the monte carlo method can be used to describe any technique that approximates solutions to quantitative problems through statistical sampling. this method is considered to be the most accurate method for dose calculation in radiotherapy. for complete modeling of a linear accelerator, it is required that the manufactured information covers all data, but some data such as primary electron energy...

the modulation response, relative intensity noise and frequency noise characteristics of qd lasers are investigated theoretically, in presence of an additional optical pumping. it is revealed that the modulation response of qd laser enhances under additional optical beam. by small signal analysis of the carriers' and photons' rates, it is proposed that by injecting excess carriers to ...

In this paper, the dynamic response of resonating nano-beams is investigated using a strain gradient elasticity theory. A nonlinear model is obtained based on the Galerkin decomposition method to find the dynamic response of the investigated beam around its statically deflected position. The mid-plane stretching, axial residual stress and nonlinear interaction due to the electrostatic force on ...

In this paper, the stability of a functionally graded magneto-electro-elastic (FG-MEE) micro-beam under actuation of electrostatic pressure is studied. For this purpose Euler-Bernoulli beam theory and constitutive relations for magneto-electro-elastic (MEE) materials have been used. We have supposed that material properties vary exponentially along the thickness direction of the micro-beam. Gov...

in this paper, the operation of helix traveling wave tube in interaction region is investigated by using a three dimensional large signal lagrangian model in frequency domain. the complete simulation of these tubes is essential for optimum design and minimum manufacturing cost. this 3d code can compute interception current (or current losses ), beam radius changes in interaction region and the ...

In this paper, size dependent beam type peizoelectric energy hardvester is investigated. For this goal, first nonlinear formulation of isotropic piezoelectric Euler-Bernoulli nano-beam is developed based on the size-dependent piezoelectricity theory then special beam type piezoelectric energy hardvester is probed for different parameters. Basic nonlinear equations of piezoelectric nano-beam are...

In this paper, the shape influence of piezoelectric beams including triangle, trapezoid, rectangle, inverted trapezoid, convex parabola, concave parabola, and comb-shaped (a combination of two triangular beams with a connector of 4 mm length) are addressed and analyzed by FEM. The analysis is performed for a bimorph piezoelectric beam. The analyzed parameters include the beam length, thickness ...