Publications Internationales
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Item Enhancing resilience of repaired RC column using thin polypropylene fiber reinforced concrete jacketing(Techno-Press, 2025) Labdaoui, Rachid; Toukal, Abdennour; Kadri, MohammedThis study investigates the effectiveness of thin jacketing with polypropylene fiber-reinforced concrete for strengthening reinforced concrete (RC) columns. Full-scale specimens were retrofitted using thin jackets of polypropylene fiber- reinforced concrete, steel fiber-reinforced concrete, and plain concrete, then subjected to a constant vertical load combined with cyclic horizontal loading to simulate seismic conditions. Key performance metrics, including load-bearing capacity, ductility, energy dissipation, damage index, and cra ck propagation, were assessed and compared. The findings highlight the effectiveness of fiber-reinforced concrete thin jacketing in enhancing the seismic performance of RC columns. Notably, this method significantly improves load-bearing capacity, ductility, and energy dissipation while delaying crack formation and enhancing overall seismic resilience.Item Ethnobotanical knowledge and traditional uses of propolis among the Algerian population: a comparative and multivariate analysis(2025) Brahimi, Hibat-allah; Oulebsir-Mohandkaci, Hakima; Hendel, Noui; Sarri, MadaniBackground: Propolis is a natural resinous substance collected by honeybees from tree buds and plant exudates and is recognized for its beneficial biological properties. This study aims to provide a comparative overview of the various therapeutic, agri-food applications of propolis in Algeria, as well as the different forms and combinations with other natural products. ethods: This ethnobotanical study collected information on propolis use from 111 participants via semi-structured interviews. The data were an alysed by calculating various parameters, including usage value and the relative frequency of citations. We used Multiple Component Analysis (MCA) and Principal Component Analysis (PCA) to determine all propolis properties. Cronbach's alpha analysis was used to assess the homogeneity of our survey. We used Pearson's test (α = 0.05) to test the relationship between propolis production parameters. Results: The ethnobotanical survey revealed that (73%) of participants possessed detailed knowledge of propolis' properties. The reported therapeutic benefits included support for the digestive system (40.5%), immune system (72%), along with wound treatment (66.7%). The study also found that, in Algeria, propolis is combined with other natural products (55.9%), to increase its effectiveness. With data reliability and homogeneity, analysis is shown to be stable and consistent across all questionnaire criteria. In addition, the Pearson test determined a correlation between the color of propolis in Algeria and the type of the plants. Conclusions: This study expands our understanding of propolis and its various uses, emphasizing its potential for development into pharmaceutical, dermatological and agricultural products.Item Implementation of a real-time stereo vision algorithm on a cost-effective heterogeneous multicore platform(WILEY, 2022) Saidi, Taki Eddine; Khouas, Abdelhakim; Amira, AbbesStereo 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.Item 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, IdirThis 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%).Item Effects of water activity and temperature on the growth and ochratoxin A production of three Aspergillus species isolated from stored wheat in Algeria(Beijing Academy of Agriculture and Forestry Sciences, Institute of Plant and Environment Protection, 2025) Zebiri S.; Verheecke-Vaessen C.; Djemouai N.; Mokrane S.; Riba A.; Mathieu F.Wheat stored under uncontrolled conditions is susceptible to contamination by various ochratoxigenic Aspergillus species. Among the key environmental factors influencing the proliferation of these fungi are water activity (aw) and temperature. In this study, three ochratoxigenic Aspergillus isolates (Z1, Z11, and Z14) were isolated from stored wheat samples. The combined effects of different aw levels (0.85, 0.90, 0.95, and 0.99) and temperatures (25, 30, 35, 40, and 45°C) on lag phases and growth rates were systematically examined. The ITS nucleotide sequence analysis results identified isolate Z1 as Aspergillus westerdijkiae, while Z11 and Z14 were identified as A. alliaceus and A. carbonarius, respectively. The toxigenic potential of these fungal strains, assessed on the CYA medium, showed a high capacity for Ochratoxin A (OTA) production, with 3303.23 ng/g for A. westerdijkiae, 950.23 ng/g for A. alliaceus and 801.28 ng/g for A. carbonarius produced at 25°C. The shortest lag times prior to growth (< 24 h) were observed at 0.95 aw/25°C for A. westerdijkiae (2.19 h), at 0.99 aw/35°C for A. alliaceus (0.75 h) and at 0.99 aw/30°C for A. carbonarius (1.03 h). The maximum growth rates were recorded as follows: A. westerdijkiae at 9.3 mm/day (25°C/0.99 aw), A. carbonarius at 11.1 mm/day, and A. alliaceus at 16.5 mm/day (both at 30°C/99 aw). In almost all compared pairs, the effects of varying aw and temperatures on lag time before and after development rates were significantly different. These findings provide valuable insights for designing effective wheat storage strategies and ultimately improving food safety in AlgeriaItem Bacterial Population Kinetics and Physicochemical Profiles in Fermented Goat Milks: Roles of Streptococcus thermophiles ATCC19258 and Lactobacillus bulgaricus ATCC11842(National Nutrition and Food Technology Research Institute, 2025) Tayeb, Silarbi; Morsli, Amirouche; Saadia, Laabas; Mohamed, Chahbar; Khaled, Hamden; ben Salah-Abbes, JalilaBackground and Objective: The fermentation of Algerian goat milk, a process for the production of valuable dairy products, relies on the synergistic activity of Streptococcus (S.) thermophilus and Lactobacillus (L.) bulgaricus. However, a significant knowledge gap is seen regarding the precise dynamics of these starter cultures within the unique matrix of Algerian goat milks. Specifically, the intricate relationships between their growth patterns and the resulting physicochemical changes, which regulate the distinct biochemical characteristics of fermented products, are poorly understood. So, this study addressed this problem by studying specific contributions of S. thermophilus and L. bulgaricus to goat milk fermentation. Material and Methods: Goat milk was fermented by starter cultures of S. thermophilus and L. bulgaricus (8 h). Bacterial growth and physicochemical parameters, including pH, titratable acidity, viscosity and syneresis, were assessed. Mixed-effects models were used for statistical analysis to assess the relationship between physicochemical changes and bacterial growth. Results and Conclusion: The results showed a strong relationship between L. bulgaricus and the control of acidification, viscosity and syneresis (r = 0.979 for titratable acidity, p < 0.0001). S. thermophilus contributed significantly, particularly to the increases in viscosity (r = 0.773, p < 0.01). The two species significantly decreased the pH, with L. bulgaricus having twice the acidifying effects. By the end of the fermentation process, pH reached 4.12 ±0.20, titratable acidity increased to 84.75 ±2.19 °D and viscosity increased to 6425.00 mPa.s ±638.64. The final bacterial counts of S. thermophilus and L. bulgaricus were 519.00 ±115.29×10⁷ and 65.54±6.89×10⁷ CFU.ml-1, respect-ively. In addition to providing a robust statistical framework for process control and quality assurance in fermented milk manufacture, this study highlighted the critical role of L. bulgaricus in regulating structural and sensory qualities of fermented goat milks. Results can be used to optimize fermentation processes for goat milk by strategically manipulating the ratio of L. bulgaricus to S. thermophilus. The strong correlation between L. bulgaricus and acidification, viscosity and syneresis (r = 0.979 for titratable acidity, p<0.0001) provides a clear target for controlling key product attributesItem 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, NicuThis 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.Item 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, KhellafThe 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 compoundsItem 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, FerroudjaThis 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 (FeO, ZnO, CuO, CaO) 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 optoelectronicsItem 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.