Publications Internationales

Permanent URI for this collectionhttps://dspace.univ-boumerdes.dz/handle/123456789/13

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    Implementation of a real-time stereo vision algorithm on a cost-effective heterogeneous multicore platform
    (WILEY, 2022) Saidi, Taki Eddine; Khouas, Abdelhakim; Amira, Abbes
    Stereo vision is a major computer vision technique commonly used for robotics appli- cations. Existing software implementations of this technique on general-purpose pro- cessors offer low time-to-market compared to other platforms. However, such imple- mentations can hardly achieve real-time and their cost is usually relatively high. These issues can be solved by embedded multicore platforms. In this article, we present a low-cost, improved software implementation of a stereo matching algorithm in the cor- relation stage that combines a sparse rank transform with a combination of sum of absolute differences 1-D and 2-D box filtering algorithms. A circular buffer scheme is used to optimize memory usage during the rank computation stage. The system runs on a heterogeneous multicore platform (ODROID XU4). Through the extensive use of single instruction multiple data Neon intrinsics, the system can process images with a size of 320 × 240 pixels and a disparity range of 20 pixels at a rate of 111 frames per second. The proposed system can be used in mobile robot platforms that require low power consumption while delivering real-time performance.
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    Topological optimization of dimple distribution for enhanced performance in hydrodynamic porous self-lubricating journal bearings with sealed ends
    (Sage, 2025) Ifrah, Walid; Manser, Belkacem; Chellil, Ahmed; Ragueb, Haroun; Mechakra, Hamza; Khelladi, Sofiane; Belaidi, Idir
    This study numerically investigates the impact of optimal textures location on the performance of hydrodynamic porous self-lubricating journal bearings with sealed ends, subjected to a stationary load. The analysis employs a modified Reynolds equation coupled with Darcy’s law to model fluid flow in both the lubricating film and the porous matrix, considering the hydrodynamic self-lubrication problem. The governing nonlinear PDE systems were solved numerically using the finite difference method, combined with Reynolds boundary conditions and continuity conditions for velocity and pressure at the film-bush interface. A Binary Genetic Algorithm (BGA) is employed to optimize the topological distribution of square dimples in the textured porous layer to enhance bearing performance. The study investigates the influence of key parameters, including applied load, rotational speed, permeability, and texture depth, on bearing characteristics such as minimum film thickness and friction coefficient. Results show good agreement with benchmark data and indicate a positive enhancement in porous bearing performance. In addition, findings demonstrate that increasing the permeability of the porous structure reduces bearing performance (up to 25% in minimum film thickness and 8% in friction coefficient). However, the application of the optimization technique identified an optimal arrangement of textures that compensates for these performance losses, even under severe working conditions. Texturing the outlet region of the contact (beyond 180°) at the cavitation zone causes a micro-step bearing mechanism, generating localized pressure recovery within the textured area, significantly enhancing the minimum film thickness (up to 12%), reducing friction (up to 23%), and minimizing cavitation (up to 24%).
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    Novel adaptive power control based 3L-VSI for variable-speed wind turbine: HIL-experimental investigation
    (Elsevier, 2025) Amrane, Fayssal; Gherouat, Oussama; Itouchene, Hichem; Ben Oualid Medani , Khaled; Chaiba, Azeddine; Benbouhenn, Habib; Bizon, Nicu
    This study introduces an advanced control strategy for doubly fed induction generators (DFIGs) in variable-speed wind energy conversion systems (WECSs), combining model reference adaptive control (MRAC) with input-output linearizing and decoupling control (I/OLDC). The system employs a three-phase, three-level voltage source inverter (3L-VSI) to drive the DFIG, with a focus on regulating active and reactive power through precise rotor current control. The core algorithm leverages feedback linearization to decouple power dynamics, while MRAC enhances tracking accuracy by continuously aligning measured stator power values with their references. Simulation and Hardware-in-the-Loop (HIL) tests using a dSPACE1104 platform and ControlDesk demonstrate superior performance compared with conventional PI control, including rise time < 0.2 ms (MRAC) versus ≈ 4.5 ms (PI), steady-state power errors < 2 % (MRAC) versus ≈ 10 % (PI), active/reactive power decoupling within overshoot of 1.5 % (MRAC) versus ≈ 15 % (PI), stator-current THD of 0.5 % (MRAC) versus ≈ 7 % (PI), and the robustness and reliability of the DFIG-wind system under parameter change and grid-fault of ≈ 50 % (MRAC) versus 20 % (PI). These results confirm that the proposed MRAC–I/OLDC method ensures robust, fast, and accurate power control, maintains grid compliance, and optimizes energy extraction under turbulent wind and grid conditions.
