Gyroscopes are used as rotation rate sensors. Conventional gyroscopes are heavy and bulky, which creates important problems regarding their usage in different applications. Micro-gyroscopes have solved these problems due to their small size. The beam micro-gyroscope is one of the popular types of inertial sensors. Their small dimensions and low energy consumption are key reasons for their popul...

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...

We derive an asymptotically accurate formula for the beam waist of ultrashort, tightly focused fundamental linearly polarized, radially polarized, and azimuthally polarized modes in free space. We compute the exact beam waist via numerical cubature to ascertain the accuracy with which our formula approximates the exact beam waist over a broad range of parameters of practical interest. Based on ...

We define the accumulated Gouy phase shift as the on-axis phase accumulated by a Gaussian beam in passing through an optical system, in excess of the phase accumulated by a plane wave. We give an expression for the accumulated Gouy phase shift in terms of the parameters of the system through which the beam propagates. This quantity complements the beam diameter and the wave-front radius of curv...

The effect on the Stokes parameters of a Gaussian Schell model beam on propagation in free space is studied experimentally and results are matched with the theory [X. H. Zhao, et al. Opt. Express 17, 17888 (2009)] that in general the degree of polarization of a Gaussian Schell model beam doesn't change on propagation if the three spectral correlation widths δ xx, δ yy, δ xy are equal and the be...

A procedure for global beam shaping by modifying some global spatial parameters characteristic of the beam is proposed. This method is based on the generation of a nonuniformly polarized beam using a Mach-Zehnder system with two suitably shaped intensity transmittances and orthogonal linear polarizers. The changes in beam quality and kurtosis parameters after a linear polarizer placed at the ou...

The use of machine modeling and beam simulation programs for the control of accelerator operation has become standard practice. The success of a model-based control operation depends on how the parameter to be controlled is measured, how the measured data is analyzed, how the result of the analysis is interpreted, and how a solution is implemented. There is considerable interest in applying exp...

recently, a large amount of studies have been related to nonlinear systems with multi-degrees of freedom as well as continuous systems. the purpose of this paper is to optimize passive vibration absorbers in linear and nonlinear states for an euler-bernoulli beam with a nonlinear vibratory behavior under concentrated moving load. the goal parameter in the optimization is maximum deflection of t...

A semi-analytical method is used to illustrate the behavior of a multimodal nonlinear electromechanical system which is under base-excitation. System is considered as piezo-ceramic patches attached to a cantilever beam coupled to a resistive load. The cantilever beam is modeled as a nonlinear Timoshenko beam using Assumed Mode method and equations of motion are derived through Lagrange's equati...