Indications and practical application of strategies in the endovascular management of intracranial aneurysms

The occlusion of intracranial aneurysms is more successful and stable by properly planning the approach and application of endovascular techniques. The next step is a relentless analysis of the different indications of endovascular treatment, tailoring a strategy suitable for the specific case, and making more rational choices for the management of aneurysms. Indications and strategies according to the analysis of the aneurysmal complex are given, as well as pros and cons of the endovascular technique according to different anatomical locations.       &nbsp

Beam screen cryogenic control improvements for the LHC run 2

This paper presents the improvements made on the cryogenic control system for the LHC beam screens. The regulation objective is to maintain an acceptable temperature range around 20 K which simultaneously ensures a good LHC beam vacuum and limits cryogenic heat loads. In total, through the 27 km of the LHC machine, there are 485 regulation loops affected by beam disturbances. Due to the increase of the LHC performance during Run 2, standard PID controllers cannot keeps the temperature transients of the beam screens within desired limits. Several alternative control techniques have been studied and validated using dynamic simulation and then deployed on the LHC cryogenic control system in 2015. The main contribution is the addition of a feed-forward control in order to compensate the beam effects on the beam screen temperature based on the main beam parameters of the machine in real time