Les enfants et l’Internet les influences négatives et méthodes de protection

لقد أحدث ظهور الأنترنت تأثيرات هائلة في كل المجتمعات العالمية، حيث مست تلك التأثيرات كل الفئات العمرية دون استثناء. غير أنه من بين الفئات الأكثر تأثرا بهذه الوسيلة الاتصالية هي فئة الأطفال، وهذا نظرا لطبيعة الاستخدام الخاطئ والسلبي الذي يترك آثاره على الصحة الجسدية والنفسية والسلوكية للأطفال. لكن وبالرغم من ذلك فهناك من الوسائل والطرق الاجتماعية والقانونية والتقنية ما يمكن أن نحد به من تلك الآثار السلبية للأنترنت على الأطفال.L’apparition de l’internet a profondement influence les sociétés internationales. En effet, ces influences ont touché toutes les tranches de different age, sans exception. Cependant, parmi ces tranche les plus influencées par ce moyen de communication est bien la tranche des enfants. Et cela est du à la nature fautive et négative de l’utilisation qui résulte des effets de santé: corporel psychiques et comportement aux vis- à -vis ces enfants. Malgré les effets négatifs envisagés. Il existe des moneys et des méthods sociaux, légals et techniques permettant de limiter ces effets négatifs de l’internet sur les enfants.&nbsp

Impact of the use of collaborative learning (peer learning) on learning some basic skills in volleyball

ﻫﺩﻓﺕ ﺍﻟﺩﺭﺍﺴﺔ إلى التعرف على تأثير ﺃﺴﻠﻭﺏ ﺍﻟﺘﻌﻠﻡ ﺍﻟﺘﻌﺎﻭﻨﻲ(ﺘﻌﻠﻡ بالأﻗﺭﺍﻥ)  ﻓﻲ ﺘﻌﻠـﻡ ﺒﻌﺽ ﺍﻟﻤﻬﺎﺭﺍﺕ الأساسية ﺒﺎﻟﻜﺭﺓ ﺍﻟﻁﺎﺌﺭﺓ ( الإرسال الساحق، حائط الصد . الضرب الساحق) وإبراز العلاقة  بين ﺃﺴﻠﻭﺏ ﺍﻟﺘﻌﻠﻡ ﺍﻟﺘﻌﺎﻭﻨﻲ (ﺘﻌﻠﻡ بالأﻗﺭﺍﻥ)  و ﺘﻌﻠـﻡ ﺒﻌﺽ ﺍﻟﻤﻬﺎﺭﺍﺕ الأساسية ﺒﺎﻟﻜﺭﺓ ﺍﻟﻁﺎﺌﺭﺓ ( الإرسال الساحق، حائط الصد . الضرب الساحق) وافترض الباحثان لأسلوب ﺍﻟﺘﻌﻠﻡ ﺍﻟﺘﻌﺎﻭﻨﻲ (ﺘﻌﻠﻡ ﺍﻹﻗﺭﺍﻥ)  تأثير ايجابي في ﺘﻌﻠـﻡ ﺒﻌﺽ ﺍﻟﻤﻬﺎﺭﺍﺕ الأساسية ﺒﺎﻟﻜﺭﺓ ﺍﻟﻁﺎﺌﺭﺓ ( الإرسال الساحق، حائط الصد، الضرب الساحق).  فضلا عن وجود علاقة ارتباط معنوية بين أسلوب ﺍﻟﺘﻌﻠﻡ ﺍﻟﺘﻌﺎﻭﻨﻲ و ﺘﻌﻠـﻡ ﺒﻌﺽ ﺍﻟﻤﻬﺎﺭﺍﺕ الأساسية ﺒﺎﻟﻜﺭﺓ ﺍﻟﻁﺎﺌﺭﺓ ( الإرسال الساحق، حائط الصد . الضرب الساحق).    ﻭﻗﺩ ﺍﺴﺘﺨﺩم الباحثان ﺍﻟﻤﻨﻬﺞ  ﺍﻟﺘﺠﺭﻴﺒﻲ لملائمته ﻭﻁﺒﻴﻌﺔ ﺍﻟﺒﺤﺙ ﻭﻗﺩ ﺍﺸـﺘﻤﻠﺕ ﻋﻴﻨﺔ ﺍﻟﺒﺤﺙ ﻋﻠﻰ(40) ﻁﺎلبا ﻤﻥ طلبة قسم التربية البدنية والرياضية لجامعة بومرداس، تم إجراء الاختبارات ﺍﻟﻘﺒﻠﻴﺔ ﺍﻟﺨﺎﺼﺔ ﺒﺎﻟﻤﻬﺎﺭﺍﺕ ﻗﻴﺩ ﺍﻟﺒﺤـﺙ تم تقسيم العينة إلى مجموعتين متساويتين مع مراعاة التجانس بين المجموعتين، ﻭﺒﻌـﺩ ﺘﻁﺒﻴـﻕ  ﺍﻟﻤـﻨﻬﺞ ﺍﻟﺘﻌﻠﻴﻤﻲ و الاختبارات ﺍﻟﺒﻌﺩﻴﺔ ، استعان الباحثان ﺍﻟﻭﺴﺎﺌل الإحصائية الملائمة ﺘـﻡ ﺍﻟﺘﻭﺼـل إلى ﻨﺘﺎﺌﺞ ﺍﻟﺒﺤﺙ التالية : تأثير الأسلوب التعاوني على تعلم بعض المهارات الأساسية في الكرة الطائرة مجال البحث.  - هناك علاقات ارتباط معنوية بين دقة المهارات بالكرة الطائرة قيد البحث وتركيز الانتباه.The study aims at identifying the effect of cooperative learning (peer learning) on learning some basic skills of volleyball (ace, block, spike), highlighting the relationship between peer learning and learning some basic skills of volleyball (the ace, the block, the spike). The researchers hypothesized that the peer learning has a positive effect on learning some basic volleyball skills. Moreover, there is a significant correlation between them.    The researchers used the Empirical Research which is more suitable for this kind of study. The sample included 40 students from the “Department of Physical and Sports Education” of the University of Boumerdes. The pre tests of these skills were done. The students were divided into two equal groups. After applying the teaching method and doing post tests, the researchers used the appropriate statistical methods. results were as follow:     - The effect of the cooperative method (peer learning) on learning some basic skills of volleyball.      - There are significant correlations between the accuracy of volleyball skills and the attention’s concentration

