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Advances in Computer Research - Volume:4 Issue: 4, Autumn 2013

Journal of Advances in Computer Research
Volume:4 Issue: 4, Autumn 2013

  • تاریخ انتشار: 1392/09/20
  • تعداد عناوین: 8
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  • Sedigheh Navaezadeh, Iman Zangeneh, Mehnoosh Vahebi Pages 1-7
    Every year, with regard to rapid development of data, Grid computing that is a kind of distributed computing system is that it has attracted the attention of most people and considerably taken into account. Computing that cannot be done by huge computers can be performed by Grid computing. If load balance is used, efficiency will increase in Grid. Resources have an important and effective role in Grid efficiency. When resources are available and accessible, the access time and efficiency will improve. In this paper, swarm intelligence algorithm has been used and applied in Grid in order to provide load balance. Since Grid environment is a dynamic environment, glowworm algorithm is used to provide load balance in sites. The results of algorithm simulation presented by Matlab software show that, by using this algorithm, efficiency as well as reliability will increase in Grid environment. Also, this algorithm has been compared with two other algorithms in this field.
    Keywords: Swarm Intelligence Algorithm, Glowworm Algorithm, PSO, LA(learning automat), Grid, Load balance
  • Pedram Hajipour * Pages 9-20
    In this paper, new features of satellite configuration, Such as IP network based infrastructure and separated signaling and media are considered to propose a variety of satellite configurations in different orbits. Because of their different altitude in space such as Low Earth Orbit(LEO) and Geostationary orbit (GEO). A test bed used to test call setup delay in a one space link to process the Media Gateway Control protocol calls was reviewed. Furthermore, three different call flows is presented by M/M/1 queuing model that can be used for deploying and evaluating Next Generation Network for satellite configurations. These call flows help to verify Media Gateway Controller protocol and also allow testing and evaluating in various call set up delay time for different satellite configurations . In these simulations, a satellite is a Media Gateway Controller node for receiving and transmitting IP messages in a Space link and a ground stations is Media Gateway node.
    Keywords: MEGACO, Queuing Model, SLSA, FLSA, HLSA
  • Meissam Khatibi Nia, Ali Akbar Gharaveisi Pages 21-36
    Controller design and optimization problems, with more than one objective, are referred as multiple objectives or multiple attributed problems. In this paper, a novel method is proposed for designing optimum PID controller that is called genetic multiple attributed decision making method (GMADM). This method is newer than the previous methods and in this paper some options are considered that have not been considered in previous paper for simplicity. The proposed PID controller is applied on the automatic voltage regulator (AVR).An automatic voltage regulator system is the main part of a generator because this system keeps the output voltage in constant level. The simulation results of automatic voltage regulator system are compared with conventional multiobjective algorithm, known as multiobjective genetic algorithm (MOGA).The simulation results of automatic voltage regulator system show that GMADM method is better than MOGA and number of optimum solutions of the proposed method is greater than the other one.
    Keywords: Genetic multiple attributed decision making, Entropy, TOPSIS, Pareto, Multiobjective genetic, Automatic voltage regulator
  • Homayun Motameni, Mohammad Vahidpour, Babak Shirazi, Behnam Barzegar Pages 37-50
    With recent developments in communication technologies, it is possible to access information any time and in any place; however, mobile environments bring forward certain requirements and exclusive challenges including low connection speeds and bandwidth limitations. Thus, we need to consider mobile limitations when using web services. Providing services and limited resource allocation to users and at the same time maintaining performance and quality is a challenging and somewhat difficult task. In this paper, an architecture is introduced and described for showing the mobile agent request process in mobile environments. A mathematical model is introduced for performance analysis; however, the main challenge is the state space explosion in Markov Chain, which complicates the relations. Hence, a model has been suggested using Stochastic Colored Petri Nets that encompasses two sections. A case study performed on mobile networks and the results of implementation are compared with the proposed method. Therefore, by using the proposed method, it is easy to analyze the effect of network limitations and connection methods on performance.
