Mathematics Commons^™

Applications And Adaptations Of A Globally Convergent Numerical Method In Inverse Problems, Aubrey Rhoden

Mathematics Dissertations - Archive

In our terminology "globally convergent numerical method" means a numerical method whose convergence to a good approximation of the correct solution is independent of the initial approximation in inverse problems. A numerical imaging algorithm has been proposed to solve a coecient inverse problem for an elliptic equation and then the algorithm is validated with the data generated by computer simulation. Previouswork in this eld was focused on the steady-state optical problem with multiple source positions moving along a straight line as well as the frequency domain problem with sweeping frequency. This work includes the steady-state thermal tomography problem with multiple …

Optimal Stopping For Markov Modulated Ito-Diffusion With Applications To Finance, Thomas William Seaquist

Mathematics Dissertations - Archive

Despite the outstanding success of the Black-Scholes model, it relies on the assumption that drift and volatility of the underlying equity remain constant throughout time. This inaccuracy has motivated a number of interesting and innovative refinements, one of the most natural being Markov modulation. In this dissertation we analyze a variety of financially motivated optimal stopping problems under Markov modulated Ito-Diffusions. In Chapter 3, we generalize and refine a technique developed in [13] pricing an infinite time horizon American put option and we present a rigorous proof of optimality. In Chapter 3 we use this generalized technique to discover an …

Mathematical Models Of Nutrient Recycling And Toxin Production In A Gradostat, Xiaoyang Dong

Mathematics Dissertations - Archive

We discuss several gradostat models in which a microbial population excretes a biochemical that can get recycled back into the system as a nutrient source. Each mathematical model consists of six ordinary differential equations and represents the dynamics of harmful algal blooms in lakes with fringing coves. We examine three different situations of biochemical production which is based on the algal growth rate, mortality, and nutrient concentration, respectively. Local and global stability analysis of the equilibria predicts that algal abundance and biochemical concentration can be both washed out or persistent under different environmental conditions. All theoretical results are supported by …

High Order Numerical Schemes For Pdes And Applications To Cfd, Huankun Fu

Mathematics Dissertations - Archive

In the past two decades, many efforts have been made in developing high-order schemes with high resolution, such as compact scheme, essentially non-oscillatory scheme (ENO), weighted essentially non-oscillatory scheme (WENO).The present dissertation comprises the analysis and numerical testing of two high order methods. The first one refers to the modification of pseudo spectral method which can be used to partial differential equations(PDEs) with non-periodic boundary conditions. The second one is in high order finite difference class and is the mixing of weighted non-oscillatory scheme and compact scheme (MWCS) with using global weights instead of local ones. Numerical tests are performed …

Adiabatic Flame Temperature For Combustion Of Methane Ii, Rebeca Pupo

Undergraduate Journal of Mathematical Modeling: One + Two

We calculate the adiabatic flame temperature of a mixture of methane and oxygen in the presence of a diluent gas then determine the mole fractions of methane without respect to nitrogen and solve for the moles of oxygen present. Knowing the moles of methane and oxygen, allows us to calculate the moles of nitrogen present at four constant mole fractions of nitrogen, and the adiabatic flame temperature is determined from the energy released by the reaction. Lastly, we produce several graphs to compare the adiabatic flame temperatures at different mole fractions of nitrogen.

Diffusion Of Vitamin B12 Across A Mesoporous Metal Organic Framework, Veronica Valencia

Undergraduate Journal of Mathematical Modeling: One + Two

We measure the rate of uptake and the rate of release of a Vitamin B12 solution (dissolved in water) at 2 different temperatures (room temperature and 37°C) by the mesoporous metal organic framework TbMOF-100 at 1-hour intervals using a spectrophotometer. Using the Beer-Lambert law, we calculate the concentration of the stock solution based on the absorbance values obtained with the spectrophotometer. These values allow for the quantification of the initial rate of uptake and the rate of uptake at a random incubation time of the Vitamin B12 by the TbMOF-100. We also calculate the value of the coefficient of diffusion …

Finding The Area Of A Major League Baseball Field, Jacob Courchaine

Undergraduate Journal of Mathematical Modeling: One + Two

Using a Major League Baseball (MLB) baseball field template for guidelines, we estimate the cost of building the largest possible field accepted under MLB standards. This includes finding the areas of both the clay and grassy regions and determining how many bags of clay and fertilizer are required to cover the field.

