Mark Asch

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The statistical properties of acoustic signals reeected by a randomly layered medium are analyzed when a pulsed spherical wave issuing from a point source is incident u p o n i t. The asymptotic analysis of stochastic equations and geometrical acoustics is used to arrive at a set of transport equations that characterize multiply scattered signals observed(More)
The present study is concerned with the properties of 2D shallow cavities having an irregular boundary. The eigenmodes are calculated numerically on various examples, and it is shown first that, whatever the shape and characteristic sizes of the boundary, irregularity always induces an increase of localized eigenmodes and a global decrease of the existence(More)
We consider for the wave equation the inverse problem of identifying locations of point sources and dipoles from limited-view data. Using as weights particular background solutions constructed by the geometrical control method, we recover Kirchhoff-, back-propagation-, MUSIC-, and arrival time-type algorithms by appropriately averaging limited-view data. We(More)
We are concerned in this work with simulations of the localization of a finite number of small electromagnetic inhomogeneities contained in a three-dimensional bounded domain. Typically , the underlying inverse problem considers the time-harmonic Maxwell equations formulated in electric field in this domain and attempts, from a finite number of boundary(More)
The statistical properties of acoustic signals reeected by a randomly layered medium are analyzed when a pulsed spherical wave issuing from a point source is incident upon it. The asymptotic analysis of stochastic equations and geometrical acoustics is used to arrive at a set of transport equations that characterize multiply scattered signals observed at(More)
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