Search for dissertations about: "partial operator"

Showing result 1 - 5 of 67 swedish dissertations containing the words partial operator.

  2. 1. Infinite dimensional holomorphy in the ring of formal power series : partial differential operators

    Author : Henrik Petersson; Andrei Khrennikov; Sean Dineen; Växjö universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Infinite dimensional holomorphy; Formal power series; Fourier-Borel transform; Paley-Wiener theorem; Fischer decomposition; Fischer pair; Fock space; Cauchy-Problem; Kergin operator; PDE-preserving; Pseudo-differential operators.; MATHEMATICS; MATEMATIK;

    Abstract : We study holomorphy in the ring of formal power series in an infinite number of variables. Thus we restrict our study to (infinite dimensional) holomorphy on sequence spaces and we show that we obtain a rich theory without requiring any topological structure on the domain space. We make a comprehensive PDO-study for the spaces under consideration. READ MORE

  4. 2. Approximating Stochastic Partial Differential Equations with Finite Elements: Computation and Analysis

    Author : Andreas Petersson; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Lévy process; Lyapunov equation; white noise; finite element method; multilevel Monte Carlo; Monte Carlo; multiplicative noise; asymptotic mean square stability; stochastic heat equation; covariance operator; weak convergence; generalized Wiener process; numerical approximation; stochastic wave equation; Stochastic partial differential equations;

    Abstract : Stochastic partial differential equations (SPDE) must be approximated in space and time to allow for the simulation of their solutions. In this thesis fully discrete approximations of such equations are considered, with an emphasis on finite element methods combined with rational semigroup approximations. READ MORE

  5. 3. Selected Topics in Partial Differential Equations

    Author : Mattias Enstedt; Michael Melgaard; William Desmond Evans; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; MATHEMATICS; MATEMATIK; Applied mathematics; Tillämpad matematik;

    Abstract : This Ph.D. thesis consists of five papers and an introduction to the main topics of the thesis. In Paper I we give an abstract criteria for existence of multiple solutions to nonlinear coupled equations involving magnetic Schrödinger operators. READ MORE

  6. 4. Numerical Approximation of Solutions to Stochastic Partial Differential Equations and Their Moments

    Author : Kristin Kirchner; Göteborgs universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Petrov– Galerkin discretizations; Strong and weak convergence; Fractional operators; Finite element methods; Space-time variational problems; Tensor product spaces; Stochastic partial differential equations; White noise; Petrov– Galerkin discretizations;

    Abstract : The first part of this thesis focusses on the numerical approximation of the first two moments of solutions to parabolic stochastic partial differential equations (SPDEs) with additive or multiplicative noise. More precisely, in Paper I an earlier result (A. Lang, S. Larsson, and Ch. READ MORE

  7. 5. On weak and strong convergence of numerical approximations of stochastic partial differential equations

    Author : Fredrik Lindgren; Göteborgs universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Additive noise; Cahn-Hilliard-Cook equation; Error estimate; Finite element; Hyperbolic equation; Parabolic equation; Rational approximation; Stochastic partial differential equation; Strong convergence; Truncation; Wiener process; Weak convergence; Weak convergence;

    Abstract : This thesis is concerned with numerical approximation of linear stochastic partial differential equations driven by additive noise. In the first part, we develop a framework for the analysis of weak convergence and within this framework we analyze the stochastic heat equation, the stochastic wave equation, and the linearized stochastic Cahn-Hilliard, or the linearized Cahn-Hilliard-Cook equation. READ MORE