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

Applied Mathematics Commons

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

Mathematics

Selected Works

Institution
Keyword
Publication Year
Publication
File Type

Articles 1 - 30 of 286

Full-Text Articles in Applied Mathematics

Closed-Form Probability Distribution Of Number Of Infections At A Given Time In A Stochastic Sis Epidemic Model.Pdf, Michael Otunuga Sep 2019

Closed-Form Probability Distribution Of Number Of Infections At A Given Time In A Stochastic Sis Epidemic Model.Pdf, Michael Otunuga

Olusegun Michael Otunuga

We study the effects of external fluctuations in the transmission rate of certain diseases and how these affect the distribution of the number of infected individuals over time. To do this, we introduce random noise in the transmission rate in a deterministic SIS model and study how the number of infections changes over time. The objective of this work is to derive and analyze the closed form probability distribution of the number of infections at a given time in the resulting stochastic SIS epidemic model. Using the Fokker-Planck equation, we reduce the differential equation governing the number of infections to …


Finding Positive Solutions Of Boundary Value Dynamic Equations On Time Scale, Olusegun Michael Otunuga Feb 2019

Finding Positive Solutions Of Boundary Value Dynamic Equations On Time Scale, Olusegun Michael Otunuga

Olusegun Michael Otunuga

This thesis is on the study of dynamic equations on time scale. Most often, the derivatives and anti-derivatives of functions are taken on the domain of real numbers, which cannot be used to solve some models like insect populations that are continuous while in season and then follow a difference scheme with variable step-size. They die out in winter, while the eggs are incubating or dormant; and then they hatch in a new season, giving rise to a non overlapping population. The general idea of my thesis is to find the conditions for having a positive solution of any boundary …


Local Lagged Adapted Generalized Method Of Moments: An Innovative Estimation And Forecasting Approach And Its Applications.Pdf, Olusegun M. Otunuga Jan 2019

Local Lagged Adapted Generalized Method Of Moments: An Innovative Estimation And Forecasting Approach And Its Applications.Pdf, Olusegun M. Otunuga

Olusegun Michael Otunuga

In this work, an attempt is made to apply the Local Lagged Adapted Generalized Method of Moments (LLGMM) to estimate state and parameters in stochastic differential dynamic models. The development of LLGMM is motivated by parameter and state estimation problems in continuous-time nonlinear and non-stationary stochastic dynamic model validation problems in biological, chemical, engineering, energy commodity markets, financial, medical, physical and social sciences. The byproducts of this innovative approach (LLGMM) are the balance between model specification and model prescription of continuous-time dynamic process and the development of discrete-time interconnected dynamic model of local sample mean and variance statistic process (DTIDMLSMVSP). …


Call For Abstracts - Resrb 2019, July 8-9, Wrocław, Poland, Wojciech M. Budzianowski Dec 2018

Call For Abstracts - Resrb 2019, July 8-9, Wrocław, Poland, Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.


A Companion To The Introduction To Modern Dynamics, David D. Nolte Dec 2018

A Companion To The Introduction To Modern Dynamics, David D. Nolte

David D Nolte

A Jr/Sr Mechanics/Dynamics textbook from Oxford University Press, updating how we teach undergraduate physics majors with increased relevance for physics careers in changing times.

Additional materials, class notes and examples to go with the textbook Introduction to Modern Dynamics: Chaos, Networks, Space and Time (Oxford University Press, 2019).

The best parts of physics are the last topics that our students ever see.  These are the exciting new frontiers of nonlinear and complex systems that are at the forefront of university research and are the basis of many of our high-tech businesses.  Topics such as traffic on the World Wide Web, …


Homogenization In Perforated Domains And With Soft Inclusions, Brandon C. Russell Apr 2018

Homogenization In Perforated Domains And With Soft Inclusions, Brandon C. Russell

Brandon Russell

In this dissertation, we first provide a short introduction to qualitative homogenization of elliptic equations and systems. We collect relevant and known results regarding elliptic equations and systems with rapidly oscillating, periodic coefficients, which is the classical setting in homogenization of elliptic equations and systems. We extend several classical results to the so-called case of perforated domains and consider materials reinforced with soft inclusions. We establish quantitative H^1-convergence rates in both settings, and as a result deduce large-scale Lipschitz estimates and Liouville-type estimates for solutions to elliptic systems with rapidly oscillating, periodic, bounded, and measurable coefficients. Finally, we connect these …


The Subject Librarian Newsletter, Mathematics, Spring 2017, Sandy Avila Apr 2018

The Subject Librarian Newsletter, Mathematics, Spring 2017, Sandy Avila

Sandy Avila

No abstract provided.


