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Full-Text Articles in Physical Sciences and Mathematics

A Class Of Transformations Of A Quadratic Integral Generating Dynamical Systems, Paul Bracken Nov 2017

A Class Of Transformations Of A Quadratic Integral Generating Dynamical Systems, Paul Bracken

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

A class of transformation is investigated which maps a quadratic integral back to its original form but under a redefinition of free parameters. When this process is iterated, a dynamical system is generated in the form of recursive sequences which involve the parameters of the integrand.

The creation of this dynamical system and some of its convergence properties are investigated.

MR3724632


A Geometric Formulation Of Lax Integrability For Nonlinear Equationsin Two Independent Variables, Paul Bracken Nov 2017

A Geometric Formulation Of Lax Integrability For Nonlinear Equationsin Two Independent Variables, Paul Bracken

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

A geometric formulation of Lax integrability is introduced which makes use of a Pfaffan formulation of Lax integrability. The Frobenius theorem gives a necessary and suffcient condition for the complete integrability of a distribution, and provides a powerful way to study nonlinear evolution equations. This permits an examination of the relation between complete integrability and Lax integrability. The prolongation method is formulated in this context and gauge transformations can be examined in terms of differential forms as well as the Frobenius theorem.


Yang Mills Theories, Paul Bracken Nov 2017

Yang Mills Theories, Paul Bracken

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

Yang-Mills gauge theories have become an important way in which to describe matter at a fundamental level. This book explores some of the aspects of their structure, quantization applications and formalism in detail. The subject matter is approached from a number of different points of view. The path integral technique is used to study and quantize the theory. Some solvable low dimensional models are introduced as well.


On The Finite W-Algebra For The Lie Superalgebra Q(N) In The Non-Regular Case, Elena Poletaeva, Vera Serganova Nov 2017

On The Finite W-Algebra For The Lie Superalgebra Q(N) In The Non-Regular Case, Elena Poletaeva, Vera Serganova

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

In this paper, we study the finite W-algebra for the queer Lie superalgebra Q(N) associated with the non-regular even nilpotent coadjoint orbits in the case when N = nl, and the corresponding nilpotent element has Jordan blocks each of size l. We prove that this finite W-algebra is isomorphic to a quotient of the super-Yangian of Q(n).


Multi-Type Branching Processes Modeling Of Nosocomial Epidemics, Zeinab Mohamed, Tamer Oraby Oct 2017

Multi-Type Branching Processes Modeling Of Nosocomial Epidemics, Zeinab Mohamed, Tamer Oraby

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

Nosocomial epidemics are infectious diseases which spread among different types of susceptible individuals in a health-care facility. To model this type of epidemics, we use a multi-type branching process with a multivariate negative binomial offspring distribution. In particular, we estimate the basic reproduction number R0 and study its relationship with the parameters of the offspring distribution. in case of a single-type epidemic, we investigate the effect of contact tracing on the estimates for R0.


Cybersecurity: Time Series Predictive Modeling Of Vulnerabilities Of Desktop Operating System Using Linear And Non-Linear Approach, Nawa Raj Pokhrel, Hansapani Rodrigo, Chris P. Tsokos Oct 2017

Cybersecurity: Time Series Predictive Modeling Of Vulnerabilities Of Desktop Operating System Using Linear And Non-Linear Approach, Nawa Raj Pokhrel, Hansapani Rodrigo, Chris P. Tsokos

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

Vulnerability forecasting models help us to predict the number of vulnerabilities that may occur in the future for a given Operating System (OS). There exist few models that focus on quantifying future vulnerabilities without consideration of trend, level, seasonality and non linear components of vulnerabilities. Unlike traditional ones, we propose a vulnerability analytic prediction model based on linear and non-linear approaches via time series analysis. We have developed the models based on Auto Regressive Moving Average (ARIMA), Artificial Neural Network (ANN), and Support Vector Machine (SVM) settings. The best model which provides the minimum error rate is selected for prediction …


Applications Of The Lichnerowicz Laplacian To Stress Energy Tensors, Paul Bracken Sep 2017

Applications Of The Lichnerowicz Laplacian To Stress Energy Tensors, Paul Bracken

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

A generalization of the Laplacian for p-forms to arbitrary tensors due to Lichnerowicz will be applied to a 2-tensor which has physical applications. It is natural to associate a divergencefree symmetric 2-tensor to a critical point of a specific variational problem and it is this 2-tensor that is studied. Numerous results are obtained for the stress-energy tensor, such as its divergence and Laplacian. A remarkable integral formula involving a symmetric 2-tensor and a conformal vector field is obtained as well


Hankel Partial Contraction, Contractive Completion, Moore-Penrose Inverse, Extremal Case, Manuel A. Villarreal Jr. Aug 2017

Hankel Partial Contraction, Contractive Completion, Moore-Penrose Inverse, Extremal Case, Manuel A. Villarreal Jr.

