Volume 04
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Item Comparative Performanceof Subcarrier Schedulers in Uplink LTE-A under High Users' Mobility(University of Bahrain, 2015) Othman,Ali; Othman,Siddeeq Y.; Al-Omary,Alauddin ,; Al-Rizzo,HussainThis paper evaluates the effects of high mobility of Users Equipment (UEs) on the performances of different data rate services using four scheduling algorithms in the uplink of LTE system using the uplink Vienna simulator.The uplink reports Channel Quality Indicator (CQI), Precoding Matrix Indicator (PMI) and Rank Indicator (RI) to inform the evolved node base station (eNodeB or eNB) about the current channel state. We simulate 20 and 30 UEs switch at high mobility and different service demands. Simulation results show that under 100 kmh-1speed the Best CQI and Proportional Fair schedulersItem Implementation of Efficient Parallel Prefix Adders for Residue Number System(University of Bahrain, 2015) Kumar,CH. Pavan; Sivani,K.In this paper we proposed a high speed and area efficient Kogge-stone, Ladner-fischer and Knowles adders by modifying the existing architectures by eliminating the redundant black cells. Currently the speed of the multipliers are restricted by the speed of adders for partial products addition. The major problem with the binary addition is the carry chain delay, to address this problem most of the modern adder architectures are implemented using parallel prefix adders. The delay of the parallel prefix adders are directly proportional to the number of levels in the carry propagation stage. Due to the logarithmic delay of the parallel prefix adders delay problems have effectively reduced. Kogge-stone is one of the fastest adders. We has eliminated the redundant black cells and performed re-routing thus minimizing the logic delay compared to the previous adders. Coded modified architecture in Verilog HDL, Simulated and synthesized using Xilinx ISE. Compared the modified architectures of Kogge-stone, Ladner-fischer & Knowles adders are found to be an improvement in the delay with the previous adders.Item OFDM for Cognitive Radios: An overview Present Solutions and Future Directions(University of Bahrain, 2015) Begh,Gh. Rasool; Ajaz,Hussain MirSpectrum efficiency, high speed data transmission and security are the major requirements for new generation wireless communications. By integrating OFDM into physical layer of cognitive radio, we can achieve high speed data transmission with high spectrum utilization. In this article, we investigate the impediments for use of OFDM with cognitive radios. We discuss some of the solutions to overcome these problems and identify the need for further exploration taking into account the practical issues of synchronization errors between the transmitter and the receiver. We also discuss security issues related to cognitive radio networks and suggest some future research directions.Item Takagi-Sugeno Fuzzy System Accuracy Improvement with A Two Stage Tuning(University of Bahrain, 2015) Elragal,Hassan M.In this paper a method for improving accuracy of a Takagi-Sugeno type fuzzy system used in Matlab Fuzzy Logic Toolbox as genfis3 (Sugeno) is proposed. For this fuzzy system, the input space is partitioned using Fuzzy C-means (FCM) clustering algorithm and the consequent parameters are optimized using least square. This improvement is done in a two stage tuning using particle swarm optimization (PSO).In the first stage, PSO is used to optimize input membership functions (mean and variance) and consequent parameters of Takagi-Sugeno fuzzy system. In the second stage, PSO is used to optimize a weighting factor for the rules and a scaling universe of discourse for inputs and outputs variables. To simplify the tuning process and performing it in one optimization stage, a one stage tuning is also discussed to tune same parameters optimized in the two stage tuning. Experimental results with real data applied in data classification problem shows a consistency of getting higher classification accuracy with the proposed tuning methods over the original system.Item Load Prediction in Smart Grid Networks(University of Bahrain, 2015) Sivakoti,Karthik; Mozumdar,MohammadEfficient forecasting and load prediction for maintaining the accurate DR (Demand Response) ratio is a key factor in implementing and deploying the Smart-Grid networks [1]. There are a plethora of techniques and models suggested by forecasters over the decades, the most accurate and feasible being – artificial neural networks, linear regression technique and the curve fitting algorithm. Researchers have demonstrated extreme zeal and effort in devloping algorithms which could derive the best effeciency, thus saving excess production than demand. For example, the work descrbied in the paper [2] puts forward the prediction values to be at an accuracy of around 95%. A hybrid algorithm has been presented in this paper, which has been practically proved to have a forecasting efficiency much higher than the conventional methods. Using the artificial neural networks for training the model with historical data and fluctuations in demand, the linear regression method has been used for implementing the temperature sensitivity, namely – dew point, humidity, wind speed, seasonal variations and location of the smart-meter. Together along with the curve fitting algorithm, the proposed hybrid algorithm has been practically implemented by taking data from smart-meters across the United States to determine their efficiency of implementation. The proposed algorithm described in this paper encountered a marvelous prediction accuracy of 99.2% - 99.45%, which promises vast reduction in the power wasted by power utility companies owing to the mismatch within the DR rates from the consumer end and is far accurate than the predictions made by [2].Item FAHP Approach to Rank Educational Websites on Usability(University of Bahrain, 2015) Nagpal ,Renuka; Mehrotra ,Deepti; Bhatia,Pradeep Kr.; Bhatia, ArunWebsite of an educational institute is a platform that gives complete information about the organization. These websites are frequently visited by students, parents aspiring students and their parents, university faculties and other personnel