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Articles 421 - 450 of 1053
Full-Text Articles in Mathematics
Concurrent Neurological And Behavioral Assessment Of Number Line Estimation Performance In Children And Adults, Joseph Michael Baker
Concurrent Neurological And Behavioral Assessment Of Number Line Estimation Performance In Children And Adults, Joseph Michael Baker
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Understanding the brain’s response to common math-learning activities may help improve math education. For example, by imaging the brains of typically developing children and adults throughout a number line estimation task, it is possible to establish a baseline of what “typical” brains do in such situations. Thus, comparisons may be made to determine the degree to which brain functioning differs between typical and atypical math learners. Moreover, by identifying methods that may increase the brain’s response to real-world math activities, it may be possible to improve the math learning process for typical and atypical learners alike.
Brain imaging devices such …
Dot Product Graphs And Their Applications To Ecology, Sean Bailey
Dot Product Graphs And Their Applications To Ecology, Sean Bailey
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
We will introduce a new tool to visualize the comparison between different birds. This tool will allow users to use any number of measurable traits to see relationships between different birds, both individually and collectively.
Pricing European And American Options In The Heston Model With Accelerated Explicit Finite Differencing Methods, Conall O'Sullivan, Stephen O'Sullivan
Pricing European And American Options In The Heston Model With Accelerated Explicit Finite Differencing Methods, Conall O'Sullivan, Stephen O'Sullivan
Articles
No abstract provided.
Processing And Manipulation Of Data Collected From The Educational On-Line Game Refraction, Xiaotian Dai
Processing And Manipulation Of Data Collected From The Educational On-Line Game Refraction, Xiaotian Dai
All Graduate Plan B and other Reports, Spring 1920 to Spring 2023
A team of students, artists, and researchers at the Center for Game Science at the
University of Washington are trying to create video games that can discover optimal
pathways for learning. They have focused so far on early mathematics education,
including topics such as fractions and algebra, which are some of the main bottlenecks
preventing students from pursuing a career in science. As a result, the educational
on-line game \Refraction" was created, which is aimed at students who start learning
fraction computations. When the students are playing the game online, all the data
and information, such as mouse movements and …
Simulated Annealing Approach To Flow Shop Scheduling, Sadhana Yellanki
Simulated Annealing Approach To Flow Shop Scheduling, Sadhana Yellanki
UNLV Theses, Dissertations, Professional Papers, and Capstones
Flow Shop Scheduling refers to the process of allotting various jobs to the machines given, such that every job starts to process on a machine n only after it has finished processing on machine n-1, with each job having n operations to be performed one per machine. To find a schedule that leads to the optimal utilization of resources, expects the schedule to finish in a minimum span of time, and also satisfy the optimality criterion set for the related scheduling problem is NP-Hard, if n > 2. In this thesis, we have developed an algorithm adopting a heuristic called Simulated …
Discontinuous Galerkin Finite Element Methods For Maxwell's Equations In Dispersive And Metamaterials Media, Jiajia Waters
Discontinuous Galerkin Finite Element Methods For Maxwell's Equations In Dispersive And Metamaterials Media, Jiajia Waters
UNLV Theses, Dissertations, Professional Papers, and Capstones
Discontinuous Galerkin Finite Element Method (DG-FEM) has been further developed in this dissertation. We give a complete proof of stability and error estimate for the DG-FEM combined with Runge Kutta which is commonly used in different fields. The proved error estimate matches those numerical results seen in technical papers. Numerical simulations of metamaterials play a very important role in the design of invisibility cloak, and sub-wavelength imaging. We propose a leap-frog discontinuous Galerkin Finite Element Method to solve the time-dependent Maxwell's equations in metamaterials. The stability and error estimate are proved for this scheme. The proposed algorithm is implemented and …
Generalizations Of Pascal's Triangle: A Construction Based Approach, Michael Anton Kuhlmann
Generalizations Of Pascal's Triangle: A Construction Based Approach, Michael Anton Kuhlmann
UNLV Theses, Dissertations, Professional Papers, and Capstones
The study of this paper is based on current generalizations of Pascal's Triangle, both the expansion of the polynomial of one variable and the multivariate case. Our goal is to establish relationships between these generalizations, and to use the properties of the generalizations to create a new type of generalization for the multivariate case that can be represented in the third dimension.
