This study addresses the critical challenge of reducing operating temperature in photovoltaic (PV) systems, as excessive heat generation impairs their electrical efficiency and power output. A novel mini-channel heat sink with a folded U-shaped fin design is introduced to enhance heat dissipation, offering a scalable solution for optimizing PV performance. The design increases the heat transfer area while reducing airflow velocity by narrowing the channels, and optimizing thermal management. Experiments were conducted indoors under controlled conditions, with inlet air velocity of 0.3, 0.6, 0.8, and 1 m/s and solar irradiances of 500 and 1000 W/m2. The outcomes showed that the mini-channel heat sink effectively reduced the average cell temperature by 57.44 %. This significant thermal regulation increased electrical efficiency by 26.6 %, resulting in a 37.55 % increment in power output. The experimental findings were further compared to numerical simulations achieving an acceptable range of variation and ensuring the reliability of the results with an average heat transfer coefficient error percentage below 5 %. The originality of this work lies then in its unique U-shaped mini-channel design, which mitigates thermal stress and optimizes energy output. It provides a promising approach to advancing PV cooling technologies and a scalable solution for improving solar energy efficiency.
This article presents a linguistic analysis of language dysfluencies produced in exolingual situations. The study is based on a collection of real interactions recorded between Algerian doctors in a university hospital in the country. Following a corpus linguistics approach, the oral data were transcribed according to conventions adapted to spoken language. The description will focus on communication strategies that help manage the production difficulties encountered. The objective of the article is to identify the most frequent markers of disfluencies in the corpus, such as lexical repetitions, interrupted sentences, and terminological confusions. Additionally, it aims to explore whether there is a functional link between these disfluencies and language cooperation strategies, in order to ensure the dynamic of exolingual communication in a linguistic and professional context.
This study presents the development and validation of a hybrid cutting force prediction model for ball end milling of aluminum 7075-T6 alloy. The model combines a mechanistic approach with a specific cutting force coefficient (Ks=850 N/mm²) sourced from experimental literature. Cutting forces in the x, y, and z directions are predicted by integrating differential force components with tool geometry and machining parameters. Experimental validation was performed under dry conditions at a spindle speed of 15,000 rpm. In the x-direction, the simulated force was 162.4 N versus an experimental force of 215.4 N; in the y and z-directions, predicted values (65.2 N and 25.3 N) closely matched experimental forces (74.3 N and 28.2 N), respectively. The corresponding mean absolute errors were 18.2% (x), 4.5% (y), and 3.3% (z). The higher error in the x direction highlights limitations in modeling tangential force dynamics, while the y and z predictions align closely with experimental data. Leveraging the experimentally derived Ks, the proposed model offers a practical tool for optimizing machining processes in the aerospace sector, with potential for further refinement in tangential force modeling.
This study set out to examine the thermo-mechanical behavior of gypsum-protected steel columns (GPSC) exposed to fire, including the cooling phase, through numerical analyses with the aim of better understanding the effect of protection materials and identifying the possibility of delayed failure of GPSC during this critical period. A parametric study has been performed with the SAFIR program using a sequentially decoupled thermal structural analysis. The examined factors are the shape of the columns, the fire intensity, and the thickness of the protection. Gypsum serves as insulation, providing passive protection to prevent the degradation of steel mechanical properties and to mitigate and delay the collapse of steel columns during fire exposure. Different thicknesses of gypsum were considered (1 mm, 3 mm, and 5 mm) in order to analyze the effect of the rate of heat storage on the delayed collapse during and after fire exposure. The simulations were performed considering ISO fire and parametric temperature–time curves, which include a cooling regime that is linear. The findings show that the failure of the GPSC over the period of cooling is a possible event where the protection acts as a cooling retarder, which leads to a delayed collapse. Columns with massive sections and thick layers of protection are the most susceptible to delayed failure. Overall, this paper provides a real assessment of the load capacity in a natural fire situation, and the results highlight the possibility of delayed collapse of GPSC.
