Search for dissertations about: "well equation"

Showing result 1 - 5 of 574 swedish dissertations containing the words well equation.

  2. 1. 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

  4. 2. Symmetries and conservation laws

    Author : Raisa Khamitova; Börje Nilsson; Claes Jougréus; Maria Luz Gandarias; Växjö universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; conservation law; Noether s theorem; Lie group analysis; Lie-Bäcklund transformations; basis of conservation laws; formal Lagrangian; self-adjoint equation; quasi-selfadjoint; equation; nonlocal conservation law; Mathematical physics; Matematisk fysik;

    Abstract : Conservation laws play an important role in science. The aim of this thesis is to provide an overview and develop new methods for constructing conservation laws using Lie group theory. The derivation of conservation laws for invariant variational problems is based on Noether’s theorem. READ MORE

  5. 3. 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

  6. 4. Subjective Well-Being in Swedish Women

    Author : Daiva Daukantaitė; Lars R. Bergman; Katariina Salmela-Aro; Stockholms universitet; []
    Keywords : SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; women; subjective well-being; longitudinal; cluster analysis; social circumstances; personality; Psychology; Psykologi;

    Abstract : The present thesis concerns middle-aged women’s subjective well-being (SWB). The interest is focused on the importance of childhood factors, social circumstances, and personality for middle-aged women’s general SWB. READ MORE

  7. 5. Macroscopic Volume and Free Volume of Polymer Blends and Pressure-densified Polymers

    Author : Marcus Schmidt; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; free-volume theories; refractive index; Lorentz-Lorenz equation; loss tangent; Avrami equation; freezing fractions; copolymers; polymer blends; pressure dilatometry; Tait equation of state; free-volume distributions; pressure-densified polymers; entropy of melting; dynamic-mechanical analysis; positronium; positron annihilation; free volume; cavity size; polymers; bulk modulus; PVT; phase separation; compressibility; thermal expansivity;

    Abstract : The macroscopic volume V as a function of pressure P and temperature T is obtained from PVT measurements. PVT data is sensitive to the state of polymers and changes therein. Moreover, PVT data gives access to the free-volume fraction. READ MORE