Jelel Ezzine

A new step-in-place locomotion interface for virtual environment with large display system

The project presents a new locomotion interface for virtual environment with large display system. Users will be able to direct and control the traveling in the VE by in-place stepping and turning actions. Using a turntable technology, Visual feedback is continuously provided though the use of screen of limited size.

On exact convergence results of adaptive filters: the finite alphabet case

Abstract This paper introduces a tailored approach for the convergence analysis of adaptive filters governed by the LMS algorithm. The finite alphabet input case is considered, which corresponds to real digital transmission contexts. Complete and rigorous proofs for almost sure and mean-square convergences are provided without any constraining independence assumptions on the observation vector. An exact and useful bound of the critical step size is presented. Exact transient performances such as critical step size, speed of transient decrease, optimal step size and directionality of convergence, are deduced.

Secure Communication Using IFS: Almost Sure and Mean Square Stability Approaches

A new secure communication system is presented in this paper. The main idea is based on the use of a certain class of jump linear system (JLS), namely random iterated functions system (RIFS). The security algorithm is enhanced by random switching rules between several linear and affine subsystems. The synchronization between the sender and the receiver is assured by two systematic procedures that evolve second moment and the almost sure stability. An example is given in the end of the paper to illustrate the efficiency of the developed theory.

On exact performances of adaptive Volterra filters: the finite alphabet case

This paper deals with the analysis of adaptive Volterra filters in the finite alphabet inputs case. A tailored approach for this context is presented. Complete and rigorous mean square analysis are provided without any constraining independence assumption. An exact transient and steady state performances such as critical step size, rate of transient decrease, optimal step size and excess mean square error, are deduced.

A Novel Way to Secure Communication: Large Scale IFS Approach

In this paper, we propose a new generic cryptosystem based on the use of large scale iterated function systems. In order to increase the complexity of the encryption scheme, the dimension of transmitter is augmented. The suitable formulation is given. The synchronization between the sender and the receiver is assured by almost sure stability.

Performance analysis of adaptive Volterra filters in the finite-alphabet input case

This paper deals with the analysis of adaptive Volterra filters, driven by the LMS algorithm, in the finite-alphabet inputs case. A tailored approach for the input context is presented and used to analyze the behavior of this nonlinear adaptive filter. Complete and rigorous mean square analysis is provided without any constraining independence assumption. Exact transient and steady-state performances expressed in terms of critical step size, rate of transient decrease, optimal step size, excess mean square error in stationary mode, and tracking nonstationarities are deduced.

Genetic Algorithm Based-Computation of the Lyapunov Exponent for Jump-Parameter Systems

Abstract Using the Lyapunov exponent, simple tests for almost-sure stability of discrete time jump parameter systems are intoduced. This stability criterion is tackled using genetic algorithm and a novel genetic almost-sure stability algorithm is proposed. The nature of genetic algorithms renders the approach suitable for optimizing nonsmooth objectives such that involving approximations of the Lyapunov exponent. Two numerical examples are given to illustrate the strengths of the introduced technique and a comparaison with an approach based on the bilinear matrix technique is considered.

On the Brockett-Blankenship Embedding of Two-Form Jump Linear Systems and Their Riccati Transformation

Abstract Jump Linear (JL) control systems, are linear dynamical systems whose parameters jump randomly among a finite set of realizations. This class of models can be used to describe a variety of systems, such as fault Tolerant Control systems, failure Prone systems. Battle Management/Communication, Command, and Control systems, Flexible Manufacturing systems, Target Tracking systems. and last but not least Macroeconomic systems. This paper proposes the Brockett-Blankenship imbedding (BBE) as an adequate tool to simplify the manipulations of such important class of systems. To simplify even more, such manipulations, two algebras are introduced. Each algebra corresponds to a specific choice of the BBE. To illustrate the advantages of such embedding as well as their corresponding algebras, linear transformation of JL control systems is presented, especially the Riccati transformation. and key properties of this class of systems are revealed.