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    1ères journées nationals d’étude sur la chimie théorique et ses applications JCTA1-21
    (Université de Khenchela, 2021-12-13) Lekmine Farid
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    A Low Complexity Parametric DFT and DHT -Based OFDM Transceivers
    (Fourth International Conference on Technological Advances in Electrical Engineering (ICTAEE’23.), 2023-05-24) CHERGUI Laid; BOUGUEZEL Saad
    In this paper, we design new efficient and fast orthogonal frequency division multiplexing (OFDM) transceivers by introducing parametric discrete Fourier and Hartley transforms. We experimentally show that, for a specific value of the parameter and for various signal-to-noise ratios and modulation schemes such as binary phase shift keying (BPSK), quadratic PSK (QPSK), 16 quadratic amplitude modulation (QAM) and 64QAM, the resulting OFDM transceivers based on these transforms achieve performance in terms of bit error rate similar to that of the existing OFDM transceivers. The compatibility of the proposed OFDM modulators with the conventional DFT-based OFDM demodulator is also experimentally verified. In addition, compared to the existing OFDM transceivers, we show that the computational complexity of the proposed OFDM transceivers is significantly reduced.
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    A Spider Monkey Optimization Based on Beta-Hill Climbing Optimizer for Unmanned Combat Aerial Vehicle (UCAV)
    (MDPI, 2023-03-03) Fouad Allouani, Abdelaziz Abboudi ,Xiao-Zhi Gao, Sofiane Bououden, Ilyes Boulkaibet, Nadhira Khezami and Fatma Lajmi
    Unmanned Combat Aerial Vehicle (UCAV) path planning is a challenging optimization problem that seeks the optimal or near-optimal flight path for military operations. The problem is further complicated by the need to operate in a complex battlefield environment with minimal military risk and fewer constraints. To address these challenges, highly sophisticated control methods are required, and Swarm Intelligence (SI) algorithms have proven to be one of the most effective approaches. In this context, a study has been conducted to improve the existing Spider Monkey Optimization (SMO) algorithm by integrating a new explorative local search algorithm called BetaHill Climbing Optimizer (BHC) into the three main phases of SMO. The result is a novel SMO variant called SMOBHC, which offers improved performance in terms of intensification, exploration, avoiding local minima, and convergence speed. Specifically, BHC is integrated into the main SMO algorithmic structure for three purposes: to improve the new Spider Monkey solution generated in the SMO Local Leader Phase (LLP), to enhance the new Spider Monkey solution produced in the SMO Global Leader Phase (GLP), and to update the positions of all Local Leader members of each local group under a specific condition in the SMO Local Leader Decision (LLD) phase. To demonstrate the effectiveness of the proposed algorithm, SMOBHC is applied to UCAV path planning in 2D space on three different complex battlefields with ten, thirty, and twenty randomly distributed threats under various conditions. Experimental results show that SMOBHC outperforms the original SMO algorithm and a large set of twenty-six powerful and recent evolutionary algorithms. The proposed method shows better results in terms of the best, worst, mean, and standard deviation outcomes obtained from twenty independent runs on small-scale (D = 30), medium-scale (D = 60), and largescale (D = 90) battlefields. Statistically, SMOBHC performs better on the three battlefields, except in the case of SMO, where there is no significant difference between them. Overall, the proposed SMO variant significantly improves the obstacle avoidance capability of the SMO algorithm and enhances the stability of the final results. The study provides an effective approach to UCAV path planning that can be useful in military operations with complex battlefield environments.
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    A Survey of Approaches for Curve Based Facial Surface Representations For Three-Dimensional Face Recognition
    (Ecole des ingénieurs, Telecom Lille 1, 0012-05-24) Aouragh Salima; Sbaa Salim; Taleb-Ahmed Abdelmalik
    The majority of face recognition methods using threedimensional data, either alone or in combination with two-dimensional intensity images are covered in existing survey papers. General 3D face representation has been extensively studied and various approaches have been proposed in the literature. This overview focuses on the class of researches exploiting curve concept to represent facial surface for three-dimensional face recognition using profile or contour curves. Challenges involved in estimating the surface by curves are also identified.
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    Analysis of Stresses on a Pre-cracked Cup of a Total Hip Prosthesis (THP)
    (2022) Meddour Belkacem; BREK Samir
    Zirconia is known as a bioceramic having properties which could make it a substitute material in prosthesis manufacturing field, in the other hand it presents a weak fracture toughness which is the main disadvantage. This work aims to analyze the mechanical behavior of a pre-cracked cup of a total hip prosthesis in severe circumstances by using numerical simulation. ABAQUS-6.8 as a numerical simulation software was used. It is assumed that the prosthesis was implanted in an adult subject under an excessive load. The obtained results were satisfied.
