Advanced search

Showing result 1 - 5 of 29 swedish dissertations matching the above criteria.

  2. 1. Selected Topics in Homogenization

    Author : Jens Persson; Anders Holmbom; Liselott Flodén; Marianne Olsson Lindberg; Mårten Gulliksson; Peter Wall; Mittuniversitetet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; homogenization theory; H-convergence; two-scale convergence; very weak two-scale convergence; multiscale convergence; very weak multiscale convergence; evolution-multiscale convergence; very weak evolution-multiscale convergence; λ-scale convergence; non-periodic linear elliptic problems; evolution-multiscale linear parabolic problems; evolution-multiscale monotone parabolic problems; detection of scales of heterogeneity;

    Abstract : The main focus of the present thesis is on the homogenization of some selected elliptic and parabolic problems. More precisely, we homogenize: non-periodic linear elliptic problems in two dimensions exhibiting a homothetic scaling property; two types of evolution-multiscale linear parabolic problems, one having two spatial and two temporal microscopic scales where the latter ones are given in terms of a two-parameter family, and one having two spatial and three temporal microscopic scales that are fixed power functions; and, finally, evolution-multiscale monotone parabolic problems with one spatial and an arbitrary number of temporal microscopic scales that are not restricted to be given in terms of power functions. READ MORE

  4. 2. Sequential convergence for functions and operators

    Author : Jeanette Silfver; Mårten Gulliksson; Anders Holmbom; Nils Svanstedt; Mittuniversitetet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; homogenization; two-scale convergence; G-convergence; H-convergence; partial differential equations; functional analysis; heterogeneous media; MATHEMATICS; MATEMATIK;

    Abstract : The mathematical discipline homogenization theory is closely related to convergence issues. In this thesis different types of convergence are studied and put in relation to each other. We consider the classical concepts of G- and H-convergence and compensated compactness. READ MORE

  5. 3. Homogenization of Some Selected Elliptic and Parabolic Problems Employing Suitable Generalized Modes of Two-Scale Convergence

    Author : Jens Persson; Anders Holmbom; Liselott Flodén; Marianne Lindberg; Mårten Gulliksson; Peter Wall; Mittuniversitetet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; H-convergence; G-convergence; homogenization; multiscale analysis; two-scale convergence; multiscale convergence; elliptic partial differential equations; parabolic partial differential equations; monotone operators; heterogeneous media; non-periodic media; Mathematical analysis; Analys;

    Abstract : The present thesis is devoted to the homogenization of certain elliptic and parabolic partial differential equations by means of appropriate generalizations of the notion of two-scale convergence. Since homogenization is defined in terms of H-convergence, we desire to find the H-limits of sequences of periodic monotone parabolic operators with two spatial scales and an arbitrary number of temporal scales and the H-limits of sequences of two-dimensional possibly non-periodic linear elliptic operators by utilizing the theories for evolution-multiscale convergence and λ-scale convergence, respectively, which are generalizations of the classical two-scale convergence mode and custom-made to treat homogenization problems of the prescribed kinds. READ MORE

  6. 4. Distributed Optimization of P2P Media Delivery Overlays

    Author : Amir H. Payberah; Seif Haridi; Alberto Montresor; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; P2P overlay networks; P2P live streaming; Distributed optimization; Electronics; Elektronik; Computer and systems science; Data- och systemvetenskap;

    Abstract : Media streaming over the Internet is becoming increasingly popular. Currently, most media is delivered using global content-delivery networks, providing a scalable and robust client-server model. However, content delivery infrastructures are expensive. READ MORE

  7. 5. Distributed Optimization and Control : Primal--Dual, Online, and Event-Triggered Algorithms

    Author : Xinlei Yi; Karl H. Johansson; Dimos V. Dimarogonas; John S. Baras; Antonis Papachristodoulou; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Distributed nonconvex optimization; distributed online convex optimization; distributed event-triggered control; primal-dual algorithm; stochastic gradient descent; zeroth-order algorithm; Electrical Engineering; Elektro- och systemteknik;

    Abstract : In distributed optimization and control, each network node performs local computation based on its own information and information received from its neighbors through a communication network to achieve a global objective. Although many distributed optimization and control algorithms have been proposed, core theoretical problems with important practical relevance remain. READ MORE