Association Of Workplace Chronic And Acute Stressors With Employee Weight Status: Data From Worksites In Turmoil,
2010
University of Rochester
Association Of Workplace Chronic And Acute Stressors With Employee Weight Status: Data From Worksites In Turmoil, Isabel Diana Fernandez, Haiyan Su, Paul C. Winters, Hua Liang
Department of Applied Mathematics and Statistics Faculty Scholarship and Creative Works
Objectives: To examine the independent and joint effects of psychosocial chronic and acute stressors with weight status and to report the intraclass correlation coefficient for body mass index (BMI). Methods: Baseline data on 2782 employees from a group-randomized weight gain prevention intervention were examined to investigate the effect of high job strain and job insecurity on BMI and on the odds of overweight/obesity including potential confounders and mediating variables. Data were analyzed using mixed models. Results: The mediating variables removed the effect of high job strain on weight (β = 0.68, P = 0.07; odds ratios = 1.34, confidence interval …
Parallel And Distributed Simulation Of Parabolic And Telegraphic Equations.,
2010
Universiti Malaya
Parallel And Distributed Simulation Of Parabolic And Telegraphic Equations., Ewedafe Simon Uzezi
Student Works (2010-2019)
In this thesis, a parallel implementation of explicit/implicit parallel algorithms such as the stationary iterative methods and the class of iterating alternating methods which includes: Alternating Direction Implicit (ADI), Iterative Alternating Direction Explicit (IADE), for D’Yakonov (IADE-DY), Double sweep Mitchell and Fairweather (MF-DS) and Alternating Group Explicit (AGE) method for solving 1-Dimensional (1-D), 2-Dimensional (2-D) Parabolic (special examples including 1-D, 2-D Bio-Heat Equation) and 1-D, 2-D and 3-D Telegraphic Equations on a distributed environment of Message Passing Interface (MPI) and Parallel Virtual Machine (PVM) platform is presented. To correlate the communication activity with computation, we counted events between significant MPI/PVM …
Laguerre Arc Length From Distance Functions,
2010
University of Michigan, Ann Arbor
Laguerre Arc Length From Distance Functions, David E. Barrett, Michael Bolt
University Faculty Publications and Creative Works
For the Laguerre geometry in the dual plane, invariant arc length is shown to arise naturally through the use of a pair of distance functions. These distances are useful for identifying equivalence classes of curves, within which the extremal curves are proved to be strict maximizers of Laguerre arc length among three-times differentiable curves of constant signature in a prescribed isotopy class. For smoother curves, it is shown that Laguerre curvature determines the distortion of the distance functions. These results extend existing work for the Möbius geometry in the complex plane. © 2010 International Press.
Fraction Competency And Algebra Success,
2010
Louisiana State University and Agricultural and Mechanical College
Fraction Competency And Algebra Success, Coretta Thomas
LSU Master's Theses
Abstract In this thesis, I investigated the importance of fraction competence to success in algebra. I studied 107 of the students whom I teach. These students were all enrolled in Algebra I. A fraction pretest and an algebra pretest were given at the beginning of the 2009-2010 school year. A comparison was done to study the connection between the fraction pretest score and the semester grade as well as the algebra pretest score and the semester grade. The strongest correlation was between the fraction pretest and the semester grade. This supported the theory that fraction competence is a strong predictor …
A Characterization Of Near Outer-Planar Graphs,
2010
Louisiana State University and Agricultural and Mechanical College
A Characterization Of Near Outer-Planar Graphs, Tanya Allen Lueder
LSU Master's Theses
This thesis focuses on graphs containing an edge whose removal results in an outer-planar graph. We present partial results towards the larger goal of describing the class of all such graphs in terms of a finite list of excluded graphs. Specifically, we give a complete description of those members of this list that are not 2-connected or do not contain a subdivision of a three-spoke wheel. We also show that no members of the list contain a five-spoke wheel.
Copula And Default Correlation,
2010
Louisiana State University and Agricultural and Mechanical College
Copula And Default Correlation, Dongxiang Yan
LSU Master's Theses
This work presents a study of copulas, with special focus on the Gaussian copula model and its behavior under a certain conditioning process. Simulations are carried out to examine the behavior of the moments on conditional copula model, as measured by the behavior of Wick identities which hold for multivariate Gaussians.
