Abstract In order to ensure the promise of anytime-anywhere communication to the customers, Mobile operators must be able to support a large number of users over a large coverage area. So Coverage and Capacity are important issues in the planning process for Third Generation (3G) mobile networks. The planning process aims to allow the maximum number of users sending and receiving adequate signal strength in a cell. In Code division multiple access (CDMA), the Coverage and capacity are not independent of each other as in GSM, it is interference-limited system, meaning that if the traffic increases, the serving cell radius decreases, hence the term cell breathing occurs. This work studies the capacity and coverage of a macrocell CDMA network. The cell breathing effect is studied and a new criteria to link Capacity and Coverage is developed, it is named by Capacity-Coverage Product; CCP. Different designations of CCP formula are given. The influencing of various system parameters on this CCP are studied. Knowing this CCP, the capacity and coverage become straight to estimate. The user distribution is very important issue. Most of previous studies treat user distribution as uniform. This thesis considers the case of non uniform user distributions where a more realistic distribution is chosen. A new interference distribution factor is initiated. The impact of this factor on the capacity and coverage is studied. Existing of Hotspot regions of traffic will cause coverage shrinkage. Installation of hotspot microcells BS inside existing macrocell BS is one possible solution to such situations. In this work a microcell is introduced within the macrocell and a new system parameters are obtained such that the coverage and performance are maintained while the capacity is increased.
محمد عبدالرزاق العالم (2007)

Abstract Voice over IP (VoIP) uses the Internet Protocol (IP) to transmit voice as packets over an IP network, like the Internet, Intranets and Local Area Networks (LAN). Here the voice signal is digitized, compressed and converted to IP packets and then transmitted over the IP network. However, at the receiving end, some packets may be missed in its way due to network congestion. This packets loss degrades the quality of speech at the receiving end of a voice transmission system in the IP network. Since the voice transmission is a real time process, the receiver cannot request for retransmission of the missing packets. High speed networks provide real time variable bit rate service with packet loss requirements. The burstiness of the correlated traffic makes dynamic buffer management highly desirable to satisfy the Quality of Service (QoS) requirements. This thesis presents an algorithm to improve and optimize the Adaptive Buffer Allocation Scheme to deal with input traffic based on loss of consecutive packets in data streams and buffer occupancy levels. Buffer is designed to allow the input traffic to be partitioned into different priority classes, and based on the input traffic behavior it controls the threshold dynamically. This scheme allows input packets to enter into buffer if its occupancy level is less than the threshold value for priority of that packet. The threshold is dynamically varied in runtime based on packet loss behavior. The performance evaluation is carried out using simulation and is carried out for two and multiple priority classes of the input traffic "real time and non real time classes". The simulation results show that the Modified Adaptive Partial Buffer Sharing (ADPBS) has better performance than Adaptive Partial Buffer Sharing under the same traffic conditions.
اسماء احمد الكيش (2010)

يمر العالم بمرحلة انتقالية تموج بتحولات جذرية عميقة وشاملة في كافة المجالات، مرحلة تنكسر فيھا القيود وتلغى الحدود وتنفتح الأسواق ، وتشتعل المنافسة، ويتعاظم دور التكنولوجيا الحديثة التي تلعب دوراً رئيسا ً في إحداث ھذه التحولات وأھمھا التحول من الأساليب التقليدية في الإدارة إلى الأساليب الإلكترونية، وبات مصطلح الحكومة الإلكترونية ھو عنصر تميز المؤسسات والهيئات والدول. يسعى هذا البحت إلى إتاحة المحتوى العلمي للإدارة الإلكترونية وذلك من خلال سرد لمحة تاريخية عنها ومميزاتها وسبيل الإستفادة منها بجميع المجالات وخاصة بمجال التعليم والتطرق الي جامعة طرابلس كحالة دراسية.
وائل صالح محمد أبوغريس, عطية محمود البحباح, محمد أحمد مغيدر(6-2022)