Lamb waves in plates and in cylindrical pipes have been the subject of extensive study, largely because they propagate great distances with little attenuation, and can therefore be used to detect flaws. In this paper we report finite element simulations and experimental studies of Lamb waves in steel bridge girder geometries. In our studies the Lamb waves are generated by PZT wafer-type transdu...

Guided waves based methods are widely used for damage detection and localization in metallic and composite structures. Success of the method application depends on many factors like sensors/actuators location, sensor electronic system design, sensor shape, frequency range of excitation waves and applied signal processing procedures. Authors developed new modified LISA and EFIT algorithms to sol...

Simple numerical and graphmal procedures are described for the calculation of the imperfect gas effects on the properties of steady and unsteady one-32.msnsions.l isentropic flows, the Prandtl-Meyer expansion round a corner and normal end oblique shock waves. The fun&mental equatmns of each type of flow have been put into a form in which they may be solve2 usmi: the published tables of the equi...

We present an overview of the relation between mantle dynamics and plate tectonics, adopting the perspective that the plates are the surface manifestation, i.e., the top thermal boundary layer, of mantle convection. We review how simple convection pertains to plate formation, regarding the aspect ratio of convection cells; the forces that drive convection; and how internal heating and temperatu...