• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2008.04a
• /
• pp.778-781
• /
• 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.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.22 no.3
• /
• pp.218-221
• /
• 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).

• Proceedings of the KSR Conference
• /
• 2006.11b
• /
• pp.1483-1487
• /
• 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.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2006.06a
• /
• pp.531-532
• /
• 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.

• Proceedings of the KSR Conference
• /
• 2008.11b
• /
• pp.1227-1230
• /
• 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.

• Journal of Internet Computing and Services
• /
• v.4 no.6
• /
• pp.13-24
• /
• 2003

Grid technology requires use of geographically distributed resources from multiple domains. Resource monitoring services or tools consisting sensors or agents will run on many systems to find static resource information (such as architecture vendor, OS name and version, MIPS rate, memory size, CPU capacity, disk size, and NIC information) and dynamic resource information (CPU usage, network usage(bandwidth, latency), memory usage, etc.). Thus monitoring itself may cause system overhead. This paper proposes the optimal monitoring interval to reduce the cost of monitoring services and the dynamic monitoring interval to measure monitoring events accurately. By employing two features, we find out unnecessary system overhead is significantly reduced and accuracy of events is still acquired.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.43 no.3 s.309
• /
• pp.1-9
• /
• 2006

SNMP is a standard protocol for management of networking devices. Nowadays, most computer systems have capability to act as SNMP agents. In this paper, we developed a low overhead version of SNMP library for embedded systems, and implemented a monitoring software based on the library for a large number of target systems. The monitoring system consists of a monitoring server, SNMP agents, and client programs. The monitoring server collects status information from SNMP agents running on the monitoring targets, and sends summary information to client programs. We implemented two versions of clients, Java based standalone program and Web based program.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2006.06a
• /
• pp.543-544
• /
• 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
• /
• v.12 no.4
• /
• pp.123-131
• /
• 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.

• Proceedings of the KSR Conference
• /
• 2009.05a
• /
• pp.900-904
• /
• 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).