In the first part of this paper we look at Pascal's original Triangle with properties and classical applications. We then look at contemporary extensions of the triangle to coefficient arrays for polynomials of two forms. The first of …
Symbolic Powers Of Ideals In K[PN], Michael Janssen
Symbolic Powers Of Ideals In K[PN], Michael Janssen
Department of Mathematics: Dissertations, Theses, and Student Research
Let I ⊆ k[PN] be a homogeneous ideal and k an algebraically closed field. Of particular interest over the last several years are ideal containments of symbolic powers of I in ordinary powers of I of the form I(m) ⊆ Ir, and which ratios m/r guarantee such containment. A result of Ein-Lazarsfeld-Smith and Hochster-Huneke states that, if I ⊆ k[PN], where k is an algebraically closed field, then the symbolic power I(Ne) is contained in the ordinary power Ie, and thus, whenever …
Traffic Modeling In Lagrangian Coordinates Using Smartphone Apps, Sergio Contreras
Traffic Modeling In Lagrangian Coordinates Using Smartphone Apps, Sergio Contreras
UNLV Theses, Dissertations, Professional Papers, and Capstones
Traditionally, one of the ways traffic flow has been studied is by using the kinematic wave model. This model is derived in the Eulerian framework by using conservation of the number of vehicles. Recently, the kinematic wave model has been transformed into Lagrangian coordinates. In this framework, the independent variables are unique
vehicles and time. The detailed change in framework, and the properties of the model in the changed framework are reviewed. Numerical results from different traffic cases are explained. Since vehicle trajectory data can be easily collected from smartphones,
a smartphone application is developed for this purpose. This data …
Uphill & Downhill Domination In Graphs And Related Graph Parameters., Jessie Deering
Uphill & Downhill Domination In Graphs And Related Graph Parameters., Jessie Deering
Undergraduate Honors Theses
Placing degree constraints on the vertices of a path allows the definitions of uphill and downhill paths. Specifically, we say that a path π = v1, v2,...vk+1 is a downhill path if for every i, 1 ≤ i ≤ k, deg(vi) ≥ deg(vi+1). Conversely, a path π = u1, u2,...uk+1 is an uphill path if for every i, 1 ≤ i ≤ k, deg(ui) ≤ deg(ui+1). We investigate graphical parameters related to downhill and …
A Variety Of Proofs Of The Steiner-Lehmus Theorem, Sherri R. Gardner
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.
Peg Solitaire On Trees With Diameter Four, Clayton A. Walvoort
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
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 …
Very Cost Effective Partitions In Graphs, Inna Vasylieva
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.
Several Problems Concerning Multivariate Functions And Associated Operators, Kelly Ann Bickel
Several Problems Concerning Multivariate Functions And Associated Operators, Kelly Ann Bickel
All Theses and Dissertations (ETDs)
This dissertation examines two distinct problems about multivariate functions and their associated operators. It first discusses the structure of Agler decompositions, which give useful ways to represent two-variable Schur functions on the bidisk using positive kernels. An elementary proof of the existence of Agler decompositions is provided, which uses special shift-invariant subspaces of the Hardy space. These shift-invariant subspaces are specific cases of Hilbert spaces that can be defined from Agler decompositions and their properties are analyzed. More specific results are obtained for certain classes of polynomials and rational inner functions.
Secondly, this dissertation examines differentiation of matrix-valued functions. Specifically, …
Image Processing Algorithms For Improving Planetary Exploration And Understanding, Ali Pouryazdanpanah
Image Processing Algorithms For Improving Planetary Exploration And Understanding, Ali Pouryazdanpanah
College of Engineering: Graduate Celebration Programs
- To design a fully automated tool-set that allows to detect and extract the sky region in planetary images.
- To develop the new method for rock segmentation in planetary stereo images.
- To develop the new method for shadow detection in planetary images
Mono-Sized Sphere Packing Algorithm Development Using Optimized Monte Carlo Technique, Karn Soontrapa, Yitung Chen
Mono-Sized Sphere Packing Algorithm Development Using Optimized Monte Carlo Technique, Karn Soontrapa, Yitung Chen
College of Engineering: Graduate Celebration Programs
In this research, fuel cell catalyst layer was developed using the optimized sphere packing algorithm. An optimization technique named adaptive random search technique (ARSET) was employed in this packing algorithm. The ARSET algorithm will generate the initial location of spheres and allow them to move in the random direction with the variable moving distance, randomly selected from the sampling range (a), based on the Lennard–Jones potential and Morse potential of the current and new configuration. The solid fraction values obtained from this developed algorithm are in the range of 0.610–0.624 while the actual processing time can significantly be reduced by …
Applied Analysis Of Ionic Polymer Metal-Composite Actuators, Siul Ruiz, Benjamin Mead, Woosoon Yim
Applied Analysis Of Ionic Polymer Metal-Composite Actuators, Siul Ruiz, Benjamin Mead, Woosoon Yim
College of Engineering: Graduate Celebration Programs
- IPMC is a type of smart material called an electroactive polymer
- Consists of an ionic polymer such as Nafion or Flemion and a conducive metal such as platinum or gold
- COMSOL multi-physics simulations accurately model the experimental displacement results
- Optimization performed using the multi-physics model to find the maximum deflection, force, and twisting
- Using the closed loop control system accurate IPMC tip location can be achieved
- This control system has been extended to function using a computer mouse as an input
Actual Vs. Perceived Value Of Players Of The National Basketball Association, Stephen Righini
Actual Vs. Perceived Value Of Players Of The National Basketball Association, Stephen Righini
Honors Projects in Mathematics
