Kessal A.,University of Bordj Bou Arreridj |
Rahmani L.,Ferhat Abbas University Setif
ISA Transactions | Year: 2013
This paper presents a systematic procedure to compute the gains of sliding mode controller based on an optimization scheme. This controller is oriented to drive an AC-DC converter operating in continuous mode with power factor near unity, and in order to improve static and dynamic performances with large variations of reference voltage and load. This study shows the great influence of the controller gains on the global performances of the system. Hence, a methodology for choosing the gains is detailed. The sliding surface used in this study contains two state variables, input current and output voltage; the advantage of this surface is getting reactions against various disturbances-at the power source, the reference of the output, or the value of the load. The controller is experimentally confirmed for steady-state performance and transient response. © 2013 ISA.
Bentabet A.,University of Bordj Bou Arreridj
Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms | Year: 2011
The aim of this paper is to determine the best theoretical way (stochastic or analytic) to use in the study of the range of penetration and the backscattering coefficient of electron impinging in solid target, by adopting the same input in the form of collision cross-sections. For this purpose, differential elastic cross sections has been calculated by using our semi-empirical model [A. Bentabet, Z. Chaoui, A. Aydin, A. Azbouche, Vacuum 85 (2010) 156]; and that of inelastic cross sections has been calculated by using Gryzinski's excitation function. Moreover, in stochastic case, the obtained quantities are calculated by using both Monte Carlo schemes based on continuous slowing down approximation (CSDA) and on individual electron scattering events methods. © 2011 Elsevier B.V. All rights reserved.
Daoud S.,University of Bordj Bou Arreridj
Computational Materials Science | Year: 2015
Recently, L. Shi, Y. Duan and L. Qin have published a paper in Computational Materials Science 50 (2010) 203-210. They have studied the pressure induced phase transition and structural, electronic and elastic properties of TlX (X = N, P, As) compounds using the plane-wave pesudopotential (PW-PP) method. But it is to be noted that the numerical values of the average (vm ) wave velocities, and the Debye temperature θD of TlX (X = N, P, As) semiconductors obtained by Shi et al. (2010) seem to be inaccurate.In the present work, we have recalculated and gave the right numerical values of the average (vm ) wave velocities and the Debye temperature θD of TlX (X = N, P, As) semiconductors, based on the lattice parameters and the elastic constants obtained in their work. © 2015 Elsevier B.V.
Boubetra A.,University of Bordj Bou Arreridj
International Journal of Digital Content Technology and its Applications | Year: 2010
We are now well into the decade of an era in which simulation has become a most widely used technique, extensively applied in such diverse areas as social systems and space developments. In particular, this paper is devoted to exploring the impact of computer simulation on the social sciences. This article briefly reviews the use of simulation in sociology and goes on to consider in more detail specific areas such as system dynamics, cellular automata, simulation of social networks and organizations. It concludes with a consideration of the role of simulation in constructing agent-based models based on theories or social phenomena of social systems and it shows how an Agent Based Social Simulation might be implemented.
Bentabet A.,University of Bordj Bou Arreridj
International Journal of Modeling, Simulation, and Scientific Computing | Year: 2016
The purpose of this work is to determine the best analytical approximation of the differential cross-sections, used in Monte Carlo simulation, to study the electron and positron slowing down in solid targets in the energy range up to 10(Formula presented.)keV. For this, our comparative study has been carried out on the angular distribution of the scattering angle, the elastic total and the first transport cross-sections which are the essential quantities used generally in both the electron and the positron transport studies by using either stochastic or deterministic methods. Indeed, the obtained results using the relativistic partial wave expansion method and the backscattering coefficient (BSC) experimental data are used as criteria to evaluate the used model. © 2016 World Scientific Publishing Company