إسهامات المجتمع الدولي في مكافحة ظاهرة الهجرة غير الشرعية = Contributions of the international community in combating the phenomenon of Illegal Immigration

ملخ ص يهدف هذا البحث إلى التعرف على ظاهرة الهجرة غير الشرعية ومسؤولية المجتمع الدولي تجاه هذه الظاهرة، وكذلك يهدف إلى بيان أسباب ودوافع ومبررات الهجرة غير الشرعية. ولقد اتبع الباحث المنهج الاستقرائي والمنهج المقارن لاستقراء المصادر المتعلقة بماهية الهجرة غير الشرعية. ولقد توصل الباحث إلى العديد من النتائج من بينها: معرفة التطور التاريخي للهجرة غير الشرعية والمراحل التي تعرضت لها الهجرة غير الشرعية منذ بدايتها بعد الحرب العالمية الثانية وصولا إلى مرحلة تشجيع الهجرة من جانب الدول الأوروبية لتحقيق أهداف التنمية في هذه الدول وصولا إلى مرحلة وقف الهجرة ومحاربتها

Clustering Approach In Wireless Sensor Networks Based On K-Means: Limitations And Recommendations

Clustering approach in wireless sensor network is very important, the structure of cluster and how to improve it is a first challenge that faced the developers, because of it represent as a base for design the cluster-based routing protocol. One of most popular cluster algorithms that utilizing into organize sensor nodes is K-means algorithm. This algorithm has beneficial in construct the clusters for various real-world applications of WSN.K-means algorithm suffering from many drawbacks that hampering his work.The lack of adequate studies that investigates in the limitations of this algorithm and seek to propose the solutions motivated us to do this study. In this paper the limitations of K-means and some suggestions are proposed. These suggestions can improve the performance of K-means, which will be reflected on saving the energy forsensor nodes and consequently maximize the lifetime of the wireless sensor networks

An Improved LEACH Algorithm Based On Fuzzy C-Means Algorithm And Distributed Cluster Head Selection Mechanism.

The beneficial capability of Wireless Sensor Networks (WSNs) to check numerous types of environmental settings via detection mechanisms on the physical state of matters discovered through researches, has attracted great interest in many quarters. Significant necessities in a majority of applications related to sensor networks are the extensive duration of network lifespan. Towards the fulfillment of such requirements, the clustering sensor nodes is an efficient method for the purpose of achieving these ends. The fundamental goal of WSN routing protocol are in maintaining the equilibrium of network energy usage, and in stretching the total network lifespan. The most famous protocol that utilized clustering technique is Low Energy Adaptive Clustering Hierarchy (LEACH). In LEACH algorithm, the random manner is used to select specific nodes as a cluster heads. In addition, the resulting clusters suffer from an imbalance in cluster size. In this study, the LEACH issues are solved by utilizing Fuzzy C-means algorithm (FCM) to form balanced clusters,which is followed by the selection of the cluster head in each cluster according to the energy of nodes and distance to the cluster centroid. The comparison of therecommended algorithm with LEACH algorithm is conducted, in relations to energy consumption and network lifetime. The result showed that our proposed algorithm has further advantage over LEAC