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Full-Text Articles in Physical Sciences and Mathematics

Extremal Results For Peg Solitaire On Graphs, Aaron D. Gray Dec 2013

Extremal Results For Peg Solitaire On Graphs, Aaron D. Gray

Electronic Theses and Dissertations

In a 2011 paper by Beeler and Hoilman, the game of peg solitaire is generalized to arbitrary boards. These boards are treated as graphs in the combinatorial sense. An open problem from that paper is to determine the minimum number of edges necessary for a graph with a fixed number of vertices to be solvable. This thesis provides new bounds on this number. It also provides necessary and sufficient conditions for two families of graphs to be solvable, along with criticality results, and the maximum number of pegs that can be left in each of the two graph families.


Mixture Of Poisson Distributions To Model Discrete Stock Price Changes., Rasitha Rangani Jayasekare Kodippuli Thanthillage Dona Aug 2013

Mixture Of Poisson Distributions To Model Discrete Stock Price Changes., Rasitha Rangani Jayasekare Kodippuli Thanthillage Dona

Electronic Theses and Dissertations

An application of a mixture of Poisson distributions is proposed to model the discrete changes in stock price based on the minimum price movement known as `tick-size'. The parameters are estimated using the Expectation-Maximization (EM) algorithm with a constant mixing probability as well as mixing probabilities which depend on order size. The model is evaluated using simulations and real data. Both the simulated and real data show reasonable estimates. Several adjustments are made to the model implementation to improve the efficiency with user written codes for the Newton Raphson algorithm and also implementing one of the most recent versions of …


Packings And Coverings Of Complete Graphs With A Hole With The 4-Cycle With A Pendant Edge, Yan Xia Aug 2013

Packings And Coverings Of Complete Graphs With A Hole With The 4-Cycle With A Pendant Edge, Yan Xia

Electronic Theses and Dissertations

In this thesis, we consider packings and coverings of various complete graphs with the 4-cycle with a pendant edge. We consider both restricted and unrestricted coverings. Necessary and sufficient conditions are given for such structures for (1) complete graphs Kv, (2) complete bipartite graphs Km,n, and (3) complete graphs with a hole K(v,w).


Loops And Their Permutation Groups, Mark Greer Jun 2013

Loops And Their Permutation Groups, Mark Greer

Electronic Theses and Dissertations

This dissertation uses the connections between loops and their associated permutation groups to study certain varieties of loops. We first define a variety of loops generalizing commutative automorphic loops and show this new variety is power associative. We show a correspondence to Bruck loops of odd order and use this correspondence to give structural results for our new variety, which in turn hold for commutative automorphic loops. Next, we study a variety of loops that generalize both Moufang and Steiner loops. We extend on known results for Moufang loops and then extend two different doubling constructions for creating Moufang and …


Very Cost Effective Partitions In Graphs, Inna Vasylieva May 2013

Very Cost Effective Partitions In Graphs, Inna Vasylieva

Electronic Theses and Dissertations

For a graph G=(V,E) and a set of vertices S, a vertex v in S is said to be very cost effective if it is adjacent to more vertices in V -S than in S.

A bipartition pi={S, V- S} is called very cost effective if both S and V- S are very cost effective sets. Not all graphs have a very cost effective bipartition, for example, the complete graphs of odd order do not. We consider several families of graphs G, including Cartesian products and cacti graphs, to determine whether G has a very cost effective bipartition.


Peg Solitaire On Trees With Diameter Four, Clayton A. Walvoort May 2013

Peg Solitaire On Trees With Diameter Four, Clayton A. Walvoort

Electronic Theses and Dissertations

In a paper by Beeler and Hoilman, the traditional game of peg solitaire is generalized to graphs in the combinatorial sense. One of the important open problems in this paper was to classify solvable trees. In this thesis, we will give necessary and sufficient conditions for the solvability for all trees with diameter four. We also give the maximum number of pegs that can be left on such a graph under the restriction that we jump whenever possible.


