedron, can be embedded into the 3D pcu net. It is proved that for the rhombic dodecahedron embedding into the 3D pcu net does not exist; however, embedding into the 4D pcu net exists. The question of how many ways the embedding of a parallelohedron can …


Learning Dynamics From Large Biological Data Sets: Machine Learning Meets Systems Biology, William Gilpin, Yitong Huang, Daniel B. Forger Aug 2020

Learning Dynamics From Large Biological Data Sets: Machine Learning Meets Systems Biology, William Gilpin, Yitong Huang, Daniel B. Forger

Mathematics Sciences: Faculty Publications

In the past few decades, mathematical models based on dynamical systems theory have provided new insight into diverse biological systems. In this review, we ask whether the recent success of machine learning techniques for large-scale biological data analysis provides a complementary or competing approach to more traditional modeling approaches. Recent applications of machine learning to the problem of learning biological dynamics in diverse systems range from neuroscience to animal behavior. We compare the underlying mechanisms and limitations of traditional dynamical models with those of machine learning models. We highlight the unique role that traditional modeling has played in providing predictive …


Analyzing The Von Neumann Entropy Of Contact Networks, Thomas J. Brower Aug 2020

Analyzing The Von Neumann Entropy Of Contact Networks, Thomas J. Brower

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

When modeling the spread of disease, ecologists use ecological or contact networks to model how species interact with their environment and one another. The structure of these networks can vary widely depending on the study, where the nodes of a network can be defined as individuals, groups, or locations among other things. With this wide range of definition and with the difficulty of collecting samples, it is difficult to capture every factor of every population. Thus ecologists are limited to creating smaller networks that both fit their budget as well as what is reasonable within the population of interest. With …


Methods In Modeling Wildlife Disease From Model Selection To Parameterization With Multi-Scale Data, Ian Mcgahan Aug 2020

Methods In Modeling Wildlife Disease From Model Selection To Parameterization With Multi-Scale Data, Ian Mcgahan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effects of emerging wildlife diseases are global and profound, resulting in loss of human life, economic and agricultural impacts, declines in wildlife populations, and ecological disturbance. The spread of wildlife diseases can be viewed as the result of two simultaneous processes: spatial spread of wildlife populations and disease spread through a population. For many diseases these processes happen at different timescales, which is reflected in available data. These data come in two flavors: high-frequency, high-resolution telemetry data (e.g. GPS collar) and low-frequency, low-resolution presence-absence disease data. The multi-scale nature of these data makes analysis of such systems challenging. Mathematical …