• Journal of the Korean Institute of Gas
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• v.7 no.3 s.20
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• pp.24-31
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• 2003

To operate process plant safely and economically, process monitoring is very important. There are a great number of data acquired through distributed control system and process information system. Fault monitoring is the task with difficulties owing to not only the huge amount of data, but also nonlinearity of chemical processes. In this research, the program, REFA, based on PCA and functional link associative neural network has developed. REFA has better learning capabilities, generalization abilities, and shorter learning time than existing neural network programs. In this work its usefulness has proven by application to Tennessee Eastman process.

• Proceedings of the Korea Society for Simulation Conference
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• 2004.05a
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• pp.20-24
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• 2004

광범위한 네트워크의 연결과 이를 이용하는 조직이나 개인의 증가로 인터넷은 정보를 교환하고 거래를 수행하는 주요한 수단이 된 반면에 해커나 바이러스의 침입 또한 증가하여 공격에 쉽게 노출되어있다. 이러한 보안상의 문제점을 해결하기 위하여 컴퓨터나 네트워크 시스템의 활동을 감시할 수 있는 침입 탐지 시스템(IDS)과 같은 보안 요소를 도입하였으며, 탐지에 대한 성능을 향상시키기 위하여 네트워크를 기반으로 하는 다중 침입 탐지 시스템을 응용하여 네트워크에 분산된 에이전트들 중에서 발생된 침입에 알맞은 에이전트를 선택하도록 하여 침입 탐지를 효과적으로 할 수 있게 하였다. 본 연구에서는 보안 시스템의 연동을 위하여 계약망 프로토콜을 적용하였다. 계약망 프로토콜은 분산된 에이전트들 중에서 입찰과정을 통하여 최상의 에이전트를 선택하는데 이때, 에이전트를 선택하는 과정에 있어서 퍼지 규칙 기반 시스템을 적용한 퍼지 컨트롤러를 설계하여 시뮬레이션 한다.

• Nuclear industry
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• v.16 no.8 s.162
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• pp.45-52
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• 1996

원전의 방사능 누출은 물론, 전국의 환경 방사선이나 기상 등을 수시로 종합 감시하여 즉각적으로 대응하는 방사능 방재 전산망이 본격 가동되었다. 과학기술처는 7월 31일 과천 청사 방사선 비상대책실에서 원전 사고 등 비상시에 방사능 누출 현황 등을 컴퓨터 화면으로 한눈에 보고 대응책을 마련할 수 있는 방사능방재대책 기술지원전산망 가동식을 가졌다. 이 전산망은 $\ulcorner$방사선 영향 평가 및 예측 전산화 시스템(CARE)$\lrcorner$을 중심으로 서울 등 전국 20개 지역의 환경방사선량을 표시해주는 환경방사능 감시망과 기상자료 수집망이 하나로 연결된 컴퓨터 통신망이다. 이의 운영 현황을 들어본다.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2002.06a
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• pp.80-88
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• 2002

휴대용 컴퓨터의 보급이 확산됨에 따라 이들을 장소에 상관없이 컴퓨터망에 연결시키는 수단으로 무선 LAN의 사용이 확산되고 있으나 무선 LAN 서비스는 전파라는 무선매체를 사용함으로써 정보도용의 가능성이 높으며 감시도 어렵다는 특징을 가지므로 정보보호가 요구된다. 본 논문에서는 IEEE 802.11 표준안 및 IEEE 802.lleS 초안에서 제시하는 무선 LAN의 정보보호기술인 ESN, WEP, AES 및 SMIB에 관하여 기술한다.

