For proton spot scanning, use of a real-time-image gating technique incorporating an implanted marker and dual fluoroscopy facilitates mitigation of the dose distribution deterioration caused by interplay effects. This study explored the advantages of using a real-time-image gating technique, with a focus on prostate cancer. Two patient-positioning methods using fiducial markers were compared: ...

This article presents an overview of a secure multicast framework as well as a secure multicast system demonstrator used for end-to-end performance assessment of secure multicast service delivery over satellite. The security framework relies on IP security with multicast extensions and Group Domain of Interpretation (GDOI) multicast key management. The framework addresses challenges in the deli...

The Agility multileaf collimator (Elekta AB, Stockholm, Sweden) has 160 leaves of projected width 0.5 cm at the isocenter, with maximum leaf speed 3.5 cms-1. These characteristics promise to facilitate fast and accurate delivery of radiotherapy, particularly volumetric-modulated arc therapy (VMAT). The aim of this study is therefore to create a beam model for the Pinnacle3 treatment planning sy...

Introduction Ion therapy allows a high precision, tumor conformal dose application but it is very sensitive to density changes along the beam path. Intra-fractional tumor motion due to respiration increases the risk of an incorrect irradiation and thus requires a reliable dosimetry as it was done by means of 3D in-beam PET for more than 400 patients at the experimental heavy ion treatment facil...

This paper addresses transmission impairment mechanisms in multiple-beam satellite communications systems that use active phased arrays. The communications link and system aspects are assessed through measurements and analysis. Three link parameters that contribute to transmission impairment are investigated and their effects on the overall carrier-to-interference ratio are quantified. First ar...

With a multi-stage collimation system and magnetic iron spoilers in the tunnel, the background particle fluxes on the ILC detector can be substantially reduced. At the same time, beam-halo interactions with collimators and protective masks in the beam delivery system create fluxes of muons and other secondary particles which can still exceed the tolerable levels for some of the ILC sub-detector...

Treatment verification has been a weak link in external beam radiation therapy. As new and more complicated treatment techniques, such as intensity-modulated radiation therapy (IMRT), are implemented into clinical practice, verifying the accuracy of treatment delivery becomes increasingly important. Existing methods for treatment verification are highly labor intensive. We have developed a meth...