Restricted And Unrestricted Coverings Of Complete Bipartite Graphs With Hexagons, Wesley M. Surber May 2013

Restricted And Unrestricted Coverings Of Complete Bipartite Graphs With Hexagons, Wesley M. Surber

Electronic Theses and Dissertations

A minimal covering of a graph G with isomorphic copies of graph H is a set {H1, H2, H3, ... , Hn} where Hi is isomorphic to H, the vertex set of Hi is a subset of G, the edge set of G is a subset of the union of Hi's, and the cardinality of the union of Hi's minus G is minimum. Some studies have been made of covering the complete graph in which case an added condition of the edge set of Hi …


A Variety Of Proofs Of The Steiner-Lehmus Theorem, Sherri R. Gardner May 2013

A Variety Of Proofs Of The Steiner-Lehmus Theorem, Sherri R. Gardner

Electronic Theses and Dissertations

The Steiner-Lehmus Theorem has garnered much attention since its conception in the 1840s. A variety of proofs resulting from the posing of the theorem are still appearing today, well over 100 years later. There are some amazing similarities among these proofs, as different as they seem to be. These characteristics allow for some interesting groupings and observations.


Level Crossing Times In Mathematical Finance, Ofosuhene Osei May 2013

Level Crossing Times In Mathematical Finance, Ofosuhene Osei

Electronic Theses and Dissertations

Level crossing times and their applications in finance are of importance, given certain threshold levels that represent the "desirable" or "sell" values of a stock. In this thesis, we make use of Wald's lemmas and various deep results from renewal theory, in the context of finance, in modelling the growth of a portfolio of stocks. Several models are employed .


A Mathematical Model For Antibiotic Resistance In A Hospital Setting With A Varying Population, Edward H. Snyder May 2013

A Mathematical Model For Antibiotic Resistance In A Hospital Setting With A Varying Population, Edward H. Snyder

Electronic Theses and Dissertations

Antibiotic-resistant bacteria(ARB) is causing increased health risk and cost to society. Mathematical models have been developed to study the transmission of resistant bacteria and the efficacy of preventive measures to slow its spread within a hospital setting. The majority of these models have assumed a constant total hospital population with the admission and discharge rates being equal throughout the duration. But a typical hospital population varies from day to day and season to season. In this thesis, we apply variable admission and discharge daily rates to existing deterministic and stochastic models which examine the transmission of single and dual resistant …


Statistical Properties Of The Mc-Dagum And Related Distributions, Sasith Rajasooriya Apr 2013

Statistical Properties Of The Mc-Dagum And Related Distributions, Sasith Rajasooriya

Electronic Theses and Dissertations

In this thesis, we present a new class of distributions called Mc-Dagum distribution. This class of distributions contains several distributions such as beta-Dagum, beta-Burr III, beta-Fisk and Dagum distributions as special cases. The hazard function, reverse hazard function, moments and mean residual life function are obtained. Inequality measures, entropy and Fisher information are presented. Maximum likelihood estimates of the model parameters are given.


Variational Methods On Elastic Curves, Daniel D. Rocker Apr 2013

Variational Methods On Elastic Curves, Daniel D. Rocker

Electronic Theses and Dissertations

In this thesis we investigate elastic curves. These are curves with minimal bending energy as measured by the total squared curvature functional. We show that these can be computed by evolving curves in the direction of the negative gradient in certain Hilbert space settings. By discretizing the curves and using numerical integration, we compute approximate minimizers and display using computer graphics. We propose a conjecture based on the rotation number of a curve that predicts the critical point curves that minimize bending energy.


Approximate Similarity Reduction, Rui Zhang Apr 2013

Approximate Similarity Reduction, Rui Zhang

Electronic Theses and Dissertations

The nonlinear K (n;1) equation with damping is investigated via the approximate homotopy symmetry method and approximate homotopy direct method. The approximate homotopy symmetry and homotopy similarity reduction equations of different orders are derived and the corresponding homotopy series reduction solutionsare obtained. As a result, the formal coincidence for both methods is displayed.


