Search for dissertations about: "approximate solutions to systems of linear equations"

Showing result 1 - 5 of 13 swedish dissertations containing the words approximate solutions to systems of linear equations.

  2. 1. Approaches to accelerate methods for solving systems of equations arising in nonlinear optimization

    Author : David Ek; Anders Forsgren; Jacek Gondzio; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Nonlinear optimization; mathematical programming; interior-point methods; approximate solutions to systems of linear equations; method of conjugate gradients; quasi-Newton methods; modified Newton methods; Ickelinjär optimering; matematisk programmering; inre-punktsmetoder; approximativa lösningar till linjära ekvationssystem; konjugerade gradientmetoden; kvasi-Newtonmetoder; modifierade Newtonmetoder.; Optimization and Systems Theory; Optimeringslära och systemteori;

    Abstract : Methods for solving nonlinear optimization problems typically involve solving systems of equations. This thesis concerns approaches for accelerating some of those methods. In our setting, accelerating involves finding a trade-off between the computational cost of an iteration and the quality of the computed search direction. READ MORE

  4. 2. Control and Analysis of Pulse-Modulated Systems

    Author : Stefan Almér; Ulf Jönsson; Gilead Tadmor; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Pulse-width modulation; Periodic systems; Stability analysis; Harmonic analysis; Lyapunov methods; Dynamic phasors; Harmonic transfer function; Switched mode power converters; Sampled data modeling; H-infinity synthesis; Optimization; systems theory; Optimeringslära; systemteori;

    Abstract : The thesis consists of an introduction and four appended papers. In the introduction we give an overview of pulse-modulated systems and provide a few examples of such systems. Furthermore, we introduce the so-called dynamic phasor model which is used as a basis for analysis in two of the appended papers. READ MORE

  5. 3. Self-organization and Intervention of Nonlinear Multi-agent Systems

    Author : Yuecheng Yang; Xiaoming Hu; Torkel Glad; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; multi-agent system; linear system; nonlinear system; opinion dynamics; crowd dynamics; leader-follower based model; optimal control; Tillämpad matematik och beräkningsmatematik; Applied and Computational Mathematics;

    Abstract : This dissertation concerns the self-organization behaviors in different types of multi-agent systems, and possible ways to apply interventions on top ofthat to achieve certain goals. A bounded confidence opinion dynamics modelis considered for the first two papers. READ MORE

  6. 4. Preconditioners and fundamental solutions

    Author : Per Sundqvist; Henrik Brandén; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Numerical Analysis; Numerisk analys;

    Abstract : New preconditioning techniques for the iterative solution of systems of equations arising from discretizations of partial differential equations are considered. Fundamental solutions, both of differential and difference operators, are used as kernels in discrete, truncated convolution operators. READ MORE

  7. 5. Solution to boundary-contact problems of elasticity in mathematical models of the printing-plate contact system for flexographic printing

    Author : Nikolai Kotik; Yury Shestopalov; Stig Larsson; Karlstads universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; boundary-contact problem; elasticity; integral equation; approximate decomposition; Applied mathematics; Tillämpad matematik; Matematik; Mathematics;

    Abstract : Boundary-contact problems (BCPs) are studied within the frames ofclassical mathematical theory of elasticity and plasticityelaborated by Landau, Kupradze, Timoshenko, Goodier, Fichera andmany others on the basis of analysis of two- and three-dimensionalboundary value problems for linear partial differential equations.A great attention is traditionally paid both to theoreticalinvestigations using variational methods and boundary singularintegral equations (Muskhelishvili) and construction of solutionsin the form that admit efficient numerical evaluation (Kupradze). READ MORE