Theses and Dissertations

In this article we find concrete necessary and sufficient conditions for the existence of contractive completions of Hankel partial contractions of size 3x3 non-extremal case.


Assessment Of The Effects Of Azimuthal Mode Number Perturbations Upon The Implosion Processes Of Fluids In Cylinders, Michael R. Lindstrom Jun 2017

Assessment Of The Effects Of Azimuthal Mode Number Perturbations Upon The Implosion Processes Of Fluids In Cylinders, Michael R. Lindstrom

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

Highlights

  • Implosion instabilities are studied by linearizing about a symmetric implosion.

  • This suggests azimuthal instabilities decrease with time and mode number.

  • Numerics capture the delta functions from linearized solutions of conservation laws.

  • The mass of these delta functions is used to estimate perturbations in shock fronts.

  • The linear Klein–Gordon equation in one dimension is solved via formal asymptotics.

Abstract

Fluid instabilities arise in a variety of contexts and are often unwanted results of engineering imperfections. In one particular model for a magnetized target fusion reactor, a pressure wave is propagated in a cylindrical annulus comprised of a dense fluid before …


Frequency Of Nonalcoholic Fatty Liver Disease And Subclinical Atherosclerosis Among Young Mexican Americans, Clarence Gill, Kristina Vatcheva, Jen-Jung Pan, Beverly Smulevitz, David D. Mcpherson, Michael Fallon, Joseph B. Mccormick, Susan P. Fisher-Hoch, Susan T. Laing Jun 2017

Frequency Of Nonalcoholic Fatty Liver Disease And Subclinical Atherosclerosis Among Young Mexican Americans, Clarence Gill, Kristina Vatcheva, Jen-Jung Pan, Beverly Smulevitz, David D. Mcpherson, Michael Fallon, Joseph B. Mccormick, Susan P. Fisher-Hoch, Susan T. Laing

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

Non-alcoholic fatty liver disease (NAFLD) is considered the hepatic manifestation of the metabolic syndrome, whose criteria are risk factors for atherosclerotic cardiovascular disease. We aimed to evaluate the prevalence of NAFLD, its association with subclinical atherosclerosis, and factors that may account for this association in Mexican Americans. In a population based cross-sectional sample drawn from the Cameron County Hispanic Cohort in Texas, carotid intima media thickness (cIMT), an indicator of subclinical atherosclerosis, was measured. Abnormal carotid ultrasound study was defined as mean cIMT >75th percentile for age and gender and/or plaque presence. NAFLD was defined as steatosis by ultrasound in …


Investigating The Mathematical Dispositions And Self-Efficacy For Teaching Mathematics Of Preservice Teachers, Jasmine M. Cruz May 2017

Investigating The Mathematical Dispositions And Self-Efficacy For Teaching Mathematics Of Preservice Teachers, Jasmine M. Cruz

Theses and Dissertations

The study of the individual's beliefs and the role and influence they have on the individual's actions and behaviors, have long been examined and investigated by educators and psychologists. Moreover, researchers have overwhelmingly claimed and demonstrated that the beliefs held by teachers significantly influences their behavior and educational practices in the classroom. This thesis study investigates the mathematical disposition and self-efficacy for teaching mathematics of preservice teachers. The study's primary goals are to discover if there is a relationship or association between a teacher's mathematical disposition(MD) and his/her self-efficacy for teaching mathematics (SEFTM), and if there are significant differences between …


Multi-Type Branching Processes Model Of Nosocomial Epidemic, Zeinab Nageh Mohamed May 2017

Multi-Type Branching Processes Model Of Nosocomial Epidemic, Zeinab Nageh Mohamed

Theses and Dissertations

The potency of an infectious disease to spread between different types of susceptible individuals in a hospital determines the fate of controlling nosocomial epidemics. I use a multi-type branching process with a joint negative binomial offspring distribution to study nosocomial epidemics. In particular, I estimate the basic reproduction number R0 and study its relationship with the offspring distribution’s parameters at different and fixed number of generations. Also, I study the effect of contact tracing on estimates of R0.