The principle of recognition and its role in converging between Islamic doctrines

يُعتبر مشروع التقريب بين المذاهب الإسلامية من المحاولات الجادة لتحقيق الوحدة الإسلامية، هذا المشروع الذي سعى إلى تضييق الخلاف بين المذاهب الإسلامية حتى تتمكّن المجتمعات الإسلامية من تجاوز أزماتها المذهبية ومعالجة مشكلاتها الأخلاقية، ولأنّ الثقة أصبحت شبه معدومة بين المذاهب الإسلامية، جاءت هذه الورقة البحثية لتبيّن أنّ مبدأ الاعتراف ضروري لإرجاع هذه الثقة المسلوبة.أمّا النتائج المتوصّل إليها في هذا البحث أكّدت على ضرورة انغماس المجتمعات الإسلامية في بعض المفاهيم، على غرار مبدأ الاعتراف، وفكرة المواطنة، وبالتالي تفعيل الحوار الإسلامي-الإسلامي ونجاحه مرهون بمدى تحقيق العُبور من فكرة المذهبية والطائفية إلى فكرة المواطنة التي تؤمن بحريّة الاعتقاد والعيش الإنساني المشترك. The project of convergence between Islamic doctrines is a serious attempt to maintain Islamic unity. Accordingly, it aimed at narrowing the differences between Islamic doctrines, which may help Islamic societies exceed doctrinal crises and move to address ethical problems. Yet, due to the lack of trust among Islamic doctrines, this paper demonstrates that the recognition principle is necessary to restore that trust. The results stressed Islamic societies should be immersed in some concepts, such as the concepts of recognition and citizenship. Thus, Islamic-Islamic dialogue activation and success depends on the ability of exceeding sectarianism and confessional ideas, and shift to the idea of citizenship, which promotes freedom of religious belief and coexistence

Experimental and numerical study of behaviour of reinforced masonry walls with NSM CFRP strips subjected to combined loads