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    Anti Corrosion du Cuivre Par Revêtement Nickel - Phosphore
    (Conférence Nationale Sur la chimie des matériaux, (02-03 Juillet 2019), Faculté des sciences, Université M’Hamed Bougara Boumerdes, Algerie., 2019-07-02) LEKMINE Farid, Hachemi Bentemam, Abderrahmane Gana, ZIDANI Ibtissem
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    Applying of heat treatments to ameliorate the microstructural properties of welded pipeline steel
    (SÉMINAIRE INTERNATIONAL SUR L’INDUSTRIE ET LA TECHNOLOGIE, Algerian Journal of Engineering, Architecture and Urbanism, (12 - 13 Mars 2021), Algeria., 2021-03-13) Kelthoum Digheche, Farida khamouli ,LEKMINE Farid, Abdelouahed Chala
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    Artificial Neural Network Model Analysis of Tunable Circular Microstrip Patch Antenna
    (IEEE Xplore, 2019 International Conference on Advanced Systems and Emergent Technologies (IC_ASET), 2019) Bedra Sami
    In this paper, in order to evaluate the resonant frequency of tunable circular microstrip patch with a fast and accurate model, neural networks are introduced in the theoretical analysis. The obtained model is very suitable for the CAD of microstrip patch antennas. The output of the artificial neuronal network which is the resonant frequency is shown to be very close to the experimental results reported elsewhere. Finally, the influence of the air separation on the operating frequency of the circular disc is investigated.
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    CAD cavity model analysis of high Tc superconducting rectangular patch printed on anisotropic substrates
    (IEEE Xplore, 5th International Conference on Electrical Engineering-Boumerdes (ICEE-B), 2017) Bedra Sami
    This paper, present the resonant and the radiation characteristics of superconducting rectangular microstrip antenna printed on uniaxailly anisotropic substrate using an electromagnetic approach based on cavity model in conjunction with electromagnetic knowledge. The cavity model combined with London's equations and the Gorter-Casimir two-fluid model has been improved to investigate the resonant characteristics as well as the radiation patterns of high Tc superconducting rectangular microstrip patch in the case where the patch is printed on uniaxially anisotropic substrate materials. The most advantage of our extended model include low computational cost and mathematical simplify. The numerical simulation of this modeling shows excellent agreement with experimental results available in the literature. Finally, radiation patterns of superconducting rectangular patch on anisotropic substrate are also presented.
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    CFD Modeling of Thermophysical Properties Influence on The Heat Transfer in Metal Foam Heat Sinks
    (2019-05-09) Boulahrouz Salim , Chahaoui Oualid, Abdelmadjid CHEHHAT, Ghelani Laala, Abdelaziz Aboudi,Chermime Brahim
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    ComparativeStudyoftheThreeNitriding ProcessesonPartsCarbonSteel
    (2022-04-30) Ouafa Hamidane, BrahimChermime and MamounFellah
    The paper present a review of investigations on the tree types of nitriding, salt bath nitriding, gas nitriding and ionic nitriding on a stainless steel samples. In this study we will see the properties of each sample after each nitriding type, taking the principal parameters (the tomperature and holding time).
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    Effect of bath concentration on nucleation and growth of NI-Fe alloy thin films
    (1st National Conference On Material, Energy, environment, November 23-24-2022 Biskra, Algeria., 2022-11-23) Farid Lekmine , I. Zidani, Kelthoum Digheche
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    Effect of fiber packing on transverse shear modulus G23 of a unidirectional composite material Glass / Epoxy
    (2022) BREK Samir; Meddour Belkacem; BETTAYEB Mohammed
    Composite materials are widely used in the manufacture of mechanical and civil engineering structures. These materials are characterized by heterogeneity and anisotropy, so they present a great challenge of the prediction of the mechanical characteristics of the matrix/fiber mixture and especially in the transverse plane (2-3). The values of the transverse shear modulus G23 are always interesting researchers because of the diversity of results obtained by several approaches (analytical, numerical) and this modulus is used to study the mechanical behavior of composites in 3D. The main objective of this study is the predicting of G23 values within a unidirectional composite material with 44.3% fibers by volume, and to study the effect of the random position of the fibers on the mechanical behavior in shear for ten representative square elementary volumes (RVEs). Each RVE is composed of 16 cells (fiber with matrix or matrix without fiber) with a side of 48 μm. The composite material used in the numerical modeling corresponds to a unidirectional ply (UD) based on epoxy resin and long glass fiber (E) with a circular section. The developed numerical model to determine the transverse shear modulus G23 is carried out using finite element software CASTEM. Ten calculation programs using the GIBIANE language were developed. The obtained results were compared with those obtained by analytical and other available numerical models.