Thermal runaway of a chemical process is a dangerous phenomenon that threatens human life, equipment, installations, and the environment. The aim of our work is to propose a methodology for analyzing and quantitatively assessing the risk of thermal runaway in a polymerization reactor. Firstly, HAZard and OPerability analysis(HAZOP)is used to determine the most critical deviations likely to occur in the polymerization reactor under study and leading to the thermal runaway phenomenon. The various accident sequences are determined and evaluated using event tree analysis (ETA). The causes of the failure of safety barriers implemented in the reactor to prevent the runaway phenomenon are determined using fault tree analysis (FTA). Finally, an economic analysis is carried out to show the economic impact of safety failure barriers on the company. Application resultsof the proposed methodology show its relevance as a decision-making tool for good industrial risk management. The novelty of this hybrid approach lies in its systematic workflow. Qualitative identification (HAZOP) directly informs quantitative frequency estimation (ETA), which in turn relies on detailed reliability analysis (FTA) to assess safety barrier performance. This integrated methodology not only provides a quantitative risk frequency but also identifies the most critical safety barriers and offers an economic rationale for investment decisions through cost-benefit analysis (CBA), thereby bridging the gap between technical risk assessment and managerial decision-making
Cet article interroge les pratiques langagières en ligne des étudiants de français de l'université de Batna (Algérie) et leur fonction dans la construction identitaire. Dans un contexte de mutations sociolinguistiques rapides, exacerbées par les interactions numériques, l'écrit numérique devient un observatoire privilégié pour saisir les dynamiques du "parler jeune" local. Loin d'être de simples écarts à la norme ou des jeux linguistiques éphémères, nous posons l'hypothèse que ces usages créatifs constituent des stratégies performatives délibérées. La problématique centrale est donc de déterminer comment, et avec quels moyens linguistiques, les étudiants façonnent, négocient et affirment une identité batnéenne spécifique dans l'espace numérique. L'étude mobilise un double cadre. Sur le plan théorique, elle s'inscrit dans la sociolinguistique urbaine (Bulot, 2004 ; Calvet, 1993) et l'analyse du discours numérique (Paveau, 2017), en considérant le langage comme une action (performative) et un marqueur identitaire. Sur le plan méthodologique, une analyse de discours qualitative a été menée sur un corpus de conversations authentiques (groupe de Messenger). L'analyse se concentre sur les phénomènes d'alternance codique (arabe dialectal, français, anglais), l'inventivité lexicale (ex: "bagaindi") et les débats métalinguistiques. Les résultats démontrent que la créativité langagière n'est pas anarchique mais suit une logique précise. Elle fonctionne comme un mécanisme en trois temps : elle puise dans les ressources d'un sociolecte jeune plurilingue, elle s'adapte aux contraintes et potentialités de l'écrit numérique (concision, expressivité), et elle vise la performance identitaire. L'étude révèle notamment que l'affirmation de l'identité locale passe par des stratégies de distinction (validation de l'authenticité, comme en témoignent les débats sur la "vraie" signification du terme "bagaindi") tout en s'articulant à une identité jeune globale et connectée, illustrant une identité hybride. En définitive, le "parler jeune" batnéen en ligne n'est pas seulement un reflet, mais un puissant outil de négociation et d'affirmation de soi, façonnant activement ce que signifie être jeune et batnéen aujourd'hui.
Introduction: Obesity is a metabolic disease characterized by abnormal fat accumulation. Physical inactivity can contribute to this accumulation of fat, which reduces cardiorespiratory capacity in obese women. The excess weight can impair both cardiometabolic and mechanical functions. The perimenopausal phase is marked by changes that affect women's body composition. Our aim is to identify the effects of body composition on cardiorespiratory capacities of perimenopausal women living with obesity. Methods: The present study was concerned with 51 women obese patients (BMI ≥ 30 Kg/m2). Body composition analysis was carried out by Bioelectric Impedance Analyser (BIA) which identified total body fat mass (FM) and the lean mass (LM) in Kg and as a percentage. Cardiorespiratory capacities (VO2 max), heart rate max (HRmax) and metabolic equivalent of task (MET) were assessed using an ergocycle. The correlations between body composition and cardiorespiratory capacities were calculated. Results: Average age of the obese women of the present study was 41.1 ± 12 years with average BMI of 36.9 ± 5.4 Kg.m-2. Average body weight was 93.43 ± 14.9 kg with an average Fat Mass (FM) of 41.3 ± 10 kg were observed. Average Heart Rate max (HRmax) of 152 ± 17 bmp with an average VO2 max was 16.5 ± 2.08 ml. Kg -1.min-1 Were observed for the present study. Negative and statistically significant correlations were observed between VO2 max and BMI (r = - 0.49, p ≤ 0.02), between VO2 max and FM % (r = - 0.61, p ≤ 0.01). Similarly, HRmax was inversely correlated (r = - 0.71, p ≤ 0.001 with age). Conclusion: The accumulation of fatty tissue in our series seems to negatively influence cardiorespiratory capacities in perimenopausal women with obesity. Fat mass as a percentage provides better information on the evolution of VO2 max. In addition to age, this category of obese seems to present a limitation in effort that must be taken when prescribing an appropriate physical activity.
