Sökning: "preconditioning"

Visar resultat 16 - 20 av 71 avhandlingar innehållade ordet preconditioning.

  1. 16. Implementation of the spectral element method and iterative solution techniques for 3D controlled-source electromagnetic modelling

    Författare :Michael Weiss; Thomas Kalscheuer; Michael Becken; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Controlled source electromagnetis; Electromagnetic theory; Numerical modelling; Applied geophysics; Geo-Electromagnetics; Spectral element method; Iterative solution methods; Preconditioning;

    Sammanfattning : Controlled-source electromagnetic methods are imaging techniques applied at/on the surface of the Earth which record the electromagnetic field in order to assess the electrical conductivity distribution of the Earth’s subsurface, along with anomalies in this material property, as well as to characterise and interpret structures in Earth’s crust. Extracting information from the recorded electromagnetic data requires inverse modelling algorithms. LÄS MER

  3. 17. Remote Ischemic Preconditioning and its Effects on the Respiratory System

    Författare :Astrid Bergmann; Anders Larsson; Göran Hedenstierna; Thomas Hachenberg; Ola Winsö; Uppsala universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; one-lung ventilation; ventilation-induced lung injury; alveolar immune response; remote ischemic preconditioning; exhaled nitric oxide; animal model; Anestesiologi och intensivvård; Anaesthesiology and Intensive Care;

    Sammanfattning : Mechanical ventilation in itself can lead to pulmonary damage, and one-lung ventilation (OLV), necessary for thoracic surgery, accentuates this injury. Remote ischemic preconditioning (RIP) is a potential tool to reduce lung injury after mechanical ventilation, including OLV.  However, current data on pulmonary RIP-effects are contradictory. LÄS MER

  4. 18. Semi-Toeplitz preconditioning for linearized boundary layer problems

    Författare :Samuel Sundberg; Lina von Sydow; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Numerical Analysis; Numerisk analys;

    Sammanfattning : We have defined and analyzed a semi-Toeplitz preconditioner for time-dependent and steady-state convection-diffusion problems. Analytic expressions for the eigenvalues of the preconditioned systems are obtained. LÄS MER

  5. 19. Myocardial protection with special reference to ischemic preconditioning : an experimental study in the pig using a microdialysis technique

    Författare :Bernt Gerhard Wikström; Uppsala universitet; []
    Nyckelord :MEDICINE; MEDICIN;

    Sammanfattning : .... LÄS MER

  7. 20. On Numerical Solution Methods for Block-Structured Discrete Systems

    Författare :Petia Boyanova; Maya Neytcheva; Oleg Iliev; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Preconditioning techniques; Finite element method; Two-by-two block matrices; Optimal order methods; AMLI method; Cahn-Hilliard equation; Multiphase flow; Inexact Newton method; Beräkningsvetenskap med inriktning mot numerisk analys; Scientific Computing with specialization in Numerical Analysis;

    Sammanfattning : The development, analysis, and implementation of efficient methods to solve algebraic systems of equations are main research directions in the field of numerical simulation and are the focus of this thesis. Due to their lesser demands for computer resources, iterative solution methods are the choice to make, when very large scale simulations have to be performed. LÄS MER