Faculté des Sciences

Permanent URI for this community

http://dspace.univ-skikda.dz:4000/handle/123456789/172

Browse

Now showing 1 - 6 of 6

Effect of Marble Powder and Dolomite on the Mechanical Properties and the Thermal Stability of Poly(vinyl chloride)
(Asian Journal of Chemistry Vol. 22, No. 9, 6687-6692, 2010) ZAGHDOUDI , Rachida; BOUNAMOUS , Ghada; MEGHEZZI , Ahmed; DJAZI , Faycal
The polymers are materials whose proprieties can be improved by adding various additives such as the fillers which can be mineral or organic compounds. In this study, we are interested in the possibility of improving the mechanical proprieties and the thermal stability of poly(vinyl chloride) (PVC) by adding local mineral fillers i.e., powder of marble and the dolomite. The composites PVC/dolomite and PVC/ marble (fillers: 0, 5, 10, 15 and 20 phr) have been prepared. The test- tubes have been made up of the different composites through three stages i.e., blending, pressing and cutting up. These test-tubes have been then put under mechanical tests (tensile test and impact IZOD) and a thermo test (Vicat softening temperatures) whereas, the thermo stability of various components has been evaluated by the dehydrochlorination. The results have shown that there is a notable improvement of mechanical and thermo proprieties which is interpreted by the increase of the Vicat softening temperatures and an extension of stability time.
The Development of Mountain Agriculture in the wilaya of Skikda (eastern Algeria) Facing New Legal Framework. "Program Evaluation in Action and Future Prospects".
(International Journal of Advanced Research , Volume 3, Issue 5, 824-834, 2015-05) Foufou , Ammar
The development of mountain agriculture in Algeria is closely related to the presence and involvement of Man as a key player who, under duress, abandoned his land situated in mountainous and rural areas. One of the key objectives of the public authorities is essentially based on the possibility of maintaining agricultural activities in mountain areas, all in does not dissociating the rural population, considered as the real engine of any rural development. Agricultural land in these areas, often "private" property and "arch" is hampered by a number of endogenous constraints in the image of excessive inheritance and fragmentation of land generation to generation. Therefore, the agricultural area exploited in these areas is seen to decline, on the one hand, and new agricultural investors targeting these areas are struggling to realize their projects fault of farmland on the other. This issue has created a strong demand for land in rural areas often located in forested areas. Therefore, a set of legal rules has emerged. This is the Executive Decree No. 01/87 from 05 April 2001 laying down the conditions and terms of use exemption under the provisions of Article 35 of Law No. 84-12 of June 23, 1984 amended and supplemented, establishing general forest regime, in particular Article 5. In the wilaya of Skikda, a program in this framework spanning 03 phases was initiated targeting mountainous municipalities to secure the population in these rural areas and extend as far as possible, their agricultural area farmed.
National food safety depends on the modernization and mechanization of agriculture
(INTERNATIONAL JOURNAL OF SCIENCES AND NATURAL RESOURCES (IJSNR) NUMBER 1 JUNE , 2022) Foufou , Ammar
Since independence, Algeria's economy has relied on the hydrocarbons sector, which represents 98% of the population. This has caused all economic indicators and national policies, whether development or related to the state budget, to be anchored directly to the figures for the export of gas and oil. Algeria has been unable, for more than half a century, to establish a diversified and affluent economy, in light of the dominance of the container economy, which is not immune from external crises and the requirements of the international market. Algeria is distinguished from the countries of the Mediterranean basin by its vast area, the diversity of its climate and environmental systems, and its unique geographical structure. This has made its space characterized by four climatic systems, from the Mediterranean in the north to the coastal climate in the far south. Climate diversity is logically related to the diversity of resources, ecosystems and agricultural products throughout the year. These natural advantages also allowed some products to be impersonated twice a year. All scientific experiments and economic approaches have reached the inevitable conclusion that we must modernize the agricultural sector through modernizing its structures, modernizing its production factors, and, in particular, introducing modern technology into all stages of the agricultural production process in its various divisions and specializations, and in various climatic regions.
