Batna, Algeria

University of Khenchela
Batna, Algeria
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Aouidane L.,University Mohamed Khider of Biskra | Aouidane L.,University of Khenchela | Belhamra M.,University Mohamed Khider of Biskra
Journal of African Earth Sciences | Year: 2017

The Remila Plain is a synclinal structure in northeast Algeria, situated within a semi-arid climate zone and composed of Mio-Pliocene-Quaternary deposits. Within the syncline, the Plio-Quaternary aquifer is the main source of drinking water for cattle and for agricultural irrigation water. This work aims to investigate the origin of groundwater mineralization and to identify the primary hydrogeochemical processes controlling groundwater evolution in the Remila aquifer. A total of 86 water samples from boreholes were analyzed for major, minor and stable isotopes (18O, 2H) over three seasons: first during low water levels in 2013, second during high water levels in 2014 and third for stable isotopes during low water levels in 2015. The analysis showed that the aquifer is controlled by five principal geochemical processes: (I) the dissolution of evaporite rocks, (II) cation exchange and reverse exchange reactions, (III) congruent dissolution of carbonates (calcite, dolomite) coupled with the dissolution of gypsum and calcite precipitation, (IV) sulfate reduction under anaerobic conditions, and (V) saltwater intrusion in the northeastern Sabkha plains. The 18O and deuterium concentrations in groundwater are very low, indicating that the aquifer is recharged by evaporated rainfall originating from the north slope of the Aurès Mountains which confirms that the aquifer is recharged in the southern part of the plain. © 2017 Elsevier Ltd

Hemam S.M.,University of Khenchela | Hioual O.,University of Khenchela
Proceedings of 2016 International Conference on Cloud Computing Technologies and Applications, CloudTech 2016 | Year: 2016

In this paper, we investigate the cloud service selection model by taking into account the load-balancing across different clouds. Indeed, a number of service providers offer similar services at various prices and performance levels which made a real decision-making problem in a service selection. This problem occurs in a multi cloud environment when we need to select a service by taking into consideration the preference of users (minimizing both cost and response time) and the requirement of the system (load balancing between clouds). In this work, we present our solution which allows to select a cloud service by taking into account the preferences of the user and also which allows to balance the load between different clouds. The proposed solution is based on the MCDA: Multi Criteria Decision Analysis and the Markov Chain Model. © 2016 IEEE.

Hemam M.,University of Khenchela | Hemam M.,University of Mentouri Constantine | Boufaida Z.,University of Mentouri Constantine
International Journal of Reasoning-based Intelligent Systems | Year: 2011

Domain ontologies are intended to provide a commonly shared understanding among several user communities. Concepts and their relationships are used to explicitly model the realworld phenomena that are of interest to users of specific domain. In practice, a set of a specificdomain applications use different representations of the same real-world entity due to various viewpoints, context and specific interest. In this paper, we are interested in the problem of representing an ontology in heterogeneous organisation by taking into account different viewpoints and different terminologies of various users, groups or even communities in the organisation. Such ontology, called Multi-Viewpoints Ontology, allows heterogeneity and consensus in a heterogeneous organisation. So, our goal is to propose a Multi-Viewpoints Ontology Web Language, which is an extension of OWL-DL language, to allow the multiviewpoints ontologies representation for the Semantic Web. Copyright © 2011 Inderscience Enterprises Ltd.

Derouiche F.,University of Mentouri Constantine | Derouiche F.,University of Khenchela | Bole-Feysot C.,University of Rouen | Naimi D.,University of Mentouri Constantine | Coeffier M.,University of Rouen
Biochemical and Biophysical Research Communications | Year: 2014

