Search for dissertations about: "perturbation"

Showing result 21 - 25 of 434 swedish dissertations containing the word perturbation.

  1. 21. Nonlinearly Perturbed Renewal Equations : asymptotic Results and Applications

    Author : Ying Ni; Dmitrii Silvestrov; Anatoliy Malyarenko; Mats Gyllenberg; Mälardalens högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Nonlinearly perturbed renewal equation; perturbed renewal equation; nonlinear perturbation; non-polynomial perturbation; perturbed risk process; perturbed storage process; Mathematical statistics; Matematisk statistik; Mathematics Applied Mathematics; matematik tillämpad matematik;

    Abstract : In this thesis we investigate a model of nonlinearly perturbed continuous-time renewal equation. Some characteristics of the renewal equation are assumed to have non-polynomial perturbations, more specifically they can be expanded with respect to a non-polynomial asymptotic scale. READ MORE

  2. 22. Time-Dependent Many-Body Perturbation Theory: Possibilities and Limitations

    Author : Marc Puig von Friesen; Matematisk fysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Many-body perturbation theory; Correlation functions; Hubbard model; Non-equilibrium Green s functions; Fysicumarkivet A:2011:Puig von Friesen;

    Abstract : This dissertation investigates the possibilities and limitations of time-dependent many-body perturbation theory by studying small Hubbard clusters for which the exact solution is available. The first part of the thesis is comprised of a short introduction to the concepts and methodologies used. READ MORE

  3. 23. Pion and Kaon Dynamics at Higher Orders in Chiral Perturbation Theory

    Author : Pierre Dhonte; Teoretisk partikelfysik - Geonomgår omorganisation; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Matematisk och allmän teoretisk fysik; thermodynamics; statistical physics; gravitation; chiral perturbation theory; strong interactions; pseudo-scalar mesons; Mathematical and general theoretical physics; form factors; scattering; classical mechanics; relativity; quantum mechanics; klassisk mekanik; kvantmekanik; relativitet; statistisk fysik; termodynamik; Fysicumarkivet A:2004:Dhonte;

    Abstract : Higher orders calculations of processes involving the pion and kaon pseudo-scalar mesons are presented in the framework of three flavour Chiral Perturbation Theory. The purpose is two-fold. First determining the low energy constants of ChPT that are necessary for higher accuracy predictions. READ MORE

  4. 24. QM/MM free-energy perturbation and other methods to estimate ligand-binding affinities

    Author : Martin Olsson; Beräkningskemi; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Computer-aided drug design; protein–ligand binding; molecular dynamics; free-energy perturbation; QM MM; convergence;

    Abstract : Experimental drug discovery is very time-consuming, risky and comes at a huge cost, typically several billion USD per drug. Even though decades of experimental drug discovery have provided cures of many diseases, there are still diseases for which there is no effective drug available. READ MORE

  5. 25. Multi-Meson Dynamics in Chiral Perturbation Theory

    Author : Mattias Sjö; Partikel- och kärnfysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Spridningsamplituder; Effektiv Fältteori; Spontant symmetribrott; Ickelinjära sigmamodellen; Kirala Lagrangianer; Hadronspektroskopi; Strukturer och Interaktioner; Gitter-QCD; Scattering amplitudes; Effective Field Theories; Spontaneous Symmetry Breaking; Nonlinear sigma model; Chiral Lagrangians; Hadronic Spectroscopy; Structure and Interactions; Lattice QCD;

    Abstract : This thesis concerns scattering of light mesons in the case where the number of external particles exceeds four (that is, three or more particles in the initial or final state), calculated using chiral perturbation theory.This is both of theoretical interest in the study of scattering amplitudes, and relevant for systems of three or more pions simulated using lattice quantum chromodynamics. READ MORE