• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 춘계학술대회논문집
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• pp.778-781
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• 2008

The aim of this paper is to analyze the dynamic responses of pantograph-overhead contact line coupled system by using a condition monitoring system. The monitoring items are strain, vertical displacement and acceleration of a contact wire. Both strain and vertical displacement in the contact wire depends on uplift force and train velocity. Measurement of acceleration shows that the passage of the pantograph gives an impact force to a hard point on a contact wire.

• 한국전기전자재료학회논문지
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• 제22권3호
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• pp.218-221
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• 2009

This paper reports on measurement method for the fiber optic strain monitoring of overhead contact line systems of trains, We used FBG (Fiber Bragg Grating) sensors to measure the strain variation of overhead contact line. FBG sensors can sensitively measure the variation of strain and! or temperature by the shift wavelength of reflected wave according to the lattice variation during the measurement. FBG sensor were attached on the contact line and connected to the monitoring system with optical fibers. The monitering system with FBG sensors showed very good sensitivity to measuring strain variation and this system could be applied to the overhead contact line of KTX (Korea Train eXpress).

• 한국철도학회:학술대회논문집
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.1483-1487
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• 2006

In electric railway, image monitoring using high speed camera provides reliable, timely information of wear and geometry status, important in taking decisions for overhead contact wire maintenance. The contribution of this research is the development of a simple real-time monitoring system for use in measurement subsystem of contact wire and geometry of overhead contact wire in electric railway. The system has been consists of a high speed CMOS camera with resolution $1024{\times}1280$ pixels, line type laser source and PC-based image acquisition system with PCI Express slot. Vision acquisition software have been used in application programming interface for image acquisition, display, and storage with a frequency of sampling of 500 acquisitions per second.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.531-532
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• 2006

This paper presents the implementation of Real-time data acquisition system for dynamic characteristics of overhead contact wire in electric railway. The reconfigurable field-programmable gate array (FPGA) and LabVIEW graphical development tools have been used to Real-time monitoring system. The results from a field test show that the proposed technique and developed system can be practically applied to measure the assessment quantity or quantities on overhead contact lines for the online real-time process monitoring.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.1227-1230
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• 2008

This paper reports on measurement method for the fiber optic strain monitoring of overhead contact line systems of trains. We used fiber Bragg grating (FBG) sensors to measure the strain variation of overhead contact line. FBG sensors were attached on the contact line and connected to the monitering system with optical fibers. The monitering system with FBG sensors showed very good sensitivity to measuring strain variation and this system could be applied to the overhead contact line of KTX.

• 인터넷정보학회논문지
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• 제4권6호
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• pp.13-24
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• 2003

그리드 기술은 지리적으로 분산된 컴퓨팅 자원을 활용하기에 다양한 자원에 대한 정보를 관리하는 기술이 필요하며, 이는 자원 관리 시스템에서 자원을 모니터링하여 이루어진다. 자원 상태 정보가 실시간으로 변하여 주기적으로 모니터링을 해야 하므로 이에 따른 오버헤드가 예상된다. 본 논문에서는 CPU상태 변화 정도를 관찰하여 시스템 상태를 파악하고 이를 모니터링 주기에 적용시키고자 한다. 즉 그리드 환경의 중요한 요소인 자원의 상태를 고려하여 자율적으로 자원의 상태에 따른 모니터링 주기를 조절하는 시스템을 모델링 하였다. 자원의 CPU 상태를 관찰해 CPU의 상태 변화율에 따라 자원의 상태 변화를 파악하여 모니터링 주기를 조절함으로써 모니터링에 의한 오버헤드가 감소하였음을 실험을 통해 증명하였다.

• 전자공학회논문지CI
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• 제43권3호
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• pp.1-9
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• 2006

SNMP는 네트워크 장비들의 관리를 위한 표준 프로토콜이지만 요즘의 대부분의 컴퓨터 시스템들은 SNMP 에이전트로서의 기능을 보유하고 있다. 본 논문에서는 임베디드 시스템을 위한 저부하의 SNMP 라이브러리를 개발하고, 이를 활용하여 많은 수의 시스템들을 일괄적으로 모니터링하기 위한 소프트웨어를 구현하였다. 모니터링 시스템은 모니터링 서버, SNMP 에이전트들, 및 클라이언트 프로그램으로 구성된다. 모니터링 서버는 모니터링 대상 시스템에서 실행되는 SNMP 에이전트들로부터 상태정보들을 수집하고 요약 정보를 클라이언트 프로그램에게 전달한다. 클라이언트 프로그램은 Java를 활용한 독자적인 프로그램과 웹 기반의 프로그램의 두 가지 버전을 구현하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.543-544
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• 2006

This paper describes a simple real-time monitoring system for use in measurement subsystem of contact wire and geometry of overhead contact wire in electric railway. The system has been consists of a high speed CMOS camera with resolution $1024\;{\times}\;1280$ pixels, line type laser source with a power equal to 300 mW, and PC-based image acquisition system with PCI Express slot. National instrument LabVIEW (8.0) and vision acquisition software have been used in application programming interface for image acquisition, display, and storage with a frequency of sampling of 500 acquisitions per second.

• Journal of Information Technology Applications and Management
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• 제12권4호
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• pp.123-131
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• 2005

Since most of the conventional web servers have been designed to Provide the general purpose and user's convenience as the primary goal, there is an overhead to apply them to the embedded system for remote monitoring and controlling the operation status of the Internet appliance. To cope with this overhead, an embedded Linux web server Is suggested in this paper The basic concept is to provide miniaturization and extendability by simplifying the requirements of web server as the services to the requests of web document for the user's menu and the execution of CGI Program for monitoring and controling the Internet appliance, and satisfying only the indispensable requirements of HTTP which are necessary for the interface with the conventional web browsers. For the evaluation of its feasibility, each module has been implemented on Linux environment, and tested with the MS Explorer 6.0.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집
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• pp.900-904
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• 2009

The measurement of contact wire uplift in electric railway is one of the most test method to accept the maximum permitted speed of new vehicles or pantographs. The contact wire uplift can be measured for shot periods when pantograph is running in monitoring station. This paper describes the development of two different methods for contact uplift measurement using vision-based system and wireless online monitoring system. Our vision-based system employs a high-speed CMOS (Complementary Metal Oxide Semiconductor) camera with gigabit ethernet LAN. The development of a real-time remote monitoring system that acquires data from any kind of sensor to be transmitted by wireless communication from overhead line and structure at 25 kV to a computer in catenary system. The proposed two kind of different measurement systems to evaluation for dynamic uplift of overhead contact wire shows promising on-field applications for high speed train such as Korea Tilting Train (TTX) and Korea Train eXpress (KTX).