• Proceedings of the KSR Conference
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• 2011.10a
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• pp.1478-1485
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• 2011

Subway stations have a characteristic that the facilities in the ceiling should be checked, replaced or expanded frequently. The frequent opening and closing of ceiling panels result in the damage of panels which makes them easily disengaged. In order to resolve this issue, which is giving difficulty in the maintenance of the stations, this study suggest a sliding ceiling panel structure which can be opened and closed with sliding mechanism, instead of current fixed type ceiling panels. The sliding ceiling panel will prevent the damage of ceiling panels due to frequent disengagement and engagement. It will increase the durability of ceiling panel and extend the cycle of panel replacement. Accordingly, the maintenance cost will be also reduced.

• The Korean Publising Journal, Monthly
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• s.345
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• pp.84-85
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• 2004

• The Korean Publising Journal, Monthly
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• s.347
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• pp.86-87
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• 2004

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.2
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• pp.227-235
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• 2010

This paper introduces the design of a bridge transport system with a telescopic tube for positioning equipment to perform remote handling tasks in a radioactive facility. It consists of an extensible and retractable telescopic tube assembly for z-direction motion, a cabling system for management of power and signal cables, and a trolley system for transverse motion and accommodating servo drives. The working environment for the bridge transport system with the telescopic tube requires strict geometrical constraints, including a short height, short telescopic tube length when retracted, and a long stroke. These constraints were met by solving a nonlinear programming problem involving the optimal dimensions. This paper introduces a cabling system for effective management of cables with changeable lengths to accommodate telescopic motions and a selection guide for servo drives that are sufficient to drive the system.

• Agrochemical news magazine
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• v.21 no.4 s.157
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• pp.18-21
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• 2000

• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.2
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• pp.163-170
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• 2011

Natural stream disasters due to a localized torrential and flash flood has occurring in a small stream especially un-implemented small stream. The survey results during ten years from 2001 to 2010 show that the small stream implementation projects (SSIPs) expenses is increasing with the damages is generally decreasing with variableness in which SSIPs is contributing to disaster prevention in a small stream. This study develop guideline for the selection of SSIPs to support high risk stream at first and save the small streams located on the mountainous area, prevention area and agricultural area which streams have no implementation effects. Developed sub items in guideline are evaluated by stream data collected from 212 small streams where it is proved that sub distance of each item are well arranged by normal distribution. This SSIPs is useful for selecting high risk small stream at first to maximize disaster risk reduction with minimum SSIPs expenses. Also, this SSIPs is used for leading to save small stream on the upstream to minimize flood damages on the down stream with selection a SSIP purchasing agricultural land for preparing flood plane.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2004.03a
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• pp.141-146
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• 2004

본 연구에서는 Canada Southern Alberta Network의 6곳의 GPS(Global Positioning System) 상시관측소 데이터를 바탕으로 관측소와 각 GPS 위성간의 시선방향 습윤지연량을 결정하였다. 고정밀 GPS 데이터를 이용하여 천정방향 습윤지연량을 결정하고 이를 WVR(Water Vapor Radiometer)에서 측정한 천정방향 습윤지연량과 비교하였다. 그 결과 WVR의 천정방향 습윤지연량과 비교할 때 GPS로 관측한 천정방향 습윤지연량은 최대 1.39cm, 최소 0.99cm의 RMS 오차를 보였다. 또한 GPS로 관측한 시선방향 습윤지연량은 WVR과 비교할 때, PRN 25번 위성의 경우최대 17cm, 최소 0.05cm의 차이가 났다.

• KLA journal
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• v.45 no.5 s.348
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• pp.53-57
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• 2004

이번 도서관문화 5월호에서는 한국도서관협회와 국립중앙도서관이 공동으로 주최하는 도서관 문화학교에 지난 4월 2일(금)과 9일(금)에 걸쳐 ‘책의 기원과 미래’의 주제로 특강을 한 천정환씨를 만나보았다.

• Journal of the Korean earth science society
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• v.21 no.4
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• pp.380-388
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• 2000

The estimation of tropospheric zenith delay over the Seoul-Jecheon area using GPS is presented. Over the past ten years, the world-wide industrial nations have been intensively concerned over increasing GPS surveyings in the various fields of earth science. To preserve precise positioning under various weather conditions, relationships between tropospheric zenith delay and GPS accuracy are analyzed. GPS accuracies are compared with tropospheric zenith delay produced by Bernese 4.0 software. Errors of tropospheric delay are 20cm in mean and reduced up to 5cm when tropospheric correction models are used. Correlation between error of GPS and tropospheric zenith delay plays a positive role to monitor the migration of weather front in the established Korean GPS network.

• 한국지구과학회:학술대회논문집
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• 2006.02a
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• pp.133-133
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• 2006