• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.15 no.6
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• pp.73-81
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• 2001

This study uses the distributed parameter systems resented by the spatial discretization technique. In this paper, the distributed parameter systems are converted into lumped parameter systems, End fast Walsh transform and the Picard's iteration method are allied to analysis the state of the systems. This thesis presents a new algorithm which usefully exercises the optimal contro1 in the distributed parameter systems. In exercising the optimal control of the distributed parameter systems, the excellent consequences are found without using the existing decentralized contro1 or hierarchical control method. This study can be applied to the linear time-varying systems and the non-linear systems. Farther researches are required to solve the problems of convergence in case of the numerous applicable intervals. The simulation proves the effectiveness of the proposed algorithm.

• Proceedings of the IEEK Conference
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• 2002.07a
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• pp.309-312
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• 2002

Advances in networking infrastructure have led to the development of a new type of "computational grid" infrastructure that provides predictable, consistent and uniform access to geographically distributed resources such as computers, data repositories, scientific instruments, and advanced display devices Such Grid environments are being used to construct sophisticated, performance-sensitive applications in such areas as dynamic, distributed real-time applications. In this paper, we propose a toolset for designing distributed real-time systems based on computational grid. The toolset is based on a new methodology and integrates the models that methodology Proposed for designing real-time systems.

• Journal of Institute of Control, Robotics and Systems
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• v.20 no.11
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• pp.1131-1135
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• 2014

This paper proposes the enhanced faulty node detection scheme with hybrid algorithm using Markov-chain model on BCH (Bose-Chaudhuri-Hocquenghem) code in naval distributed control networked systems. The probabilistic model-driven approach, on Markov-chain model, in this paper uses the faulty weighting interval factors, which are based on the BCH code. In this scheme, the master node examines each slave-nodes continuously using three defined states : Good, Warning, Bad-state. These states change using the probabilistic calculation method. This method can improve the performance of detecting the faulty state node more efficiently. Simulation results show that the proposed method can improve the accuracy in faulty node detection scheme for real-time naval distributed control networked systems.

• International Journal of Reliability and Applications
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• v.1 no.2
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• pp.105-113
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• 2000

This paper discusses some problems of the TMN-based architecture of integrated network management systems and presents a CORBA-based architecture of distributed network management system with reliability, which maintains location transparency of distributed managed objects and provides an interoperability among heterogeneous networks and systems. In this paper, the proposed distributed management system model has been applied to the TMN based management systems and then considered for qualitative evaluation of system performance. Two different types of implementation models have been proposed: one is a system using a CORBA gateway and the other is a pure CORBA system, which maps all managed objects into CORBA objects. The characteristics of two system model have been compared in the respect of system implementation

• Journal of the Korea Society of Computer and Information
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• v.21 no.8
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• pp.41-48
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• 2016

In this paper, we propose an election protocol based on mobile ad-hoc network. In distributed systems, a group of computer should continue to do cooperation in order to finish some jobs. In such a system, an election protocol is especially practical and important elements to provide processes in a group with a consistent common knowledge about the membership of the group. Whenever a membership change occurs, processes should agree on which of them should do to accomplish an unfinished job or begins a new job. The problem of electing a leader is very same with the agreeing common predicate in a distributed system such as the consensus problem. Based on the termination detection protocol that is traditional one in asynchronous distributed systems, we present the new election protocol in distributed systems that are based on MANET, i.e. mobile ad hoc network.

• International Journal of Contents
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• v.5 no.3
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• pp.79-85
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• 2009

Emergent requests or urgent information among enterprises require their intimate collaboration in B2B EC (electronic commerce). This paper analyzes the needs of intimate cooperation of distributed EC systems in terms of business contracts and presents an active rule-based methodology of close cooperation among EC systems and an active rule component to support it. Since the rule component provides high level rule patterns and event-based immediate processing, system administrators and programmers can easily program and maintain intimate cooperation of distributed EC systems independently to the application logic. The proposed active rule component facilitates HTTP protocol. Its prototype is implemented in B2B EC environment and evaluated using basic trigger facility of a commercial DBMS.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.11
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• pp.1558-1561
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• 2020

In this paper, we propose a blockchain scheme to enhance fault tolerance in distributed storage blockchain systems. Traditional blockchain systems suffer from ever-increasing storage cost. To overcome this problem, distributed storage blockchain techniques have been proposed. Distributed storage blockchain schemes effectively reduce the storage cost, but there are still limitations in reducing recovery cost and fault tolerance. The proposed approach recovers multiple errors within a group by utilizing locally repairable codes with availability. This improves the fault tolerance of the blockchain systems. Simulation results show that the proposed scheme enhances the fault tolerance while minimizing storage cost and recovery cost compared to other state-of-art schemes.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2003.10a
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• pp.113-117
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• 2003

In the industrial field nowadays the information that needs to be handled arc increasing and requires faster speed in contrast with PLC(Programmable Logic Controller) or DCS(Distributed Control System) based control systems these days. The work environment these days are mostly based on PC, so the control systems are wanted in PC. At Fieldbus used automated systems performing distributed process control by PC performs and combines into one system in order to maximize the increase of productivity, lower the expense, planning constructing and maintaining the reliance of automation. These latest automation systems unites process, makes distributed control process able, and can control and supervise at remote PC.

• Structural Engineering and Mechanics
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• v.37 no.1
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• pp.17-37
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• 2011

This paper presents a new Internet-based computational framework for the realistic simulation of multi-scale response of structural systems. Two levels of parallel processing are involved in this frame work: multiple local distributed computing environments connected by the Internet to form a cluster-to-cluster distributed computing environment. To utilize such a computing environment for a realistic simulation, the simulation task of a structural system has been separated into a simulation of a simplified global model in association with several detailed component models using various scales. These related multi-scale simulation tasks are distributed amongst clusters and connected to form a multi-level hierarchy. The Internet is used to coordinate geographically distributed simulation tasks. This paper also presents the development of a software framework that can support the multi-level hierarchical simulation approach, in a cluster-to-cluster distributed computing environment. The architectural design of the program also allows the integration of several multi-scale models to be clients and servers under a single platform. Such integration can combine geographically distributed computing resources to produce realistic simulations of structural systems.

• Journal of Korea Multimedia Society
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• v.18 no.4
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• pp.452-459
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• 2015

Three synchronization issues, i.e., phase, frequency, and symbol time, have to be properly controlled to achieve distributed beamforming gain. In this paper, the impacts of synchronization errors in distributed beamforming are analyzed for both single-carrier and OFDM systems. When the channel is constant over a symbol duration, the performance degradation due to phase offset is the same for both single-carrier and OFDM systems. For symbol timing offset in OFDM systems, high frequency subcarriers are more susceptible as compared to low frequency ones. Frequency offset is critical in OFDM systems since it leads to interference from the other subcarriers as well as power loss in the desired signal.