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).Near surface mounted (NSM) carbon fibers reinforced polymer (CFRP) reinforcement is one of the techniques for reinforcing masonry structures and is considered to provide significant advantages. This paper is composed of two parts. The first part presents the experimental study of brick masonry walls reinforced with NSM CFRP strips under combined shear-compression loads. Masonry walls have been tested under vertical compression, with different bed joint orientations 90ffi and 45ffi relative to the loading direction. Different reinforcement orientations were used including vertical, horizontal, and a combination of both sides of the wall. The second part of this paper comprises a numerical analysis of unreinforced brick masonry (URM) walls using the detailed micro-modelling approach (DMM) by means of ABAQUS software. In this analysis, the non-linearity behavior of brick and mortar was simulated using the concrete damaged plasticity (CDP) constitutive laws. The results proved that the application of the NSM-CFRP strips on the masonry wall influences significantly strength, ductility, and post-peak behavior, as well as changing the failure modes. The adopted DMM model provides a good interface to predict the post peak behavior and failure mode of unreinforced brick masonry walls.Peer reviewe

Strength and durability of low-impact environmental self-compacting concrete incorporating waste marble powder

This research studies the effect of waste marble powder (WMP) as substitute of Portland cement on strength and durability of self-compacting concrete (SCC) in order to produce SCC with reduced impact environmental. For this purpose, five mixtures were designed in which four mixtures contained WMP at substitution levels of 5, 10, 15, 20%, and mixture included only the Portland cement as control mix. The realized tests are compressive strength at 3, 7 and 28 days, water capillary absorption, water absorption by immersion and sulfate attack. The results show a reduction in the compressive strength with increasing WMP content. The use of WMP was found to increase both of the water capillary absorption and water absorption by immersion. SCC containing WMP subjected to magnesium sulfate attack presented a lower expansion and higher resistance to sulfate aggressions

Effect of limestone powder as a partial replacement of crushed quarry sand on properties of self-compacting repair mortars

Self-compacting repair mortars (SCRM) are particularly desired for the rehabilitation and repair of reinforced concrete structures. The properties of SCRM can be improved by using chemical, mineral, polymer and fiber additives. In limestone quarries, considerable quantities of limestone fine powder are obtained during the process of crushing rock. These fine powders are being collected and their utilization is a big problem from the aspects of disposal, environmental pollution and health hazards. The introduction of limestone powder as cement and sand replacement present interesting possibilities to reduce the cement cost production, CO2 emission and the conservation of natural resources. The effects of limestone powder content in crushed sand on the properties of SCRM are not studied. An experimental study was undertaken to find out the effect of limestone powder content on fresh and hardened properties of SCRM. SCRM mixtures were prepared using crushed sand partially replaced with limestone powder at varying percentages up to 30%. Results indicate that the limestone powder as sand replacement significantly improves the fresh and hardened properties of SCRM with a content ranging from 10 to 15%. The use of limestone powder in repair mortar and concrete application would offer technical, economical and environmental advantages for concrete producers.Self-compacting repair mortars (SCRM) are particularly desired for the rehabilitation and repair of reinforced concrete structures. The properties of SCRM can be improved by using chemical, mineral, polymer and fiber additives. In limestone quarries, considerable quantities of limestone fine powder are obtained during the process of crushing rock. These fine powders are being collected and their utilization is a big problem from the aspects of disposal, environmental pollution and health hazards. The introduction of limestone powder as cement and sand replacement present interesting possibilities to reduce the cement cost production, CO2 emission and the conservation of natural resources. The effects of limestone powder content in crushed sand on the properties of SCRM are not studied. An experimental study was undertaken to find out the effect of limestone powder content on fresh and hardened properties of SCRM. SCRM mixtures were prepared using crushed sand partially replaced with limestone powder at varying percentages up to 30%. Results indicate that the limestone powder as sand replacement significantly improves the fresh and hardened properties of SCRM with a content ranging from 10 to 15%. The use of limestone powder in repair mortar and concrete application would offer technical, economical and environmental advantages for concrete producers.Self-compacting repair mortars (SCRM) are particularly desired for the rehabilitation and repair of reinforced concrete structures. The properties of SCRM can be improved by using chemical, mineral, polymer and fiber additives. In limestone quarries, considerable quantities of limestone fine powder are obtained during the process of crushing rock. These fine powders are being collected and their utilization is a big problem from the aspects of disposal, environmental pollution and health hazards. The introduction of limestone powder as cement and sand replacement present interesting possibilities to reduce the cement cost production, CO2 emission and the conservation of natural resources. The effects of limestone powder content in crushed sand on the properties of SCRM are not studied. An experimental study was undertaken to find out the effect of limestone powder content on fresh and hardened properties of SCRM. SCRM mixtures were prepared using crushed sand partially replaced with limestone powder at varying percentages up to 30%. Results indicate that the limestone powder as sand replacement significantly improves the fresh and hardened properties of SCRM with a content ranging from 10 to 15%. The use of limestone powder in repair mortar and concrete application would offer technical, economical and environmental advantages for concrete producers