Introduction/purpose: Algerian natural zeolite (denoted NZ) was modified using hydrochloric acid (HZ) and sodium hydroxide solution (NaZ). This study investigated the impact of acid and alkaline modifications on the adsorption of two cationic textile dyes (BR46 and BY13) from aqueous solutions. Methods: The XRF analysis confirmed that SiO2 is the predominant mineral in all three zeolites. The XRD results revealed that NZ is primarily composed of mordenite, with chabazite and minor quartz content. The MEB-EDX analysis showed slight variations in the Si and Al content for HZ and NaZ, without significantly altering the zeolite’s structure.. The effects of initial dye concentration, contact time and pH were examined in a batch system.
Results: The adsorption on NZ, NaZ and HZ increased with longer contact times, higher initial dye concentrations, and elevated temperatures. Equilibrium was rapidly attained best described using the pseudo-second order kinetic model. Both the Langmuir and the Freundlich isotherm models fit for the adsorption data. Conclusion: The highest dye removal efficiency was observed for NaZ, with 97.62% for BR46 and 98.97% for BY13. The lowest removal rates occurred at pH= 8 for HZ and pH=10 for NZ and NaZ. Adsorption was spontaneous and endothermic.
Ensuring the safety and health of assembly line workers is critical to increasing productivity and preventing accidents. This research presents a real-time monitoring system that combines computer vision (AI), wearable Internet of Things (IoT) devices, and cloud-based technologies to detect worker fatigue and health risks. The system calculates eye aspect ratio (EAR) and mouth aspect ratio (MAR) to identify fatigue symptoms such as eye closure and yawning, while wearable IoT devices monitor physiological parameters such as heart rate (HR) and blood oxygen saturation (SpO₂) to detect potential health issues. Alerts are automatically triggered based on pre-defined thresholds, allowing for immediate intervention. All data is processed in real-time with input from wearables and computer vision, and transmitted to a cloud platform for analysis, reporting and storage. This integration of AI-powered computer vision, wearable IoT and cloud connectivity ensures continuous monitoring and provides actionable insights to supervisors, improving workplace safety and operational efficiency. The results of the study demonstrate the effectiveness of this innovative system in identifying fatigue and health issues, reducing accidents and promoting a safer working environment. By using the latest technology, the proposed solution addresses the urgent need for advanced safety measures in demanding work environments.
Introduction purpose: As population growth and industrial expansion continue, surface freshwater reservoirs such as dams have become increasingly vital due to their accessibility and ease of treatment. However, the quality of these water sources has significantly deteriorated, primarily due to the discharge of domestic and industrial wastewater. The proliferation of extensive algal blooms has led to significant challenges in maintaining drinking water quality and raised concerns about public health. This study investigates the impact of various water sources on the physicochemical quality of an Algerian dam over four seasons (December 2020 – October 2021) and explores the factors influencing the occurrence of cyanobacterial blooms to better understand and manage this excessive growth.
Methods: Physicochemical properties and algal composition of the dam water were analyzed monthly to determine nutrient sources and environmental factors affecting cyanobacterial proliferation. Results: The analysis revealed that the Timgad stream and Reboua valley are notable sources of nutrient enrichment. Elevated temperatures and high nutrient loads, particularly total phosphorus (TP), in Timgad dam water facilitate the proliferation of blue-green algae. Additionally, limited nitrogen content favors the dominance of nitrogen-fixing cyanobacteria such as Aphanizomenon and Oscillatoria. The study also highlights that the low flow rate and high nutrient load of the Timgad stream create favorable conditions for cyanobacterial growth. Conclusions: Nutrient inputs, temperature, and hydrological conditions significantly influence cyanobacterial blooms. Understanding these factors is crucial for implementing effective water management strategies to reduce algal proliferation and protect freshwater quality.