Background and aims Hyperhomocysteinemia (HHcy) is associated with cardiovascular diseases and is thought to induce endogenous oxidative stress and causes many cellular damages. Proteasome that degrades oxidized and ubiquitinated proteins can regulate the cellular response to oxidative stress. We aimed to investigate whether hyperhomocysteinemia induces oxidative stress and alters proteasome function and composition in heart and aorta tissues of rat. Methods and results To create hyperhomocysteinemia, male Wistar rats (Pasteur Institute-Algiers) were received daily intraperitoneal injections of dl-homocysteine (0.6-1.2 μM/g body weight) for 3 weeks. Biomarkers of oxidative stress (malondialdehyde (MDA), protein carbonyl (PC), superoxide dismutase (SOD) and catalase (CAT)) were first measured by biochemical methods and tissue damages by histological sections. Proteasome activities were quantitated using fluorogenic synthetic peptides; ubiquitinated proteins and proteasome subunits expression were then evaluated by SDS PAGE and Western blot analysis. We showed increased MDA and PC but decreased SOD and CAT levels both in plasma, heart and aorta accompanied by histological changes. A significant decrease of proteasome activities was observed in heart, whereas proteasome activity was not affected in aorta. However proteasome composition was altered in both tissues, as the accumulation of ubiquitinated proteins. Conclusion Data demonstrated an alteration of the ubiquitin-proteasome system in hyperhomocysteinemia as a result of accumulating oxidized and ubiquitinated proteins in response to oxidative stress. Further studies must be conducted to better understanding mechanisms responsible of proteasome alterations in hyperhomocysteinemia. © 2014 Elsevier Inc. All rights reserved.

Djelloul A.,University of Khenchela | Aida M.-S.,University of Mentouri Constantine | Bougdira J.,CNRS Jean Lamour Institute
Journal of Luminescence | Year: 2010

Undoped and aluminum-doped zinc oxide (ZnO) thin films have been grown on polycrystalline α-alumina substrates by ultrasonic spray pyrolysis (USP) technique using zinc acetate dihydrate and aluminum chloride hexahydrate (Al source) dissolved in methanol, ethanol and deionized water. A number of techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and photoluminescence (PL) were used to characterize the obtained ZnO thin films. It was seen that the orientation changed with increase in substrate temperature. During the ZnO deposition Zn source reacted with polycrystalline α-Al2O 3 substrate to form an intermediate ZnAl2O4 spinel layer. It has been interestingly found that the intensity of green emission at 2.48 eV remarkably increased when the obtained ZnO:Al films were deposited at 380 °C. The FTIR absorbance intensity of spectroscopic band at 447±6 cm-1 is very sensitive to oxygen sublattice disorder resulting from non-stoichiometry, which is consistent with the result of PL characterization. © 2010 Elsevier B.V. All rights reserved.

Bououden S.,University of Khenchela | Chadli M.,University of Khenchela | Allouani F.,University of Picardie Jules Verne | Filali S.,University of Mentouri Constantine
International Journal of Innovative Computing, Information and Control | Year: 2013

This paper introduces a new approach for designing an adaptive fuzzy model predictive control (AFMPC) using the Particle Swarm Optimization (PSO) algorithm. The system to be controlled is modeled by a Takagi-Sugeno fuzzy inference system whose parameters are identified using recursive least square algorithm. These parameters are used to calculate the objective function based on predictive approach and structure of RST controller. The controller design methodology is formulated as an optimization problem solved by PSO algorithm to obtain the optimal future control. The approach was applied for controlling two non linear systems CSTR and Tank system. The results are en- couraging compared with those obtained using the Proportional Integral-Particle Swarm Optimization (PI-PSO) and adaptive fuzzy model predictive control (AFMPC). © 2013 ISSN 1349-4198.

Benounis M.,University of Khenchela | Benounis M.,University of Guelma
Sensors and Actuators, B: Chemical | Year: 2015

A new phosphate-selective poly[vinylchloride-co-vinylacetate-co-vinylalcohol] membrane with Trioctyl-tin-chloride (Carrier I) and Methylenebis[dibromo(phenyl)stannane] (carrier II) were proposed to invert the Hofmeister behaviour and to form strong complexes with the hydrophilic target anion. Plasticizers effect and selectivities for phosphate over many common anions, such as nitrate, chloride, fluoride and bicarbonate, at pH 3.6 are studied for several membranes formulations. We show that the phosphate selectivity is better and comparable to required values for membranes based on tin compound plasticized with low dielectric constant solvent and the sensor exhibits a LOD of about 6.5 × 10-08 M with a linear response towards phosphate ion over a wide concentration range of 10-5-10-3 M. The response times and lifetime of copolymer-membranes-optodes were studied. The response times of the membranes with copolymer based on carriers I and II were 20 s and 40 s, when changing from 10-4 M phosphate to 10-3 M. The lifetime of the copolymer-based-membrane was higher than that of PVC-based-membrane with the same carrier and the optode is adequate for phosphate ion detection in real water. © 2015 Elsevier B.V. All rights reserved.

