Sökning: "beam quality"

Visar resultat 1 - 5 av 248 avhandlingar innehållade orden beam quality.

1. 1. Mixed Beam Dosimetry - From Reactor Core to BNCT Patient

   Författare :Per Munck af Rosenschöld; Lund Medicinsk strålningsfysik; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; BNCT; dosimetry; radiotherapy; mixed beam; quality assurance; in vivo dosimetry; Monte Carlo; ionization chamber; foil activation; MCNP; beam quality correction factor; photon transmission.; Nukleärmedicin; radiobiology; Nuclear medicine; radiobiologi; Radiofarmaceutisk teknik; Radiopharmaceutical technology;

   Sammanfattning : Accurate radiation dosimetry is of paramount importance in order to ensure safe delivery of radiotherapy, and for the possibility of meaningful evaluation of clinical trials, as the radiation absorbed dose is correlated to tissue response. The aim of the studies described in this thesis was to investigate and devise novel approaches to mixed beam dosimetry in boron neutron capture therapy (BNCT). LÄS MER

3. 2. Cone Beam Computed Tomography - radiation dose and image quality assessments

   Författare :Sara Lofthag-Hansen; Göteborgs universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Cone beam computed tomography; anatomic landmarks; dose-area product; image quality; implant planning; periapical diagnosis; radiation dosimetry;

   Sammanfattning : Diagnostic radiology has undergone profound changes in the last 30 years. New technologies are available to the dental field, cone beam computed tomography (CBCT) as one of the most important. LÄS MER

4. 3. Beam Diagnostics and Dynamics in Nonlinear Fields

   Författare :Jim Ögren; Roger Ruber; Volker Ziemann; Klaus Leifer; Stephen Peggs; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Beam diagnostics; Nonlinear beam dynamics; Accelerator physics;

   Sammanfattning : Particle accelerators are indispensable tools for probing matter at the smallest scales and the improvements of such tools depend on the progress and understanding of accelerator physics. The Compact Linear Collider (CLIC) is a proposed, linear electron–­positron collider on the TeV-scale, based at CERN. 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. On Quality in Radiotherapy Treatment Plan Optimisation

   Författare :Hunor Benedek; Lund Medicinsk strålningsfysik; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Pareto optimisation; Pareto fronts; Dose prediction; Machine learning; Deliverable treatment plans; Volumetric modulated arc therapy; IMRT; patient-specific plan quality; plan quality; Multi Criteria Optimisation; Automated Treatment Planning;

   Sammanfattning : Radiotherapy is one of the essential treatments used in the fight against cancer. The goal of radiotherapy is to deliver a high dose of ionising radiation to the tumour volume and at the same time minimise the effect on healthy tissue by reducing the radiation to critical organs. LÄS MER