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 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 The Role of Organizational Structure Flexibility in Facing Organizational Crises(la Revue Ivoirienne des Arts, des Sciences de l’Information et du Patrimoine, 2024) Nouiouat, Souad; Letaief, Abdelkrim; Bouazzouz, DjihadThis study investigates the role of organizational structure flexibility in anaging crises faced by institutions today. It emphasizes the significance of a flexible structure in adapting to rapid changes. Employing a descriptive analytical approach, the research collected data through questionnaires directed at employees from relevant institutions, resulting in 154 responses from 160 distributed surveys. Statistical tools, including the Pearson orrelation coefficient, were utilized to analyze the data and evaluate the relationship between organizational flexibility and crisis management effectiveness. Findings indicate that a flexible organizational structure accelerates decision-making, enhances internal communication, and strengthens institutions' adaptability to economic and technological crises. Additionally, the study highlights that such flexibility facilitates effective resource redistribution, minimizing the negative impact of crises on overall institutional performanceItem Asymptotic Issues for Fractional Laplacian on Long Cylinders(Birkhauser, 2025) Boudjeriou, Tahir; Roy, Prosenjitn this paper, we are concerned with the asymptotic behavior of weak solutions to certain elliptic and parabolic problems involving the fractional p-Laplacian in cylindrical domains that become unbounded in one direction. The nonlocal nature of the operator describing the equations creates several technical difficulties in treating problems of this type. The main results, obtained within a nonlocal abstract framework, extend and complement related properties established in the local settingItem The Impact of Electronic Management on Human Resource Development(2025) Nouiouat, Souad; Letaief, Abdelkrim; Bouazzouz, DjihadThis study aims to analyze the role of electronic management in the development of human resources within the Sonatrach research and development center located in Boumerdes, focusing on the challenges related to its implementation and the benefits it can bring. The research problem addresses questions regarding the effectiveness of electronic management in improving HR processes such as recruitment, training, and performance evaluation, as well as the level of employee satisfaction with these systems. A descriptive and analytical approach was adopted, with 120 questionnaires distributed to employees, of which 106 were returned. The results were analyzed using SPSS software. The findings show that electronic management significantly contributes to enhancing the efficiency of human resource management, particularly by streamlining processes, improving information accuracy, increasing employee satisfaction, and boosting performance. However, certain challenges were identified, particularly regarding technological infrastructure and cultural adaptation within organizations. The study recommends strengthening infrastructure and offering specialized training programs to facilitate adaptation to digital transformationItem Impact of calcination temperature, organic additive percentages, and testing temperature on the rheological behaviour of dried sewage sludge(DE GRUYTER, 2024) Bestani, Amar; Lekbir, Choukri; Benmounah, AbdelbakiThe main objective of the present work is to eval- uate the influence of calcination pretreatment (600–1,000°C), organic additive incorporation (4% methocel, 4% amijel, and 8% starch), and testing temperature (20–60°C) on the rheo- logical flow behaviour of dried sewage sludge and sewage sludge ashes. Besides, the dependency of sludge systems rheology on total solid content (4–15%) and methocel percentage (3–6%) was also evaluated. Furthermore, char- terization techniques such as thermal gravimetric ana- lysis-differential scanning calorimetry, X-ray fluorescence, X-ray diffraction, Brunauer–Emmett–Teller, and scanning electron microscopy were employed to investigate, respec- tively, the thermal decomposition, the chemical composition, the structural variations, the specific surface area, the surface morphology, and microstructure of sludges. The analysis of rheological characteristics according to best-fitting rheolo- gical models such as Herschel–Bulkley, Ostwald–de Waele, Cross, and Carreau models revealed that the yield stress (τ0) and infinite apparent viscosity (η∞) increase with an increase in TS or methocel percentage and decrease with increasing calcination or testing temperature. The strong impact of testing temperature concerning the reduction of the viscosity involves high activation energy (Ea). This last criterion was used to compare the inter-particle strength of sludge systems.Item Enhancing the transient performances and stability of three-tank liquid level using a modified pid controller(Revue roumaine des sciences techniques — Série électrotechnique et énergétique, 2025) Idir, Abdelhakim; Nesri, Mokhtar; Belhouchet, Khaled; Guedida, Sifelislam; Canale, LaurentManaging liquid levels in industrial tanks is crucial, especially for precise component mixing. Traditional PID controllers, though widely used, often exhibit slow settling times and excessive overshoot, which can affect system performance. This study proposes a fractionalized order PID (FrOPID) controller optimized using the Modified Artificial Hummingbird Algorithm (MAHA) to enhance stability and response in a three-tank system. The controller’s effectiveness is evaluated under varying valve coefficient (Kv) and tank cross-sectional area conditions. A comparative analysis with advanced metaheuristic-optimized PID controllers confirms the superiority of the MAHA/FrOPID in terms of accuracy, response speed, and robustness, making it a highly efficient solution for liquid level control.Item Deep learning and wbg devices combining to improve pv system efficiency: anfis-based mppt controller(2025) Bouchetob, Elaid; Nadji, BouchraWith the escalating demand for renewable energy sources, photovoltaic (PV) systems have emerged as a pivotal solution for sustainable power generation. The efficacy of these systems is paramount for their widespread implementation. This research article delves into the efficiency assessment of silicon carbide (SiC) components within a boost converter integrated into a PV system. Notably, the boost converter switch is under the intelligent control of an adaptive neuro-fuzzy inference system (ANFIS) based maximum power point tracking (MPPT) controller. This innovative approach leverages AI to optimize energy extraction from PV panels, thereby enhancing overall system efficiency. The cooperation of SiC components and AI-driven control presents a novel perspective on robust and efficient PV systems. To substantiate the research, data collected from the Sidi Bel-Abès PV central is utilized to train the ANFIS. The utilization of real-world data enhances the accuracy of the predictive model, thereby increasing its applicability to practical scenarios. Integrating AI technologies with PV systems marks a significant advancement toward intelligent and adaptive energy systems