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    The first investigation of the chemical composition antioxidant and antibacterial activities of the aerial parts aqueous methanolic extract of the Algerian endemic plant Psychine stylosa desf
    (Taylor and Francis, 2025) Tarik, Turqui; Ghania, Benaiche; Hadi, Debih; Imen, Benkouider; Rebbas, Khellaf
    The phytochemical profile of the aqueous methanolic extract from the aerial parts of Psychin stylosa Desf., an Algerian endemic species belonging to the Brassicaceae family and previously unstudied, was analysed using the HPLC-MS/MS technique, allowing for the identification of 65 compounds from diverse chemical classes, including phenolic compounds, flavonoids, sugars, alkaloids, sulphur compounds, peptides, terpenoids, and steroids, as well as 13 unidentified compounds. The extract showed a high total polyphenol content of 64.39 ± 1.63 mg GAE/g extract and a flavonoid content of 20.39 ± 0.53 mg QE/g extract, indicating its richness in bioactive phenolic constituents. It also exhibited strong antioxidant activity, with an IC50 value of 9.82 ± 1.70 µg/mL in the DPPH assay, while no antibacterial effect was observed against the tested bacterial strains. This study represents the first report combining phytochemical characterisation and biological evaluation of this plant species, highlighting its potential as a natural source of antioxidant compounds
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    Eco-friendly Ca/α-Fe2O3/ZnO/CuO nanocomposite: Green synthesis, characterization, and high-efficiency heavy metal removal from contaminated sludge
    (John Wiley and Sons Inc, 2025) Saoud, Abdesselam; Bouafia, Abderrhmane; Meneceur, Souhaila; Younsi, Ferroudja
    This study explores the green synthesis of Ca/α-Fe2O3/ZnO/CuO nanocomposite using Mentha pulegium L. leaf extract as a bioreducing and stabilizing agent for eco-friendly remediation. XRD confirmed a multiphase crystalline structure—cubic Ca, rhombohedral α-Fe2O3, hexagonal ZnO, and monoclinic CuO—with an average crystallite size of 24.42 ± 3.07 nm. SEM revealed ~50 nm agglomerated nanoparticles with rough surfaces, enhancing catalytic reactivity. FTIR identified metal–oxygen bonds (FeO, ZnO, CuO, CaO) and plant-derived functional groups, confirming stabilization. UV–Vis showed strong absorption at 275 nm with direct (3.07 eV) and indirect (1.70 eV) bandgaps, suitable for UV/visible-light applications, and the low Urbach energy (0.211 eV) further reflected the material's high crystallinity. TGA-DSC demonstrated 49% residual mass at 1200°C, reflecting strong thermal stability. A zeta potential of −29.06 mV ensured colloidal stability. The nanocomposite efficiently removed heavy metals from petroleum sludge, achieving 84.1% (Pb), 74.6% (Zn), 72.3% (Se), and 73.7% (Cr), while arsenic removal was relatively lower at 24.9%, highlighting current adsorption challenges. Adsorption involved diffusion and chemical fixation, underscoring potential in remediation, photocatalysis, and optoelectronics
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    Multiple-relaxation-time lattice Boltzmann analysis of the flow and temperature structures in a ventilated cavity: impact of inlet fresh fluid jet
    (Kutateladze Institute of Thermophysics SB RAS, 2025) Abdellouche Y.; Belmedani M.; Himrane N.; Ameziani D.E.
    This paper presents a summary of a numerical study of mixed convection in a two-dimensional ventilated square cavity; it discusses the impact of the fresh inlet fluid jet on the flow and temperature structures. A saturated porous partition of thickness Ep = H/5 is positioned at the center of the cavity bottom with a height Hp between H/5 and H, while the vertical walls are kept adiabatic and impervious, the bottom horizontal wall is subject to a vertical thermal gradient. The momentum conservation equation uses the Darcy model with an energy equation, including the Brinkman extension, the multi-relaxation time collision factor based lattice Boltzmann method is used to solve the set of coupled equations. The numerical results present and discuss flow patterns and thermal field structures, reveal important physical quantities, such as the local and mean Nusselt value on the bottom wall. The parametric study presents the effects of Reynolds and Rayleigh numbers with respect to a given Darcy number and porous wall height. For a high Darcy number, the porous medium increases the surface of action of the cold fluid. In addition, by increasing the height of the porous wall, the thermal draft (Ra) has little influence on the Nusselt values.
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    The Role of Building a Work Environment in Improving Employee Performance: Challenges and Solutions
    (2025) Nouiouat, Souad; Letaief, Abdelkrim; Bouazzouz, Djihad
    This study explores the significant impact of the work environment on employee performance at Sonatrach, Algeria's national hydrocarbons company. It suggests that various factors, such as the physical workspace, interpersonal relationships among colleagues, and the level of administrative support, play a vital role in shaping productivity and employee satisfaction. Utilizing a methodology that involved distri buting 60 questionnaires to employees, with 55 responses validated for statistical analysis, the study aimed to assess the correlation between work environment components and performance. The results reveal a positive relationship between a conducive physical environment, effective management practices, and strong professional relationships, all of which contribute to enhanced employee performance. These findings underscore the necessity for organizations to invest in improving workplace conditions as a long-term strategic approach to enhance productivity and employee satisfaction.
