Sökning: "jacobian"

Visar resultat 1 - 5 av 33 avhandlingar innehållade ordet jacobian.

  1. 1. Parameter estimation in heterogeneous catalysis

    Författare :Jonas Sjöblom; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; microkinetic modelling; Jacobian; Parameter estimation; Latent Variable models; Design of experiments; heterogeneous catalysis; sensitivity analysis; Experimental design;

    Sammanfattning : The detailed modelling of heterogeneous catalytic systems is challenging due to the unknown nature of new catalytic materials as well as the often required transient nature of the resulting models. Thus, this thesis deals with the methodologies involved in the kinetic modelling of heterogeneous catalysis and in particular NOx reduction systems. LÄS MER

  2. 2. On efficient and adaptive modelling of friction damping in bladed disks

    Författare :Mohammad Afzal; Leif Kari; Ines Lopez Arteaga; Muzio M Gola; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; High cycle fatigue; Friction contact; Jacobian matrix; Shroud contact; Strip damper; Multiharmonic balance method; Contact stiffness; Cyclic symmetry; Nodal diameter; Magnetostrictive actuator; Magnetic field; Engineering Mechanics; Teknisk mekanik;

    Sammanfattning : This work focuses on efficient modelling and adaptive control of friction damping in bladed disks. To efficiently simulate the friction contact, a full-3D time-discrete contact model is reformulated and an analytical expression for the Jacobian matrix is derived that reduces the computation time drastically with respect to the classical finite difference method. LÄS MER

  3. 3. Fast Microwave Tomography Algorithm for Breast Cancer Imaging

    Författare :Samar Hosseinzadegan; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; breast cancer; computational cost; inverse problem; discrete dipole approximation; microwave tomography; forward solver; Jacobian matrix;

    Sammanfattning : Microwave tomography has shown promise for breast cancer imaging. The microwaves are harmless to body tissues, which makes microwave tomography a safe adjuvant screening to mammography. LÄS MER

  4. 4. A study of hydroelastic fluid-structure interaction with application to immersed cantilevers

    Författare :Johan Lorentzon; Strömningsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Partitioned Fluid-Structure; Blocked Gauss-Seidel; Jacobian-free Newton-Krylov methods; Incompressible fluid; Finite Strain; Total Lagrangian; Arbitrary Lagrange Euler method; Vector acceleration;

    Sammanfattning : This study presents an approach for partitioned fluid-structure interaction (FSI) applied to large structural deformations, where an incompressible turbulent solver is combined with a structural solver. The implementation is based upon two different open-source libraries by using MPI as a parallel communication protocol, the packages deal. LÄS MER

  5. 5. Efficient Solvers for Space-Time Discontinuous Galerkin Spectral Element Methods

    Författare :Lea Miko Versbach; Numerisk analys; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Discontinuous Galerkin Method; Spectral Element Method; Finite Volume Method; Implicit Schemes; Preconditioner; Multigrid Method; Space-Time; Lobatto IIIC Method; Local Fourier Analysis;

    Sammanfattning : In this thesis we study efficient solvers for space-time discontinuous Galerkin spectral element methods (DG-SEM). These discretizations result in fully implicit schemes of variable order in both spatial and temporal directions. LÄS MER