and many other visitors who want to know about the organization. Usability of these websites will have different dimensions for different users. Hence broadly, measuring usability of website is a Multi criteria decision making problem (MCDM). Analytic hierarchy Process (AHP) approach has been considered a common solution to these problems. However, to handle uncertainty of the judgment Fuzzy Analytic Hierarchy Process (FAHP) is used. In this paper, different websites of an educational institute are compared and ranked on their usability criteria using FAHPItem Interference Estimation and Mitigation in Wireless Networks(University of Bahrain, 2015) Mustafa,S. AbdulkareemTo improve the resource utilization, the world of wireless communication network has seen suggestion and developing of new frameworks targeting an improved model of resource usage in wireless space by enabling cooperation and collaboration among possibly interfering wireless technologies in a dynamic and adaptive fashion. An important element of the cooperative framework is the discovery and learning process. The optimization mechanisms the framework will become to support strongly depend on the scope of information and observability of the system. An important part of this information is the effect of wireless networks on each other which is called the “inter-network interference” information. However, there are doubts in the research community on the efficacy or/and correctness of existing interference model for wireless networks. In this paper, the coexistence performance of wireless networks is analyzed in terms of throughput and packet reception ratio. It has been found that while SINR-based interference model necessities including other factors as the interferer's traffic rate, radio design etc. to be more realistic. The process of estimating this relationship is an expensive process and the question has been asked in this project is weather the framework should attempt to gather this information?Item SAAT: A Manual Annotation Tool for the Arabic Content Authoring(University of Bahrain, 2015) El-ghobashy,Ahmed N.; Attiya,Gamal M.; Kelash,Hamdy M.The Semantic Web (SW) approach actually founded by the actual mass of metadata availability and the representation of data with a proper knowledge. In order to achieve this approach it is necessary to generate metadata that is specific, easy to understand, structured and well defined. Up to now semantic annotation (SA) of a Web document is the effective way to make the SW vision a reality. This paper introduces proof of concept and two case studies of a manual Arabic annotation tool called SAAT that is used for embedding rich metadata within Arabic Web documents to markup the Web pages toward the enrichment process of the Arabic content. This tool is created using the JavaScript and PHP programming language to add Resource Description Framework in Attributes or RDFa metadata for Web pages. The RDFa will make the Arabic Web pages content more structured and machine processable. By using the SAAT tool, we hope to contribute toward the vision of the SW and open the field for Arabic Semantic Web research.Item A Complete Verification of a Full Search Motion Estimation Engine(University of Bahrain, 2015) Ismail,YasserA Full Search Motion Estimation architecture design is proposed and fully elaborated and tested in this paper. The proposed Motion Estimation architecture smartly reuses the data fetched from the main memory to be used in the search area. This allows using less memory I/O bandwidth. The proposed architecture guarantees a full utilization of all resources and not to have any stall at all during the Motion Estimation process. The proposed architecture guarantees high speed by performing the Motion Estimation process in adequate number of clock cycles. Additionally, high video quality is obtained using the proposed architecture. Both of the high speed and the high video quality are achieved by using an efficient algorithm to load the search area into a local memory. The local memory efficiently loads the processing array with the required search area and achieving two data reuse levels. We concentrate on elaborating and functionally testing the whole Motion Estimation architecture using VHDL verification language and provide a proof for the high accuracy of the designed architecture. The design of the local memory is implemented using only registers and a simple counter. This simplifies the design by avoiding the use of complicated addressing to write or read into/from the local memory. The proposed architecture has a regular data flow which leads to a simple VLSI implementation. The proposed architecture is flexible and can be used for low and high definition video sequences. Due to the high speed of the proposed architecture, it can be used for many real time video applications such as video phones, video conference, and HDTV broad casting.Item Reliability Modeling of a Cluster Based Distributed Mobile Ad-hoc Network(University of Bahrain, 2015) Choudhary,Anil; Roy,O.P; Tuithung,TModelling of a mobile ad-hoc network is a simplest way to represent real life networks for reliability and performance analysis. In this paper, an effort is made to develop a model of ad-hoc network cluster for evaluation of reliability. This model is based on Continuous-Time Markov Chain (CTMC). A mobile ad-hoc network model is especially useful to understand the practical implications and limitations of real world problems. A Cluster based approach is desirable for a large-scale multi-hop Mobile Ad-hoc Networks (MANET) in many future applications. The network models, mobility models and simulators for MANETs are reviewed by identifying their current limitations and future trends. Markov model is being used to solve dynamic system such as MANET. It is a mathematical system consisting of finite number of possible states that undergoes transition from one state to another state. In this paper, we also discuss how Markov�s model is used for estimating the reliability of a distributed ad-hoc network cluster using available tools. This paper also uses simulation scenarios and discusses simulation model design for reliability and performance evaluation of Ad-Hoc network.