The assumption of cylindrical symmetry in radiotherapy accelerator models can pose a challenge for precise Monte Carlo modeling. This assumption makes it difficult to account for measured asymmetries in clinical dose distributions. We have performed a sensitivity study examining the effect of varying symmetric and asymmetric beam and geometric parameters of a Monte Carlo model for a Siemens PRI...

In this study, a PID controller was designed for the active vibration suppression of a smart beam equipped with PZT (Lead-Zirconate-Titanate) patches. The smart beam is a cantilever aluminium beam having eight symmetrically located surface-bonded piezoelectric patches. In this particular application, a group of PZT patches closed to the root of the beam was used as actuators and from the remain...

In this paper, static response and buckling analysis of functionally graded saturated porous beam resting on Winkler elastic foundation is investigated. The beam is modeled using higher-order shear deformation theory in conjunction with Biot constitutive law which has not been surveyed so far. Three different patterns are considered for porosity distribution along the thickness of the beam: 1) ...

The study of vibration response of a turbine blade helps to detect the crack presence in the blade which alters its dynamic characteristics. The change is characterized by changes in the modal parameters associated with natural frequencies. In this paper, study of vibration response is made for turbine blade in the presence of a crack like defect. Turbine blade is initially assumed as a cantile...

The Beam Transfer Function (BTF) belongs to the most powerful beam diagnostics methods, providing direct measurements of beam stability properties, impedances and various beam and lattice parameters. Here, we report about the first measurement of the transverse BTF and the corresponding stability diagrams in SIS 18. By comparing experimental BTF and stability diagrams with theoretical expressio...

The physical nature of beamstrahlung during beam-beam interaction in linear colliders is reviewed. We first make the distinction between a dense beam and a dilute beam. We then review the characteristics of synchrotron radiation (SR) and bremsstrahlung, and argue that for a wide range of beam parameters beamstrahlung is SR in nature, even if the beam is dilute. Some issues concerning the specif...

Realistic calculation of NLC luminosity has been performed using particle tracking in DI-MAD and beam-beam simulations in GUINEA-PIG code for various values of beam emit-tance, energy and beta functions at the Interaction Point (IP). Results of the simulations are compared with analytic luminosity calculations. The optimum range of IP beta functions for high luminosity was identified. Abstract ...

Additive Layer Manufacturing (ALM) methods, like Electron Beam Sintering (EBS) constitute an interesting process concerning the production of small series and customised products. However, transient effects occur during processing due to the different physical principles of an electron beam (EB). Thus, process knowledge from similar ALM technologies, for instance Selective Laser Melting, can no...

In recent years, a number of laser based H beam diagnostics systems have been developed in the Spallation Neutron Source (SNS). This talk reviews three types of laser based diagnostics at SNS: the laser wire profile monitors at superconducting linac (SCL), the laser transverse emittance scanner at high energy beam transport (HEBT), and the laser bunch shape monitor at medium energy beam transpo...