The static pull-in instability of beam-type micro-electromechanical systems is theoretically investigated. Two engineering cases including cantilever and double cantilever micro-beam are considered. Considering the mid-plane stretching as the source of the nonlinearity in the beam behavior, a nonlinear size-dependent Euler-Bernoulli beam model is used based on a modified couple stress theory, c...

Several techniques have been proposed for compensating the effects of the head-on or long-range beam-beam interaction. These include alternating crossing at several interaction points, electromagnetic wires, electron lenses, and superbunches. I discuss some prominent compensation schemes and their R&D status, with special emphasis on the LHC and its upgrade. 1 HISTORY AND PERSPECTIVE The beam-b...

for dynamic analyses of railway track structures, the algorithm of solution is very important. for estimating the important problems in the railway tracks such as the effects of rail joints, rail supports, rail modeling in the nearness of bridge and other problems, the models of the axially beam model on the elastic foundation can be utilized. for studying the effects of axially beam on the ela...

The ball and beam system is one of the most popular laboratory setups for control education. In this paper, we design a fuzzy PD cascade controller for a ball and beam system using Asexual Reproduction Optimization (ARO) technique. The ball & beam system consists of a servo motor, a grooved beam, and a rolling ball. This system utilizes a servo motor to control ball’s position on the beam. Chan...

In this paper, controlling the location of the tip of an L-shape beam under gravity field is investigated. The beam is covered with piezoelectric patches. The gravity filed moves the tip of beam downward and the actuators with induced voltage move the tip to the previous location. to optimize the best location and voltages for actuators, the particle swarm optimization algorithm code is develop...

The aim of the study was to examine the deformation modes and also degradation of an adhesively bonded rectangular cross section beam used in the automotive body structure. The study included: (1) performing new experimental investigations on the three-point bend behavior of a rectangular cross section beam made by adhesive bonding method. (2) developing a finite element (FE) model to predict t...

In this paper, a displacement-based, variationally consistent, two variable refined theory for shear deformable beams is presented. The beam is assumed to be of linearly elastic, homogeneous, isotropic material and has a uniform rectangular cross-section. In this theory, the beam axial displacement and beam transverse displacement consist of bending components and shearing components. The assum...

A two dimensional simulation study of the beam-beam interaction at SPEAR indicates that quantum fluctuations affecting the horizontal betatron oscillation play a critical role in the vertical beam blowup.

In a colliding beam storage ring, a major source of nonlinear resonance excitation resides in the beam-beam collisions as the stored beams repeatedly cross each other. During such collisions, particles in each beam see the electromagnetic field generated by the counter rotating beam. The beam-beam collisions therefore perturb the particle motion, causing-1. the transverse beam size to blow up a...

in this paper, the nonlinear conjugate map based on the conjugate hasofer-lind and rackwitz- fiessler (chl-rf) method is applied to evaluate the reliability index using first order reliability method of the embedded noanocompsite beam, which is made from polymer reinforced with carbon nanotubs (cnts). the structure is simulated with timoshenko beam model. the mori-tanaka model is applied for ca...