Sökning: "Attenuation coefficient"

Visar resultat 16 - 20 av 23 uppsatser innehållade orden Attenuation coefficient.

  1. 16. Performance Assessment of Cerenkov Emission Imaging

    Master-uppsats, Lunds universitet/Sjukhusfysikerutbildningen; Lunds universitet/Medicinsk strålningsfysik, Lund

    Författare :Emma Mellhammar; [2013]
    Nyckelord :Medicine and Health Sciences;

    Sammanfattning : Laddade partiklar med hög energi kan ibland färdas snabbare än ljusets hastighet i det medium det för stunden befinner sig i. När detta sker, emitteras så kallat Cerenkovljus. Ljuset ligger inom det synliga spektret och kan alltså detekteras med vanlig kamerateknik. LÄS MER

  3. 17. Three material decomposition in dual energy CT for brachytherapy using the iterative image reconstruction algorithm DIRA : Performance of the method for an anthropomorphic phantom

    Master-uppsats, Institutionen för medicinsk teknik; Tekniska högskolan

    Författare :Robin Westin; [2013]
    Nyckelord :DECT; Iterative reconstruction; Tissue decomposition; Numerical stability; Uncertainty propagation;

    Sammanfattning : Brachytherapy is radiation therapy performed by placing a radiation source near or inside a tumor. Difference between the current water-based brachytherapy dose formalism (TG-43) and new model based dose calculation algorithms (MBSCAs) can differ by more than a factor of 10 in the calculated doses. LÄS MER

  4. 18. Accuracy of inverse treatment planning on computed tomography like images derived from magnetic resonance data

    Master-uppsats, Institutionen för fysik

    Författare :Mohammad Mehdi Akhtari; [2013]
    Nyckelord :;

    Sammanfattning : Treatment planning for radiotherapy involves different types of imaging to delineate target volume precisely. The most suitable sources to get 3D information of the patient are the computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET)/CT modalities. LÄS MER

  5. 19. Fishing from space : mackerel fishing in Icelandic waters and correlation with satellite variables

    Master-uppsats, Lunds universitet/Institutionen för naturgeografi och ekosystemvetenskap

    Författare :Kristin Agustsdottir; [2013]
    Nyckelord :chlorophyll; downwelling diffuse attenuation coefficient; photosynthetically available radiation; water leaving radiance; physical geography and ecosystem analysis; sea surface temperature; Atlantic Mackerel; Scomber scombrus; Icelandic waters; satellite variables; remote sensing; Earth and Environmental Sciences;

    Sammanfattning : As concentrations of measured CO2 in the atmosphere reach a record high it is important to attempt all possible efforts to reduce the emissions of greenhouse gases (GHG) in all aspects of industry. The fishing sector contributes 15% of total GHG emission in Iceland, with the majority originating from fishing vessels using fossil fuel. LÄS MER

  7. 20. Integrated Optics Set-up for Photodynamic Therapy

    Master-uppsats, Lunds universitet/Atomfysik

    Författare :Cristina Pantaleone; [2012]
    Nyckelord :Photodynamic therapy; IPDT; light-matter interaction; optical circuit; prostate cancer; modulation frequency encoding; Technology and Engineering;

    Sammanfattning : Interstitial photodynamic therapy is a local solid cancer treatment technique that relies on the simultaneous presence of light, photosensitizer and oxygen. SpectraCure AB has been developing a light delivery system for prostate cancer therapy. LÄS MER