    Keywords: evaluation, Mobile Environment, Petri Nets, Markov Chain
  • Yazdan Jamshidi, Hossein Nezamabadi, Pour Pages 51-60
    As networking and communication technology becomes more widespread, thequantity and impact of system attackers have been increased rapidly. Themethodology of intrusion detection (IDS) is generally classified into two broadcategories according to the detection approaches: misuse detection and anomalydetection. In misuse detection approach, abnormal system behavior is defined atfirst, and then any other behavior is defined as normal behavior. The main goal ofthe anomaly detection approach is to construct a model representing normalactivities. Then, any deviation from this model can be considered as an anomaly,and recognized to be an attack. Recently much more attention is paid to theapplication of lattice theory in different fields. In this work we propose a latticebased nearest neighbor classifier capable of distinguishing between badconnections, called attacks, and good normal connections. A new nonlinearvaluation function is introduced to tune the performance of the proposed model. Theperformance of the algorithm was evaluated by using KDD Cup 99 Data Set, thebenchmark dataset used by Intrusion detection Systems researchers. Simulationresults confirm the effectiveness of the proposed method.
    Keywords: Anomaly detection, Nearest Neighbor, Lattice Theory, Positive Valuation Function, KDD Cup 99
  • Time Slot Allocation Algorithm Based On TDMA Protocol In Wireless Sensor Networks
    Somayeh Rahmani, Ahmad Khademzadeh, Amir Masoud Eftekhari Moghadam Pages 61-71
    In recent years, many researchers have been done in the area of wireless sensor networks that has led to the variety of algorithms and methods for the collection andtransmission of environment information; but still many challenges faced by wireless sensor networks using methodologies are applied in various fields. Such as Media Access Control that due to the media being shared on these networks, there is a possibility of collision and data loss. Since the retransmission increases network latency and consequently reduces network energy, therefore various solutions have been proposed for media access control that their main purpose is media access control and prevention of collisions. Hence media access control protocols requirement, more and more felt. In this study, a free collision algorithm with the acceptable ability to media access channel is presented in which we have tried to reduce the number of time slots and increase the network throughput as much as possible.
    Keywords: Sensor Networks, Throughput, time slots, Media Access Control, Collision
  • Ad Hoc On-demand Non Overlapped Multipath Distance Vector Routing Protocol (AONOMDV)
    Mina Vajed Khiavi, Shahram Jamali, Sajjad Jahanbakhsh Gudakahriz Pages 73-81
    In this paper, we propose a scheme to improve existing Ad-Hoc On-Demand Distance Vector (AODV) routing protocol by discovering and maintaining multiple non-overlapped routes. Our routing protocol is a multipath version of AODV routing protocol that considers only the disjoint path. Due to non-overlapping among paths, when a link breaks in the network, only one of paths is expired. The presented routing protocol, called Ad hoc On-demand Non Overlapped Distance Vector (AONOMDV), is implemented by some modifications over AODV module in ns-2 simulator. Results of simulations show that AONOMDV has better performance in comparison with AODV and AOMDV in terms of the average end-to-end delay, the packet delivery ratio and the route discovery frequency.
    Keywords: AODV, Mobile Ad, hoc Networks, routing
  • Observer-Based Control for a Modified Duffing System Using Twisting Algorithm
    Milad Malekzadeh, Alireza Khosravi Pages 83-91
    This paper presents a new observer-based control scheme for a class of nonlinear systems. In the proposed method, nonlinear observer and twisting algorithm controller are employed to realize a sensor-less control strategy for complex systems which makes use of non measurable process information instead of installing as many sensors as possible. Due to lack of availability of the complex system states, controlling of them will be faced with undesirable performance. This deficiency can be solved with adding observer in the control strategy. In order to estimate unavailable states, an adaptive neural network observer is considered in the present article. This observer is tuned online and no exact information of the nonlinear function in the observed system is required. Also, to realize control purpose, 2nd order sliding mode controller called twisting algorithm is located in the close loop structure. This control strategy is implemented on the modified Duffing chaotic system and the simulation results confirm the capability of thismethod.
    Keywords: twisting algorithm, adaptive neural network observer, Modified Duffing system, Chaos