Elementary College Geometry, Henry Africk

Open Educational Resources

This text is intended for a brief introductory course in plane geometry. It covers the topics from elementary geometry that are most likely to be required for more advanced mathematics courses. The only prerequisite is a semester of algebra.

The emphasis is on applying basic geometric principles to the numerical solution of problems. For this purpose the number of theorems and definitions is kept small. Proofs are short and intuitive, mostly in the style of those found in a typical trigonometry or precalculus text. There is little attempt to teach theorem-proving or formal methods of reasoning. However the topics are …

Localized Bases For Kernel Spaces On The Unit Sphere, E. Fuselier, T. Hangelbroek, F. J. Narcowich, J. D. Ward, G. B. Wright

Mathematics Faculty Publications and Presentations

Approximation/interpolation from spaces of positive definite or conditionally positive definite kernels is an increasingly popular tool for the analysis and synthesis of scattered data and is central to many meshless methods. For a set of N scattered sites, the standard basis for such a space utilizes N globally supported kernels; computing with it is prohibitively expensive for large N. Easily computable, well-localized bases with “small-footprint” basis elements—i.e., elements using only a small number of kernels—have been unavailable. Working on S², with focus on the restricted surface spline kernels (e.g., the thin-plate splines restricted to the sphere), we …

Prospective Teachers’ Learning In Geometry: Changes In Discourse And Thinking, Sasha Wang

Mathematics Faculty Publications and Presentations

This study investigates changes in prospective teachers’ levels of geometric thinking and the development of their geometric discourses in the classification of quadrilaterals. To examine prospective teachers’ thinking about geometry, this study connects Sfard’s discursive framework to another, namely the van Hiele theory. Findings of the study reveal discursive similarities and differences in participants’ geometric discourses within the same van Hiele level, as well as changes in geometric discourse as a result of changes in levels of geometric thinking. The study also investigates the usefulness of a discursive framework in providing rich descriptions of prospective teachers’ thinking processes.

Understanding Prospective Teachers’ Levels Of Geometric Thoughts: Insights From A Discursive Analysis, Sasha Wang

Mathematics Faculty Publications and Presentations

The study investigates the characteristics of prospective teachers’ geometric discourses at the van Hiele model of thinking (1959/1985), using Sfard’s (2008) discursive framework. In this report, I align two prospective teachers’ pre- and post- van Hiele geometry test (Usiskin, 1982) results with the analyses of their geometric discourses from clinical interviews, to illustrate changes in geometric discourse when a student’s test results showed no change in van Hiele levels, and changes in geometric discourse when a student developed her thinking to the next van Hiele level. Revisiting the van Hiele model of thinking, complemented with a discursive lens, helped to …

New Microarray Image Segmentation Using Segmentation Based Contours Method, Yuan Cheng

Doctoral Dissertations

The goal of the research developed in this dissertation is to develop a more accurate segmentation method for Affymetrix microarray images. The Affymetrix microarray biotechnologies have become increasingly important in the biomedical research field. Affymetrix microarray images are widely used in disease diagnostics and disease control. They are capable of monitoring the expression levels of thousands of genes simultaneously. Hence, scientists can get a deep understanding on genomic regulation, interaction and expression by using such tools.

We also introduce a novel Affymetrix microarray image simulation model and how the Affymetrix microarray image is simulated by using this model. This simulation …

Sasakian Finsler Manifolds, Ayşe Funda Yaliniz, Nesri̇n Çalişkan

Turkish Journal of Mathematics

In this study, almost contact Finsler structures on vector bundle are defined and the condition of normality in terms of the Nijenhuis torsion N_{\phi} of almost contact Finsler structure is obtained. It is shown that for a K-contact structure on Finsler manifold \nabla_X \xi =-\frac{1}{2} \phi X and the flag curvature for plane sections containing \xi are equal to \frac{1}{4}. By using the Sasakian Finsler structure, the curvatures of a Finsler connection \nabla on V are obtained. We prove that a locally symmetric Finsler manifold with K-contact Finsler structure has a constant curvature \frac{1}{4}. Also, the Ricci curvature on Finsler …

Products Of Conjugacy Classes And Products Of Irreducible Characters In Finite Groups, Mohammad Reza Darafsheh, Sajjad Mahmood Robati

Turkish Journal of Mathematics

Let G be a finite group. If A and B are two conjugacy classes in G, then AB is a union of conjugacy classes in G and \eta(AB) denotes the number of distinct conjugacy classes of G contained in AB. If \chi and \psi are two complex irreducible characters of G, then \chi\psi is a character of G and again we let \eta(\chi\psi) be the number of irreducible characters of G appearing as constituents of \chi\psi. In this paper our aim is to study the product of conjugacy classes in a finite group and obtain an upper bound for \eta …