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    Effect of MoS2 content en Ni-Mos2 composites coatings and corrosion protection of steel (BS2)
    (First International Conference on Material Science and Applications, February 08-09, 2023, Khenchela University, Algeria., 2023-02-08) Gana Abderahmane, Lekmine Farid, Herzallah ouahiba, Hachemi Bentemam
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    Effect of Sodium dodecyl Sulfate on hardness and corrosion of Ni- MoS2 composite coating
    (1st International Seminar On chemical process and environment, 14-15 March,2023, Biskra University, Algeria., 2022-03-14) Gana Abderahmane, Lekmine Farid, Zidani Ibtissem, Herzallah ouahiba, Hachemi Bentemam
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    Effect of the three main directions of an external magnetic field on the free convection in Fe3O4- water nanofluid filled cubic enclosure
    (9th EUROPEAN CONFERENCE ON RENEWABLE ENERGY SYSTEMS, 2021-04-21) MAACHE Mouna BATTIRA,
    The present work studies numerically the influence of the three main directions of an external magnetic field on Fe3O4-water nanofluid free convective flow within a cubic enclosure subjected to horizontal temperature gradient. The MHD problem is mathematically modeled, and its dimensionless equations are established. The system of partial differential equations, governing the phenomenon, is resolved by a numerical approach based on the finite volume method using ANSYS Fluent. The impact of Rayleigh number (10^3≤Ra≤10^6 ), Hartmann number (0≤Ha≤20) and the three principal magnetic field directions on thermo-hydrodynamics behavior of nanofluid is also studied. This study is carried out for pure water (∅=0) and for a nanofluid with low solid volume fraction (∅=0.02). The correlations chosen for calculating thermal conductivity and dynamic viscosity are specifically developed for Fe3O4-water nanofluid from previous experimental studies. Simulation results reveal that the decrease of Nusselt number with increasing magnetic field strength becomes stronger with increasing the Ra number. Applying magnetic field horizontally i.e. parallel to the temperature gradient, decreases heat transfer greater than in the other two directions. In second position, the most significant reduction in convective heat transfer rate is recorded when magnetic field direction is vertical i.e. parallel to gravity.
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    EFFECTS OF MAGNETIC FIELD DIRECTION AND NANOPARTICLES CONCENTRATION ON FREE CONVECTION IN A VERTICAL CYLINDER
    (2019-12-17) MAACHE Mouna Battira, Samir Arrouf, Rachid Bessaih, Abdelmadjid Chehhat
    In this work, the effect of the magnetic field direction on laminar stationary convection heat transfer in a vertical cylinder filled with a CuO nanofluid is numerically studied. The magnetic field externally applied to the cylinder is once directed axially (Bz) and a second time directed radially (Br). The cylinder having an aspect ratio( H)⁄(R_0=3), is limited by two upper and lower walls at constant temperatures respectively cold Tc and hot Th and by an adiabatic sidewall. The equations of continuity, Navier Stocks and energy are non-dimensionalized and then discretized by the finite volume method. A computer program based on the SIMPLER algorithm is developed and compared with the numerical results found in the literature. The effects of the direction and intensity of the magnetic field on the dynamic field, on the thermal field and on the average Nusselt number are presented and discussed through the variation of the Hartmann number (Ha=0,5,10,15,20,30….60), as well as the effect of the nanoparticles volume fraction (∅=0,0.025,0.05,0.075,0.1) and this for three values of Rayleigh number ( Ra=10^3,5×10^3 and 10^4 ). The results found show that the average Nusselt number increases with the increase in the Rayleigh number but it decreases with the increase in the Hartmann number. Depending on the magnetic field direction and on the values of Hartmann and Rayleigh numbers, an increase in the volume fraction of the nanoparticles in the nanofluid may cause an enhancement or deterioration in the heat transfer performance in the nanofluid.
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    Etude des transferts de chaleur et de masse par condensation dans un tube vertical a paroi poreuse
    (2010-12-14) Merouani Lazhar
    L’étude présentée concerne la condensation en film lors de l’écoulement d’un mélange vapeur – gaz non condensables dans un tube vertical à paroi poreuse. Les équations de la couche limite et le modèle de Darcy-Brinkman-Forchheimer sont respectivement appliqués pour la couche poreuse et les phases gazeuse et liquide. Le couplage des équations des trois milieux est exprimé par la continuité des contraintes de cisaillement et des densités des flux thermique et massique aux interfaces liquide-gaz et liquide-milieu poreux. Les systèmes d’équations sont discrétisées par la méthode des différences finies. Les calculs effectués permettent de déterminer l’influence des propriétés du milieu poreux et du débit du mélange gazeux sur le comportement hydrodynamique du système.