Closed-Form Solutions To Discrete-Time Portfolio Optimization Problems,
2010
Missouri University of Science and Technology
Closed-Form Solutions To Discrete-Time Portfolio Optimization Problems, Mathias Christian Goggel
Masters Theses
"In this work, we study some discrete time portfolio optimization problems. After a brief introduction of the corresponding continuous time models, we introduce the discrete time financial market model. The change in asset prices is modeled in contrast to the continuous time market by stochastic difference equations. We provide solutions for these stochastic difference equations. Then we introduce the discrete time risk-measure and the portfolio optimization problems. We provide closed form solutions to the discrete time problems. The main contribution of this thesis are the closed form solutions to the discrete time portfolio models. For simulation purposes the discrete time …
Perverse Poisson Sheaves On The Nilpotent Cone,
2010
Louisiana State University and Agricultural and Mechanical College
Perverse Poisson Sheaves On The Nilpotent Cone, Jared Lee Culbertson
LSU Doctoral Dissertations
For a reductive complex algebraic group, the associated nilpotent cone is the variety of nilpotent elements in the corresponding Lie algebra. Understanding the nilpotent cone is of central importance in representation theory. For example, the nilpotent cone plays a prominent role in classifying the representations of finite groups of Lie type. More recently, the nilpotent cone has been shown to have a close connection with the affine flag variety and this has been exploited in the Geometric Langlands Program. We make use of the following important fact. The nilpotent cone is invariant under the coadjoint action of G on the …
Method Of Riemann Surfaces In Modelling Of Cavitating Flow,
2010
Louisiana State University and Agricultural and Mechanical College
Method Of Riemann Surfaces In Modelling Of Cavitating Flow, Anna Zemlyanova
LSU Doctoral Dissertations
This dissertation is concerned with the applications of the Riemann-Hilbert problem on a hyperelliptic Riemann surface to problems on supercavitating flows of a liquid around objects. For a two-dimensional steady irrotational flow of liquid it is possible to introduce a complex potential w(z) which allows to apply the powerful methods of complex analysis to the solution of fluid mechanics problems. In this work problems on supercavitating flows of a liquid around one or two wedges have been stated. The Tulin single-spiral-vortex model is employed as a cavity closure condition. The flow domain is transformed into an auxiliary domain with known …
Power Series Expansions For Waves In High-Contrast Plasmonic Crystals,
2010
Louisiana State University and Agricultural and Mechanical College
Power Series Expansions For Waves In High-Contrast Plasmonic Crystals, Santiago Prado Parentes Fortes
LSU Doctoral Dissertations
In this thesis, a method is developed for obtaining convergent power series expansions for dispersion relations in two-dimensional periodic media with frequency dependent constitutive relations. The method is based on high-contrast expansions in the parameter _x0011_ = 2_x0019_d=_x0015_, where d is the period of the crystal cell and _x0015_ is the wavelength. The radii of convergence obtained are not too small, on the order of _x0011_ _x0019_ 102. That the method applies to frequency dependent media is an important fact, since the majority of the methods available in the literature are restricted to frequency independent constitutive relations. The convergent series …
Optimal Control And Nonlinear Programming,
2010
Louisiana State University and Agricultural and Mechanical College
Optimal Control And Nonlinear Programming, Qingxia Li
LSU Doctoral Dissertations
In this thesis, we have two distinct but related subjects: optimal control and nonlinear programming. In the first part of this thesis, we prove that the value function, propagated from initial or terminal costs, and constraints, in the form of a differential equation, satisfy a subgradient form of the Hamilton-Jacobi equation in which the Hamiltonian is measurable with respect to time. In the second part of this thesis, we first construct a concrete example to demonstrate conjugate duality theory in vector optimization as developed by Tanino. We also define the normal cones corresponding to Tanino's concept of the subgradient of …
Orthogonal Grassmannians And Hermitian K-Theory In A¹-Homotopy Theory Of Schemes,
2010
Louisiana State University and Agricultural and Mechanical College
Orthogonal Grassmannians And Hermitian K-Theory In A¹-Homotopy Theory Of Schemes, Girja Shanker Tripathi
LSU Doctoral Dissertations
In this work we prove that the hermitian K-theory is geometrically representable in the A^1 -homotopy category of smooth schemes over a field. We also study in detail a realization functor from the A^1 -homotopy category of smooth schemes over the field R of real numbers to the category of topological spaces. This functor is determined by taking the real points of a smooth R-scheme. There is another realization functor induced by taking the complex points with a similar description although we have not discussed this other functor in this dissertation. Using these realization functors we have concluded in brief …
Homogenization Of Nonlinear Partial Differential Equations,
2010
Louisiana State University and Agricultural and Mechanical College
Homogenization Of Nonlinear Partial Differential Equations, Silvia Jiménez
LSU Doctoral Dissertations
This dissertation is concerned with properties of local fields inside composites made from two materials with different power law behavior. This simple constitutive model is frequently used to describe several phenomena ranging from plasticity to optical nonlinearities in dielectric media. We provide the corrector theory for the strong approximation of fields inside composites made from two power law materials with different exponents. The correctors are used to develop bounds on the local singularity strength for gradient fields inside microstructured media. The bounds are multiscale in nature and can be used to measure the amplification of applied macroscopic fields by the …