Software Development For A 3d Gravity Inversion And Application To Study Of The Border Ranges Fault System, South-Central Alaska, Rolando Cardenas

Open Access Theses & Dissertations

The Border Ranges Fault System (BRFS) bounds the Cook Inlet and Susitna Basins, and is an important petroleum province within south-central Alaska. A primary goal of our research is to test several plausible models of structure along the BRFS using a novel three-dimensional inversion technique utilizing gravity data, constrained with other geophysical, borehole and surface geological information. This research involves the development of 3D inversion modeling software using C++ Builder from Embarcadero's XE2 Suite. The novel inversion approach directly models known geology with a priori uncertainties assigned to the geologic model to allow researchers to compare alternative interpretations. This technique …

Riemannian Submersions And Lagrangian Isometric Immerson 1, Yun Myung Oh

Faculty Publications

In [1], it has shown that if a Riemannian manifold admits a non- trivial Riemannian submersion with total geodesic fibers, then it cannot be isometrically immersed in any Riemannian manifold of non-positive sectional curvature as a minimal submanifold. In this paper, we consider a nontrivial Riemannian submersion and investigate some properties on Lagrangian iso- metric immersions using the submersion invariant.

Nominal Regular Expressions For Languages Over Infinite Alphabets, Alexander Kurz, Tomoyuki Suzuki, Emilio Tuosto

Engineering Faculty Articles and Research

We propose regular expressions to abstractly model and study properties of resource-aware computations. Inspired by nominal techniques – as those popular in process calculi – we extend classical regular expressions with names (to model computational resources) and suitable operators (for allocation, deallocation, scoping of, and freshness conditions on resources). We discuss classes of such nominal regular expressions, show how such expressions have natural interpretations in terms of languages over infinite alphabets, and give Kleene theorems to characterise their formal languages in terms of nominal automata.

Relation Lifting, With An Application To The Many-Valued Cover Modality, Marta Bílková, Alexander Kurz, Daniela Petrişan, Jirí Velebil

Engineering Faculty Articles and Research

We introduce basic notions and results about relation liftings on categories enriched in a commutative quantale. We derive two necessary and sufficient conditions for a 2-functor T to admit a functorial relation lifting: one is the existence of a distributive law of T over the “powerset monad” on categories, one is the preservation by T of “exactness” of certain squares. Both characterisations are generalisations of the “classical” results known for set functors: the first characterisation generalises the existence of a distributive law over the genuine powerset monad, the second generalises preservation of weak pullbacks.

The results presented in this paper …

Epistemic Updates On Algebras, Alexander Kurz, Alessandra Palmigiano

Engineering Faculty Articles and Research

We develop the mathematical theory of epistemic updates with the tools of duality theory. We focus on the Logic of Epistemic Actions and Knowledge (EAK), introduced by Baltag-Moss-Solecki, without the common knowledge operator. We dually characterize the product update construction of EAK as a certain construction transforming the complex algebras associated with the given model into the complex algebra associated with the updated model. This dual characterization naturally generalizes to much wider classes of algebras, which include, but are not limited to, arbitrary BAOs and arbitrary modal expansions of Heyting algebras (HAOs). As an application of this dual characterization, we …

Modeling Dengue Virus Infection Patients For Each Severity Of Dengue Disease In Thailand, Montip Tiensuwan, Timothy O'Brien

Mathematics and Statistics: Faculty Publications and Other Works

Dengue is an infectious mosquito-borne viral disease. Dengue or dengue-like epidemics ranks highly among new and newly emerging infectious diseases in public health significance and may affect persons of all ages in dengue endemic area. Dengue virus infections may lead to dengue fever (DF), dengue haemorrhagic fever (DHF) and may lead to hypovolaemic shock (dengue shock syndrome, DSS) then we separate dengue data by severity of dengue disease, i.e., DF, DHF and DSS. The objective of this study is to find factors which affect the dengue virus infection patients for each severity of dengue disease in Thailand by using multiple …

The Eichler-Selberg Trace Formula For Level-One Hecke Operators, Alex Barron

Honors Theses

This paper explains the steps involved in the proof of the Eichler-Selberg Trace Formula for Hecke operators of level one. It is based on an appendix in Serge Lang's Introduction to Modular Forms written by Don Zagier, though I also draw heavily from sections of Toshitsune Miyake's Modular Forms and Xueli Wang's and Dingyi Pei's Modular Forms with Integral and Half-Integral Weights.