Disease Modeling Using Fractional Differential Equations And Estimation, Daniel P. Medina May 2017

Disease Modeling Using Fractional Differential Equations And Estimation, Daniel P. Medina

Theses and Dissertations

Ordinary differential equations has been the most conventional approach when modeling spread of infectious diseases. Effective research has shown that using fractional-order differentiation can be a very useful and efficient extension for some mathematical models. In this thesis, fractional calculus is used to depict an SEIR model with a system of fractional-order differential equations. I also simulate the fractional-order SEIR using integer-order numerical methods. I also establish the estimation framework and show that it is accurately working.


Mathematical Modeling Of Mers-Cov Nosocomial Epidemic, Adriana Quiroz May 2017

Mathematical Modeling Of Mers-Cov Nosocomial Epidemic, Adriana Quiroz

Theses and Dissertations

This thesis concerns about the analysis and modeling of spread of an infectious disease inside a hospital. We begin from the basic knowledge of the simple models: SIR and SEIR, to show an appropriate understanding of the epidemic dynamic process. We consider the Middle East Respiratory Syndrome Corona Virus (MERS-CoV), in Saudi Arabia, to introduce MERS-CoV SEIR ward model by developing different systems of equations in each ward (unit). We use the Next Generation Matrix method to calculate the basic reproduction number R0. Simulations of different scenarios are done using different combination of parameters.

To model MERS-CoV we established …


Problem Book On Higher Algebra And Number Theory, Ryanto Putra May 2017

Problem Book On Higher Algebra And Number Theory, Ryanto Putra

Theses and Dissertations

This book is an attempt to provide relevant end-of-section exercises, together with their step-by-step solutions, to Dr. Zieschang's classic class notes Higher Algebra and Number Theory. It's written under the notion that active hands-on working on exercises is an important part of learning, whereby students would see the nuance and intricacies of a math concepts which they may miss from passive reading. The problems are selected here to provide background on the text, examples that illuminate the underlying theorems, as well as to fill in the gaps in the notes.


Coupled Telegraph And Sir Model Of Information And Diseases, Jose De Jesus Galarza May 2017

Coupled Telegraph And Sir Model Of Information And Diseases, Jose De Jesus Galarza

Theses and Dissertations

In this work, the effect of information propagation on disease spread and vaccination uptake through networks is studied. In this model the information reaches different people at different distances from the center of information containing the health data. We use a pair of Telegraph equations to depict the vaccine and disease information propagation on a network embedded into a straight line. The Telegraph equation is coupled with an SIR (Susceptible-Infected-Recovered) model to examine the anticipated mutual influence. Numerical simulations and stability analysis were made to study the model. We show how the propagation of information about the disease impacts the …


A New Approach To Ramanujan's Partition Congruences, Mayra C. Huerta May 2017

A New Approach To Ramanujan's Partition Congruences, Mayra C. Huerta

Theses and Dissertations

MacMahon provided Ramanujan and Hardy a table of values for p(n) with the partitions of the first 200 integers. In order to make the table readable, MacMahon grouped the entries in blocks of five. Ramanujan noticed that the last entry in each block was a multiple of 5. This motivated Ramanujan to make the following conjectures, p(5n+4) ≡ 0 (mod 5); p(7 n+5) ≡ 0 (mod 7); p(11n+6) ≡ 0 (mod 11) which he eventually proved.

The purpose of this thesis is to give new proofs for Ramanujan's partition …


Time Dependent Solution For An Incompressible Viscous Fluid Flow In A Cavity, Bishnu Parajuli May 2017

Time Dependent Solution For An Incompressible Viscous Fluid Flow In A Cavity, Bishnu Parajuli

Theses and Dissertations

The Finite Element Method is used to find the time dependent solution for an incompressible viscous fluid flow in a cavity in two dimension. The governing equations for this system are the continuity equation and the momentum equation. We use finite element method to obtain the dependent variables. Here we derive weak formulation and develop finite element model by using Galerkin Method. Then we compute velocity components of the fluid for a square cavity. The numerical results are presented.


On The Denesting Of Nested Square Roots, Eleftherios Gkioulekas Feb 2017

On The Denesting Of Nested Square Roots, Eleftherios Gkioulekas

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

We present the basic theory of denesting nested square roots, from an elementary point of view, suitable for lower level coursework. Necessary and sufficient conditions are given for direct denesting, where the nested expression is rewritten as a sum of square roots of rational numbers, and for indirect denesting, where the nested expression is rewritten as a sum of fourth-order roots of rational numbers. The theory is illustrated with several solved examples.


