scattering problem for the corresponding wave field at the receiver locations. Depending on the difference beThe multidimensional inverse scattering problem for an tween the observed and the computed scattered waves, acoustic medium is considered within the homogeneous a new estimate of the medium model is obtained and a new estimate of the medium model is obtained and background Born approxima...

Fifth international conference on surface x-ray and neutron scattering. Abstract Grazing incidence x-ray surface scattering has been used to investigate liquid surfaces down to the molecular scale. The free surface of water is well described by the capillary wave model (< z(q)z(−q) >∝ q −2 spectrum) up to wave-vectors > 10 8 m −1. At larger wave-vectors near surface acoustic waves must be taken...

We present the application of the theory of Padé approximants to extending the perturbative solutions of acoustic wave equation for a three dimensional vertically varying medium with one interface. These type of solutions have limited convergence properties depending on either the degree of contrast between the actual and the reference medium or the angle of incidence of a plane wave component....

The complex dynamics that lead to the emergence of active regions on the Sun are poorly understood. One possibility is that magnetic structures (flux tubes, etc.) rise from below the surface by self induction and convection that lead to the formation of active regions and sunspots on the solar surface. For space weather forecasting, one would like to detect the subsurface structures before they...

The acoustic ducting effect by curved nonlinear gravity waves in shallow water is studied through idealized models in this paper. The internal wave ducts are three-dimensional, bounded vertically by the sea surface and bottom, and horizontally by aligned wavefronts. Both normal mode and parabolic equation methods are taken to analyze the ducted sound field. Two types of horizontal acoustic mode...

In this paper we study, via variational methods, the problem of scattering of time harmonic acoustic waves by an unbounded sound soft surface. The boundary ∂D is assumed to lie within a finite distance of a flat plane and the incident wave is that arising from an inhomogeneous term in the Helmholtz equation whose support lies within some finite distance of the boundary ∂D. Via analysis of an eq...

This paper collects together various facts about digital waveguide networks (DWN) used in acoustic modeling, particularly results pertaining to lossless scattering at the junction of N intersecting digital waveguides. Applications discussed include music synthesis based on physical models and delay effects such as artificial reverberation. Connections with Wave Digital Filters (WDF), ladder/lat...