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Articles 31 - 60 of 185

Full-Text Articles in Physical Sciences and Mathematics

Loop Numbers Of Knots And Links, Van Anh Pham Apr 2017

Loop Numbers Of Knots And Links, Van Anh Pham

Masters Theses & Specialist Projects

This thesis introduces a new quantity called loop number, and shows the conditions in which loop numbers become knot invariants. For a given knot diagram D, one can traverse the knot diagram and count the number of loops created by the traversal. The number of loops recorded depends on the starting point in the diagram D and on the traversal direction. Looking at the minimum or maximum number of loops over all starting points and directions, one can define two positive integers as loop numbers of the diagram D. In this thesis, the conditions under which these loop numbers become …


Density-Dependent Leslie Matrix Modeling For Logistic Populations With Steady-State Distribution Control, Bruce Kessler, Andrew Davis Dec 2016

Density-Dependent Leslie Matrix Modeling For Logistic Populations With Steady-State Distribution Control, Bruce Kessler, Andrew Davis

Mathematics Faculty Publications

The Leslie matrix model allows for the discrete modeling of population age-groups whose total population grows exponentially. Many attempts have been made to adapt this model to a logistic model with a carrying capacity (see [1], [2], [4], [5], and [6]), with mixed results. In this paper we provide a new model for logistic populations that tracks age-group populations with repeated multiplication of a density-dependent matrix constructed from an original Leslie matrix, the chosen carrying capacity of the model, and the desired steady-state age-group distribution. The total populations from the model converge to a discrete logistic model with the same …


Incorporating Exponential Functions Into An Optimal Control Model For A Chronic Wound, Peter Agaba Aug 2016

Incorporating Exponential Functions Into An Optimal Control Model For A Chronic Wound, Peter Agaba

Mahurin Honors College Capstone Experience/Thesis Projects

A chronic wound is a wound that does not heal in an orderly manner and on time. In this project, we simulate different ways of minimizing the time of therapy using exponential functions. The analysis in this research project focuses on treating chronic wounds using both mathematical and biological models. These models primarily focus on the amount of oxygen supplied to the wound using both hyperbaric and topical oxygen therapies. This amount should be optimal since too much oxygen is toxic to the body, and can potentially lead to death. The goal is to minimize the time spent in therapies …


A Classification Of The Intersections Between Regions And Their Topical Transitions, Kathleen Bell Aug 2016

A Classification Of The Intersections Between Regions And Their Topical Transitions, Kathleen Bell

Mahurin Honors College Capstone Experience/Thesis Projects

As two topological regions are morphed and translated, how does their intersection change? Previous research has been done on static configurations with planar spatial regions. I expand upon this research to include dynamically changing regions and intersections. I examine what forms of intersection are possible, and what transitions are directly possible, while considering such variables as the connectedness of the regions.


Ogden College Of Science & Engineering Newsletter (Summer 2016), Cheryl Stevens, Dean Jul 2016

Ogden College Of Science & Engineering Newsletter (Summer 2016), Cheryl Stevens, Dean

Ogden College of Science & Engineering Publications

No abstract provided.


Nullification Of Torus Knots And Links, Zachary S. Bettersworth Jul 2016

Nullification Of Torus Knots And Links, Zachary S. Bettersworth

Masters Theses & Specialist Projects

Knot nullification is an unknotting operation performed on knots and links that can be used to model DNA recombination moves of circular DNA molecules in the laboratory. Thus nullification is a biologically relevant operation that should be studied.

Nullification moves can be naturally grouped into two classes: coherent nullification, which preserves the orientation of the knot, and incoherent nullification, which changes the orientation of the knot. We define the coherent (incoherent) nullification number of a knot or link as the minimal number of coherent (incoherent) nullification moves needed to unknot any knot or link. This thesis concentrates on the study …


Two Generalizations Of The Filippov Operation, Menevse Eryuzlu Apr 2016

Two Generalizations Of The Filippov Operation, Menevse Eryuzlu

Masters Theses & Specialist Projects

The purpose of this thesis is to generalize Filippov's operation, and to get more useful results. It includes two main parts: The C-Filippov operation for the finite and countable cases and the Filippov operation with different measures. In the first chapter, we give brief information about the importance of Filippov's operation, our goal and the ideas behind our generalizations. In the second chapter, we give some sufficient background notes. In the third chapter, we introduce the Filippov operation, explain how to calculate the Filippov of a function and give some sufficient properties of it. In the fourth chapter, we introduce …


Ogden College Of Science & Engineering Newsletter (Spring 2016), Cheryl Stevens, Dean, Ogden College Of Science & Engineering Mar 2016

Ogden College Of Science & Engineering Newsletter (Spring 2016), Cheryl Stevens, Dean, Ogden College Of Science & Engineering

Ogden College of Science & Engineering Publications

No abstract provided.


