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        1 - Design of Secure Communication System by Use of Synchronization of Chaotic Systems
        Mohammad nikkhoo masoud shafiee koorosh kiani
        In this paper, the concept of secure synchronization of chaotic systems using adaptive and robust techniques , has been discussed and then a new secure communication scheme, based on secure synchronization of a general class of chaotic systems called Generalized Lorenz More
        In this paper, the concept of secure synchronization of chaotic systems using adaptive and robust techniques , has been discussed and then a new secure communication scheme, based on secure synchronization of a general class of chaotic systems called Generalized Lorenz System, are presented. This communication scheme is combination of conventional cryptographic methods and chaotic modulation method. Analytical and simulation results using sine and voice signal and with unknown constant propagation delay between transmitter and receiver , have been presented. Also, robustness of this scheme against Gaussian channel noise with variance of , and security analysis of this communication system from brute-force viewpoint has been evaluated. By using this communication scheme, the very great key length has been obtained. Manuscript profile
      • Open Access Article

        2 - Polar Diagram of Points with Moving Pole
        Bahram Sadeghi Bigham fateme rabani
        Polar diagram is a generalization of Voronoi diagram in which the angle is used as the metric. This Problem has many applications in visibility, image Processing, telecommunication, antenna, and Path Planning Problems. In recent years two kinds of Polar diagram have bee More
        Polar diagram is a generalization of Voronoi diagram in which the angle is used as the metric. This Problem has many applications in visibility, image Processing, telecommunication, antenna, and Path Planning Problems. In recent years two kinds of Polar diagram have been proposed and appropriate algorithm have been Presented for some types of sites. Also, some algorithms has presented for kinetic data and dynamic states. In this Paper, it is assumed that the Pole is moving and an algorithm is presented that updates near Pole Polar diagram of sites with moving pole efficiently and in a sub linear time. In this approach, the Preprocessing time is 〖O(n^4 log〗_2⁡〖n)〗 and updating time for diagram with each successive movement is 〖 O(log〗_2⁡〖n +k)〗 that k is the number of sites in region T which its site’s regions may be changed Manuscript profile
      • Open Access Article

        3 - Increasing the lifetime of underwater acoustic sensor networks by optimal relay node placement
        zahra mihamadi mohadeseh soleimanpour daryush avasimoghaddam Siamak Talebi
        Underwater acoustic sensor networks (UASNs) have gained growing importance due to their desirable features and wide spread practical applications in many communication fields. Due to the high cost of underwater sensor nodes as well as implementation complexity, increasi More
        Underwater acoustic sensor networks (UASNs) have gained growing importance due to their desirable features and wide spread practical applications in many communication fields. Due to the high cost of underwater sensor nodes as well as implementation complexity, increasing the lifetime of UASNs is an important issue. Although relay nodes have an important role in reducing the transmission distance and energy consumption. But the efficient RNP (Relay Node Placement) to avoid the critical sensor nodes' elimination is the main problem, i.e., to preserve the connected network. For this aim this paper presents an innovative solution called an Efficient Relay node Setting (ERS) algorithm, which involves formulating the Relay Node Placement (RNP) as a non-convex optimization problem. Actually, due to the Difference Convex (DC) constraints the proposed RNP problem is a non-convex problem and finding an optimal solution is complicated. However, a novel transformation can be applied to DC constraints which converts the problem into its convex programming equivalent. Application of the convex programming offers the advantage of readily computing a global optimal solution. Simulation results confirm the superiority of the proposed scheme over the competing RA method in terms of network lifetime and efficiency. Manuscript profile
      • Open Access Article

        4 - Energy procurement of a cellular base station in independent microgrids with electric vehicles and renewable energy sources: Mixed-integer nonlinear programming model
        Reza Bahri saeed zeynali
        The cellular base stations are communication devices that ensure the connection in the world. Nevertheless, they are usually installed in remote places. This paper, studied the energy procurement of a cellular base stations in an independent microgrid with a hydrogen-ba More
        The cellular base stations are communication devices that ensure the connection in the world. Nevertheless, they are usually installed in remote places. This paper, studied the energy procurement of a cellular base stations in an independent microgrid with a hydrogen-based energy storage system, photovoltaic (PV) system, electric vehicles and a diesel generator. A new mixed-integer nonlinear programming model was used to deal with nonlinearities of the system components. The paper studied different uncertainties, such as the connection rate in cellular base stations, the driver of the electric vehicle, and PV generation, using stochastic programming method. The potency of the proposed method was studied in different case studies. The results prove that smart electric vehicle chargers reduce the risks and also cost/emission objective functions. The usage of this model can reduce the emissions as much as 18.60%. Manuscript profile