Sökning: "eigenvalue problem"

Visar resultat 1 - 5 av 52 avhandlingar innehållade orden eigenvalue problem.

  1. 1. The Dirac Equation: Numerical and Asymptotic Analysis

    Författare :Hasan Almanasreh; Göteborgs universitet.; Gothenburg University.; [2012]
    Nyckelord :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; meshfree method; $hp$-cloud; stability parameter; cubic Hermite basis functions; scattering theory; intrinsic enrichment; identification; spurious eigenvalues; wave operator; finite element method; $ Gamma$-convergence; eigenvalue problem; stationary approach; Petrov-Galerkin; G-convergence;

    Sammanfattning : 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. LÄS MER

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

    Detta är en avhandling från Stockholm : Universitetsservice US AB

    Författare :Jan Dufek; Jan Wallenius; Waclaw Gudowski; Cheikh Diop; [2009]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Monte Carlo; reactor physics; fission source; inactive cycles; convergence; burnup; steady-state; criticality; eigenvalue; NATURAL SCIENCES Physics Nuclear physics; NATURVETENSKAP Fysik Kärnfysik;

    Sammanfattning : 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. LÄS MER

  3. 3. Some numerical and analytical methods for equations of wave propagation and kinetic theory

    Detta är en avhandling från Karlstad : Karlstads universitet

    Författare :Eva Mossberg; Alexander Bobylev; Giovanni Russo; [2008]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; wave propagation; finite difference metods high order methods; Landau-Fokker-Planck equation; Monte-Carlo simulations; Boltzmann equation; hard sphere model; eigenvalue problem; MATHEMATICS; MATEMATIK; Matematik; Mathematics;

    Sammanfattning : This thesis consists of two different parts, related to two different fields in mathematical physics: wave propagation and kinetic theory of gases. Various mathematical and computational problems for equations from these areas are treated. LÄS MER

  4. 4. Some new results concerning general weighted regular Sturm-Liouville problems

    Detta är en avhandling från Luleå : Luleå University of Technology

    Författare :Mervis Kikonko; Lars-Erik Persson; Peter Wall; Angelo B. Mingarelli; Alexey Karapetyants; [2016]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Partial differential equations; Sturm-Liouville problem; Right-definite; left-definite; non-definite; indefinite; Dirichlet problem; spectrum; eigenvalues; non-real eigenvalues; Richardson number; Richardson index; turning point; Mathematics; Matematik;

    Sammanfattning : In this PhD thesis we study some weighted regular Sturm-Liouville problems in which the weight function takes on both positive and negative signs in an appropriate interval [a,b]. With such  problems there is the possible existence of non-real eigenvalues, unlike in the definite case (i.e. LÄS MER

  5. 5. Parallel Algorithms and Library Software for the Generalized Eigenvalue Problem on Distributed Memory Computer Systems

    Detta är en avhandling från Umeå : Umeå universitet

    Författare :Björn Adlerborn; Bo Kågström; [2016]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; computer and systems sciences; data- och systemvetenskap;

    Sammanfattning : We present and discuss algorithms and library software for solving the generalized non-symmetric eigenvalue problem (GNEP) on high performance computing (HPC) platforms with distributed memory. Such problems occur frequently in computational science and engineering, and our contributions make it possible to solve GNEPs fast and accurate in parallel using state-of-the-art HPC systems. LÄS MER