Sökning: "dose measurements"

Visar resultat 1 - 5 av 231 avhandlingar innehållade orden dose measurements.

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

   Författare :Bengt Hemdal; Malmö Medicinsk strålningsfysik; []
   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

3. 2. Studies on the Gamma Radiation Environment in Sweden with Special Reference to 137Cs

   Författare :Sara Almgren; Göteborgs universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; gamma radiation; caesium; 137Cs; deposition; migration; precipitation; in situ; CDE; NWF; Chernobyl; soil sampling; field measurements; dose measurements; dose rate; TLD; natural radiation; Kriging;

   Sammanfattning : Gamma radiation in the environment today mainly originates from naturally occurring radionuclides, but anthropogenic radionuclides, such as 137Cs, contribute in some areas. In order to assess population exposure in case of fallout from nuclear weapons (NWF) or accidents, knowledge and monitoring of external gamma radiation and radionuclide concentrations in the environment is important. LÄS MER

4. 3. Orthopaedic measurements with computed radiography. Methodological development, accuracy, and radiation dose with special reference to the weight-bearing lower extremity and the dislocating patella

   Författare :Jan Sanfridsson; Lund Ortopedi; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Clinical physics; digital.; computer-assisted; Picture Archiving and Communication Systems; computed radiography; radiography; effective dose; radiation dosage; measurements; biomechanics; dislocating patella; musculoskeletal; patellofemoral joint; Knee joint; radiology; tomography; medical instrumentation; Klinisk fysiologi; radiologi; tomografi; medicinsk instrumentering;

   Sammanfattning : The overall aim of this study was to develop and evaluate a measurement system for computed radiography (CR) and Picture Archiving and Communication Systems (PACS), permitting measurements of long distances and angles in and between related images. The developed measurement system, which was based on the QUESTOR Precision Radiography (QPR) system, was applied to the weight-bearing knee with special reference to the dislocating patella. LÄS MER

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

   Författare :Stefan Johnsson; Lund Medicinsk strålningsfysik; []
   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

7. 5. From Particle-Production Cross Sections to KERMA and Absorbed Dose for the Case 96 MeV n-12C Interactions

   Författare :Bel E. Bergenwall; Ayşe Ataç; Eva Lund; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nuclear physics; Fast neutrons; En = 96 MeV; charged-particle production; 12C n; px ; 12C n; dx ; 12C n; tx ; 12C n; 3Hex ; 12C n; ax reactions; cross sections; KERMA; microscopic measurements; absorbed dose; Kärnfysik; Nuclear physics; Kärnfysik;

   Sammanfattning : Neutron-carbon interactions have been studied with a focus on charged-particle production of relevance to radiation protection and medical applications, such as cancer therapy. The measurements have been performed using the particle-detection setup, MEDLEY, and the 96 MeV neutron beam at the The Svedberg Laboratory in Uppsala. LÄS MER