In this paper, imposing the Hadamard Transform (HDT) on Orthogonal Space-Time Block Codes (OSTBC) schemes using multiple transmit antennas is proposed in order to increase the reliability and improve the error performance of wireless communications. It is referred to as joint Hadamard transform and OSTBC schemes with multiple transmit antennas. However, HDT is used to change the location of constellation points by converting the transmit symbols of OSTBC system, and hence extending the Euclidean distance between transmit symbols for a precise detection. Simulation results demonstrated that increasing the number of transmit antennas in OSTBC systems employing 8-PSK improves the Bit Error Rate (BER) performance as in the case of OSTBC 2×2 scheme where an SNR of about 13.5 dB is required to achieve a BER of 〖10〗^(-6), while only about 7 dB in OSTBC 8×8 scheme is required to obtain the same error probability. It is also demonstrated that imposing the Hadamard criteria on the OSTBC 2×2, 4×4, and 8×8 schemes has showed a performance improvement of about 3 dB, 6 dB and 9 dB, respectively, as compared to the conventional OSTBC systems.
Taissir Y. Elganimi, Marwan B. Elkhoja(4-2019)

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)

In this paper, we present an analytical traffic model for the Universal Mobile Telecommunication Systems (UMTS). In 3G networks we have dynamic capacity that depends on the interference levels in the covered area and the number of active users. This implies that the distance of the mobile user from the base station is also an important factor because of the signal fading. The first part of this paper is an algorithm written in c++ programming language that distributes users in different zones assuming that the cell area is virtually divided into Z zones depending on the number of users. The last part of this paper we build a mathematical model of a 3G cell using the above assumption , and to prove, that the product form holds in the case of two cells with uniform and non uniform traffic. By this result more complicated networks can be analyzed, to calculate the performance measures of the network.
WAEL S. ABUGHRES, MIKE E. WOODWARD(6-2006)