Partially Integrable Pt-Symmetric Hierarchies Of Some Canonical Nonlinear Partial Differential Equations, Keri Pecora Jan 2013

Partially Integrable Pt-Symmetric Hierarchies Of Some Canonical Nonlinear Partial Differential Equations, Keri Pecora

Electronic Theses and Dissertations

In this dissertation, we generalize the work of Bender and co-workers to derive new partially-integrable hierarchies of various PT -symmetric, nonlinear partial differential equations. The possible integrable members are identified employing the Painlev´e Test, a necessary but not sufficient integrability condition, and are indexed by the integer n, corresponding to the negative of the order of the dominant pole in the singular part of the Painlev´e expansion for the solution. For the PT -symmetric Korteweg-de Vries (KdV) equation, as with some other hierarchies, the first or n = 1 equation fails the test, the n = 2 member corresponds to …


Numerical Simulations For The Flow Of Rocket Exhaust Through A Granular Medium, Kristina Kraakmo Jan 2013

Numerical Simulations For The Flow Of Rocket Exhaust Through A Granular Medium, Kristina Kraakmo

Electronic Theses and Dissertations

Physical lab experiments have shown that the pressure caused by an impinging jet on a granular bed has the potential to form craters. This poses a danger to landing success and nearby spacecraft for future rocket missions. Current numerical simulations for this process do not accurately reproduce experimental results. Our goal is to produce improved simulations to more accurately and effi- ciently model the changes in pressure as gas flows through a porous medium. A two-dimensional model in space known as the nonlinear Porous Medium Equation as it is derived from Darcy’s law is used. An Alternating-Direction Implicit (ADI) temporal …


Smooth And Non-Smooth Traveling Wave Solutions Of Some Generalized Camassa-Holm Equations, Taslima Rehman Jan 2013

Smooth And Non-Smooth Traveling Wave Solutions Of Some Generalized Camassa-Holm Equations, Taslima Rehman

Electronic Theses and Dissertations

In this thesis we employ two recent analytical approaches to investigate the possible classes of traveling wave solutions of some members of recently derived integrable family of generalized Camassa-Holm (GCH) equations. In the first part, a novel application of phase-plane analysis is employed to analyze the singular traveling wave equations of four GCH equations, i.e. the possible non-smooth peakon, cuspon and compacton solutions. Two of the GCH equations do no support singular traveling waves. We generalize an existing theorem to establish the existence of peakon solutions of the third GCH equation. This equation is found to also support four segmented, …


Spectrally Uniform Frames And Spectrally Optimal Dual Frames, Saliha Pehlivan Jan 2013

Spectrally Uniform Frames And Spectrally Optimal Dual Frames, Saliha Pehlivan

Electronic Theses and Dissertations

Frames have been useful in signal transmission due to the built in redundancy. In recent years, the erasure problem in data transmission has been the focus of considerable research in the case the error estimate is measured by operator (or matrix) norm. Sample results include the characterization of one-erasure optimal Parseval frames, the connection between two-erasure optimal Parseval frames and equiangular frames, and some characterization of optimal dual frames. If iterations are allowed in the reconstruction process of the signal vector, then spectral radius measurement for the error operators is more appropriate then the operator norm measurement. We obtain a …


Modified Pal Interpolation And Sampling Bilevel Signals With Finite Rate Of Innovation, Gayatri Ramesh Jan 2013

Modified Pal Interpolation And Sampling Bilevel Signals With Finite Rate Of Innovation, Gayatri Ramesh

Electronic Theses and Dissertations

Sampling and interpolation are two important topics in signal processing. Signal processing is a vast field of study that deals with analysis and operations of signals such as sounds, images, sensor data, telecommunications and so on. It also utilizes many mathematical theories such as approximation theory, analysis and wavelets. This dissertation is divided into two chapters: Modified Pal´ Interpolation and Sampling Bilevel Signals with Finite Rate of Innovation. In the first chapter, we introduce a new interpolation process, the modified Pal interpolation, based on papers by P ´ al, J ´ oo´ and Szabo, and we establish the existence and …


Can One Hear...? An Exploration Into Inverse Eigenvalue Problems Related To Musical Instruments, Christine Adams Jan 2013

