Sökning: "Unequally spaced FFT"

Hittade 2 avhandlingar innehållade orden Unequally spaced FFT.

  1. 1. Inverse Problems in Tomography and Fast Methods for Singular Convolutions

    Författare :Fredrik Andersson; Matematik LTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Mathematics; Matematik; Unequally spaced FFT; Integral transforms; Singular integrals; Lippmann?Schwinger equation; Helmholtz equation; Inverse problems; Fast Gauss transform; Fast summation; Convolution; Radon transform; Tomography;

    Sammanfattning : There are two, partially interlaced, themes treated in this thesis; inverse problems of tomographic type and fast and accurate methods for the application of convolution operators. Regarding the first theme, the inverse problem of Doppler tomography is considered and the Doppler moment transform is introduced for that purpose. LÄS MER

  2. 2. Fast Radon Transforms and Reconstruction Techniques in Seismology

    Författare :Viktor Nikitin; Matematik LTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Fourier transform FFT ; Radon transforms; GPU;

    Sammanfattning : The measurements conducted in tomography and seismology typically yield large multidimensional data sets. This in combination with the fact that the data may have an irregular structure makes it computationally prohibitive to use simple reconstruction methods directly. LÄS MER