Global Stability For A 2n+1 Dimensional Hiv Aids Epidemic Model With Treatments, Olusegun M. Otunuga Mar 2018

Global Stability For A 2n+1 Dimensional Hiv Aids Epidemic Model With Treatments, Olusegun M. Otunuga

Olusegun Michael Otunuga

In this work, we derive and analyze a 2n+1-dimensional deterministic differential equation modeling the transmission and treatment of HIV (Human Immunodeficiency Virus) disease. The model is extended to a stochastic differential equation by introducing noise in the transmission rate of the disease. A theoretical treatment strategy of regular HIV testing and immediate treatment with Antiretroviral Therapy (ART) is investigated in the presence and absence of noise. By defining $R_{0,n}$, $R_{t,n}$ and $\mathcal{R}_{t,n}$ as the deterministic basic reproduction number in the absence of ART treatments, deterministic basic reproduction number in the presence of ART treatments and stochastic reproduction number …


Inventing Around Edison’S Lamp Patent: The Role Of Patents In Stimulating Downstream Development And Competition, Ron D. Katznelson, John Howells Feb 2018

Inventing Around Edison’S Lamp Patent: The Role Of Patents In Stimulating Downstream Development And Competition, Ron D. Katznelson, John Howells

Ron D. Katznelson

We provide the first detailed empirical study of inventing around patent claims. The enforcement of Edison’s incandescent lamp patent in 1891-1894 stimulated a surge of patenting. Most of these later patents disclosed inventions around the Edison patent. Some of these patents introduced important new technology in their own right and became prior art for new fields, indicating that invention around patents contributes to dynamic efficiency. Contrary to widespread contemporary understanding, the Edison lamp patent did not suppress technological advance in electric lighting. The market position of General Electric (“GE”), the Edison patent-owner, weakened through the period of this patent’s enforcement.


Cara Aborsi Obat Cytotec Mentok 081901222272 Jual Obat Aborsi Di Mentok, Apotik Cytotec Dec 2017

Cara Aborsi Obat Cytotec Mentok 081901222272 Jual Obat Aborsi Di Mentok, Apotik Cytotec

Apotik Cytotec

SELAMAT DATANG DI SITUS ABORSI REAL & TERPERCAYA DI INDONESIA - JUAL OBAT ABORSI REKOMENDASI DOKTER | OBAT ABORSI PENGGUGUR KANDUNGAN 100% AMPUH - OBAT CYTOTEC ASLI CARA PALING AMAN UNTUK MENUNDA ATAU MENGGUGURKAN KANDUNGAN MULAI DARI USIA 1 2 3 4 5 6 BULAN

HUBUNGI SEGERA PEN JUAL OBAT CYTOTEC PFIZER FDA USA ORIGINAL

PHONE : 081-901-2222-72 ( WhatsApp )

BBM : 5D5E783E



Selamat Datang Di Situs Website Resmi Kami Penjualan Obat Aborsi Asli di Indonesia. Kami Adalah Penjual Obat Cytotec Yang Sangat Terpercaya Untuk Membantu Masalah Menggugurkan Kandungan Dengan …


Time Varying Parameter Estimation Scheme For A Linear Stochastic Differential Equation.Pdf, Michael Otunuga Aug 2017

Time Varying Parameter Estimation Scheme For A Linear Stochastic Differential Equation.Pdf, Michael Otunuga

Olusegun Michael Otunuga

p, li { white-space: pre-wrap; }
In this work, an attempt is made to estimate time varying parameters in a linear stochastic differential equation. By defining $m_{k}$ as the local admissible sample/data observation size at time $t_{k}$, parameters and state at time $t_{k}$ are estimated using past data on interval $[t_{k-m_{k}+1}, t_{k}]$. We show that the parameter estimates at each time $t_{k}$ converge in probability to the true value of the parameters being estimated. A numerical simulation is presented by applying the local lagged adapted generalized method of moments (LLGMM) method to the stochastic differential models governing prices …


When Cp(X) Is Domain Representable, William Fleissner, Lynne Yengulalp Mar 2017

When Cp(X) Is Domain Representable, William Fleissner, Lynne Yengulalp

Lynne Yengulalp

Let M be a metrizable group. Let G be a dense subgroup of MX . If G is domain representable, then G = MX . The following corollaries answer open questions. If X is completely regular and Cp(X) is domain representable, then X is discrete. If X is zero-dimensional, T2 , and Cp(X;D) is subcompact, then X is discrete.


