A boundary condition is developed that generalizes the author's earlier results and embodies the effect of multiple scatter for acoustic reflection on a rough surface. The size of the roughness is assumed to be sufficiently small in comparison with the wavelength. Both induced radiating dipoles and radiating sources are taken into account. The resu...
L'article formule un certain nombre des hypothèses qui déterminent la démarche de recherche en informatique musicale des auteurs. Plus que la production même des sons par un système de synthèse approprié, l'informatique musicale est abordée à un niveau qui semble essentiel ; celui du rapport instrumental, déterminant dans la manière dont les sons s...
Five monkeys belonging to the same family were equipped with miniature VHF, FM transmitters. The calls of each monkey were transmitted to five FM receivers and recorded on a multitrack tape recorder. The animals released in their usual enclosure were recorded during different activities: awakening, falling asleep, resting, feeding, alarming, etc. I...
A method of acoustic probing of an inhomogeneous plane stratified medium is discussed. The impedance profile is reconstructed from a time‐domain analysis of the pressure reflected when this medium is illuminated by a known pulse. This analysis is made from an exact integral formulation in an iterative manner by means of the optimization theory. At ...
The scattering of a transient acoustic Pwave by a two‐dimensional inhomogeneous fluid target is studied. An exact time‐domain formulation of the pressure is introduced and discretized. Discrete pressures are then computed by marching on in time and space. The convergence of this step by step procedure is examined numerically. Comparisons are made i...
This article is addressed to the idea of developing new instrumental models for digital sound synthesis. These models take two forms : 1) Input devices that capture physical gestures and react to the gestures under program control ; 2) sound synthesis techniques based on the simulation of physical sound producing mechanisms.
Five radiation and scattering problems in electromagnetics and acoustics are successively investigated to illustrate the interest and drawbacks of iterative solutions with respect to conventional direct ones, if they exist. All these solutions are based upon integral formulations of the fields. The iterative ones are in general developed from two c...
An ultrasonics diffraction tomography method is discussed that images cylindrical inhomogeneous fluid targets located in a fluid environment. This method is based on an exact model of the interaction between a compressional plane wave and the target (multiple scattering is not neglected). First the theoretical background is summarized. Then numeric...
Wind instrument provide interesting hydrodynamical systems where non-linearities are importantbut well localized. A simple analysis shows that these systems should undergo Feigenbaum-typeroute to chaos, with a cascade of period doublings. Experiments have been performed with anacoustical resonator and an "artificial" excitation (nonlinearities cont...
In this paper, we introduce a novel theory called the fuzzy structure theory. In a first part, we present theoretical elements of a probabilistic modeling of structural fuzzy in linear dynamic analysis of complex mechanical systems. The structural fuzzy is defined as the set of minor subsystems that are connected to the master structure but are not...
