Sökning: "standard of opacity"

Hittade 5 avhandlingar innehållade orden standard of opacity.

  1. 1. Sources of Dust Extinction in Type Ia Supernovae : Measurements and constraints from X-rays to the Infrared

    Författare :Joel Johansson; Edvard Mörtsell; Ariel Goobar; Rahman Amanullah; Bruno Leibundgut; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; supernovae; interstellar dust; circumstellar dust; cosmology; fysik; Physics;

    Sammanfattning : The use of Type Ia supernovae (SNe Ia) as distance indicators is essential for studying the expansion history of the Universe and for exploring the nature of dark energy. However, a lack of understanding of the progenitor systems and the empirically derived colour-brightness corrections represent severe limitations for SNe Ia as cosmological probes. LÄS MER

  3. 2. Efficient rendering of semi-transparent geometry in real-time

    Författare :Erik Sintorn; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Rendering images of semi-transparent geometry representing e.g. LÄS MER

  4. 3. Quantitative cataract measurement with the Scheimpflug technique

    Författare :Wen Qian; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :Scheimpflug photography; back scattered light; cataracts; human lens nuclear opacities; aqueous suspension of polystyrene spheres; standard of opacity;

    Sammanfattning : Cataract is the most prevalent blinding eye disease. Scheimpflug photography is an objective method for documentation of lens nuclear opacity. Using the Scheimpflug slit-lamp technique, a photograph, in focus from the anterior surface of the cornea to the posterior surface of the lens, can be obtained. LÄS MER

  5. 4. CT Colonography: implementation and technical developments

    Författare :Valeria A Fisichella; Göteborgs universitet; []
    Nyckelord :X-ray Computed Tomography; Computed Tomographic Colonography; Computer-Assisted Image Processing; Three-Dimensional Imaging; Colonoscopy; Colon; Rectum; Colorectal Neoplasms; Computer-Assisted Diagnosis; Ionizing Radiation;

    Sammanfattning : Background: Computed tomographic colonography (CTC) is a minimally invasive imaging method for the detection of colorectal neoplasms. Uncertainty about its diagnostic performance, optimal visualization method, long learning curve and radiation exposure are among problems with CTC, affecting its implementation in routine health care. LÄS MER

  7. 5. Language Based Covert Channel Avoidance

    Författare :Daniel Hedin; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Common protection mechanisms fail to provide end-to-end security; programs with legitimate access to secret information are not prevented from leaking this to the world by accident or malice. Protecting the access to information is not enough to solve this problem. We have to ensure that the program uses the information in a secure way. LÄS MER