Safya Belghith

Learn More
We propose an estimator for nonlinear systems with unmatched unknown inputs and under measurement noise. The estimator design is based on the combination of observer design for descriptor systems, sliding-modes theory and adaptive control. The estimation of the measurement noise is achieved thanks to the transformation of the original system into a singular(More)
The paper proposes breaks for the permutation methods adopted in the chaos-based image cryptosystems. By a careful examination on the most chaotic image cryptosystems we can find that the permutation process constitute the main step or, in some cases, the only step to create the confusion. It can be applied on the pixels or on the pixel bits. A recently(More)
In this paper, the problem of nonlinear equalization is adressed. We use an algebraic approach which allows us to define the existence conditions of a left inverse, for a nonlinear system and therefore the equalization conditions. These existence conditions need the computation of the rank of some jacobian matrices. This approach is applied to a Volterra(More)
In this paper, a novel steganographic scheme is proposed based on chaotic map in the DCT domain. The proposed method apply the DCT on the cover image, scan the AC coefficients in a zigzag form from the least significant to the most significant one, this scan will lead us eventually to precise the embedding positions through a chaotic function as well as the(More)