Over the past few decades the media has played an increasingly large role in shaping how player effectiveness in the National Basketball Association (NBA) is perceived. Several factors have caused fans, announcers, and even NBA team management to have unintentional bias toward certain players. This study aims to utilize various formulas created by NBA statisticians, called Player Raters, to identify how efficient each NBA player actually is in comparison to the rest of the league. Data from the past 12 seasons was compiled and six Player Raters were used to place values on every NBA player since the 2000-2001 season. …
Time Series Data Mining: A Retail Application Using Sas Enterprise Miner, Daniel Hebert
Time Series Data Mining: A Retail Application Using Sas Enterprise Miner, Daniel Hebert
Honors Projects in Mathematics
Modern technologies have allowed for the amassment of data at a rate never encountered before. Organizations are now able to routinely collect and process massive volumes of data. A plethora of regularly collected information can be ordered using an appropriate time interval. The data would thus be developed into a time series. With such data, analytical techniques can be employed to collect information pertaining to historical trends and seasonality. Time series data mining methodology allows users to identify commonalities between sets of time-ordered data. This technique is supported by a variety of algorithms, notably dynamic time warping (DTW). This mathematical …
Limit Theorems For Random Billiard Models, Timothy Chumley
Limit Theorems For Random Billiard Models, Timothy Chumley
All Theses and Dissertations (ETDs)
The central objects of study in this dissertation are random billiard systems. These are Markov chain systems with general state spaces derived from deterministic billiard systems by selecting one or more dynamical variables and replacing them with random variables with fixed probability distributions. In particular, we study two specific model systems; one which models gas diffusion through cylindrical channels whose walls have a microscopic structure, and another which models a minimalistic heat engine. The main results for the gas diffusion model, a series of probabilistic limit theorems, allow us to express transport characteristics such as mean exit times of the …
Sorting Permutations With Finite-Depth Stacks, Timothy Goodrich, Will Olson, Ruyue Yuan
Sorting Permutations With Finite-Depth Stacks, Timothy Goodrich, Will Olson, Ruyue Yuan
Symposium on Research and Creative Expression (SORCE)
Sorting organizes information for optimal usage, and our work examines the mathematics behind sorting with stacks. In 1968, Donald Knuth showed that a permutation is sortable in an infinite-depth stack if and only if it avoids the pattern 231; Knuth also enumerated these permutations. Twenty-five years later, Julian West extended these ideas to permutations sortable with 2 consecutive stacks. We continue this work by limiting the stack(s) to a finite depth. In particular, we completely characterize permutations sortable through a single finite-depth stack and derive a handy enumeration formula. We also apply our pattern characterization and enumeration techniques to permutations …
Simulation Modeling And Analysis Of Coal Shipping Operations, Raymond Finzel, Timothy Goodrich, Graeme Roberts
Simulation Modeling And Analysis Of Coal Shipping Operations, Raymond Finzel, Timothy Goodrich, Graeme Roberts
Symposium on Research and Creative Expression (SORCE)
Computer simulations are increasingly powerful and realistic models for complex real-world scenarios, and our project applies this technology to model a coal transportation case study. Given a baseline scenario of fourteen carriers transporting coal from three U.S. locations to four international locations, we optimize operations in terms of product flow, time required for shipments, and total operation costs. Implementing the case study's factors into modular code, we introduce several potential changes to current operations and develop specific scenarios. Further, in analyzing these scenarios we test for robustness and sensitivity, by changing values such as demand and bad weather occurrences, and …
Optimizing The Allocation Of Vaccines In The Presence Of Multiple Strains Of The Influenza Virus, Abby Kenyon, Ana Eveler, Tayler Grashel, Jessica Richardson
Optimizing The Allocation Of Vaccines In The Presence Of Multiple Strains Of The Influenza Virus, Abby Kenyon, Ana Eveler, Tayler Grashel, Jessica Richardson
Symposium on Research and Creative Expression (SORCE)
During the annual flu season, multiple strains of the influenza virus are often present within a population. It is a significant challenge for health care administrators to determine the most effective allocation of two different vaccines to combat the various strains when treating the public. We employ a mathematical model, a system of differential equations, to find a strategy for vaccinating a population in order to minimize the number of infected individuals. We consider various strengths of transmission of the disease, availability of vaccine doses, vaccination rates, and other model parameters. This research may lead to more effective health care …
Investigating Prerequisite Grade Requirements In The Calculus Sequence, Michelle Kleckner, Lexi Paradine, Katie Merkling, Mindy Capaldi
Investigating Prerequisite Grade Requirements In The Calculus Sequence, Michelle Kleckner, Lexi Paradine, Katie Merkling, Mindy Capaldi
Symposium on Research and Creative Expression (SORCE)
The Valparaiso University Mathematics and Computer Science Department has been debating a shift from a D- to a C- in the calculus sequence prerequisite grade requirement. We first researched policies at other colleges and universities. Next, we gathered data on students' self-predicted grades by distributing pre- and post-semester surveys and measuring the accuracy of the results in comparison to the actual grade data. Using the surveys, we also associated students' expectations with their majors. In the end, we investigated whether or not prerequisite grades can predict subsequent course performance. Statistical analysis of the past four years of math student data …
On The (Co)Homology Of Non-Commutative Toroidal Orbifold, Safdar Quddus
On The (Co)Homology Of Non-Commutative Toroidal Orbifold, Safdar Quddus
All Theses and Dissertations (ETDs)
Noncommutative torus algebra was studied in the early 80's as a fundamental example of noncommutative geometry. Connes calculated its cyclic and Hochschild cohomology. In this thesis, we study noncommutative toroidal orbifolds generated by actions of finite subgroups of S L(2,) on a noncommutative torus algebra.