Ogden College Of Science & Engineering Newsletter (Fall 2015), Cheryl Stevens, Dean Oct 2015

Ogden College Of Science & Engineering Newsletter (Fall 2015), Cheryl Stevens, Dean

Ogden College of Science & Engineering Publications

No abstract provided.


Expectation Numbers Of Cyclic Groups, Miriam Mahannah El-Farrah Jul 2015

Expectation Numbers Of Cyclic Groups, Miriam Mahannah El-Farrah

Masters Theses & Specialist Projects

When choosing k random elements from a group the kth expectation number is the expected size of the subgroup generated by those specific elements. The main purpose of this thesis is to study the asymptotic properties for the first and second expectation numbers of large cyclic groups. The first chapter introduces the kth expectation number. This formula allows us to determine the expected size of any group. Explicit examples and computations of the first and second expectation number are given in the second chapter. Here we show example of both cyclic and dihedral groups. In chapter three we discuss arithmetic …


Ogden College Of Science & Engineering Newsletter (Summer 2015), Cheryl Stevens, Dean May 2015

Ogden College Of Science & Engineering Newsletter (Summer 2015), Cheryl Stevens, Dean

Ogden College of Science & Engineering Publications

No abstract provided.


Counting Convex Sets On Products Of Totally Ordered Sets, Brandy Amanda Barnette May 2015

Counting Convex Sets On Products Of Totally Ordered Sets, Brandy Amanda Barnette

Masters Theses & Specialist Projects

The main purpose of this thesis is to find the number of convex sets on a product of two totally ordered spaces. We will give formulas to find this number for specific cases and describe a process to obtain this number for all such spaces. In the first chapter we briefly discuss the motivation behind the work presented in this thesis. Also, the definitions and notation used throughout the paper are introduced here The second chapter starts with examining the product spaces of the form {1; 2; : : : ;n} × {1; 2}. That is, we begin by analyzing …


Analysis Of Discrete Fractional Operators And Discrete Fractional Rheological Models, Meltem Uyanik May 2015

Analysis Of Discrete Fractional Operators And Discrete Fractional Rheological Models, Meltem Uyanik

Masters Theses & Specialist Projects

This thesis is comprised of two main parts: Monotonicity results on discrete fractional operators and discrete fractional rheological constitutive equations. In the first part of the thesis, we introduce and prove new monotonicity concepts in discrete fractional calculus. In the remainder, we carry previous results about fractional rheological models to the discrete fractional case. The discrete method is expected to provide a better understanding of the concept than the continuous case as this has been the case in the past. In the first chapter, we give brief information about the main results. In the second chapter, we present some fundamental …


Boundary Problems For One And Two Dimensional Random Walks, Miky Wright May 2015

Boundary Problems For One And Two Dimensional Random Walks, Miky Wright

Masters Theses & Specialist Projects

This thesis provides a study of various boundary problems for one and two dimensional random walks. We first consider a one-dimensional random walk that starts at integer-valued height k > 0, with a lower boundary being the x-axis, and on each step moving downward with probability q being greater than or equal to the probability of going upward p. We derive the variance and the standard deviation of the number of steps T needed for the height to reach 0 from k, by first deriving the moment generating function of T. We then study two types of two-dimensional random walks with …


Ogden College Of Science & Engineering Newsletter (Spring 2015), Cheryl Stevens, Dean Mar 2015

Ogden College Of Science & Engineering Newsletter (Spring 2015), Cheryl Stevens, Dean

Ogden College of Science & Engineering Publications

No abstract provided.


Ogden College Of Science & Engineering Newsletter (Winter 2015), Cheryl Stevens, Dean Jan 2015

Ogden College Of Science & Engineering Newsletter (Winter 2015), Cheryl Stevens, Dean

Ogden College of Science & Engineering Publications

No abstract provided.


