Sökning: "Correction method"

Visar resultat 1 - 5 av 308 avhandlingar innehållade orden Correction method.

  1. 1. Characterization and Correction of Analog-to-Digital Converters

    Författare :Henrik Lundin; Peter Händel; Mikael Skoglund; Paolo Carbone; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; analog-to-digital converter; ADC; correction; post-correction; look-up table; characterization; calibration; Signal processing; Signalbehandling;

    Sammanfattning : Denna avhandling behandlar analog-digitalomvandling. I synnerhet behandlas postkorrektion av analog-digitalomvandlare (A/D-omvandlare). A/D-omvandlare är i praktiken behäftade med vissa fel som i sin tur ger upphov till distorsion i omvandlarens utsignal. LÄS MER

  3. 2. Colour Correction of Underwater Images Using Spectral Data

    Författare :Julia Åhlén; Ewert Bengtsson; Jussi Parkkinen; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Bildanalys; Colour; Correction; Attenuation; Coefficient; Underwater; Bildanalys; Image analysis; Bildanalys; Computer science;

    Sammanfattning : For marine sciences sometimes there is a need to perform underwater photography. Optical properties of light cause severe quality problems for underwater photography. Light of different energies is absorbed at highly different rates under water causing significant bluishness of the images. LÄS MER

  4. 3. Corrections for improved quantitative accuracy in SPECT and planar scintigraphic imaging

    Författare :Anne Larsson; Lennart Johansson; Katrine Åhlström Riklund; Bertil Axelsson; Umeå universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Quantitative SPECT; scintigraphic imaging; attenuation correction; scatter correction; collimator-detector response; septal penetration; background correction; Monte Carlo simulation; Radiological physics; Radiofysik;

    Sammanfattning : A quantitative evaluation of single photon emission computed tomography (SPECT) and planar scintigraphic imaging may be valuable for both diagnostic and therapeutic purposes. For an accurate quantification it is usually necessary to correct for attenuation and scatter and in some cases also for septal penetration. LÄS MER

  5. 4. Accuracy, efficiency and robustness for rigid particle simulations in Stokes flow

    Författare :Anna Broms; Anna-Karin Tornberg; Mattias Sandberg; Eric Keaveny; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Stokes flow; rigid particles; accuracy; fundamental solutions; method of images; multiblob; contact avoiding; complementarity problem; barrier method; elliptic PDE; grid optimisation; pair-correction; boundary integral equations; Stokesflöde; noggrannhet; stela partiklar; fundamentallösningar; randintegralekvation; reflektionspunkter; multiblob; kontaktundvikande algoritmer; komplementaritetsproblem; barriärmetod; elliptisk PDE; gridoptimering; parkorrektion; Numerical Analysis; Numerisk analys;

    Sammanfattning : The thesis concerns simulation techniques for systems of nano- to micro-scaled rigid particles immersed in a viscous fluid, ubiquitous in nature and industry. With negligible fluid inertia, the set of PDEs known as the Stokes equations can be used to model the hydrodynamics. LÄS MER

  7. 5. Advances in quantitative emission tomography : development and analysis of methods for validation and correction

    Författare :Cathrine Jonsson; Magnus Dahlbom; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; SPECT; Quantification; rCBF; Scatter correction; Phantoms; medicinsk strålningsfysik; Medical Radiation Physics;

    Sammanfattning : The nuclear medicine imaging techniques SPECT and PET are sensitive tools in mapping various physiological and biochemical processes in vivo. This work was devoted to investigations of methodological and physical properties of the SPECT technique as well as developing methods for validation and correction. LÄS MER