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A new approach is proposed to solve for the eigen-values and eigen-functions of circular plates with circular holes by using the Rayleigh Ritz Method. In this method, the spatial solution is expanded into separable functions in terms of polar coordinates. While trigonometric functions are used along the circumferential direction, the Boundary Characteristic Orthogonal Polynomials build the radial shape functions. Written in terms of the assumed functions, the potential and kinetic energies are modified in order to account for the holes. Although the proposed approach is applicable for plates with different boundary conditions and different hole shapes, the free vibration of a clamped circular plate with circular holes is considered in the present study. The edges of the holes are free. Four different case studies are carried out. The results of the Rayleigh Ritz Method are compared with those available in the literature.

After a long “incubation” period, MEMS are finally strongly coming out on the marked. The integrated telemetry and the photo-voltaic power source are among the attractive features of the integrated MEMS applications. The tendency is more and more seen to small integrators, which use OEMs and build systems for market demanded applications. However, the products offered by the market at this time are mostly limited to static detection or inertial systems. The temperature range of the dominant applications quite significantly limits the measurement capabilities of the system. Aerospace systems are not necessary falling within the normal temperature range. The need of enhanced performance and safety of the gas turbine engines require pressure measurements at temperature that exceed 500 °C. Apart from the physics, the principle of measurement, fabrication technology, signal data processing, packaging represents a challenging task.

Automotive suspensions invariably exhibit asymmetric damping properties in compression and rebound, which is partly attributed to asymmetric damping and in-part to the suspension linkage kinematics together with tire lateral compliance. Although automotive suspensions have invariably employed asymmetric damping, the design guidelines and particular rationale for such asymmetry has not been explicitly defined. The influences of damper asymmetry together with the suspension kinematics and tire lateral compliance on the dynamic responses of a vehicle are investigated analytically under bump and pothole excitations, and the results are interpreted in view of potential design guidance. A quarter-car kineto-dynamic model of the road vehicle employing a double wishbone type suspension comprising a strut with linear spring and multiphase asymmetric damper is formulated for the analyses.