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Ouadah N.,CDTA | Cadenat V.,Roche Holding AG | Cadenat V.,Toulouse 1 University Capitole | Lerasle F.,Roche Holding AG | And 5 more authors.
Advanced Robotics

This paper presents a multi-sensor-based control strategy allowing a mobile robot to safely navigate with respect to a given human being. Two sensors are embedded in our robot: a vision system that is able to detect and track the person of interest, and a RFID antennas belt that can locate the tag worn by the latter. Thus, our control strategy will be built using image features (when the user is visible) and RFID information (when not). In the first case, a robust visual servoing control will be designed, while in the second case a suitable RFID controller will be proposed. Experimental results demonstrate the efficiency of the proposed control strategy. © 2011 Koninklijke Brill NV, Leiden. Source

Boulkroune A.,Jijel University | Tadjine M.,ENP | M'saad M.,University of Caen Lower Normandy | Farza M.,University of Caen Lower Normandy
Control and Intelligent Systems

In this paper, one presents a unified adaptive fuzzy observer design framework for a class of uncertain nonlinear systems. The corrective term of the proposed observer involves a well-defined design function which is shown to be satisfied by the commonly used high-gain (HG)-based observers, namely the usual HG observers and the sliding mode observers together with their implementable versions. Without resorting to the strictly positive real condition or the filtering of the observation error, a proportional-integral law for updating the fuzzy parameters is proposed. The proportional part is used to deal with the fuzzy approximation errors and the external disturbances. Ultimately boundedness of the error signals in the closed-loop system is shown through Lyapunov's direct method. Source

Samira B.,DTISI | Hassina A.,DTISI | Latifa H.,ENP
International Conference on Signal Processing Proceedings, ICSP

Many data hiding algorithms have been proposed for the latest video codec H.264/AVC, most of them are based on the 4×4 luma DCT coefficients. However, for this kind of algorithms, the drift distortion is the main reason which limits the embedding capacity. Few methods have been proposed to compensate or eliminate the error propagation. Though, they are either non-blind, only detectable or need prior knowledge of the encoded blocks and thus cannot be used for real time broadcasting. In this paper we show that it is possible to reduce considerably the error propagation for real time applications. The proposed algorithm exploits the method of watermarking paired-coefficients in each block in order to bring the error to the middle of the block matrix. We evaluate the distortion caused by each paired-coefficient in order to give a watermarking priority to the pairs which introduce the minimum error. The proposed scheme offers a very good compromise between the video distortion, the increase in bitrate and the embedding capacity. © 2012 IEEE. Source

Boulkroune A.,Jijel University | Tadjine M.,ENP | M'Saad M.,University of Caen Lower Normandy | Farza M.,University of Caen Lower Normandy
Information Sciences

This paper presents an adaptive fuzzy observer for a class of uncertain nonlinear systems. More precisely, we propose a unified approach for designing such an observer with some design flexibility so that it can be easily adaptable and employed either as a high-gain or a sliding mode observer by selecting its gain appropriately. Additionally, we derive a suitable parameter adaptation law so that the proposed observer is robust with respect to ubiquitous fuzzy approximation errors and external disturbances. We also show that the observation error is ultimately bounded using a Lyapunov approach without having recourse to the usual strictly positive real (SPR) condition or a suitable observation error filtering. The effectiveness of the proposed observers is illustrated through two simulation case studies taken from the adaptive fuzzy control literature. © 2013 Elsevier Inc. All rights reserved. Source

Henini G.,University of Hassiba Ben Bouali Chlef | Laidani Y.,University of Hassiba Ben Bouali Chlef | Souahi F.,ENP | Hanini S.,Dr. Yahia Fares University Center of Medea
Energy Procedia

It is very well known at present that different industries agro-food sector generally produce considerable quantities of wastewater should be treated imperative for preserving the environment, and thus avoid a real danger to the ecosystem. These waters are usually loaded with in pollutants of organic nature. This study was motivated by the fact that no quantitative study concerning the physico- chemical behavior of Luffa cylindrica fibers, hence the idea to use the capacity of retention by adsorption of contaminants. In the first step, we studied the kinetics of adsorption (static adsorption of system phenol / fibers of Luffa cylindrica) by using the model of pollution of the phenol as a method of analysis the UV spectrophotometry, in a second step we valued with quantification the adsorption isotherms obtained in relation to other commonly used isotherms (activated carbon / phenol) and a final step optimization of the phenomenon has been conducted, the results are widely presented and discussed taking into account the variation some physicochemical parameters. This work demonstrates and confirms the possibility of using Luffa cylindrica fibers for industrial treatment of wastewater for its advantageous features: natural fiber, economic, non-toxic, biodegradable, filter, fuel and incinerated, ... etc. © 2012 Published by Elsevier Ltd. Source

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