• Journal of The Korean Association of Information Education
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• v.5 no.3
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• pp.374-379
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• 2001

Recently, R & D about Network Monitoring System is needed to be effective network management and to improve computer education. In this work, we propose a real time network monitoring system named NetCop to improve network management and effective use. This system is designed to show any screen to one or more students in interactive learning environment. The system also provides useful functions such as monitoring students' PCs and chat. In additions, our NetCop can provide more effective learning process to students. Finally, we expect that our system can achieve high network performance and provide high educational quality to managers.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.05a
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• pp.477-480
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• 2008

In this paper, we design the TCP-Light protocol for directly connecting a sensor network with Internet. When we are monitoring the data and controlling of the sensor node, the sensor network must be connected to Internet. But TCP in wireless networks has a number of performance problems which is high bit-error rates and a hardware constraint. Moreover, the end-to-end acknowledgment and retransmission scheme employed by TCP causes expensive retransmissions along every hop of the path between the sender and the receiver. This paper introduces The TCP-Light protocol which increases TCP performance in wireless sensor networks, decreases the number of end-to-end retransmissions and decreases memory consumption.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.2
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• pp.391-400
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• 2008

There has been increasing interest in developing Structure Health Monitoring(SHM) system based on wireless sensor network(WSN) due to recent advancement in sensor network technologies. SHM is the continuous monitoring of the condition such a acceleration or load of a structure. The SHM system works, which measure key structure parameters systematically, provide information in evaluation of structure integrity, durability and reliability. Currently SHM system collects data via analog sensor and then sends to analysis application through the wired network. The wire system support high accuracy, but suffers the disadvantages in installation costs, complexity of connection and loss of line. It's also difficult to add new sensor nodes. We design and implement the SHM system based on WSN technology to solve those problems.

• Spatial Information Research
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• v.18 no.2
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• pp.1-12
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• 2010

At present, monitoring programmes for green network have been mainly based on field sampling, which relies on attributes of an area at one point in time, reflecting an emphasis on the small number of in-situ data. One of the major disadvantages of traditional field monitoring is that it is costly, laborious and time consuming due to the large number of samples required. The aim of this research was to evaluate green network based on pixel of Landsat TM satellite image. An empirical study for a case study site was conducted to demonstrate how a standard remote sensing technology can be used to assist in monitoring the green network based on pixel. The pixel-based analysis made it possible to identify area-wide patterns of green network subject to many different type of artificial structures, which cannot be acquired by traditional field sampling. It was demonstrated that the degradation trends of green network could be used effectively as an indicator to restrict further development of the sites since the quantitative data generated from remote sensing can present area-wide visual evidences by permanent record. It is anticipated that this research output could be used as a valuable reference to support more scientific and objective decision-making in monitoring green network.

• Journal of the Korean Institute of Gas
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• v.28 no.2
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• pp.38-46
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• 2024

The city gas pipeline network is characterized by being widely distributed and hierarchically connected in a complex manner over a wide area. In order to monitor the status of the widely distributed network pressures with high precision, Multi-block PCA(MBPCA) is recommended. However, while MBPCA has excellent performance in identifying faulty sensors as the number of sensors increases, the fault detection performance deteriorates, and also there is a problem that the model needs to be updated entirely even if minor changes occur. In this study, we developed fault detectability index and fault identificability index to determine the effectiveness of MBPCA application block by block. Based on these indices, we distinguished MBPCA and PCA blocks and developed a fault detection and diagnostic system for the city gas pipeline network of Haean Energy Co., Ltd., and were able to solve the problems that arise when there are many sensors.

• Proceedings of the Korean Information Science Society Conference
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• 2001.10a
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• pp.454-456
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• 2001

본 논문에서는 분산된 Host들의 실시간 모니터링 및 원격지 Host의 제어, 관리를 수행함으로써 네트웍 활용의 효율을 높이기 위한 분산 네트웍 환경에서 실시간 모니터링시스템(NetCop)을 구현 연구하였다. 이 시스템은 분산된 Host들의 효율적인 네트웍 활용 및 관리를 위해 그것의 성능을 저해하는 사용자의 유무를 체크하고 경고 메시지 및 허용되지 않은 프로그램의 실행 방지 등 사용자의 편리를 위해 제공.비치된 컴퓨터나 어떤 형태로든지 네트웍 망에 연결된 단말기의 사용범위를 실시간으로 감시, 제어 및 관리할 수 있는 기능을 제공한다. 또한 그것으로 인해 네트웍 사용의 낭비를 막을 수 있고 더 나아가 네트웍의 전체적인 성능을 높일 수 있으며 사용자에게 더 효율적인 사용 환경을 제공할 수 있는 장점이 있다.