Ogden College Of Science & Engineering Newsletter (Winter 2014), Cheryl Stevens, Dean Dec 2014

Ogden College Of Science & Engineering Newsletter (Winter 2014), Cheryl Stevens, Dean

Ogden College of Science & Engineering Publications

No abstract provided.


Ogden College Of Science & Engineering Newsletter (Fall 2014), Cheryl Stevens, Dean Oct 2014

Ogden College Of Science & Engineering Newsletter (Fall 2014), Cheryl Stevens, Dean

Ogden College of Science & Engineering Publications

No abstract provided.


The Effects Of Standards-Based Grading On Student Performance In Algebra 2, Rachel Beth Rosales Dec 2013

The Effects Of Standards-Based Grading On Student Performance In Algebra 2, Rachel Beth Rosales

Dissertations

The use of standards-based grading in American public schools is increasing, offering students, parents, and teachers a new way of measuring and communicating about student achievement and performance. Parents indicate an appreciation for this method of grading, and students at the elementary grades (K-6) have improved standardized test scores in reading and math as a result of its implementation. This study seeks to determine whether standards-based grading has the same effect on students at the high school level (grades 9-12) by comparing end-of-course test scores and posttest scores of Algebra 2 students enrolled in a standards-based graded classroom with to …


Ogden College Of Science & Engineering Newsletter (Winter 2013), Cheryl Stevens, Dean Dec 2013

Ogden College Of Science & Engineering Newsletter (Winter 2013), Cheryl Stevens, Dean

Ogden College of Science & Engineering Publications

No abstract provided.


Leslie Matrices For Logistic Population Modeling, Bruce Kessler Nov 2013

Leslie Matrices For Logistic Population Modeling, Bruce Kessler

Mathematics Faculty Publications

Leslie matrices are taught as a method of modeling populations in a discrete-time fashion with more detail in the tracking of age groups within the population. Leslie matrices have limited use in the actual modeling of populations, since when the age groups are summed, it is basically equivalent to discrete-time modeling assuming exponential population growth. The logistic model of population growth is more realistic, since it takes into account a carrying capacity for the environment of the population. This talk will describe an adjustment to the Leslie matrix approach for population modeling that is both takes into account the carrying …


Leslie Matrices For Logistic Population Modeling, Bruce Kessler Nov 2013

Leslie Matrices For Logistic Population Modeling, Bruce Kessler

Bruce Kessler

Leslie matrices are taught as a method of modeling populations in a discrete-time fashion with more detail in the tracking of age groups within the population. Leslie matrices have limited use in the actual modeling of populations, since when the age groups are summed, it is basically equivalent to discrete-time modeling assuming exponential population growth. The logistic model of population growth is more realistic, since it takes into account a carrying capacity for the environment of the population. This talk will describe an adjustment to the Leslie matrix approach for population modeling that is both takes into account the carrying …


Four-Sided Boundary Problem For Two-Dimensional Random Walks, Miky Wright Aug 2013

Four-Sided Boundary Problem For Two-Dimensional Random Walks, Miky Wright

Mahurin Honors College Capstone Experience/Thesis Projects

Within the four-sided boundaries of x = 0, y = 0, x = m and, y = n, a two-dimensional random walk begins at integer-valued coordinates (h,k) and moves one unit on each step either up, down, left, or right with non-zero probabilities that sum to 1. The process stops when hitting a boundary. Let P(U), P(D), P(L) and P(R) be the probabilities of hitting the upper, the lower, the left, and the right boundary first, respectively, when starting from a specific initial point within the boundaries. We use a Markov-Chain method to compute these probabilities. Let …


Long-Wave Model For Strongly Anisotropic Growth Of A Crystal Step, Mikhail Khenner Aug 2013

Long-Wave Model For Strongly Anisotropic Growth Of A Crystal Step, Mikhail Khenner

Mathematics Faculty Publications

A continuum model for the dynamics of a single step with the strongly anisotropic line energy is formulated and analyzed. The step grows by attachment of adatoms from the lower terrace, onto which atoms adsorb from a vapor phase or from a molecular beam, and the desorption is nonnegligible (the “one-sided” model). Via a multiscale expansion, we derived a long-wave, strongly nonlinear, and strongly anisotropic evolution PDE for the step profile. Written in terms of the step slope, the PDE can be represented in a form similar to a convective Cahn-Hilliard equation. We performed the linear stability analysis and computed …