Can One Hear...? An Exploration Into Inverse Eigenvalue Problems Related To Musical Instruments, Christine Adams

Electronic Theses and Dissertations

The central theme of this thesis deals with problems related to the question, “Can one hear the shape of a drum?” first posed formally by Mark Kac in 1966. More precisely, can one determine the shape of a membrane with fixed boundary from the spectrum of the associated differential operator? For this paper, Kac received both the Lester Ford Award and the Chauvant Prize of the Mathematical Association of America. This problem has received a great deal of attention in the past forty years and has led to similar questions in completely different contexts such as “Can one hear the …


Curvelets And The Radon Transform, Jill Dickerson Jan 2013

Curvelets And The Radon Transform, Jill Dickerson

Electronic Theses and Dissertations

Computed Tomography (CT) is the standard in medical imaging field. In this study, we look at the curvelet transform in an attempt to use it as a basis for representing a function. In doing so, we seek a way to reconstruct a function from the Radon data that may produce clearer results. Using curvelet decomposition, any known function can be represented as a sum of curvelets with corresponding coefficients. It can be shown that these corresponding coefficients can be found using the Radon data, even if the function is unknown. The use of curvelets has the potential to solve partial …


Optimization Problem In Single Period Markets, Tian Jiang Jan 2013

Optimization Problem In Single Period Markets, Tian Jiang

Electronic Theses and Dissertations

There had been a number of researches that investigated on the security market without transaction costs. The focus of this research is in the area that when the security market with transaction costs is fair and in such fair market how one chooses a suitable portfolio to optimize the financial goal. The research approach adopted in this thesis includes linear algebra and elementary probability. The thesis provides evidence that we can maximize expected utility function to achieve our goal (maximize expected return under certain risk tolerance). The main conclusions drawn from this study are under certain conditions the security market …


Nonparametric And Empirical Bayes Estimation Methods, Rida Benhaddou Jan 2013

Nonparametric And Empirical Bayes Estimation Methods, Rida Benhaddou

Electronic Theses and Dissertations

In the present dissertation, we investigate two different nonparametric models; empirical Bayes model and functional deconvolution model. In the case of the nonparametric empirical Bayes estimation, we carried out a complete minimax study. In particular, we derive minimax lower bounds for the risk of the nonparametric empirical Bayes estimator for a general conditional distribution. This result has never been obtained previously. In order to attain optimal convergence rates, we use a wavelet series based empirical Bayes estimator constructed in Pensky and Alotaibi (2005). We propose an adaptive version of this estimator using Lepski’s method and show that the estimator attains …


Valuation Of Over-The-Counter (Otc) Derivatives With Collateralization, Leon Guerrero Jan 2013

Valuation Of Over-The-Counter (Otc) Derivatives With Collateralization, Leon Guerrero

Electronic Theses and Dissertations

Collateralization in over-the-counter (OTC) derivatives markets has grown rapidly over the past decade, and even faster in the past few years, due to the impact of the recent financial crisis and the particularly important attention to the counterparty credit risk in derivatives contracts. The addition of collateralization to such contracts significantly reduces the counterparty credit risk and allows to offset liabilities in case of default. We study the problem of valuation of OTC derivatives with payoff in a single currency and with single underlying asset for the cases of zero, partial, and perfect collateralization. We assume the derivative is traded …


Dynamical Invariants And The Fluid Impulse In Plasma Models, Martin Michalak Jan 2013

Dynamical Invariants And The Fluid Impulse In Plasma Models, Martin Michalak

Electronic Theses and Dissertations

Much progress has been made in understanding of plasmas through the use of the MHD equations and newer models such as Hall MHD and electron MHD. As with most equations of fluid behavior, these equations are nonlinear, and no general solutions can be found. The use of invariant structures allows limited predictions of fluid behavior without requiring a full solution of the underlying equations. The use of gauge transformation can allow the creation of new invariants, while differential geometry offers useful tools for constructing additional invariants from those that are already known. Using these techniques, new geometric, integral and topological …


