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Showing result 1 - 5 of 50 swedish dissertations matching the above criteria.

2. 1. Multiparameter eigenvalue problems

   Author : Anders Källström; Uppsala universitet; []
   Keywords : NATURAL SCIENCES; NATURVETENSKAP;

   Abstract : .... READ MORE

4. 2. 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

5. 3. Numerical methods for Sylvester-type matrix equations and nonlinear eigenvalue problems

   Author : Emil Ringh; Elias Jarlebring; Johan Karlsson; Per Enqvist; Daniel Kressner; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Matrix equations; Lyapunov equation; Sylvester equation; nonlinear eigenvalue problems; two-parameter eigenvalue problems; Krylov methods; iterative methods; preconditioning; projection methods; Matrisekvationer; Lyapunovekvationen; Sylvesterekvationen; ickelinjära egenvärdesproblem; två-parameters egenvärdesproblem; Krylovmetoder; iterativa metoder; förkonditionering; projektionsmetoder; Tillämpad matematik och beräkningsmatematik; Applied and Computational Mathematics; Optimization and Systems Theory; Optimeringslära och systemteori; Numerical Analysis; Numerisk analys;

   Abstract : Linear matrix equations and nonlinear eigenvalue problems (NEP) appear in a wide variety of applications in science and engineering. Important special cases of the former are the Lyapunov equation, the Sylvester equation, and their respective generalizations. These appear, e.g. READ MORE

6. 4. Development of New Monte Carlo Methods in Reactor Physics : Criticality, Non-Linear Steady-State and Burnup Problems

   Author : Jan Dufek; Jan Wallenius; Waclaw Gudowski; Cheikh Diop; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Monte Carlo; reactor physics; fission source; inactive cycles; convergence; burnup; steady-state; criticality; eigenvalue; Nuclear physics; Kärnfysik;

   Abstract : The Monte Carlo method is, practically, the only approach capable of giving detail insight into complex neutron transport problems. In reactor physics, the method has been used mainly for determining the keff in criticality calculations. READ MORE

7. 5. Reliable hp finite element computations of scattering resonances in nano optics

   Author : Juan Carlos Araujo-Cabarcas; Christian Engström; David Cohen; Mats G. Larson; Jeffrey Ovall; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Scattering resonances; Helmholtz problems; pseudospectrum; Lippmann-Schwinger equation; finite element methods; nonlinear eigenvalue problems; spurious solutions;

   Abstract : Eigenfrequencies are commonly studied in wave propagation problems, as they are important in the analysis of closed cavities such as a microwave oven. For open systems, energy leaks into infinity and therefore scattering resonances are used instead of eigenfrequencies. READ MORE