Sökning: "Hamiltonian methods"

Visar resultat 1 - 5 av 44 avhandlingar innehållade orden Hamiltonian methods.

1. 1. Wave interactions by Hamiltonian methods

   Författare :Krister Wiklund; Umeå universitet; []
   Nyckelord :Hamiltonian formulation; wave interaction; stability; variational principles;

   Sammanfattning : This thesis is devoted to the description of fluids and gases from a Hamiltonian point of view. The method we apply is a development of the theory invented by Hamilton (1805-1865). The original formulation is restricted to a certain family of dynamical variables; the canonical variables. LÄS MER

3. 2. Symplectic methods for Hamiltonian isospectral flows and 2D incompressible Euler equations on a sphere

   Författare :Milo Viviani; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Fluid dynamics; Symplectic methods; Isospectral flows; Geometric integration; Hamiltonian systems; Structure preserving algorithms; Euler equations; Lie–Possion systems; Fluid dynamics.;

   Sammanfattning : The numerical solution of non-canonical Hamiltonian systems is an active and still growing field of research. At the present time, the biggest challenges concern the realization of structure preserving algorithms for differential equations on infinite dimensional manifolds. Several classical PDEs can indeed be set in this framework. LÄS MER

4. 3. Symplectic methods for isospectral flows and 2D ideal hydrodynamics

   Författare :Milo Viviani; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Symplectic methods; Fluid dynamics; Integrability theory; Euler equations; Lie--Possion systems; Isospectral flows; Geometric integration; Structure preserving algorithms; Hamiltonian systems;

   Sammanfattning : The numerical solution of non-canonical Hamiltonian systems is an active and still growing field of research. At the present time, the biggest challenges concern the realization of structure preserving algorithms for differential equations on infinite dimensional manifolds. LÄS MER

5. 4. Cosmological Models and Singularities in General Relativity

   Författare :Patrik Sandin; Claes Uggla; Alan Coley; Karlstads universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; general relativity; Bianchi cosmology; singularities; dynamical systems; Fuchsian methods; Hamiltonian methods; Theory of relativity; gravitation; Relativitetsteori; gravitation; Physics; Fysik;

   Sammanfattning : This is a thesis on general relativity. It analyzes dynamical properties of Einstein's field equations in cosmology and in the vicinity of spacetime singularities in a number of different situations. LÄS MER

7. 5. Analysis of Adaptive Finite Element Methods

   Författare :Mats G Larson; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : This thesis is concerned with the analysis and design of adaptive finite element methods for a variety of differential equations in mechanics and physics, including linear and semilinear elliptic equations, eigenvalue problems, the stationary Navier-Stokes equations, and Hamiltonian systems. The analysis focuses on sharp a posteriori error estimates, sharp a priori error estimates, stability properties, and the design of adaptive algorithms. LÄS MER