Sökning: "evolution equations"

Visar resultat 1 - 5 av 124 avhandlingar innehållade orden evolution equations.

  1. 1. Discretizations of nonlinear dissipative evolution equations. Order and convergence

    Författare :Eskil Hansen; Numerisk analys; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; kontroll; systems; numerisk analys; control; Datalogi; numerical analysis; Computer science; B-convergence; Dissipative maps; Logarithmic Lipschitz constants; Galerkin methods; Nonlinear evolution equations; Time discretizations; system;

    Sammanfattning : The theme of this thesis is to study discretizations of nonlinear dissipative evolution equations, which arise in e.g. advection-diffusion-reaction processes. LÄS MER

  3. 2. Multiscale methods for evolution problems

    Författare :Per Ljung; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; localized orthogonal decomposition; multiscale; stochastic partial differential equations; Strongly damped wave equation; finite element method; spatial network models; parabolic equations;

    Sammanfattning : In this thesis we develop and analyze generalized finite element methods for time-dependent partial differential equations (PDEs). The focus lies on equations with rapidly varying coefficients, for which the classical finite element method is insufficient, as it requires a mesh fine enough to resolve the data. LÄS MER

  4. 3. Numerical Analysis of Evolution Problems in Multiphysics

    Författare :Anna Persson; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; regularity; generalized finite element; localized orthogonal decomposition; multiscale; finite element method; Thermoelasticity; Riccati equations; thermistor; linear elasticity; Joule heating; parabolic equations; Regularity; generalized finite element; localized orthogonal decomposition; multiscale finite element method; Thermoelasticity; Riccati equations; thermistor; linear elasticity; Joule heating; parabolic equations;

    Sammanfattning : In this thesis we study numerical methods for evolution problems in multiphysics. The term multiphysics is commonly used to describe physical phenomena that involve several interacting models. Typically, such problems result in coupled systems of partial differential equations. LÄS MER

  5. 4. On weak convergence, Malliavin calculus and Kolmogorov equations in infinite dimensions

    Författare :Adam Andersson; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Stochastic evolution equations; stochastic Volterra equations; weak approximation; Kolmogorov equations in infinite dimensions; Malliavin calculus; finite element method; backward Euler method; Kolmogorov equations in infinite dimensions;

    Sammanfattning : This thesis is focused around weak convergence analysis of approximations of stochastic evolution equations in Hilbert space. This is a class of problems, which is sufficiently challenging to motivate new theoretical developments in stochastic analysis. LÄS MER

  7. 5. Evolution of Ecological Communities in Spatially Heterogeneous Environments

    Författare :Jonas Wickman; Åke Brännström; Sebastian Diehl; Mathew A Leibold; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Spatial models; reaction-diffusion equations; eco-evolutionary models; adaptive dynamics; evolutionarily stable communities;

    Sammanfattning : Evolutionarily stable communities are the endpoints of evolution, and ecological communities whose traits are under selection will eventually settle into them. Hence, the properties of such communities are of particular interest, as they can persist over long evolutionary time scales. LÄS MER