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Brest, France

Jaulin L.,ENSTA Bretagne
Robotics and Autonomous Systems | Year: 2011

Interval methods have been shown to be efficient, robust and reliable to solve difficult set-membership localization problems. However, they are unsuitable in a probabilistic context, where the approximation of an unbounded probability density function by a set cannot be accepted. This paper proposes a new probabilistic approach which makes possible to use classical set-membership localization methods which are robust with respect to outliers. The approach is illustrated on two simulated examples. © 2011 Elsevier B.V. All rights reserved. Source

Martin E.,CNRS Laboratory for Thermostructural Composites | Leguillon D.,CNRS Jean Le Rond dAlembert Institute | Carrere N.,ENSTA Bretagne
International Journal of Solids and Structures | Year: 2012

The strength of an open holed composite plate subjected to tensile loading is analysed with the help of a coupled strength and energy criterion. Analytical and numerical models are used to determine the stress distribution and the energy released by crack nucleation in the vicinity of the hole. It is shown that the hole size effect can be described and that the crack length at nucleation both depends on the local geometry and the fracture characteristics of the specimen. These characteristic values can be identified with the help of traction tests performed on unnotched and holed samples. © 2012 Elsevier Ltd. All rights reserved. Source

Pastor D.,Telecom Bretagne | Socheleau F.-X.,ENSTA Bretagne
IEEE Transactions on Signal Processing | Year: 2012

In many applications, d-dimensional observations result from the random presence or absence of random signals in independent and additive white Gaussian noise. An estimate of the noise standard deviation can then be very useful to detect or to estimate these signals, especially when standard likelihood theory cannot be applied because of too little prior knowledge about the signal probability distributions. The present paper introduces a new scale estimator of the noise standard deviation when the noisy signals have unknown probability distributions and unknown probabilities of presence less than or equal to one half. The latter assumption can be regarded as to a weak assumption of sparsity. Applied to the detection of noncooperative radio-communications, this new estimator outperforms the standard MAD and its alternatives as well as the trimmed and winsorized robust scale estimators. The Matlab code corresponding to the proposed estimator is available at http://perso.telecom-bretagne.eu/pastor. © 2012 IEEE. Source

Bonnel J.,ENSTA Bretagne | Chapman N.R.,University of Victoria
Journal of the Acoustical Society of America | Year: 2011

This paper presents a single receiver geoacoustic inversion method adapted for low-frequency impulsive sources. It is applied to light bulb data collected during the Shallow Water 2006 experiment. The inversion is carried out by extracting dispersion curves from the received signal, and comparing them to simulated replicas. To achieve dispersion curve estimation in the time-frequency domain, modal separability is improved using a signal processing method called warping. The inversion scheme allows for a reliable estimation of the New Jersey Shelf sediment properties (compressional sound speed and density). It also provides an accurate estimation of the source/receiver range. © 2011 Acoustical Society of America. Source

A method of calibration of a navigation and pointing system (

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