A Refined Approach For Non-Negative Entire Solutions Of Δ U + Up = 0 With Subcritical Sobolev Growth, John Villavert Feb 2017

A Refined Approach For Non-Negative Entire Solutions Of Δ U + Up = 0 With Subcritical Sobolev Growth, John Villavert

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

Let N≥2and 1uis a non-negative classical solution of the Lane–Emden equation, thenu≡0. The method of moving planes combined with the Kelvin transform provides an elegant proof of this theorem. A classical approach of Serrin and Zou, originally used for the Lane–Emden system, yields another proof but only in lower dimensions. Motivated by this, we further refine this approach to find an alternative proof of the Liouville type theorem in all dimensions.


Spectral Theory Of Operators On Manifolds, Paul Bracken Jan 2017

Spectral Theory Of Operators On Manifolds, Paul Bracken

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

Differential operators that are defined on a differentiable manifold can be used to study various properties of manifolds. The spectrum and eigenfunctions play a very significant role in this process. The objective of this chapter is to develop the heat equation method and to describe how it can be used to prove the Hodge Theorem. The Minakshisundaram-Pleijel parametrix and asymptotic expansion are then derived. The heat equation asymptotics can be used to give a development of the Gauss-Bonnet theorem for two-dimensional manifolds.


An Introduction To Ricci Flow For Two-Dimensional Manifolds, Paul Bracken Jan 2017

An Introduction To Ricci Flow For Two-Dimensional Manifolds, Paul Bracken

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

The study of diferentiable manifolds is a deep an extensive area of mathematics. A technique such as the study of the Ricci flow turns out to be a very useful tool in this regard. This flow is an evolution of a Riemannian metric driven by a parabolic type of partial differential equation. It has attracted great interest recently due to its important achievements in geometry such as Perelman's proof of the geometrization conjecture and Brendle-Schoen's proof of the differentiable sphere theorem. It is the purpose here to give a comprehensive introduction to the Ricci flow on manifolds of dimension two …


Electric Ion Dispersion As A New Type Of Mass Spectrometer, Michael R. Lindstrom, Iain Moyles, Kevin Ryczko Jan 2017

Electric Ion Dispersion As A New Type Of Mass Spectrometer, Michael R. Lindstrom, Iain Moyles, Kevin Ryczko

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

At the 2014 Fields-MPrime Industrial Problem Solving Workshop, PerkinElmer presented a design problem for mass spectrometry. Traditionally, mass spectrometry is done via three methods: using magnetic fields to deflect charged particles whereby different masses bend differently; using a time-of-flight procedure where particles of different mass arrive at different times at a target; and using an electric quadrupole that filters out all masses except for one very narrow band. The challenge posed in the problem was to come up with a new design for mass spectrometry that did not involve magnetic fields and where mass fractions could be measured in an …


Using Technology To Determine Factorability Or Non-Factorability Of Quadratic Algebraic Trinomials, John E. T. Bernard, Olga Ramirez, Cristina Villalobos Jan 2017

Using Technology To Determine Factorability Or Non-Factorability Of Quadratic Algebraic Trinomials, John E. T. Bernard, Olga Ramirez, Cristina Villalobos

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

This paper is aimed for mathematics educators who teach algebra, more specifically, the factoring of quadratic algebraic expressions, and who want to enhance student learning of this topic using technology in conjunction with the Middle Term Splitting Method (Donnell, 2010; MTSM 2016a; MTSM 2016b). We will use technology-based algebra and geometry connections to help determine factorability or nonfactorability of quadratic algebraic trinomials over the integers, over the real numbers, and over the complex numbers, both with clarity, certainty and with understanding by using two equations, one derived from the coefficients of the outer terms and the other from the middle …


An Intrinsic Characterization Of Bonnet Surfaces Based On A Closed Differential Ideal, Paul Bracken Jan 2017

An Intrinsic Characterization Of Bonnet Surfaces Based On A Closed Differential Ideal, Paul Bracken

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

The structure equations for a two-dimensional manifold are introduced and two results based on the Codazzi equations pertinent to the study of isometric surfaces are obtained from them. Important theorems pertaining to isometric surfaces are stated and a theorem due to Bonnet is obtained. A transformation for the connection forms is developed. It is proved that the angle of deformation must be harmonic, and that the differentials of many of the important variables generate a closed differential ideal. This implies that a coordinate system exists in which many of the variables satisfy particular ordinary differential equations, and these results can …