Sphere Representations, Stacked Polytopes, And The Colin De Verdière Number Of A Graph, Lon Mitchell, Lynne Yengulalp Mar 2017

Sphere Representations, Stacked Polytopes, And The Colin De Verdière Number Of A Graph, Lon Mitchell, Lynne Yengulalp

Lynne Yengulalp

We prove that a k-tree can be viewed as a subgraph of a special type of (k + 1)- tree that corresponds to a stacked polytope and that these “stacked” (k + 1)-trees admit representations by orthogonal spheres in R k+1. As a result, we derive lower bounds for Colin de Verdi`ere’s µ of complements of partial k-trees and prove that µ(G) + µ(G) > |G| − 2 for all chordal G.


Coarser Connected Topologies And Non-Normality Points, Lynne Yengulalp Mar 2017

Coarser Connected Topologies And Non-Normality Points, Lynne Yengulalp

Lynne Yengulalp

We investigate two topics, coarser connected topologies and non-normality points. The motivating question in the first topic is:

Question 0.0.1. When does a space have a coarser connected topology with a nice topological property? We will discuss some results when the property is Hausdorff and prove that if X is a non-compact metric space that has weight at least c, then it has a coarser connected metrizable topology. The second topic is concerned with the following question:

Question 0.0.2. When is a point y ∈ β X\X a non-normality point of β X\X? We will discuss the question in the …


Non-Normality Points Of Β X\X, William Fleissner, Lynne Yengulalp Mar 2017

Non-Normality Points Of Β X\X, William Fleissner, Lynne Yengulalp

Lynne Yengulalp

We seek conditions implying that (β X\X) \ {y} is not normal. Our main theorem: Assume GCH and all uniform ultrafilters are regular. If X is a locally compact metrizable space without isolated points, then (β X\X) \ {y} is not normal for all y ∈ β X\X. In preparing to prove this theorem, we generalize the notions “uniform”, “regular”, and “good” from set ultrafilters to z-ultrafilters. We discuss non-normality points of the product of a discrete space and the real line. We topologically embed a nonstandard real line into the remainder of this product space.


Global Stability Of Nonlinear Stochastic Sei Epidemic Model With Fluctuations In Transmission Rate Of Disease, Olusegun M. Otunuga Jan 2017

Global Stability Of Nonlinear Stochastic Sei Epidemic Model With Fluctuations In Transmission Rate Of Disease, Olusegun M. Otunuga

Olusegun Michael Otunuga

We derive and analyze the dynamic of a stochastic SEI epidemic model for disease spread. Fluctuations in the transmission rate of the disease bring about stochasticity in model. We discuss the asymptotic stability of the infection-free equilibrium by first deriving the closed form deterministic ($R_{0}$) and stochastic ($\mathcal{R}_{0}$) basic reproductive number. Contrary to some author's remark that different diffusion rates have no effect on the stability of the disease-free equilibrium, we showed that even if no epidemic invasion occurs with respect to the deterministic version of the SEI model (that is, $R_{0}<1$), epidemic can still …


C.V. - Wojciech Budzianowski, Wojciech M. Budzianowski Jan 2017

C.V. - Wojciech Budzianowski, Wojciech M. Budzianowski

Wojciech Budzianowski

-


Renewable Energy And Sustainable Development (Resd) Group, Wojciech M. Budzianowski Jan 2017

Renewable Energy And Sustainable Development (Resd) Group, Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.


Application Of Polynomial Interpolation In The Chinese Remainder Problem, Tian-Xiao He, S. Macdonald, P. J.-S. Shiue Dec 2016

Application Of Polynomial Interpolation In The Chinese Remainder Problem, Tian-Xiao He, S. Macdonald, P. J.-S. Shiue

Tian-Xiao He

This paper presents an application of polynomial interpolation in the solution of the Chinese Remainder Problem for bother integers and polynomials.


Foundations Of Wave Phenomena, Charles G. Torre Dec 2016

Foundations Of Wave Phenomena, Charles G. Torre

Charles G. Torre

This is an undergraduate text on the mathematical foundations of wave phenomena. Version 8.2.


Computing The Optimal Path In Stochastic Dynamical Systems, Martha Bauver, Eric Forgoston, Lora Billings Aug 2016

Computing The Optimal Path In Stochastic Dynamical Systems, Martha Bauver, Eric Forgoston, Lora Billings

Lora Billings

In stochastic systems, one is often interested in finding the optimal path that maximizes the probability of escape from a metastable state or of switching between metastable states. Even for simple systems, it may be impossible to find an analytic form of the optimal path, and in high- dimensional systems, this is almost always the case. In this article, we formulate a constructive methodology that is used to compute the optimal path numerically. The method utilizes finite-time Lyapunov exponents, statistical selection criteria, and a Newton-based iterative minimizing scheme. The method is applied to four examples. The first example is a …


Computing The Optimal Path In Stochastic Dynamical Systems, Martha Bauver, Eric Forgoston, Lora Billings Aug 2016

Computing The Optimal Path In Stochastic Dynamical Systems, Martha Bauver, Eric Forgoston, Lora Billings

