Sökning: "Saddle point matrix"
Visar resultat 1 - 5 av 7 avhandlingar innehållade orden Saddle point matrix.
1. Exact Results in Five-Dimensional Gauge Theories : On Supersymmetry, Localization and Matrix Models
Sammanfattning : Gauge theories are one of the corner stones of modern theoretical physics. They describe the nature of all fundamental interactions and have been applied in multiple branches of physics. The most challenging problem of gauge theories, which has not been solved yet, is their strong coupling dynamics. LÄS MER
2. Analysis and Implementation of Preconditioners for Prestressed Elasticity Problems : Advances and Enhancements
Sammanfattning : In this work, prestressed elasticity problem as a model of the so-called glacial isostatic adjustment (GIA) process is studied. The model problem is described by a set of partial differential equations (PDE) and discretized with a mixed finite element (FE) formulation. LÄS MER
3. Robust Preconditioners Based on the Finite Element Framework
Sammanfattning : Robust preconditioners on block-triangular and block-factorized form for three types of linear systems of two-by-two block form are studied in this thesis. The first type of linear systems, which are dense, arise from a boundary element type of discretization of crack propagation problems. LÄS MER
4. Computational Techniques for Coupled Flow-Transport Problems
Sammanfattning : This thesis presents numerical techniques for solving problems of incompressible flow coupled to scalar transport equations using finite element discretizations in space. The two applications considered in this thesis are multi-phase flow, modeled by level set or phase field methods, and planetary mantle convection based on the Boussinesq approximation. LÄS MER
5. Robust preconditioning methods for algebraic problems, arising in multi-phase flow models
Sammanfattning : The aim of the project is to construct, analyse and implement fast and reliable numerical solution methods to simulate multi-phase flow, modeled by a coupled system consisting of the time-dependent Cahn-Hilliard and incompressible Navier-Stokes equations with variable viscosity and variable density. This thesis mainly discusses the efficient solution methods for the latter equations aiming at constructing preconditioners, which are numerically and computationally efficient, and robust with respect to various problem, discretization and method parameters. LÄS MER