This study aimed to characterize the vibrational behavior of damaged Carbon Fiber-Reinforced Polymer (CFRP) plates repaired with adhesively bonded composite patches. The primary goal was to evaluate the repair’s effectiveness in restoring dynamic properties, with a specific focus on damping performance and the influence of patch characteristics. The research combined experimental and numerical methods. First, the mechanical properties of the materials were determined through tensile and three-point bending tests. Experimental modal analysis was then conducted using an impact hammer and accelerometers to obtain Frequency Response Functions (FRFs) for intact, damaged, and repaired plates under free-free and clamped-free boundary conditions. These experimental results were used to validate a finite element model developed in ABAQUS to simulate the dynamic response and analyze stress distributions. The results demonstrated that the patch repair significantly enhances structural damping, with a measured damping coefficient of approximately 0.32. The natural frequencies decreased for damaged plates but were partially restored after repair. The CFRP patch with a (45/-45) ply orientation was found to be the most effective configuration, exhibiting superior vibration damping and the lowest stress concentrations in the adhesive layer—20
Dye-laden wastewater presents a critical global environmental issue, requiring sustainable and bio-based treatment strategies for the effective removal of hazardous pollutants. The adsorption of methylene blue (MB), a cationic dye, using raw cupule scale (CR) as a natural bioadsorbent was investigated in this study. Additionally, untreated cupule scales were selected for further evaluation of the cationic dye adsorption process. The physicochemical characterization of the adsorbents was carried out using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and the determination of the point of zero charge (pHPZC) (7.2). The influence of key operational parameters, including contact time, adsorbent dosage, solution pH, and initial dye concentration, was systematically investigated and optimized using the Box-Behnken Design (BBD). The equilibrium data showed an excellent fit to the Langmuir isotherm model with correlation coefficient R2 = 0.99 at 20 degrees C while kinetic analysis indicated that the pseudo-second-order model best described the adsorption behavior, suggesting a chemisorption-controlled mechanism with a maximum adsorption capacity of 102.315 mg/g. Among the advanced isotherm models evaluated, the double-energy monolayer model provided the most accurate description of MB adsorption on CRs (R2 greater than 0.9981, MRSE little than 0.015), revealing a multimolecular adsorption mechanism with a primary receptor site density (Nm1) reaching up to 318.2 mg/g. Thermodynamic analysis confirmed that the adsorption process is exothermic and spontaneous, with adsorption efficiency decreasing at higher temperatures. These findings underscore the potential of CR as an effective, natural, and cost-efficient adsorbent for mitigating MB contamination in aqueous systems.
This article offers an immanent analysis of the novel Des rêves et des assassins by the Algerian author Malika Mokeddem, focusing on the trajectories of two female characters, Selma and Kenza, in order to examine how exile unfolds through successive and complementary stages. The study highlights an inner exile, characterized by emotional wounds, family tensions, and psychological fractures, which generates disorientation and revolt, and leads to a geographic exile. This spatial mobility, chosen as a refuge and a space for reconstruction, allows Kenza to regain a form of long-restricted freedom. The findings reveal the complexity of the processes of release depicted in the novel and demonstrate how the different forms of exile transform suffering into a source of resilience. The immanent approach makes it possible to identify these textual dynamics while emphasizing the necessity of integrating certain theoretical contributions, such as those of Bolzman, Nicollet, Kristeva, and Douville, to consolidate the conceptual framework of the analysis.
Drought is an escalating hazard in arid and semi‑arid regions with significant implications for agriculture, ecosystems, and water resources. This study presents a 2003–2023 integrated assessment of meteorological and vegetation-based drought across northwest Algeria, using the Climate Hazards group Infrared Precipitation with Stations (CHIRPS) dataset and Moderate Resolution Imaging Spectroradiometer (MODIS) remotely‑sensed products. Meteorological drought was quantified with the Standardized Precipitation Index (SPI) approximated using standardized precipitation anomalies, at 3‑, 6‑, and 12‑month timescales, whereas vegetation and thermal stress were assessed with MODIS‑derived Vegetation Condition Index (VCI), Temperature Condition Index (TCI), and Vegetation Health Index (VHI). Temporal trends were evaluated using the Mann–Kendall test and Sen’s slope estimator, and relationships between precipitation and vegetation were examined with Pearson correlation. We identified recurrent drought episodes in 2007–2009, 2011–2012, and a pronounced dry phase from 2020–2023. Mann–Kendall results indicated widespread drying across all SPI timescales, with 56
Depuis plusieurs décennies, l’enseignement du français langue étrangère (FLE) repose sur des règles grammaticales considérées comme des repères universels et intangibles. Cependant, dans le contexte maghrébin et plus particulièrement algérien, ces règles se révèlent souvent inadaptées aux réalités cognitives, linguistiques et culturelles des apprenants. Eldjoubaria, conçue à partir d’une longue expérience de terrain, propose une relecture critique et constructive de huit règles fondamentales de la grammaire française afin de les rendre plus accessibles, logiques et cohérentes pour l’enseignement du FLE. S’inscrivant dans une perspective fonctionnelle et humaniste, cette approche privilégie la compréhension du sens et l’usage communicatif de la langue plutôt que la mémorisation mécanique. L’article présente les fondements théoriques d’Eldjoubaria, expose les huit règles révisées selon une démarche de simplification et de clarification, et discute leurs implications didactiques pour la formation des enseignants et la conception des manuels. En redéfinissant la place de notions clés telles que le verbe, le sujet, le thème ou le passé composé, cette approche ouvre la voie à une pédagogie linguistique plus cohérente, adaptée et contextualisée.
