Abou Bekr Belkaid University Tlemcen

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Tlemcen, Algeria
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Benramdane A.,Abou Bekr Belkaid University Tlemcen
Energy Sources, Part B: Economics, Planning and Policy | Year: 2017

Algeria is one of the oil-rich countries that may be affected by the so-called natural resource curse. Algeria is one of the most important producers and exporters of hydrocarbon products (oil and gas) in the world; its exports from this sector represent about 98% of its total exportation. The hydrocarbon sector represents about 40–45% of the total GDP. The country’s macroeconomic performance over the past decade has been solid because of the relatively high oil prices, combined with prudent macroeconomic policies. This study tries to test the impact of oil prices volatility on economic growth in Algeria applying a VAR model using annual data over the period 1970–2012. This study’s results indicate that the negative growth effects of oil price volatility offset the positive impact of oil boom; therefore, it is argued that oil price volatility, rather than abundance per se, drives the “resource curse” paradox in Algeria. © 2017 Taylor & Francis Group, LLC.


Seladji Y.,Abou Bekr Belkaid University Tlemcen
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2017

The polyhedral analysis is widely used for the static analysis of programs, thanks to its expressiveness but it is also time consuming. To deal with that, a sub-polyhedral analysis has been developed which offers a good tread off between expressiveness and sufficiency. This analysis is based on a set of directions which is defined statically at the beginning of the analysis. More the cardinality of Δ is big, more the precision of the result is high. Even if the set Δ is big, the sub-polyhedral analysis can be done in a linear time. The bottleneck is that to construct the resulting polyhedron with a large number of constraints (one constraints per direction) is time consuming. In this article, we present a minimization method that allows to deal with that, using the max plus pruning method. We demonstrate the efficiency of our method on some benchmarks. The first results are very encouraging. © Springer International Publishing AG 2017.


Seladji Y.,Abou Bekr Belkaid University Tlemcen
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2017

The polyhedral model is widely used for the static analysis of programs, thanks to its expressiveness but it is also time consuming. To cope with this problem, weak-polyhedral analysis have been developed which offer a good trade off between expressiveness and efficiency. Some of these analysis are based on templates which fixed the form of the program’s invariant. These templates are defined statically at the beginning of the analysis, without taking into account the dynamic of programs. Finding good templates is a difficult problem. In this article, we present a method that uses the Principal Component analysis to compute an interesting template. We demonstrate the relevancy of the obtained templates on several benchmarks. © Springer International Publishing AG 2017.


Meftah K.,Abou Bekr Belkaid University Tlemcen
Journal of Hydraulic Research | Year: 2017

To model free-surface flows, a three-dimensional model is developed using a new approach where the horizontal velocity components are projected onto a basis of functions depending on the vertical coordinate z. The choice of this basis and the number of its terms depend on the physical problem and the desired precision. The vertical velocity component and the non-hydrostatic pressure are analytically determined. The integration of the variational form of main flow equations with an adequate choice of test functions transforms the three-dimensional model in a two-dimensional model. The finite element method using a two-dimensional mesh is used to solve the problem. This model is stable and robust because it does not use a mesh in the vertical direction. It is also accurate as the functions that best fit the physical nature of the flow can be directly introduced. The application of the proposed model to flows in curved channels is given. © 2016 International Association for Hydro-Environment Engineering and Research.


Benmouiza K.,Abou Bekr Belkaid University Tlemcen | Cheknane A.,University of Laghouat
Energy Conversion and Management | Year: 2013

In this paper, we review our work for forecasting hourly global horizontal solar radiation based on the combination of unsupervised k-means clustering algorithm and artificial neural networks (ANN). k-Means algorithm focused on extracting useful information from the data with the aim of modeling the time series behavior and find patterns of the input space by clustering the data. On the other hand, nonlinear autoregressive (NAR) neural networks are powerful computational models for modeling and forecasting nonlinear time series. Taking the advantage of both methods, a new method was proposed combining k-means algorithm and NAR network to provide better forecasting results. © 2013 Elsevier Ltd. All rights reserved.


