Sökning: "Fast Fourier Transform FFT"

Visar resultat 1 - 5 av 17 avhandlingar innehållade orden Fast Fourier Transform FFT.

  1. 1. Algorithms for Molecular Dynamics Simulations

    Författare :Fredrik Hedman; Aatto Laaksonen; Tom Darden; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; molecular dynamics; MD; first principles molecular dynamics; quantum mechanics; liquid water; parallel algorithm; data parallel; MPI; Coulombic interaction; Ewald summation; nonuniform fast Fourier transform; FFT; FFTW; NFFT; ENUF; Physical chemistry; Fysikalisk kemi;

    Sammanfattning : Methods for performing large-scale parallel Molecular Dynamics(MD) simulations are investigated. A perspective on the field of parallel MD simulations is given. Hardware and software aspects are characterized and the interplay between the two is briefly discussed. LÄS MER

  2. 2. Optimization of Rotations in FFTs

    Författare :Fahad Qureshi; Oscar Gustafsson; Mario Garrido; Jarmo Takala; Linköpings universitet; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Discrete Fourier transform; Fast Fourier transform; twiddle factor multiplication;

    Sammanfattning : The aims of this thesis are to reduce the complexity and increasethe accuracy of rotations carried out inthe fast Fourier transform (FFT) at algorithmic and arithmetic level.In FFT algorithms, rotations appear after every hardware stage, which are alsoreferred to as twiddle factor multiplications. LÄS MER

  3. 3. 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; NATURVETENSKAP; NATURVETENSKAP; TEKNIK OCH TEKNOLOGIER; NATURAL SCIENCES; NATURAL SCIENCES; ENGINEERING AND TECHNOLOGY; 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

  4. 4. Chemometric and signal processing methods for real time monitoring and modeling : applications in the pulp and paper industry

    Författare :Anders Björk; Lars-Göran Danielsson; Guy Dumont; KTH; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Acoustic; Vibration; Multivariate; Chemometrics; PLS; OSC; PCA; FFT; Wavelets; WT-MRS; CWT-FLE; Pulp Quality; CSF; Brightness; Tensile Strength properties; Optical Properties; Measurement Technology; On-line; Non-invasive; Process Control; Process Analysis; Process Analytical Technology; PAT.; Akustik; Vibrationer; Multivariat; Kemometri; PLS; OSC; PCA; FFT; Wavelets; WT-MRS; CWT-FLE; Massakvalitet; CSF; Ljushet; Dragstyrkeegenskaper; Optiska egenskaper; Mätteknik; On-line; Icke berörande mätning; Processtyrning; Processanalys; Processanalytisk Teknologi; PAT.; Analytical chemistry; Analytisk kemi;

    Sammanfattning : In the production of paper, the quality of the pulp is an important factor both for the productivity and for the final quality. Reliable real-time measurements of pulp quality are therefore needed. LÄS MER

  5. 5. Fish Lenses : Anatomy and Optics

    Författare :Tomasz M Kozłowski; Funktionell zoologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Plasticity; Development; Cellular structure; Lens fiber cells; Modeling; Laser Scanning; Schlieren photography; Fast Fourier Transform FFT ;

    Sammanfattning : I have investigated some of the biological regulatory mechanisms governing the development of crystalline lenses. I used fish as model animals because they possess optically interesting lenses, while the geometrical simplicity of fish lenses allows for studies that are difficult or impossible with the lenses of other animals. LÄS MER