Sökning: "scattering methods"

Visar resultat 1 - 5 av 380 avhandlingar innehållade orden scattering methods.

  1. 1. Time Domain Boundary Element Methods for Acoustic Scattering

    Författare :Georgios Natsiopoulos; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; time domain; curved surface; room acoustics; boss model; boundary element method; regularization; transient; Hermite interpolation; hypersingular; acoustic scattering; vector potential;

    Sammanfattning : In room acoustics, numerical computation of scattering phenomena is an important subject, since it is needed to accurately predict the influence of reflectors, the audience, balconies, etc, on the perceived acoustic quality of auditoria. The large physical volumes of auditoria and the wide frequency content of music and speech, together with the complicated geometries involved however, makes predictions in room acoustics a challenging task from a computational point of view. LÄS MER

  3. 2. High frequency scattering and spectral methods

    Författare :Imad Akeab; Sven-Erik Sandström; Andreas Asheim; Linnéuniversitetet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Waves; Signals and Systems; Vågor; signaler och system;

    Sammanfattning : This thesis consists of five parts. The first part is an introduction with references to some recent work on 2D electromagnetic scattering problems at high frequencies. It also presents the basic integral equation types for impenetrable objects and the standard elements of the method of moments. LÄS MER

  4. 3. Light propagation in an anisotropically scattering medium

    Författare :Elena Vasileva; Sergei Popov; Miguel A. Alonso; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; anisotropic light scattering; scattering material characterization; polarization dependent scattering; diffusive media; hierarchical structure; biocomposites; wood modification; transparent wood; microfibrils angle; organic materials; polymer active devices; dye lasers; coherence; polarization; degree of polarization.; Fysik; Physics;

    Sammanfattning : Scattering is the main phenomenon of light-matter interaction. In this thesis, we consider one specific case of light propagation in a material whose structure causes anisotropic optical scattering - transparent wood. LÄS MER

  5. 4. Radiation and Scattering from Conformal Array Antennas

    Författare :Björn Thors; KTH; []
    Nyckelord :conformal antennas; antenna arrays; antenna radiation patterns; radar cross sections; electromagnetic scattering; UTD; moment methods; high frequency method; hybrid method; mutual coupling;

    Sammanfattning : This thesis deals with radiation and scattering fromconformal array antennas. A hybrid technique between the Methodof Moments (MoM) and different asymptotic methods is used forthe analysis, combining the accuracy of the MoM and theefficiency of the asymptotic methods. LÄS MER

  7. 5. Intraocular light scattering and glare testing

    Författare :Jörgen Thaung; Göteborgs universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; light scattering; light scattering factor; glare; veling luminance; contrast sensitivity; adaptation; psychophysics; light transmission; integrating sphere; human lens; cataract; aging.;

    Sammanfattning : Aims: To analyze the parameters that are used in psychophysical glare testing and the validity of the light scattering factor (LSF). The purpose is also to investigate the light scattering properties in excised eye lenses, and to compare these properties with light transmission for different wavelengths in aging and cataractous lenses. LÄS MER