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)

Abstract The conflict that took place in Libya in 2011, up to the present moment, has greatly affected the electrical power network and resulted in the rise of the voltage instability problem. This was due to loss of the some major transmission lines and certain generation units. Owing to the fact that the southern region of the Libyan network has no generation units, voltage drop phenomena has become a common problem as a result of the long transmission distance, which is approximately 750km. A proposed solution in order to solve this problem is via the utilization of small mobile generation units at the network weak points. This thesis revolves around discussing the voltage instability problem within the Libyan Network and how it can be enhanced when small and mobile generation units are connected to the network weak points. It will also establish and identify where the most weakened buses and regions are so that the mobile units should be connected for the attainment of optimized solution. Moreover, this solution was proposed as it can solve not only the voltage instability problem, but it will also solve the inadequacy in generation issue by circulating additional power within the network. Hence, reduce the load shedding phenomena. Furthermore, the thesis also includes future recommendations to improve and enhance the Libyan network by the addition of new 220kV and 400kV transmission lines that will enable the network to cope with the load growth in the future
ربيع محمد عمر (2014)

Modeling, Specification & Evaluation Language (MOSEL), tool used for the performance and reliability modeling of communication systems, computers, and manufacturing systems, once the system is specified using this language. The modeling language is part of the evaluation environment. Once the system is specified using the language, the evaluation environment takes place by executing the performance analyses of the model, and calculating the steady state probabilities . After this stage, results can be collected in the result file or in graphics mode using the Intermediate Graphical Language (IGL), where the aim of this paper is to give an overview of mosel and to show a real example under windows platform.
wael saleh mohamed abughres, Mohamed Ahmed Ramadan Mgheder, Ahmed B. Abdurrman (8-2017)