Search for dissertations about: "spectral decomposition"

Showing result 6 - 10 of 56 swedish dissertations containing the words spectral decomposition.

  2. 6. Spectral-element simulations of turbulent wall-bounded flows including transition and separation

    Author : Johan Malm; Dan Henningson; Philipp Schlatter; Suad Jakirlic; KTH; []
    Keywords : spectral-element method; direct numerical simulation DNS ; large-eddy simulation LES ; turbulence; transition; over-integration; three-dimensional separation; massively parallel simulations; proper orthogonal decomposition POD ; Koopman modes; vorticity stretching; coherence; SRA - E-vetenskap SeRC ; SRA - E-Science SeRC ;

    Abstract : The spectral-element method (SEM) is used to study wall-bounded turbulent flowsin moderately complex geometries. The first part of the thesis is devoted to simulations of canonical flow cases, such as temporal K-type transitionand turbulent channel flow, to investigate general resolution requirements and computational efficiency of the numerical code nek5000. READ MORE

  4. 7. Algorithms for analysis of NMR projections: Design, implementation and applications

    Author : Jonas Fredriksson; Göteborgs universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NMR; projection experiments; decomposition; algorithm; automatic;

    Abstract : With an increasing rate of protein expressions the need for fast protein characterization has become more important. Protein NMR has long been an important contributor for protein characterization; being one of a few techniques that can study proteins at atomic resolution in their native state. READ MORE

  5. 8. An experimental and numerical study of an automotive cooling module

    Author : Anders Rynell; Gunilla Efraimsson; Michael Shur; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fan installation effects; spectral decomposition; aeroacoustics; Vehicle and Maritime Engineering; Farkostteknik;

    Abstract : Heavy vehicles are major emitters of noise. Especially at idle or low vehicle speeds a large portion of the noise emanates from the fan that forces the flow through the cooling module. The aim of this work is to investigate and reveal aerodynamic and acoustic installation effects linked to the cooling package. READ MORE

  6. 9. 3D Time-lapse Analysis of Seismic Reflection Data to Characterize the Reservoir at the Ketzin CO2 Storage Pilot Site

    Author : Fei Huang; Christopher Juhlin; Alireza Malehmir; Ari Tryggvason; Andy Chadwick; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; CO2 storage; 3D Time-lapse 4D ; Reservoir characterization; Seismic simulation; Spectral decomposition; Wavelet phase; Tuning frequency; Thin-layer thickness; Seismic monitoring; Seismic processing; Quantitative interpretation; Geofysik med inriktning mot fasta jordens fysik; Geophysics with specialization in Solid Earth Physics;

    Abstract : 3D time-lapse seismics, also known as 4D seismics, have great potential for monitoring the migration of CO2 at underground storage sites. This thesis focuses on time-lapse analysis of 3D seismic reflection data acquired at the Ketzin CO2 geological storage site in order to improve understanding of the reservoir and how CO2 migrates within it. READ MORE

  7. 10. Characterization and Optimization of Silicon-strip Detectors for Mammography and Computed Tomography

    Author : Han Chen; Mats Danielsson; cheng xu; Andrew Maidment; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; mammography; anti-scatter grid; photon-counting; spectral computed tomography; silicon strip; ASIC; energy resolution; Compton scatter; material decomposition; K-edge imaging; Medical Technology; Medicinsk teknologi;

    Abstract : The goal in medical x-ray imaging is to obtain the image quality requiredfor a given detection task, while ensuring that the patient dose is kept as lowas reasonably achievable. The two most common strategies for dose reductionare: optimizing incident x-ray beams and utilizing energy informationof transmitted beams with new detector techniques (spectral imaging). READ MORE