In the first part, we calculate the Hochschild and cyclic homology of Γ for all finite subgroups Γ S L(2,). In the second part we analyse the cohomology of these algebras and compute the Chern-Connes pairing between the elements of and explicit cocycles discovered in our calculations. In the third part we discuss some …
A Perspective On Multiple Waves Of Influenza Pandemics, Anna Mummert, Howard Weiss, Li-Pong Long, Jose´ M. Amigo´, Xiu-Feng Wan
A Perspective On Multiple Waves Of Influenza Pandemics, Anna Mummert, Howard Weiss, Li-Pong Long, Jose´ M. Amigo´, Xiu-Feng Wan
Mathematics Faculty Research
Background: A striking characteristic of the past four influenza pandemic outbreaks in the United States has been the multiple waves of infections. However, the mechanisms responsible for the multiple waves of influenza or other acute infectious diseases are uncertain. Understanding these mechanisms could provide knowledge for health authorities to develop and implement prevention and control strategies. Materials and Methods: We exhibit five distinct mechanisms, each of which can generate two waves of infections for an acute infectious disease. The first two mechanisms capture changes in virus transmissibility and behavioral changes. The third mechanism involves population heterogeneity (e.g., demography, geography), where …
"Integration Of Math And Music In The Secondary Classroom", Brian O'Neill
"Integration Of Math And Music In The Secondary Classroom", Brian O'Neill
Honors Theses
The disciplines of mathematics and music seem worlds apart at first glance. Harmonious connections can inevitably be created if a deeper appreciation is lent to these stereotypically dissimilar subjects. "Integration of Mathematics and Music in the Secondary Classroom" is a quadratic function unit that utilizes music to aid in teaching mathematical concepts. The unit consists of a compilation of traditional rote mathematics and three main inquiry lessons: Problems Without Polyrhythm, Ma-Thematics, and The Undertones of Overtones. The unique approach of inquiry allows students to construct meaningful learning through a curriculum that is driven by their own mathematical questions. In addition, …
A Look At Multi-Decompositions Of Complete Graphs Into Graph Pairs Of Order 4, Yizhe Gao, Daniel Roberts, Faculty Advisor
A Look At Multi-Decompositions Of Complete Graphs Into Graph Pairs Of Order 4, Yizhe Gao, Daniel Roberts, Faculty Advisor
John Wesley Powell Student Research Conference
Firstly, a graph G consists of a vertex set V (G), and an edge set E (G) of endpoints which relate two vertices with each edge. Also, a decomposition of a graph is a list of subgraphs such that each edge appears in exactly one subgraph in the list. In the field ofgraph theory, graph decomposition is an active field of research. One type of decomposition is graph pairs. A graph pair is a pair of graphs on the same vertex set whose union is the complete graph. Abueida and Daven studieddecompositions of complete graphs into graph-pairs of order four. …
Frames And Spline Framelets, Tung Nguyen, Nahee Kim, Tian-Xiao He, Faculty Advisor
Frames And Spline Framelets, Tung Nguyen, Nahee Kim, Tian-Xiao He, Faculty Advisor
John Wesley Powell Student Research Conference
Frames can be seen as a generalization of orthonormal bases, which not only maintain useful characteristics of orthonormal bases but also allow more flexibility in applications. The applications of frames include communication and image processing, as its characteristic inherited from orthonormal bases helps speed up the transmitting and processing time while its additional flexibility adds to frames the ability to reconstruct lost information. In this project, we study the construction of a class of tight frames in Euclidean spaces. Also, we use Fourier transforms and the techniques of Multi-Resolution Analysis (MRA) in wavelet analysis to investigate a class of tight …