Dadda N.,CNRS Laboratory of Crystallography, Nuclear Magnetic Resonance and Modelling | Dadda N.,University of Khenchela | Nassour A.,CNRS Laboratory of Crystallography, Nuclear Magnetic Resonance and Modelling | Guillot B.,CNRS Laboratory of Crystallography, Nuclear Magnetic Resonance and Modelling | And 2 more authors.
Acta Crystallographica Section A: Foundations of Crystallography | Year: 2012

The new crystal structure of 2-carboxy-4-methylanilinium chloride monohydrate was determined by X-ray diffraction and refined using three different electron-density models. In the first model, the ELMAM2 multipolar electron-density database was transferred to the molecule. Theoretical structure factors were also computed from periodic density functional theory calculations and yielded, after multipolar-atoms refinement, the second charge-density model. An alternative electron-density modelling, based on spherical atoms and additional charges on the covalent bonds and electron lone-pair sites, was used in the third model in the refinement versus the theoretical data. The crystallographic refinements, structural properties, electron-density distributions and molecular electrostatic potentials obtained from the different charge-density models were compared. As the number of variables refined in the different models is the same, the R factor is a good indicator of refinement quality. The R factor is best for multipolar modelling, presumably because of the greater flexibility and larger number of parameters to model the electron density compared to the spherical-charges model. The electrostatic potentials around the molecule show a high correlation coefficient between the three models. © 2012 International Union of Crystallography Printed in Singapore - all rights reserved.

Fouad A.,University of Khenchela | Boukhetela D.,Polytechnic School of Algiers | Boudjema F.,Polytechnic School of Algiers
International Journal of Control and Automation | Year: 2013

A new type controller, recurrent fuzzy neural networks-fuzzy-sliding mode controller (FRNN-FSMC), is developed for a class of large-scale systems with unknown bounds of high-order interconnections and disturbances. The main purpose is to eliminate the chattering phenomenon and to overcome the problem of the equivalent control computation. The FRNN-FSMC, which incorporates the recurrent fuzzy neural network (RFNN), fuzzy logic controller (FLC) and the SMC, can eliminate chattering using a fixed boundary layer around the switch surface. Within the boundary layer, where the FLC is applied, the chattering phenomenon, which is inherent in a SMC, is avoided by smoothing the switch signal. Moreover, to compute the equivalent controller, a feed-forward RFNN is used. The stability of the whole system is analyzed via the Lyapunov methodology. In this study, we propose an effective method to select some key controller parameters in an optimal manner by using the genetic algorithm (GA), so that a high performance of the overall system's response can be achieved. The effectiveness and efficiency of the proposed controller and optimization method were tested using highly interconnected nonlinear systems as examples.

Boumaza A.,University of Khenchela | Djelloul A.,University of Khenchela | Guerrab F.,University of Khenchela
Powder Technology | Year: 2010

The specific signatures of α-Al2O3 powders by a combination of X-ray diffraction (Rietveld analysis), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, thermal analysis (TG-DTA) and cathodoluminescence (CL) were investigated. Thus, α-alumina was prepared by calcination of boehmite or gibbsite at 1573K for 24h. The size of α-alumina crystallites obtained using boehmite precursor was smaller than that obtained using gibbsite precursor. The difference in oxygen vacancies (F+-centers) amount between α-Al2O3 powder obtained by calcination of gibbsite and boehmite was confirmed by CL spectra. Furthermore, the Ti3+ emission at 1.71eV is absent in α-Al2O3 powder obtained by calcination of gibbsite. CL has been demonstrated as a possible method for differentiation between the various α-alumina powders. © 2010 Elsevier B.V.

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