A New Information-Based Heuristic for Distributed DDoS Detection and Mitigation: Distributed and Collaborative DDoS Detection
(International Journal of Organizational and Collective Intelligence Volume 12 • Issue 4, 2022) Nafir , Abdenacer; Mazouzi , Smaine; Chikhi ,Salim
In this paper a novel collective method for DDoS detection is introduced. The method is distributed and implemented as a multi-agent system, and where local decision is based on an informationbased heuristic, namely the entropy. According the calculated entropy a router exchange data with its neighbors aiming at collectively decide if a DDoS is ongoing or not. Most of the works of the literature that are based on the entropy they have used source addresses. The authors’ method is based on the entropy of the distances traveled by the packets, so spoofing IP packets will be hard to perform by hackers. Each router combines its decision with those of its neighbors. Such a collective detection allows to apply defense against the attack despite the victim is out of service or cannot perform DDoS mitigation because the traffic is congested in its neighborhood. Conducted experiments using the platform OMNet++ show the potential of the new method for efficient collaborative and distributed detection and mitigation of DDoS attacks.
Self-Adaptation Through Reinforcement Learning Using a Feature Model
(International Journal of Organizational and Collective Intelligence Volume 12 • Issue 4, 2022) Boulehouache , Soufiane; Mazouzi , Smaine; Ouareth , Selma
Typically, self-adaptation is achieved by implementing the MAPE-K Control Loop. The researchers agree that multiple control loops should be assigned if the system is complex and large-scale. The hierarchical control has proven to be a good compromise to achieve SAS goals, as there is always some degree of decentralization but it also retains a degree of centralization. The decentralized entities must be coordinated to ensure the consistency of adaptation processes. The high cost of data transfer between coordinating entities may be an obstacle to achieving system scalability. To resolve this problem, coordination should only define between entities that require communication between them. However, most of the current SAS relies on static MAPE-K. In this article, authors present a new method that allows changing the structure and behavior of loops. Authors base on exploration strategies for online reinforcement learning, using the feature model to define the adaptation space.
Elimination des polluants organiques par Adsorption sur un matériau issu d’une plante naturelle
(Faculté des Sciences, 2024-06-27) Bouhezza, Ikram; Bouhali, H
La pollution des eaux des rejets industriels est un sérieux problème dans plusieurs pays. Pour réduire les effets néfastes de ces polluants, plusieurs procédés de traitement des eaux sont mis en oeuvre, en particulier, la technique de l’adsorption. La présente étude consiste à étudier l’élimination des deux colorants (le Cristal Violé et le Vert Malachite) par un adsorbant naturel (la plante X). Le biosorbant a été préalablement caractérisé par diffraction des rayons X (DRX) et Spectroscopie Infrarouge à Transformée de Fourier (IR-TF). Les essais d'adsorption nous ont permis de constater que la capacité d'adsorption est influencée par divers paramètres liés au milieu et a l'adsorbant. Pour le CV (une quantité de 0.4 g de la plante X, un pH de 3, les températures 10, 20, 50°C et une vitesse d’agitation de 700 tr/min) donne les meilleurs rendements ainsi Pour le VM a des conditions optimale de (0.4 g de la plante X, pH de 8, les températures 20,30, et 50°C et une vitesse d’agitation de 1000 tr/min). L’ensemble des résultats obtenus montre que la cinétique d’adsorption des colorants sur le matériau est bien décrite par le modèle du second ordre. Les isothermes d’adsorption des systèmes adsorbant/adsorbât étudiés sont décrites de manière satisfaisante par le modèle mathématique de Langmuir et Freundlich.

Browse

Browsing Faculté des Sciences by Issue Date

Results Per Page

Sort Options