Search for dissertations about: "Parabolic equation"

Showing result 16 - 20 of 56 swedish dissertations containing the words Parabolic equation.

  2. 16. Generalized finite element methods for time-dependent multiscale problems

    Author : Per Ljung; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; localized orthogonal decomposition; multiscale; Strongly damped wave equation; parabolic equations.; finite element method;

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

  4. 17. The Influence of Atmospheric Turbulence on Barrier Sound Reduction

    Author : Jens Forssén; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; traffic noise; barrier; measurements; turbulence; scattering cross-section; substitute sources; outdoor sound propagation; parabolic equation method; random media; numerical modelling;

    Abstract : Numerical modelling and measurements are used for studying the reduced performance of a noise barrier, caused by a turbulent atmosphere. The turbulence scatters the sound, which leads to an increased noise level in the acoustic shadow region behind the barrier. READ MORE

  5. 18. Some special problems in elliptic and parabolic variational inequalities

    Author : Gulchehra Kulieva; Luleå tekniska universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Matematik; Mathematics;

    Abstract : This Licentiate Thesis is devoted above all to the investigation of variational inequalities. Chapter 1 deals with linear elliptic variational inequalities, where the operator is degenerated or singular, which involves the use of some weighted Sobolev spaces. READ MORE

  6. 19. Numerical Solution of Ill-posed Cauchy Problems for Parabolic Equations

    Author : Zohreh Ranjbar; Lars Eldén; Per Christian Hansen; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; MATHEMATICS; MATEMATIK;

    Abstract : Ill-posed mathematical problem occur in many interesting scientific and engineering applications. The solution of such a problem, if it exists, may not depend continuously on the observed data. For computing a stable approximate solution it is necessary to apply a regularization method. READ MORE

  7. 20. Variational Methods for Moments of Solutions to Stochastic Differential Equations

    Author : Kristin Kirchner; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Additive and multiplicative noise; Stochastic partial differential equation; Projective and injective tensor product space; Hilbert tensor product space; Space-time variational problem; Petrov-Galerkin discretization; Stochastic ordinary differential equation;

    Abstract : Numerical methods for stochastic differential equations typically estimate moments of the solution from sampled paths. Instead, we pursue the approach proposed by A. Lang, S. Larsson, and Ch. READ MORE