Extensions Of S-Spaces, Bernd Losert Jan 2013

Extensions Of S-Spaces, Bernd Losert

Electronic Theses and Dissertations

Given a convergence space X, a continuous action of a convergence semigroup S on X and a compactification Y of X, under what conditions on X and the action on X is it possible to extend the action to a continuous action on Y . Similarly, given a Cauchy space X, a Cauchy continuous action of a Cauchy semigroup S on X and a completion Y of X, under what conditions on X and the action on X is it possible to extend the action to a Cauchy continuous action on Y . We answer the first question for some …


Well-Covered Graphs, Unique Colorability, And Covering Range, Wanda Renea Payne Jan 2013

Well-Covered Graphs, Unique Colorability, And Covering Range, Wanda Renea Payne

Electronic Theses and Dissertations

A graph is called well-covered if all of its maximal independent sets have the same cardinality. We give a characterization of well-covered k-trees. A graph is said to be uniquely χ-colorable if, modulo permutations of colors, it has exactly one proper χ-coloring. The k-trees with at least k+1 vertices are minimal uniquely (k +1)-colorable, i.e., they have the minimal number of edges necessary for uniquely (k+1)-colorable graphs. We introduce the k-frames, a new class of minimal uniquely (k+1)-colorable graphs that generalizes the k-trees.

The covering range of a graph is the difference between the cardinality of a largest maximal independent …


Hjb Equation And Statistical Arbitrage Applied To High Frequency Trading, Yonggi Park Jan 2013

Hjb Equation And Statistical Arbitrage Applied To High Frequency Trading, Yonggi Park

Electronic Theses and Dissertations

In this thesis we investigate some properties of market making and statistical arbitrage applied to High Frequency Trading (HFT). Using the Hamilton-Jacobi-Bellman(HJB) model developed by Guilbaud, Fabien and Pham, Huyen in 2012, we studied how market making works to obtain optimal strategy during limit order and market order. Also we develop the best investment strategy through Moving Average, Exponential Moving Average, Relative Strength Index, Sharpe Ratio.


Accelerated Life Model With Various Types Of Censored Data, Kathryn Pridemore Jan 2013

Accelerated Life Model With Various Types Of Censored Data, Kathryn Pridemore

Electronic Theses and Dissertations

The Accelerated Life Model is one of the most commonly used tools in the analysis of survival data which are frequently encountered in medical research and reliability studies. In these types of studies we often deal with complicated data sets for which we cannot observe the complete data set in practical situations due to censoring. Such difficulties are particularly apparent by the fact that there is little work in statistical literature on the Accelerated Life Model for complicated types of censored data sets, such as doubly censored data, interval censored data, and partly interval censored data. In this work, we …


On Binary And Regular Matroids Without Small Minors, Kayla Davis Harville Jan 2013

On Binary And Regular Matroids Without Small Minors, Kayla Davis Harville

Electronic Theses and Dissertations

The results of this dissertation consist of excluded-minor results for Binary Matroids and excluded-minor results for Regular Matroids. Structural theorems on the relationship between minors and k-sums of matroids are developed here in order to provide some of these characterizations. Chapter 2 of the dissertation contains excluded-minor results for Binary Matroids. The first main result of this dissertation is a characterization of the internally 4-connected binary matroids with no minor that is isomorphic to the cycle matroid of the prism+e graph. This characterization generalizes results of Mayhew and Royle [18] for binary matroids and results of Dirac [8] and Lovász …


Pressure Poisson Method For The Incompressible Navier-Stokes Equations Using Galerkin Finite Elements, John Cornthwaite Jan 2013

Pressure Poisson Method For The Incompressible Navier-Stokes Equations Using Galerkin Finite Elements, John Cornthwaite

Electronic Theses and Dissertations

In this thesis we examine the Navier-Stokes equations (NSE) with the continuity equation replaced by a pressure Poisson equation (PPE). Appropriate boundary conditions are developed for the PPE, which allow for a fully decoupled numerical scheme to recover the pressure. The variational form of the NSE with PPE is derived and used in the Galerkin Finite Element discretization. The Galerkin finite element method is then used to solve the NSE with PPE. Moderate accuracy is shown.