Sökning: "Bildrekonstruktion"

Visar resultat 1 - 5 av 14 uppsatser innehållade ordet Bildrekonstruktion.

  1. 1. Deep Learning-based Regularizers for Cone Beam Computed Tomography Reconstruction

    Master-uppsats, KTH/Matematisk statistik

    Författare :Sabina Syed; Josefin Stenberg; [2023]
    Nyckelord :Adversarial Convex Regularization; Computer Vision; Cone Beam Computed Tomography; Convolutional Neural Networks; Deep Learning; Image Reconstruction; Adversarial Convex Regularization; Bildrekonstruktion; Datorseende; Djupinlärning; Faltningsnätverk; Volymtomografi;

    Sammanfattning : Cone Beam Computed Tomography is a technology to visualize the 3D interior anatomy of a patient. It is important for image-guided radiation therapy in cancer treatment. During a scan, iterative methods are often used for the image reconstruction step. LÄS MER

  3. 2. Evaluation of a Novel Reconstruction Framework for Gamma Knife Cone-Beam CT - The Impact of Scatter Correction and Noise Filtering on Image Quality and Co-registration Accuracy

    Master-uppsats, KTH/Fysik

    Författare :Ida Hägnestrand; [2023]
    Nyckelord :Gamma Knife; Cone-beam computed tomography; Image quality; Image reconstruction; Co-registration; Contrast; Uniformity; Spatial resolution; Scatter correction; Wiener filter; Noise filter; Patient positioning; Stereotactic radiosurgery; Gammakniv; Strålkniv; Cone-Beam Computed Tomography; Bildkvalitet; Bildrekonstruktion; Co-registrering; Kontrast; Uniformitet; Spatial upplösning; Spridningskorrigering; Wienerfilter; Brusfilter; Stereotaktisk strålkirurgi;

    Sammanfattning : The Gamma Knife is a non-invasive stereotactic radiosurgery system used for treatments of deep targets in the brain. Accurate patient positioning is needed for precise radiation delivery to the target. LÄS MER

  4. 3. Respiratory Motion Correction in PET Imaging: Comparative Analysis of External Device and Data-driven Gating Approaches

    Master-uppsats, KTH/Fysik

    Författare :Nina Lindström Söraas; [2023]
    Nyckelord :PET CT; Tomographic reconstruction; Respiratory gating techniques; Image registration; Motion correction; PET CT; Tomografisk rekonstruktion; Gating tekniker; Bildregistrering; Rörelsekorrigering;

    Sammanfattning : Positron Emission Tomography (PET) is pivotal in medical imaging but is prone to artifactsfrom physiological movements, notably respiration. These motion artifacts both degradeimage quality and compromise precise attenuation correction. LÄS MER

  5. 4. Djupinlärning på sinogram för bildrekonstruktion från spektral CT

    Kandidat-uppsats, KTH/Skolan för teknikvetenskap (SCI)

    Författare :Adam Ågren; Dennis Åkerström; [2021]
    Nyckelord :;

    Sammanfattning : I takt med den nya utvecklingen av fotonräknande datortomografi med möjligheter till lägre stråldoser kommer även krav på bättre metoder för brusreducering och bildrekonstruktion. För att lösa detta problem föreslås appliceringen av ett neuralt nätverk för att filtrera bort brus och rekonstruera bilderna. LÄS MER

  7. 5. Real versus Simulated data for Image Reconstruction : A comparison between training with sparse simulated data and sparse real data

    Kandidat-uppsats, KTH/Skolan för elektroteknik och datavetenskap (EECS)

    Författare :Aïssata Maiga; Johanna Löv; [2021]
    Nyckelord :Event based camera; image reconstruction; simulated data; real data; FireNet; E2VID; Event based camera; image reconstruction; simulated data; real data; FireNet; E2VID;

    Sammanfattning : Our study investigates how training with sparse simulated data versus sparse real data affects image reconstruction. We compared on several criteria such as number of events, speed and high dynamic range, HDR. The results indicate that the difference between simulated data and real data is not large. LÄS MER