Essays about: "preconditioning"

Showing result 1 - 5 of 6 essays containing the word preconditioning.

  1. 1. Performance comparisons of preconditioned iterative methods for problems arising in PDE-constrained optimization

    University essay from Uppsala universitet/Institutionen för informationsteknologi

    Author : Shiraz Farouq; [2015]
    Keywords : ;

    Abstract : The governing dynamics of simple and complex processes, whether physical, biological, social, economic, engineering, or even rather a mere figment of imagination, can be studied via numerical simulations of mathematical models. These models in many cases can be thought to consist of one, or frequently, several coupled partial differential equations (PDEs). READ MORE

  2. 2. Inversion of 2D Magnetotelluric and Radiomagnetotelluric data with Non-Linear Conjugate Gradient techniques

    University essay from Uppsala universitet/Geofysik

    Author : Dominik Zbinden; [2015]
    Keywords : Numerical solutions; inverse theory; non-linear conjugate gradients; preconditioning; electromagnetic theory; magnetotellurics;

    Abstract : I implemented and tested the method of Non-Linear Conjugate Gradients (NLCG) to invert magnetotelluric (MT) and radiomagnetotelluric (RMT) data in two dimensions. The forward problem and the objective function gradients were computed using finite-difference methods. READ MORE

  3. 3. Parallel graph coloring : Parallel graph coloring on multi-core CPUs

    University essay from Uppsala universitet/Avdelningen för beräkningsvetenskap

    Author : Per Normann; [2014]
    Keywords : Parallel graph coloring multi coloring;

    Abstract : In recent times an evident trend in hardware is to opt for multi-core CPUs. This has lead to a situation where an increasing number of sequential algorithms are parallelized to fit these new multi-core environments. The greedy Multi-Coloring algorithm is a strictly sequential algorithm that is used in a wide range of applications. READ MORE

  4. 4. Prototype Development of an A-Mode Ultrasound Based Intrafraction Motion Management System

    University essay from KTH/Skolan för teknik och hälsa (STH); KTH/Skolan för teknik och hälsa (STH)

    Author : Abebe Hailu; Fredrik Lundqvist; [2013]
    Keywords : Intrafraction motion management; A-mode ultrasound; stereotactic body radiation therapy; ultrasonic distance measurement; embedded system;

    Abstract : Owing to the steep dose fall-off curves of high precision and accuracy radiation therapy (RT) modalities such as stereotactic body RT (SBRT), treatment plans with extraordinarily small margins to organs at risk (OARs), such as the spinal cord, has been made possible. With this development, patient movements during treatment, i.e. READ MORE

  5. 5. Boundary Summation Equation Preconditioning for Ordinary Differential Equations with Constant Coefficients on Locally Refined Meshes

    University essay from Linköpings universitet/Linköpings universitet/Matematiska institutionenTekniska högskolan

    Author : Maimaitiyiming Guzainuer; [2012]
    Keywords : Ordinary differential equations; constant coefficients; finite difference; boundary summation equation; GMRES; convergence rate.;

    Abstract : This thesis deals with the numerical solution of ordinary differential equations (ODEs) using finite difference (FD) methods. In particular, boundary summation equation (BSE) preconditioning for FD approximations for ODEs with constant coefficients on locally refined meshes is studied. READ MORE