Section 2 summarizes the necessary background in the theory of modular forms. The material covered here is standard, so I've left out most of the details and proofs. Most of the section is based on Chapter VII of …

Sparse Group Sufficient Dimension Reduction And Covariance Cumulative Slicing Estimation, Bilin Zeng

Doctoral Dissertations

"This dissertation contains two main parts: In Part One, for regression problems with grouped covariates, we adopt the idea of sparse group lasso (Friedman et al., 2010) to the framework of the sufficient dimension reduction. We propose a method called the sparse group sufficient dimension reduction (sgSDR) to conduct group and within group variable selections simultaneously without assuming a specific model structure on the regression function. Simulation studies show that our method is comparable to the sparse group lasso under the regular linear model setting, and outperforms sparse group lasso with higher true positive rates and substantially lower false positive …

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 …

Theory And Applications Of Correspondences, Heather Olson

The Journal of Undergraduate Research

Throughout this paper, we will examine correspondences, also known as set-valued functions. A definition of correspondences and their graphs are given. Properties of correspondences including continuity, optimization, and existence of fixed points are considered. Examples are considered demonstrating these properties. Applications in the field of Economics are introduced. Specifically the optimization of consumer utility is examined through examples.

Laughing At The Looking Glass: Does Humor Style Serve As An Interpersonal Signal?, Virgil Zeigler-Hill, Avi Besser, Stephanie E. Jett

Faculty Publications

Objective: The provision of information appears to be an important feature of humor. The present studies examined whether humor serves as an interpersonal signal such that an individual's style of humor is associated with how the individual is perceived by others. Method: We examined this issue across two studies. In Study 1, undergraduate participants (257 targets) were rated more positively by their friends and family members (1194 perceivers) when they possessed more benign humor styles. In Study 2, 1190 community participants rated the romantic desirability of targets ostensibly possessing different humor styles. Results: Across both studies, our results were consistent …

Constructions And Enumeration Methods For Cubic Graphs And Trees, Erica R. Gilliland

Undergraduate Honors Thesis Collection

The goal of this thesis is to study two related problems that, in the broadest terms, lie in a branch of mathematics called graph theory. The first problem examines some new techniques for constructing a Hamilton graph of least possible order and having a preassigned girth, and the second concerns the enumeration of a certain type of graphs called trees.

Spectral Multiplicity Of Selfadjoint Schrodinger Operators On Star-Graphs With Standard Interface Conditions, Sergey Simonov, Harald Woracek

Articles

We analyze the singular spectrum of selfadjoint operators which arise from pasting a finite number of boundary relations with a standard interface condition. A model example for this situation is a Schroedinger operator on a star-shaped graph with continuity and Kirchhoff conditions at the interior vertex. We compute the multiplicity of the singular spectrum in terms of the spectral measures of the Weyl functions associated with the single (independently considered) boundary relations. This result is a generalization and refinement of Theorem of I.S. Kac.

Extreme Wave Events In Ireland: 14 680 Bp–2012, Laura Cooke, John M. Dudley, Frédéric Dias

Articles

The island of Ireland is battered by waves from all sides, most ferociously on the west coast as the first port of call for waves travelling across the Atlantic Ocean. However, when discussing ocean events relevant to the nation of Ire- land, one must actually consider its significantly larger designated continental shelf, which is one of the largest seabed territories in Europe. With this expanded definition, it is not surprising that Ireland has been subject to many oceanic events which could be designated as “extreme”; in this paper we present what we believe to be the first catalogue of such …

Student Success In Subsequent Mathematics Courses After Taking Ma 004, Andrea Winchester

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

A Comparison Of Smale Spaces And Laminations Via Inverse Limits, Rebecca Elizabeth Targove

All Graduate Theses, Dissertations, and Other Capstone Projects

Inverse limits began as a purely topological concept, but have since been applied to areas such as dynamical systems and manifold theory. R.F. Williams related inverse limits to dynamical systems by presenting a construction and realization result relating expanding attractors to inverse limits of branched manifolds. Wieler then adapted these results for Smale Spaces with totally disconnected local stable sets. Rojo used tiling space results to relate inverse limits of branched manifolds to codimension zero laminations. This paper examines the results of Wieler and Rojo and shows that they are analogous.