Long-Wave Model For Strongly Anisotropic Growth Of A Crystal Step, Mikhail Khenner Aug 2013

Long-Wave Model For Strongly Anisotropic Growth Of A Crystal Step, Mikhail Khenner

Mikhail Khenner

A continuum model for the dynamics of a single step with the strongly anisotropic line energy is formulated and analyzed. The step grows by attachment of adatoms from the lower terrace, onto which atoms adsorb from a vapor phase or from a molecular beam, and the desorption is nonnegligible (the “one-sided” model). Via a multiscale expansion, we derived a long-wave, strongly nonlinear, and strongly anisotropic evolution PDE for the step profile. Written in terms of the step slope, the PDE can be represented in a form similar to a convective Cahn-Hilliard equation. We performed the linear stability analysis and computed …


Using Partial Differential Equations To Model And Analyze The Treatment Of A Chronic Wound With Oxygen Therapy Techniques, Brandon C. Russell May 2013

Using Partial Differential Equations To Model And Analyze The Treatment Of A Chronic Wound With Oxygen Therapy Techniques, Brandon C. Russell

Mahurin Honors College Capstone Experience/Thesis Projects

Chronic wounds plague approximately 1.3-3 million Americans. The treatment of these wounds requires knowledge of the complex healing process of typical wounds. With a system of partial differential equations, this project attempts to model the intricate biological process and to describe oxygen levels, neutrophil and bacteria concentrations, and other biological parameters with respect to time and space. Analytical solutions for the model will be derived for various frames of time in the wound-healing process. The system of equations will be numerically solved using Matlab. Numerical simulations are performed to determine optimal treatment strategies for a chronic wound.


The Torsion Angle Of Random Walks, Mu He May 2013

The Torsion Angle Of Random Walks, Mu He

Masters Theses & Specialist Projects

In this thesis, we study the expected mean of the torsion angle of an n-step
equilateral random walk in 3D. We consider the random walk is generated within a confining sphere or without a confining sphere: given three consecutive vectors e1 , e2 , and e3 of the random walk then the vectors e1 and e2 define a plane and the vectors e2 and e3 define a second plane. The angle between the two planes is called the torsion angle of the three vectors. Algorithms are …


Minimizing Travel Time Through Multiple Media With Various Borders, Tonja Miick May 2013

Minimizing Travel Time Through Multiple Media With Various Borders, Tonja Miick

Masters Theses & Specialist Projects

This thesis consists of two main chapters along with an introduction and
conclusion. In the introduction, we address the inspiration for the thesis, which
originates in a common calculus problem wherein travel time is minimized across two media separated by a single, straight boundary line. We then discuss the correlation of this problem with physics via Snells Law. The first core chapter takes this idea and develops it to include the concept of two media with a circular border. To make the problem easier to discuss, we talk about it in terms of running and swimming speeds. We first address …


Using Optimal Control Theory To Optimize The Use Of Oxygen Therapy In Chronic Wound Healing, Donna Lynn Daulton May 2013

Using Optimal Control Theory To Optimize The Use Of Oxygen Therapy In Chronic Wound Healing, Donna Lynn Daulton

Masters Theses & Specialist Projects

Approximately 2 to 3 million people in the United States suffer from chronic wounds, which are defined as wounds that do not heal in 30 days time; an estimated $25 billion per year is spent on their treatment in the United States. In our work, we focused on treating chronic wounds with bacterial infections using hyperbaric and topical oxygen therapies.

We used a mathematical model describing the interaction between bacteria, neutrophils and oxygen. Optimal control theory was then employed to study oxygen treatment strategies with the mathematical model. Existence of a solution was shown for both therapies. Uniqueness was also …


Floquet Theory On Banach Space, Fatimah Hassan Albasrawi May 2013

Floquet Theory On Banach Space, Fatimah Hassan Albasrawi

Masters Theses & Specialist Projects

In this thesis we study Floquet theory on a Banach space. We are concerned about the linear differential equation of the form: y'(t) = A(t)y(t), where t ∈ R, y(t) is a function with values in a Banach space X, and A(t) are linear, bounded operators on X. If the system is periodic, meaning A(t+ω) = A(t) for some period ω, then it is called a Floquet system. We will investigate the existence …