Sökning: "Variational method"

Visar resultat 1 - 5 av 56 avhandlingar innehållade orden Variational method.

  1. 1. Adaptive variational multiscale methods

    Detta är en avhandling från Göteborg : Chalmers University of Technology

    Författare :Axel Målqvist; Göteborgs universitet.; Gothenburg University.; [2005]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; finite element method; Galerkin; duality; a posteriori error estimation; adaptivity; variational multiscale method; mixed formulation; multi-physics; oil reservoir simulation;

    Sammanfattning : In this thesis we present a new adaptive multiscale method for solving elliptic partial differential equations. The method is based on numerical solution of decoupled local fine scale problems on patches. LÄS MER

  2. 2. Adaptive Finite Element Methods for Optimal Control Problems

    Detta är en avhandling från Göteborg : Chalmers University of Technology

    Författare :Karin Kraft; Göteborgs universitet.; Gothenburg University.; [2011]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; finite element method; discontinuous Galerkin method; optimal control; a posteriori error estimate; dual weighted residual; adaptive; multilevel algorithm; Newton method; control constraint; variational inequality; vehicle dynamics.;

    Sammanfattning : In this thesis we study the numerical solution of optimal control problems. The problems considered consist of a systemof differential equations, the state equations, which are governed bya control variable. The goal is to determine the states and controls which minimize a given cost functional. LÄS MER

  3. 3. Some Applications of Variational Inequalities in Mathematical Finance and Numerics

    Detta är en avhandling från Centre for Mathematical Sciences, Lund University

    Författare :Martin Dahlgren; Lunds universitet.; Lund University.; [2005]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Matematik; Mathematics; HJB quasi variational inequalities; option pricing; Impulse control; parabolic PDE; finite element method; Galerkin method;

    Sammanfattning : This thesis contains two parts. The first part deals with a stochastic impulse control problem, subject to the restriction of a minimum time lapse in between interventions made by the controller. We prove existence of an optimal control and show that the value function of the control problem satisfies a system of quasi-variational inequalities. LÄS MER

  4. 4. Ghosts and machines regularized variational methods for interactive simulations of multibodies with dry frictional contacts

    Detta är en avhandling från Umeå : Datavetenskap

    Författare :Claude Lacoursière; Umeå universitet.; [2007]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Discrete mechanics; Variational method; Contact problems; Impacts; Least action principle; Saddle point problems; Lagrange Multipliers; Constrained systems; Multibody Systems; Numerical regularization; Constraint realization; Constraint stabilization; Dry friction; Differential Algebraic Equations; Nonsmooth problems; Linear Complementarity; Quaternion algebra; Numerical linear algebra; Physics modeling; Interactive simulation; Numerical stability; Rigid body dynamics; Dissipative systems; NATURAL SCIENCES Physics Other physics Computational physics; NATURVETENSKAP Fysik Övrig fysik Beräkningsfysik;

    Sammanfattning : A time-discrete formulation of the variational principle of mechanics is used to provide a consistent theoretical framework for the construction and analysis of low order integration methods. These are applied to mechanical systems subject to mixed constraints and dry frictional contacts and impacts---machines. LÄS MER

  5. 5. On adaptive finite element methods based on a posteriori estimates

    Detta är en avhandling från Göteborg : Chalmers University of Technology

    Författare :Axel Målqvist; Göteborgs universitet.; Gothenburg University.; [2004]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; finite element method; Galerkin; duality; a posteriori error estimation; adaptivity; Poisson equation; boundary penalty method; Helmholtz equation; pollution; variational multiscale method;

    Sammanfattning : .... LÄS MER