• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.112-117
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• 1992

The Real-time Distributed Control Systems(RDCS) consist of several distributed control processes which share a network medium to exchange their data. Performance of feedback control loops in the RDCS is subject to the network-induced delays from sensor to controller and from controller to actuator. The network-induced delays are directly dependent upon the data sampling times of the control components which share a network medium. In this study, a scheduling algorithm of determining data sampling times is developed using the window concept, where the sampling data from the control components dynamically share a limited number of windows.

• 한국정보시스템학회지:정보시스템연구
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• 제4권
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• pp.85-104
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• 1995

In a loosely-coupled distributed database server system, a server failure and/or a communication failure can be masked by a resiliency mechanism. Recognizing that a distributed transaction executes at several servers during its lifetime, we propose a resiliency mechanism which allows continuous transaction processing in distributed database server systems in the presence of a server failure. The resiliency mechanism for transaction processing is achieved by keeping redundant information using a primary/backup approach. The purpose of this paper is to analyze the performance improvement opportunities with the resiliency mechanism and to present the design of the proposed system.

• 정보처리학회논문지D
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• 제13D권1호
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• pp.139-146
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• 2006

본 논문에서는 분산 트랜잭션 워크플로우 모니터링 시스템의 설계 및 구현에 관하여 기술한다. 워크플로우 인스턴스들의 실행 상태 관리를 주요 목적으로 하는 전통적인 워크플로우 시스템의 모니터링 기능은 워크플로우의 초대형화와 트랜잭션화를 특징으로 하는 분산형 트랜잭션 워크플로우 시스템에서는 워크플로우의 처리 상태 관리뿐만 아니라 구조적인 정보의 수집, 통계 정보 제공, 사용자들의 처리 상태 정보 등과 같은 다양한 부가적인 정보 처리 및 관리 기능을 제공하는 분산형 모니터링 서비스를 필요로 한다. 본 논문에서는 이러한 분산형 트랜잭션 워크플로우 시스템에서 필수적으로 요구되는 새로운 워크플로우 모니터링의 특징을 확장 정의하고, 이를 지원하는 점 기반의 분산 트랜잭션 워크플로우 모니터링 시스템의 상세 설계 및 이의 구현 방안을 소개한다.

• 디지털산업정보학회논문지
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• 제14권3호
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• pp.39-44
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• 2018

Communication in real-time distributed system should have high reliability. To develop group communication Protocol with high reliability, potential fault should be known and when fault occurs, it should be detected and a necessary action should be taken. Existing detection method by Ack and Time-out is not proper for real time system due to load to Ack which is not received. Therefore, group communication messages from real-time distributed processing systems should be communicated to all receiving processors or ignored by the message itself. This paper can make be sure of transmission of reliable message and deadline by suggesting and experimenting fault detection technique applicable in the real time distributed system based on ring, and analyzing its results. The experiment showed that the shorter the cycle of the heartbeat signal, the shorter the time to propagate the fault detection, which is the time for other nodes to detect the failure of the node.

• 한국항만학회지
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• 제13권2호
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• pp.289-302
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• 1999

As the size and complexity of network increase Distributed System Management (DSM) will be significant issue within information network in order to increase the high reliability and to improve the flexibility of network management. The OSI management model has several problems. The key problems are that it does not fully address the problem of how to develop communication protocol in support of DSM and how to classify the management connection criteria. In this paper to solve first problem described above this paper propose the connectionless CMIP to accomplish for effectively managing the distributed management managing systems to handle the dynamic informations. To work out second problem we introduce the connection criteria in the hierarchy of management system and finally evaluate the efficiency of a suggested protocol during cooperative negotiation among the managing system.

• 제어로봇시스템학회논문지
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• 제13권6호
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• pp.596-602
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• 2007

Recently, many ECUs(Electronic Control Units) have been used to enhance the vehicle safety, which leads to a distributed real-time control system. The distributed real-time control system requires to reduce the network delay for dependable real-time performance. There are two different paradigms by which a network protocol operates: event-triggered and time-triggered. This paper focuses on implementation of a time-triggered protocol. i.e. TTP/C(Time-Triggered Protocol/class C). This paper presents a design method of TTP control network and performance evaluation of distributed real-time control system using TTP protocol.

• 산업공학
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• 제16권1호
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• pp.1-7
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• 2003

Today's manufacturing enterprise relies heavily on the collaboration and coordination among the distributed manufacturing systems. The effective exchange of the various manufacturing information among the distributed organizations contributes a great deal to their productivity. An Internet-Based Manufacturing Desk is developed for the production of the press dies in the automobile industry in order to solve the manufacturing problems among the distributed organizations, to maintain their smooth and immediate information flow, and to increase their productivity finally. The CBR(Case-Based Reasoning) method is applied to achieve those effects. Using the method, the solutions and methods of the predetermined case-bases are retrieved and applied to solve a newly introduced problem. The developed system is implemented and applied successfully.

• Asia pacific journal of information systems
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• 제7권3호
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• pp.23-37
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• 1997

Although numerous models and solution algorithms to design efficient distributed databases have been developed, very few have been validated for their effectiveness. In this paper, we develop a simulation system which can be used to analyze and validate the average response time of distributed database designs. Our simulation system models comprehensive query processing strategies such as semijoin as well as a concurrency control mechanism We analyze and validate an average response time distributed database design model using our simulation system.

• International Journal of Contents
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• 제3권1호
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• pp.34-38
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• 2007

Load redistribution is a critical resource in computer system. In sender-initiated load redistribution algorithms, the sender continues to send unnecessary request messages for load transfer until a receiver is found while the system load is heavy. These unnecessary request messages result in inefficient communications, low CPU utilization, and low system throughput in distributed systems. To solve these problems, we propose a genetic algorithm based approach for improved sender-initiated load redistribution in distributed systems. Compared with the conventional sender-initiated algorithms, the proposed algorithm decreases the response time and task processing time.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.88.1-88
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• 2001

The paper describes a new approach to the organization of an artificial brain for mobile multi-robot systems, where individual robots are not considered as independent entities, but rather forming together a universal parallel and distributed machine capable of processing both information and physical matter in distributed worlds. This spatial machine, operating without any central control, is driven on top by distributed mission scenarios in WAVE-WP language. The scenarios can be written on a variety of levels, and any mixture of them, supporting the needed system flexibility and freedom ...