Search for dissertations about: "eigenvalue computation"

Showing result 1 - 5 of 12 swedish dissertations containing the words eigenvalue computation.

2. 1. Algorithms and Library Software for Periodic and Parallel Eigenvalue Reordering and Sylvester-Type Matrix Equations with Condition Estimation

   Author : Robert Granat; Bo Kågström; Isak Jonsson; Volker Mehrmann; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; periodic eigenvalue problems; product eigenvalue problems; periodic Schur form; periodic eigenvalue reordering; periodic eigenspaces; parallel algorithms; Sylvester-type matrix equations; parallel eigenvalue reordering; condition estimation; Computer science; Datavetenskap;

   Abstract : This Thesis contains contributions in two different but closely related subfields of Scientific and Parallel Computing which arise in the context of various eigenvalue problems: periodic and parallel eigenvalue reordering and parallel algorithms for Sylvestertype matrix equations with applications in condition estimation.Many real world phenomena behave periodically, e. READ MORE

4. 2. 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

5. 3. Krylov methods for nonlinear eigenvalue problems and matrix equations

   Author : Giampaolo Mele; Elias Jarlebring; Raf Vandebril; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Numerical Analysis; Numerisk analys;

   Abstract : Nonlinear eigenvalue problems (NEPs) arise in many fields of science and engineering. Such problems are often defined by large matrices, which have specific structures, such as being sparse, low-rank, etc. Like the linear eigenvalue problem, the eigenvector appears in a linear form, whereas the eigenvalue appears in a nonlinear form. READ MORE

6. 4. The Dirac Equation: Numerical and Asymptotic Analysis

   Author : Hasan Almanasreh; Göteborgs universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Dirac operator; eigenvalue problem; finite element method; spurious eigenvalues; Petrov-Galerkin; cubic Hermite basis functions; stability parameter; meshfree method; $hp$-cloud; intrinsic enrichment; G-convergence; $ Gamma$-convergence; scattering theory; identification; wave operator; stationary approach; Dirac operator;

   Abstract : The thesis consists of three parts, although each part belongs to a specific subject area in mathematics, they are considered as subfields of the perturbation theory. The main objective of the presented work is the study of the Dirac operator; the first part concerns the treatment of the spurious eigenvalues in the computation of the discrete spectrum. READ MORE

7. 5. Eigenfrequency Analysis FE-Adaptivity and a Nonlinear Eigenproblem Algorithm

   Author : Patrik Hager; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nonlinear eigenvalue; finite element; adaptivity; superconvergent patch recovery; rational krylov;

   Abstract : Engineering often pose the problem of computing the frequencies with which a system oscillates and the corresponding displacement patterns the system forms, and in case damping is present then the rates of which the amplitudes of the displacement patterns decay are also required. It is necessary to compute these quantities within a prescribed accuracy and the effort required for the computations should be minimised. READ MORE