Dimer Models For Knot Polynomials,
2010
Louisiana State University and Agricultural and Mechanical College
Dimer Models For Knot Polynomials, Moshe Cohen
LSU Doctoral Dissertations
A dimer model consists of all perfect matchings on a (bipartite) weighted signed graph, where the product of the signed weights of each perfect matching is summed to obtain an invariant. In this paper, the construction of such a graph from a knot diagram is given to obtain the Alexander polynomial. This is further extended to a more complicated graph to obtain the twisted Alexander polynomial, which involved "twisting" by a representation. The space of all representations of a given knot complement into the general linear group of a fixed size can be described by the same graph. This work …
Multigrid Methods For Maxwell's Equations,
2010
Louisiana State University and Agricultural and Mechanical College
Multigrid Methods For Maxwell's Equations, Jintao Cui
LSU Doctoral Dissertations
In this work we study finite element methods for two-dimensional Maxwell's equations and their solutions by multigrid algorithms. We begin with a brief survey of finite element methods for Maxwell's equations. Then we review the related fundamentals, such as Sobolev spaces, elliptic regularity results, graded meshes, finite element methods for second order problems, and multigrid algorithms. In Chapter 3, we study two types of nonconforming finite element methods on graded meshes for a two-dimensional curl-curl and grad-div problem that appears in electromagnetics. The first method is based on a discretization using weakly continuous P1 vector fields. The second method uses …
High Accuracy Multiscale Multigrid Computation For Partial Differential Equations,
2010
University of Kentucky
High Accuracy Multiscale Multigrid Computation For Partial Differential Equations, Yin Wang
University of Kentucky Doctoral Dissertations
Scientific computing and computer simulation play an increasingly important role in scientific investigation and engineering designs, supplementing traditional experiments, such as in automotive crash studies, global climate change, ocean modeling, medical imaging, and nuclear weapons. The numerical simulation is much cheaper than experimentation for these application areas and it can be used as the third way of science discovery beyond the experimental and theoretical analysis. However, the increasing demand of high resolution solutions of the Partial Differential Equations (PDEs) with less computational time has increased the importance for researchers and engineers to come up with efficient and scalable computational techniques …
Subgroups Of The Torelli Group,
2010
Louisiana State University and Agricultural and Mechanical College
Subgroups Of The Torelli Group, Leah R. Childers
LSU Doctoral Dissertations
Let Mod(Sg) be the mapping class group of an orientable surface of genus g, Sg. The action of Mod(Sg) on the homology of Sg induces the well-known symplectic representation:
Mod(Sg) ---> Sp(2g, Z).
The kernel of this representation is called the Torelli group, I(Sg).
We will study two subgroups of I(Sg). First we will look at the subgroup generated by all SIP-maps, SIP(Sg). We will show SIP(Sg) is not I(Sg) and is in fact an infinite index subgroup of I(Sg). We will also classify which SIP-maps are in the kernel of the Johnson homomorphism and Birman-Craggs-Johnson homomorphism.
Then we will …
Primes Of The Form X² + Ny² In Function Fields,
2010
Louisiana State University and Agricultural and Mechanical College
Primes Of The Form X² + Ny² In Function Fields, Piotr Maciak
LSU Doctoral Dissertations
Let n be a square-free polynomial over F_q, where q is an odd prime power. In this work, we determine which irreducible polynomials p in F_q[x] can be represented in the form X^2+nY^2 with X, Y in F_q[x]. We restrict ourselves to the case where X^2+nY^2 is anisotropic at infinity. As in the classical case over Z, the representability of p by the quadratic form X^2+nY^2 is governed by conditions coming from class field theory. A necessary and almost sufficient condition is that the ideal generated by p splits completely in the Hilbert class field H of K=F_q(x,sqrt(-n)) for the …
Hamilton-Jacobi Theory For Optimal Control Problems On Stratified Domains,
2010
Louisiana State University and Agricultural and Mechanical College
Hamilton-Jacobi Theory For Optimal Control Problems On Stratified Domains, Richard Charles Barnard
LSU Doctoral Dissertations
This thesis studies optimal control problems on stratified domains. We first establish a known proximal Hamilton-Jacobi characterization of the value function for problems with Lipschitz dynamics. This background gives the motivation for our results for systems over stratified domains, which is a system with non-Lipschitz dynamics that were introduced by Bressan and Hong. We provide an example that shows their attempt to derive a Hamilton-Jacobi characterization of the value function is incorrect, and discuss the nature of their error. A new construction of a multifunction is introduced that possesses properties similar to those of a Lipschitz multifunction, and is used …
Multiresolution Inverse Wavelet Reconstruction From A Fourier Partial Sum,
2010
CUNY Kingsborough Community College
Multiresolution Inverse Wavelet Reconstruction From A Fourier Partial Sum, Nataniel Greene
Publications and Research
The Gibbs phenomenon refers to the lack of uniform convergence which occurs in many orthogonal basis approximations to piecewise smooth functions. This lack of uniform convergence manifests itself in spurious oscillations near the points of discontinuity and a low order of convergence away from the discontinuities.In previous work [11,12] we described a numerical procedure for overcoming the Gibbs phenomenon called the Inverse Wavelet Reconstruction method (IWR). The method takes the Fourier coefficients of an oscillatory partial sum and uses them to construct the wavelet coefficients of a non-oscillatory wavelet series. However, we only described the method standard wavelet series and …