Eric Forgoston

In stochastic systems, one is often interested in finding the optimal path that maximizes the probability of escape from a metastable state or of switching between metastable states. Even for simple systems, it may be impossible to find an analytic form of the optimal path, and in high- dimensional systems, this is almost always the case. In this article, we formulate a constructive methodology that is used to compute the optimal path numerically. The method utilizes finite-time Lyapunov exponents, statistical selection criteria, and a Newton-based iterative minimizing scheme. The method is applied to four examples. The first example is a …


Procesy Cieplne I Aparaty (Lab), Wojciech M. Budzianowski Jan 2016

Procesy Cieplne I Aparaty (Lab), Wojciech M. Budzianowski

Wojciech Budzianowski

-


Inżynieria Chemiczna Lab., Wojciech M. Budzianowski Jan 2016

Inżynieria Chemiczna Lab., Wojciech M. Budzianowski

Wojciech Budzianowski

-


Applications Of Riordan Matrix Functions To Bernoulli And Euler Polynomials, Tian-Xiao He Dec 2015

Applications Of Riordan Matrix Functions To Bernoulli And Euler Polynomials, Tian-Xiao He

Tian-Xiao He

We dene Riordan matrix functions associated with Riordan arrays and study their algebraic properties. We also give their applications in the construction of new classes of Bernoulli and Euler polynomials and Bernoulli and Euler numbers, referred to as the duals and conjugate Bernoulli and Euler polynomials and dual and conjugate Bernoulli
and Euler numbers, respectively.


Shift Operators Defined In The Riordan Group And Their Applications, Tian-Xiao He Dec 2015

Shift Operators Defined In The Riordan Group And Their Applications, Tian-Xiao He

Tian-Xiao He

In this paper, we discuss a linear operator T dened in Riordan group R by using the upper shift matrix U and lower shift matrix UT ; namely for each R 2 R, T : R 7! URUT . Some isomorphic properties of the operator T and the structures of its range sets for dierent domains are studied. By using the operator T and the properties of Bell subgroup of R, the Riordan type Chu-Vandermonde identities and the Riordan equivalent identities of Format Last Theorem and Beal Conjecture are shown. The applications of the shift operators to the complementary Riordan …


Rene Salinas.Jpg, Rene A. Salinas Dec 2015

Rene Salinas.Jpg, Rene A. Salinas

Dr. Rene Salinas

No abstract provided.


Coarsening In High Order, Discrete, Ill-Posed Diffusion Equations, Catherine Kublik Aug 2015

Coarsening In High Order, Discrete, Ill-Posed Diffusion Equations, Catherine Kublik

Catherine Kublik

We study the discrete version of a family of ill-posed, nonlinear diffusion equations of order 2n. The fourth order (n=2) version of these equations constitutes our main motivation, as it appears prominently in image processing and computer vision literature. It was proposed by You and Kaveh as a model for denoising images while maintaining sharp object boundaries (edges). The second order equation (n=1) corresponds to another famous model from image processing, namely Perona and Malik's anisotropic diffusion, and was studied in earlier papers. The equations studied in this paper are high order analogues of the Perona-Malik equation, and like the …


Algorithms For Area Preserving Flows, Catherine Kublik, Selim Esedoglu, Jeffrey A. Fessler Aug 2015

Algorithms For Area Preserving Flows, Catherine Kublik, Selim Esedoglu, Jeffrey A. Fessler

Catherine Kublik

We propose efficient and accurate algorithms for computing certain area preserving geometric motions of curves in the plane, such as area preserving motion by curvature. These schemes are based on a new class of diffusion generated motion algorithms using signed distance functions. In particular, they alternate two very simple and fast operations, namely convolution with the Gaussian kernel and construction of the distance function, to generate the desired geometric flow in an unconditionally stable manner. We present applications of these area preserving flows to large scale simulations of coarsening.


An Implicit Interface Boundary Integral Method For Poisson’S Equation On Arbitrary Domains, Catherine Kublik, Nicolay M. Tanushev, Richard Tsai Aug 2015

An Implicit Interface Boundary Integral Method For Poisson’S Equation On Arbitrary Domains, Catherine Kublik, Nicolay M. Tanushev, Richard Tsai

Catherine Kublik

We propose a simple formulation for constructing boundary integral methods to solve Poisson’s equation on domains with smooth boundaries defined through their signed distance function. Our formulation is based on averaging a family of parameterizations of an integral equation defined on the boundary of the domain, where the integrations are carried out in the level set framework using an appropriate Jacobian. By the coarea formula, the algorithm operates in the Euclidean space and does not require any explicit parameterization of the boundaries. We present numerical results in two and three dimensions.