Sökning: "radiation quality"

Visar resultat 1 - 5 av 270 avhandlingar innehållade orden radiation quality.

  1. 1. The microdosimetric variance-covariance method used for beam quality characterization in radiation protection and radiation therapy

    Detta är en avhandling från Stockholm : Medicinsk strålningsfysik (tills m KI)

    Författare :Jan Erik Lillhök; Stockholms universitet.; [2007]
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; ionizing radiation; radiation quality; radiation protection; radiation therapy; microdosimetry; nanodosimetry; variance-covariance method; MEDICINE Physiology and pharmacology Radiological research Radiological physics; MEDICIN Fysiologi och farmakologi Radiologisk forskning Radiofysik; medicinsk strålningsfysik; Medical Radiation Physics;

    Sammanfattning : Radiation quality is described by the RBE (relative biological effectiveness) that varies with the ionizing ability of the radiation. Microdosimetric quantities describe distributions of energy imparted to small volumes and can be related to RBE. LÄS MER

  2. 2. Optical Studies For Synchrotron Radiation Beamlines

    Detta är en avhandling från MAX IV Laboratory, Lund University

    Författare :Walan Grizolli; Lund University.; Lunds universitet.; Lund University.; Lunds universitet.; [2015]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Synchrotron Radiation; Optics; X-ray Optics; Beamline; Polarimetry; Coherence; Storage Rings; Diffraction Limited Storage Rings;

    Sammanfattning : Synchrotron radiation sources have greatly contributed to the progress in many fields of science. The development of the storage ring technologies has made possible to obtain very low emittance electron beams, which together with the use of undulators allow guiding a very high photon flux into a very small spot required by the experiments. LÄS MER

  3. 3. Development and evaluation of an independent system for absorbed dose calculations in radiotherapy

    Detta är en avhandling från Stefan Johnsson (request by e-mail)

    Författare :Stefan Johnsson; Lund University.; Lunds universitet.; [2003]
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; medicinsk instrumentering; tomografi; radiologi; Klinisk fysiologi; tomography; medical instrumentation; radiology; Clinical physics; cancer; Cytologi; onkologi; cancerology; oncology; Cytology; PDA; mini-phantom; in-air equivalence; primary kerma; transmission measurement; stopping power ratio; entrance dose; beam quality; quality control; error prevention; monitor unit calculation; radiation therapy; dose calculation;

    Sammanfattning : The aim of this work was to develop, implement and evaluate an independent system with which to calculate the absorbed dose, delivered by high-energy X-ray beams, to the prescription point and the depth of dose maximum. The introduction of such a system in the clinical routine may help ensure high-quality treatment and avoidance of errors which may jeopardise the clinical outcome of the treatment (i. LÄS MER

  4. 4. Secondary absorbed dose distributions and radiation quality in light ion therapy

    Detta är en avhandling från Stockholm : Department of Physics, Stockholm University

    Författare :Martha Hultqvist; Stockholms universitet.; [2011]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; secondary doses; light ion therapy; radiation quality; Monte Carlo simulation; medicinsk strålningsfysik; Medical Radiation Physics;

    Sammanfattning : Radiotherapy with light ions offers the possibility of achieving a dose distribution which is highly conformed to the target volume while sparing normal tissues. For ions heavier than protons, an additional advantage is the increased Relative Biological Effectiveness (RBE) as compared to conventional photon and electron beams. LÄS MER

  5. 5. Evaluation of absorbed dose and image quality in mammography

    Detta är en avhandling från Stockholm : Department of Physics, Stockholm University

    Författare :Bengt Hemdal; Lund University.; Lunds universitet.; [2009]
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; optically stimulated luminescence; radioluminescence; in vivo dosimetry; dose reduction; dose protocol; average glandular dose; absorbed dose; Breast cancer; mammography; Monte Carlo; image quality; image quality criteria; contrast-detail phantom;

    Sammanfattning : Mammography refers to the X-ray examination of the human breast, and is considered the single most important diagnostic tool in the early detection of breast cancer, which is by far the most common cancer among women. There is good evidence from clinical trials, that mammographic screening can reduce the breast cancer mortality with about 30%. LÄS MER