in this paper deflection and free vibration of sandwich panel is studied. the core of sandwich panels is made of hexagonal honeycomb and faces are made of two different materials of carbon fiber reinforced plastic and k-aryl/epoxy covering. the governing equations are deduced from the first order sheer deformation theory (fsdt) and they are solved using generalized differential quadrature metho...

The input electrical impedance behaves as a capacitive when a piezoelectric transducer is excited near its resonance frequency. In order to increase the energy transmission efficiency, a series or parallel inductor should be used to compensate the capacitive impedance of the piezoelectric transducer. In this paper, the effect of the series matching inductor on the electromechanical characterist...

Electromechanical properties of the cellular polypropylene ferroelectret films (EMFIT) evidence their high potential for the air-coupled ultrasonic applications. The disadvantage with respect to their low coupling factor could be compensated by the extremely low acoustic impedance. A figure of merit is proposed to compare and estimate piezoelectric materials intended for the air-coupled ultraso...

This thesis describes the potential use of re-entrant microwave resonant three-dimensional cavities as low-loss electrical component in strongly coupled electromechanical systems. In particular , I have investigated radiative processes as a loss mechanism of a re-entrant cavity in a geometry similar to those used in electromechanical experiments undertaken by the Lehnert lab. First, I present t...

this paper presents a mathematical model for the vibration analysis of a three-component piezoelectric force sensor. the cubic theory of weakly nonlinear electroelasticity is applied to the model for describing the electromechanical coupling effect in the piezoelectric sensing elements which operate in thickness-shear and thickness-stretch vibration modes. hamilton's principle is used to d...

In this paper, the analytical solution of an electric and Volterra edge dislocation in a functionally graded piezoelectric (FGP) medium is obtained by means of complex Fourier transform. The system is subjected to in-plane mechanical and electrical loading. The material properties of the medium vary exponentially with coordinating parallel to the crack. In this study, the rate of the gradual ch...

We have studied thedielectric and electromechanical properties of pure and doped Pb(Zr0.53Ti0.47)O3thin films.Samples were prepared bya sol-gel method and werecalcined at temperatures of 700oC for two hours in a Pb-rich atmosphere.It was observed a negligible effect occurs during the tetragonal–rhombohedral transition in the preparedpure and doped PZT thin films.The optimal amount of electrical...