Let (X,d,μ) be a space of homogeneous type and L be a nonnegative self-adjoint operator on L2(X) whose heat kernels satisfy Gaussian upper bounds. In this article, we introduce the weighted variable Besov space associated with the operator L and demonstrate that Peetre maximal functions can be used to characterize this space. Furthermore, we provide a detailed study of its atomic decompositions.
تتناول هذه الدراسة تدريب القوة العضلية في حالتي التقلص المركزي والتقلص اللامركزي، وتأثيرهما على كمية كريات الدم البيضاء والتغيرات التي تحدث فيها، بغية معرفة مدى تأثير كل نمط تدريب على هذا المكون الدموي، وإن كان الكريات البيض تعد مبينا لما يحدث على مستوى النسيج العضلي المتعرض لتدريب القوة العضلية في هاذين النمطين، وذلك لدى عينة قصدية من نخبة رياضة الجودو قوامها 10 رياضيين مقسمين إلى مجموعتين، مجموعة معنية بالتقلص المركزي والأخرى بالتقلص اللامركزي، واعتمدنا على الاختبارات البدنية (1RM) لتقنين الأحمال حسب متطلبات الطريقة المستخدمة في الحصة التجريبية (10×10)، وعلى التحليلات الدموية في 3 مراحل (قبلي، بعدي، تتبعي). وبعد جمع البيانات ومعالجتها إحصائيا تم تأكيد الفرضية القائلة بأن تأثير الحصة التدريبية للقوة العضلية المقترحة يختلف بشكل كبير حسب حالات التقلص العضلي (المركزي، اللامركزي)، وخلصنا إلى أن تدريب القوة العضلية يختلف تأثيره على كريات الدم البيضاء حسب نوع التقلص العضلي، وأن النمط اللامركزي يتميز بإحداث تلف كبير على مستوى النسيج العضلي وفترة استشفاءه كبيرة لكن نتائجه أفضل، مقارنة بالنمط المركزي. الكلمات المفتاحية: التدريب الرياضي؛ القوة العضلية؛ التقلص المركزي؛ التقلص اللامركزي؛ كريات الدم البيضاء؛ تلف الخلايا العضلية.
Résumé : Centrée sur l’adaptation linguistique et culturelle des textes littéraires en classe de FLE, la présente contribution étudie les effets du recours aux textes adaptés sur la compréhension. Une compréhension réelle, qui suppose l’exploitation de tous les éléments linguistiques et culturels que contiennent les textes originaux, est en effet freinée par les omissions effectuées par les enseignants. Ces omissions, même si elles sont effectuées au niveau des séquences descriptives, nuisent à la compréhension des supports lus. Ce sont les résultats obtenus suite aux expérimentations menées et à la comparaison des textes originaux aux textes adaptés.
Mots-clés : Adaptation linguistique et culturelle ; textes littéraires ; classe de FLE ; compétence de compréhension
The field of food preservation has seen remarkable advancements, driven by the need to enhance food quality, safety, and sustainability. This paper provides a comprehensive examination of the latest food preservation technologies, detailing their principles, applications, and impacts on the food industry. Traditional methods such as canning, freezing, and drying are discussed alongside innovative techniques like high-pressure processing (HPP), pulsed electric fields (PEF), and cold plasma. Emphasis is placed on the benefits these advanced methods offer, including extending shelf life, preserving nutritional and sensory qualities, and reducing food waste. The review also addresses the challenges associated with each method, such as equipment costs, scalability, and potential health effects. By synthesizing current research and technological developments, this paper aims to provide valuable insights into how these technologies can be utilized to optimize food preservation processes. It highlights the importance of these advancements for pedagogy, scientific research, and societal benefits. Furthermore, the review underscores the necessity for continued research to address existing challenges and enhance the efficiency and applicability of these technologies. This comprehensive analysis is intended to assist researchers, industry professionals, and policymakers in understanding the state of food preservation technologies and promoting their use to improve food quality and safety.
