the bem is applied to the solution of the torsion problem of non-homogeneous anisotropic non-circular prismatic bars. the problem is formulated in terms of the warping function. this formulation leads to a second order partial differential equation with variable coefficients, subjected to a generalized neumann type boundary condition. the problem is solved using the analog equation method (aem)...

We present 3D prestack map time migration in closed form for qP-, qSV-, and mode-converted waves in homogeneous transversely isotropic media with a vertical symmetry axis (VTI). As far as prestack time demigration is concerned, we present closed-form expressions for mapping in homogeneous isotropic media, while for homogeneous VTI media we present a system of four nonlinear equations with four ...

The paper concerns the analysis of the correlations of wave fields propagating in heterogeneous media. We show that selected field-field correlations asymptotically propagate in non-scattering media, i.e., propagate as if the underlying medium was homogeneous. Such correlations are therefore good candidates for imaging strategies in heterogeneous media based on back-propagations in a homogeneou...

Wave propagation is an important characteristic for pattern formation and pattern dynamics. To date, various waves in homogeneous media have been investigated extensively and have been understood to a great extent. However, the wave behaviors in heterogeneous media have been studied and understood much less. In this work, we investigate waves that are spontaneously generated in one-dimensional ...

We report the design of microwave waveguide devices based on complementary media. Various kinds of waveguide devices that possess nearly 100% transmission efficiency are proposed, such as waveguide bends, splitters, connectors, and shifters. Compared with previous work on waveguide devices of low reflection and minimized distortion based on transformation optics, our transform media are homogen...