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    3D numerical analysis of MHD‐assisted forced convection and entropy generation in a porous heated tube using ternary nano‐fluids
    (Springer, 2025) Zeroual, Hamza; Benkhedda, Mohammed; Boufendi, Toufik; Tayebi, Tahar
    This study presents a numerical investigation of magnetohydrodynamic forced convection and entropy generation in a uniformly heated horizontal tube flled with porous media, using binary (Al2O3–TiO2/Water-EG) and ternary (Al2O3–TiO2–CNT/ Water-EG) hybrid nano-fuids. The fow and thermal felds are modeled using the fnite volume method with single-phase and thermal-equilibrium assumptions. The analysis is conducted for a Reynolds number of 750, nanoparticle volume concentration of 6%, Darcy numbers ranging from 10⁻ 4 to 10⁻ , and Hartmann numbers between 10 and 40, under two magnetic feld orientations (0° and 90°). The results demonstrate that reducing the Darcy number signifcantly enhances heat transfer, with the binary hybrid nano-fuid achieving up to a 105.36% improvement. Additionally, applying the magnetic feld parallel to the fow (0°) leads to further enhancement, particularly for the ternary hybrid nano-fuid. In contrast, when the magnetic feld is perpendicular (90°), its infuence on thermal performance is negligible. This study highlights the synergistic efects of nanoparticle composition, magnetic feld orientation, and porous media structure, ofering new insights into optimizing nano-fuid-based thermal systems for enhanced energy efciency.
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    Olive Leaf Extract as a Potential Anti-Corrosion of Copper-Nickel in Natural Seawater
    (Springer Science and Business Media, 2025) Bourouis, Douniazed; Ghemmit-Doulache, Naima; Bounechache, Foudil; Trari, Mohamed
    This study investigates the phenolic composition of olive leaves from Skikda region (Northern Algeria), focusing on their therapeutic potential for diabetes and hypertension due to their high content of phenols, particularly oleuropein. The leaves were dried, micronized and characterized by FT-IR spectroscopy. The obtained powder was subjected to various extraction techniques, including microwave, Soxhlet, Ultrasound-Assisted Extraction (USAE) and traditional maceration. The extracted compounds were analyzed by gas chromatography-mass spectrometry (GC/MS) and Ultra-High Performance Liquid Chromatography (UHPLC) coupled with electrospray ionization-quadrature-time-of-flight mass spectrometry (ESI-Q-TOF-MS). The presence of olivetol and two oleuropein isomers, highlighted the rich phenolic profile of the leaves. The study also examines the efficacy of olive leaf extract, particularly from traditional maceration, to prevent corrosion in the Cu-Ni alloy (90/10) seawater, one of the most corrosive environments. The results showed a high inhibitory efficiencies of 96.8% for the highest concentration (S1) by Tafel and 93% for the lower concentration (S3) by Electrochemical Impedence Spectroscopy (EIS). Scanning electron microscopy (SEM) and energy dispersive X-ray (EDS) analyses confirmed that the surface of the treated alloy remains free of corrosion, unlike the untreated alloy, which shows significant deterioration with a black corrosion layer attributed to the cuprite Cu2O. The study focuses on the identification of olivetol in olive leaf extract and its remarkable properties, for potential and preventive applications against corrosion
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    Enhancing aircraft safety: Automated three-dimensional defect detection, localization and sizing in non-destructive testing
    (Elsevier, 2025) Gouicem, Ali Mohamed Tahar; Ouahabi, Abdeldjalil; Yahi, Mostepha; Jacques, Sébastien
    In most cases, non-destructive testing (NDT) techniques typically rely solely on two-dimensional image data for defect detection, particularly in CT imaging. This limitation hindered the ability to accurately reconstruct the exact three-dimensional form of defects. In this study, we propose solutions for three-dimensional image reconstruction, which is crucial in industrial non-destructive testing applications and in the aircraft industry. We introduce a new, fully automated method for detecting, locating, and sizing defects in the context of non-contact quality control in industry, specifically focusing on aircraft-type equipment. Our method was applied to a confidential database containing over 120,000 images from Tassili Work Airlines Company. This database was curated and labeled by senior experts in the field of diagnostics and non-destructive testing, and we compare our results with theirs. Our combined approach, utilizing expectation maximization and fuzzy inference penalty, proves to be effective in addressing the challenging inverse problem of three-dimensional computed tomography defect detection, localization, and dimensioning