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Oujda, Morocco

Mekaoui S.,H+ Technology | Benhamed C.,H+ Technology | Ghoumid K.,Complexe University
WIT Transactions on Information and Communication Technologies | Year: 2013

This paper deals with a method using a specific class of neural networks whose learning phase is based on the Levenberg-Marquardt algorithm and which had been applied to the estimation of the traffic matrix (TM) of a large scale IP network. The neural network had been implemented with the help of the specific neural toolbox of the source software Matlab. Such neural networks are within the class of feed forward and recurrent types. The simulation tests have been processed on the available data base of the very reputed American observatory data base on the Internet of a very large scale IP network, the so-called Abilene network on both categories of neural networks. The simulated results using this method have been found to be very accurate as compared to one another. The static model converges rapidly but was less accurate in the estimation of the Traffic Matrix of such a kind of large IP System (the Abilene System) than the dynamic model which in this way earned the challenge of yielding a perfect estimation. © 2013 WIT Press.


Benmakhlouf T.,University of Science and Technology Houari Boumediene | Mekaoui S.,University of Science and Technology Houari Boumediene | Ghoumid K.,Complexe University
WIT Transactions on Information and Communication Technologies | Year: 2013

The main aim of this paper is concerned with modern telecommunications systems which involve modern methods of coding, encryption and decryption of speech signals. For a long time, for the transmission of a speech signal analog telecommunications systems have been used. Because of unexpected and unavoidable interference, wave fading perturbations and different kinds of noise occurring in the channel, it was not possible to detect and receive the same transmitted speech signal. Consequently, digital systems have steadily replaced the former. Here, we have simulated two blocks of such systems, namely the source coding block and the encryption/decryption block. We tested them by listening to the synthesized signals via headphones and using a simulation operated using Simulink of the source software Matlab. Although metallic in their tonalities, results were found to be acceptable. © 2013 WIT Press.


Mekaoui S.,University of Science and Technology Houari Boumediene | Tchoketchkebir S.,University of Science and Technology Houari Boumediene | Ghoumid K.,Complexe University
WIT Transactions on Biomedicine and Health | Year: 2013

The aim of the work presented in this paper is focused on the super-resolution technique for image processing in order to measure efficiently the diameter of the human artery. This work can find crucial applications in avoiding cerebral aneurisms if the physician has a good monitoring tool that can allow him to get this information early on the basis of the analysis of cerebral artery images. For this purpose, we have used a simulated artery home probe made of silicon and this model had been scanned by Phillips flat panel scanner (ALURA FD 20) with a resolution of 0.035mm. We have developed software based on the superresolution algorithm using the multi-scale wavelet analysis and able to reconstruct a high resolution image closest to the reality from a low resolution image. We have applied our image processing software to many images and have carried out a comparison with a super-resolution technique based on polynomial interpolation or B-splines interpolation and find out that our method yields better measurements of the artery diameter. © 2013 WIT Press.


Chaabelasri E.M.,University Mohammed Premier | Salhi N.,University Mohammed Premier | Elmahi I.,Complexe University | Benkhaldoun F.,LAGA
Physical and Chemical News | Year: 2010

This work concerns the numerical simulation of free flow on irregular bed. This flow can be described by the shallow water or Saint-Venant equations, written in conservative form. The numerical approximation model is based on non structured finite volume method coupled with dynamical adaptive mesh for spatial discretisation and a second order TVD Runge-Kutta scheme for temporal integration. The numerical flow at interface of each volume was evaluated by Roe approximate Riemann solver, extensible in second order by MUSCL approach. The source term was discretised by upwinding scheme of Vazquez. The resultant scheme is non-oscillatory and possesses conservation property required by the well balanced schemes. The precision, robustness and benefics in CPU time have been demonstrated over numerical tests including the principal's hydraulics problems such as: flood wave propagation, hydraulic jump and transcritical flow over variable bed.


Ouariach A.,Complexe University | Ghoumid K.,Complexe University | Malek R.,Complexe University | El Moussati A.,Complexe University | And 2 more authors.
IET Optoelectronics | Year: 2016

In this study, the authors present the design, fabrication and characterisation of a filter multiband tunableconsequence of a convolution product of two transfer functions. The device consists of two cavities arranged intandem and realised in integrated optics. The second cavity is 10% shorter than the first one. These maximas oftransmission are slightly moved away than those of the first one. The choice of the lengths of both close but unevencavities put in the profit a Vernier effect between the two spectral characteristics the purpose of which is to increasethe free spectral range (FSR), and therefore the tuning range. The filter design is discussed and its performance isintroduced using measurements and simulations. Consequently, the process is validated by the design of a dual-bandfilter with the resulting FSR multiplied by a factor of six as compared with that of a single Fabry-Perot. These resultswere verified theoretically and experimentally. © The Institution of Engineering and Technology 2016.

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