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In this paper, a fuzzy adaptive control system is investigated for a class of uncertain multi-input multi-output (MIMO) nonlinear systems with both unknown backlash hysteresis and unknown sign of the control gain matrix. To deal with the unknown sign of the control gain matrix, the Nussbaum-type function is used. In the designing of the fuzzy adaptive control scheme, we will exploit a decomposition property of the control gain matrix. To compensate the effects of the backlash, we require neither the knowledge of backlash parameters nor the construction of its inverse.

International audience; The Moving horizon approach is extended to a discrete linear systems with unknown inputs. The state and the unknown inputs are estimated via the optimal state estimation of singular systems. A numerical example is presented to illustrate the performance of the proposed filter.

International audience; In this paper, the moving horizon recursive state estimator for linear singular systems is derived from the least squares estimation problem. It will be shown that this procedure yields the same state estimate as the Kalman filter for descriptor systems if the noise is Gaussian. A numerical example is presented to prove the performance of the proposed filter.

The function of a sensory system is to transduce and relay sensory information in a constant and reproducible manner. However, in the olfactory processing of certain steroids this precept of sensory constancy does not appear to apply. Using threshold testing, psychometrics, and electrophysiological techniques, we investigated the effects of a repetitive exposure protocol on the response to androstadienone. Androstadienone is a steroid found in human secretions that has been widely proposed as a candidate for a human pheromone. The detection threshold, hedonic perception, and evoked potential response all changed following repetitive exposure to androstadienone and not to a control odorant, benzaldehyde. Furthermore, the exposure-dependent changes in evoked potentials exhibited a gender dimorphism in which there were changes in the later components of the evoked potentials specific to women. These components have been associated with cognitive and perceptual operations. This 'learning' to smell a compound found in sweat may be related to biological signaling.

National audience; Dans cet article, l'approche d'estimation à horizon glissant pour les systèmes singuliers est dérivée du problème de l'estimation par moindres carrés. Nous montrons que le filtre obtenu par cette approche est équivalent au filtre de Kalman pour les systèmes singuliers dans le cas où le bruit est gaussien. Un exemple numérique est présenté pour prouver la performance du filtre proposé.

In this paper, an adaptive feedback controller with observer is developed for a class of chaotic systems. This controller does not need the availability of state variables. It can be used for tracking a smooth orbit that can be a limit cycle or a chaotic orbit of another system. This adaptive feedback controller is constructed with H∞ control technique. Based on Lyapunov stability theorem, the proposed adaptive feedback control system can guarantee the stability of whole closed-loop system and achieve the H∞ tracking performance as well. To demonstrate the efficiency of the proposed scheme, two well-known chaotic systems namely Duffing-Holmes system and Lur'e-like system are considered as illustrative examples.