Search for dissertations about: "Krylov space methods"

Showing result 1 - 5 of 9 swedish dissertations containing the words Krylov space methods.

2. 1. Numerical Methods for Wave Propagation : Analysis and Applications in Quantum Dynamics

   Author : Emil Kieri; Sverker Holmgren; Vasile Gradinaru; Hans O. Karlsson; Tobias Jahnke; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; computational wave propagation; quantum dynamics; time-dependent Schrödinger equation; spectral methods; Gaussian beams; splitting methods; low-rank approximation; Scientific Computing; Beräkningsvetenskap;

   Abstract : We study numerical methods for time-dependent partial differential equations describing wave propagation, primarily applied to problems in quantum dynamics governed by the time-dependent Schrödinger equation (TDSE). We consider both methods for spatial approximation and for time stepping. READ MORE

4. 2. Numerical methods for parameterized linear systems

   Author : Siobhán Correnty; Elias Jarlebring; Johan Karlsson; Kirk M. Soodhalter; Andrew J. Wathen; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Parameterized linear systems; Krylov subspace methods; preconditioning; tensor decompositions; shifted linear systems; parameterized partial differential equations; time-delay systems; transfer functions; parameter estimation problems; Parameteriserade linjära system; Krylov-metoder; förkonditionering; tensordekomposition; skiftade linjära system; parametriserade partiella differentialekvationer; tidsfördröjningssystem; överföringsfunktioner; parameteruppskattningsproblem; Numerical Analysis; Numerisk analys;

   Abstract : Solving linear systems of equations is a fundamental problem in engineering. Moreover, applications involving the solution to linear systems arise in the social sciences, business, and economics. Specifically, the research conducted in this dissertation explores solutions to linear systems where the system matrix depends nonlinearly on a parameter. READ MORE

5. 3. Model Order Reduction with Rational Krylov Methods

   Author : K. Henrik A. Olsson; Axel Ruhe; Volker Mehrmann; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Model order reduction; dual rational Arnoldi; rational Krylov; moment matching; eigenvalue computation; stability analysis; heat exchanger model; Numerical analysis; Numerisk analys;

   Abstract : Rational Krylov methods for model order reduction are studied. A dual rational Arnoldi method for model order reduction and a rational Krylov method for model order reduction and eigenvalue computation have been implemented. It is shown how to deflate redundant or unwanted vectors and how to obtain moment matching. READ MORE

6. 4. Information Retrieval Using Krylov Subspace Methods

   Author : Katarina Blom; Göteborgs universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES;

   Abstract : In this dissertation we discuss how simple Krylov subspace methods can be used for information retrieval (IR). The dissertation consists of two parts. The first part gives a background of IR and introduces the vector space model for IR and the Krylov subspace methods that we use. The second part consists of four articles. READ MORE

7. 5. Efficient Solvers for Space-Time Discontinuous Galerkin Spectral Element Methods

   Author : Lea Miko Versbach; Numerisk analys; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Discontinuous Galerkin Method; Spectral Element Method; Finite Volume Method; Implicit Schemes; Preconditioner; Multigrid Method; Space-Time; Lobatto IIIC Method; Local Fourier Analysis;

   Abstract : In this thesis we study efficient solvers for space-time discontinuous Galerkin spectral element methods (DG-SEM). These discretizations result in fully implicit schemes of variable order in both spatial and temporal directions. READ MORE