Houari A.,Abou Bekr Belkaid University Tlemcen
European Journal of Physics | Year: 2013

In this paper, using the Lambert W function, I derive closed-form analytical expressions for the decay constant of an exponentially decaying process and the time constant of a process subject to a linear resistive force. Similarly, I derive closed-form analytical formulae for the electrical resistivity of a metal and the temperature of a thermionic emitter material. Besides their theoretical importance, the results obtained will be of interest to teachers involved in undergraduate physics experiments. © 2013 IOP Publishing Ltd.


Houari A.,Abou Bekr Belkaid University Tlemcen
European Journal of Physics | Year: 2013

I show that one can obtain an exact analytical expression for the viscosity of a liquid by solving the equation of motion for a spherical ball falling through it. I also deduce an approximate analytical relationship suitable for an experimental determination of the viscosity of liquids. © 2013 IOP Publishing Ltd.


Houmat A.,Abou Bekr Belkaid University Tlemcen
Composite Structures | Year: 2012

The geometrically nonlinear free vibration of a composite rectangular plate with variable fiber spacing is investigated. The investigation is limited to a single ply composite having straight and parallel fibers. The fibers are distributed more densely in the central region where high stiffness is needed than in other regions. The assumptions of von Karman's nonlinear thin plate theory are made. The problem is solved numerically using the hierarchical finite element method. The nonlinear equations of free motion are mapped from the time domain to the frequency domain using the harmonic balance method. The resultant nonlinear equations are solved iteratively using the linearized updated mode method. Results for the fundamental linear and nonlinear frequencies are obtained for simply supported and clamped composite square plates with three variable distributions of E-Glass, Graphite, and Boron fibers in Epoxy matrices. The efficiency of the hierarchical finite element procedure is demonstrated through convergence and comparison with published data. The variable fiber spacing, fiber volume fraction, type of fiber material, and boundary conditions are shown to influence the hardening behavior. © 2012 Elsevier Ltd.


Houmat A.,Abou Bekr Belkaid University Tlemcen
Composite Structures | Year: 2013

The geometrically nonlinear free vibration of laminated composite rectangular plates with curvilinear fibers is investigated. The assumptions of Von Kármán's nonlinear thin plate theory are made. The problem is solved numerically using the hierarchical finite element method. The nonlinear equations of free motion are mapped from the time domain to the frequency domain using the harmonic balance method. The resultant nonlinear equations are solved iteratively using the linearized updated mode method. Results for the fundamental linear and nonlinear frequencies and associated mode shapes are obtained for fully clamped laminated composite square plates composed of shifted curvilinear fibers. The efficiency and accuracy of the hierarchical finite element technique is demonstrated through convergence and comparison studies. Contour plots of fundamental linear and nonlinear frequencies as a function of fiber orientation angles are presented. The fiber orientation angles and layup sequence are shown to affect the degree of hardening and mode shapes. © 2013 Elsevier Ltd.


Houmat A.,Abou Bekr Belkaid University Tlemcen
European Journal of Mechanics, A/Solids | Year: 2014

A skew p-element is developed for the nonlinear free vibration of variable stiffness symmetric skew laminates. The governing equations are based on thin plate theory and Von Karman strains. The fundamental frequencies and normal modes are computed for fully clamped edge conditions. The equations of motion are derived using Lagrange's method. By employing the harmonic balance method, the transformation from time to frequency domain is facilitated. The nonlinear equations are solved using the iterative technique known as the linearized updated mode method. The numerical results are validated with the help of convergence tests and comparisons with published data. New results are presented for variable stiffness symmetric skew laminates with different fiber configurations showing the effects of variation in skew angle on frequency, normal mode, and degree of hardening. © 2014 Elsevier Masson SAS. All Right Reserved.

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