• Journal of the Korean Institute of Intelligent Systems
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• v.17 no.5
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• pp.712-717
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• 2007

Using home network system including home server, home service robot, a variety of device, it is generally known that application of Multi Agent System for performing variously distributed process that can be occur in home environment, is efficient method. In this system, it is intelligent service robot that a key of human interface and physical service offer Therefore, using application of established multi agent system, we can defined Multi Agent Robot System. In 'open' home environment, between all agent data interaction and cooperation are needed for Multi Agent System offer to user that more efficient service. For this, we focus our attention on define as agent that can autonomic drive and offer to user that physical service robots and, design, suggest the simulator can display that between robot agents communication or between other agents, like home server, and robot agents communication information to user interface.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.12B
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• pp.1044-1048
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• 2006

This paper proposes a FTOG(Fault-Tolerant Object Group)-based recovery services through replicated objects. In the distributed system, the fault of the object component may cause an entire system failure, evidently raising the service breakdowns. Therefore, this paper proposes recovery services with the replicated objects in case of fault occurrences. Moreover, applying the FTOG model to a virtual home network simulation, we verify the consistency maintenance and the service reliability of the proposed model.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.1B
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• pp.74-85
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• 2009

We propose an Agent-based Fault Tolerant Object Group model based on the agent technology and FTOG model with replication mechanism for effective object management and fault recovery. We define the five kind of agents - internal processing agent, registration agent, state handling agent, user interface agent, and service agent - that extend the functions of the FTOG model. The roles of the agents in the proposed model are to reduce the remote interactions between distributed objects and provide more effective service execution. To verify the effectiveness of the proposed model, we implemented the Intelligent Home Network Simulator (IHNS) which virtually provides general home networking services. Through the simulations, it is validated that the proposed model decreases the interactions of the object components and supports the effective fault recovery, while providing more stable and reliable services.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.2
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• pp.102-110
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• 2012

ZigBee networks developed for low power and short range communication are being used as home network solution for ubiquitous computing. However, as smart phones and tablet PCs have been widely used, WLANs which use same frequency with ZigBee networks have been increasingly used. Therefore, radio frequency interference causes many problems. To solve radio frequency interference problem among ZigBee networks and WLANs, many researches focus on designing interference minimization schemes in ZigBee networks. However, existing schemes have problems that have waste of resource for detecting interference, and have unnecessary time to avoid interference. In this paper, we propose an interference minimization scheme to solve radio frequency interference in ZigBee networks. The proposed scheme detects interference using ACK mechanism to reduce waste of resource, and avoids interference using table driven channel hopping scheme which is faster than existed schemes. The performance of proposed interference minimization scheme is evaluated by using OPNET simulator. Through the simulation result, we prove that proposed scheme has faster channel hopping than existing schemes.