In this paper, the vibration of composite cylindrical shell with piezoelectric layers in the interior and exterior surfaces is investigated. The composite shell without piezoelectric layers can be studied and compared the results with the results of other researchers, the cylindrical shell laminated with layers of piezoelectric vibration checked. The result is a three-dimensional elasticity equ...

The aim of this paper is the analytical solutions the family of rst-order nonlinear stochastic differentialequations. We dene an integrating factor for the large class of special nonlinear stochasticdierential equations. With multiply both sides with the integrating factor, we introduce a deterministicdierential equation. The results showed the accuracy of the present work.

An analytical solution for calculating the residence time of fluid flowing toward a pumping well in an unconfined aquifer has been developed. The analytical solution was derived based on a radial, steady-state, Dupuit-Forchheimer flow model. The resulting integral expression involved computing the imaginary error function, for which a simple series expansion is proposed. The validity of the ana...