Effect of limestone powder as a partial replacement of crushed quarry sand on properties of self-compacting repair mortars

Self-compacting repair mortars (SCRM) are particularly desired for the rehabilitation and repair of reinforced concrete structures. The properties of SCRM can be improved by using chemical, mineral, polymer and fiber additives. In limestone quarries, considerable quantities of limestone fine powder are obtained during the process of crushing rock. These fine powders are being collected and their utilization is a big problem from the aspects of disposal, environmental pollution and health hazards. The introduction of limestone powder as cement and sand replacement present interesting possibilities to reduce the cement cost production, CO2 emission and the conservation of natural resources. The effects of limestone powder content in crushed sand on the properties of SCRM are not studied. An experimental study was undertaken to find out the effect of limestone powder content on fresh and hardened properties of SCRM. SCRM mixtures were prepared using crushed sand partially replaced with limestone powder at varying percentages up to 30%. Results indicate that the limestone powder as sand replacement significantly improves the fresh and hardened properties of SCRM with a content ranging from 10 to 15%. The use of limestone powder in repair mortar and concrete application would offer technical, economical and environmental advantages for concrete producers

Learner Autonomy in Distance Learning under the Circumstance of Corona virus: Challenges and Opportunities

After the spread of Corona virus, the Algerian government like many other countries has closed its universities. This crisis has led the ministry of higher education and scientific research to adopt online-courses. Formal learning has, most of the time, been associated to inside classroom practices and activities; however, little attention is given to learning outside the classroom in the absence of the teacher.Thus, this paper attempts to explore the effectiveness of distance learning as an alternative option to cope with this unprecedented situation and to develop learner autonomy. Two questionnaires were administered to 22 teachers and 72 students at Ahmed Zabana University of Relizane-Algeria- via email and Facebook. The respondents of this research include 10 teachers and 38 EFL students.Results have shown that though distance learning is an appreciated method to make students experience autonomy during this time, it is still difficult and challenging due to students’ psychological instability, teachers’ lack of online teaching experience and bad network quality

Experimental study on the reuse of cathode ray tubes funnel glass as fine aggregate for developing an ecological self-compacting mortar incorporating metakaolin

Industrial waste causes a lot of pollution, particularly electrical and electronic waste (WEEE) such as glass cathode ray tubes (CRT) which create environmental pollution and health hazards. The field of civil engineering, like sectors in the world has leaned towards sustainable development by emphasizing environmental aspects as an important goal. This strategy is achieved by recycling and reusing polluted industrial sites, materials, waste, by-products or industrial residues. In this paper a study was carried out to explore the use of recycling waste glass obtained from crushed CRT as fine aggregate, and metakaolin (MK), as a partial replacement of Ordinary Portland cement (OPC) for the development of eco-self-compacting mortar (SCM). Here, OPC is replaced by 5, 10, and 15% of MK by weight, and fine aggregate is replaced by 0, 10, 20, 30, 40 and 50% of CRT by weight. The mini-slump flow and V-funnel flow time of fresh SCM are evaluated. The compressive strength, flexural strength, water absorption, resistance to high temperature, porosity and microstructure of hardened SCM are also performed. These experiments indicate that using CRT glass with MK increases the flowability of SCM and reduces the dosage of superplasticizer (SP). The incorporation of 10% MK with CRT mixture showed higher mechanical properties, lower porosity and dense structure. Moreover, the water absorption and resistance to high temperature have been improved by 10% and 15% of the MK group respectively, for all SCM made with CRT glass. This combination of MK and CRT glass as a fine aggregate in SCM is a low-cost ecosystem for a much cleaner environment