• Bulletin of the Korean Chemical Society
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• v.21 no.12
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• pp.1173-1174
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• 2000

• Proceedings of the SOHE Conference
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• 2004.12a
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• pp.94-94
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• 2004

• The Korean Journal of Archival Studies
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• no.38
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• pp.311-316
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• 2013

• Construction Engineering and Management
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• v.20 no.5
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• pp.33-37
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• 2019

• Construction Engineering and Management
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• v.24 no.2
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• pp.30-33
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• 2023

• Nuclear industry
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• v.29 no.7
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• pp.21-24
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• 2009

2009년 경주 윌성 지역에 건설 중이던 중 저준위 방사성폐기물 처분장(이하 방폐장) 건설의 완공이 지하 동굴 굴진 공사중 연약 암반이 발견된 것과 관련하여 애초 계획보다 30개월 지연된다고 지식경제부와 방사성폐기물공단이 발표하였다. 경주 주민들은 이에 대해 방폐장 건설의 안전성에 의혹을 제기하면서 진상조사를 할 것을 요구하였고 지경부는 한국지질학회에 의뢰하여 진상조사단을 구성하여 지연 사유를 조사하도록 하였으며 조사 결과 발표회가 개최되었다. 그러나 이에 만족하지 않고 추가 조사 등을 요구하는 지역 주민들의 요구에 의해 '방폐장 현안사항 해결을 위한 지역 공동협의회'가 구성되었으며 이들이 구성한 '방폐장 안전성 검증조사단'이 방폐장 안전성 확인을 위해 현재 조사 활동을 수행하고 있다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.41-45
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• 1997

To design a control system, it is a elementary point that the stability of the system should be guaranteed. Also, the phase of the system plays an important role for its frequence performance. In this paper, we present two stability criterion of repetitive control system with phase-lead and lag compensator. First, the stability criterion for the servo control system with phase-lead and lag compensator is shown by using small-gain theorem. Second, for the repetitive control system with the compensator, the stability criterion, also, is determined by using small-gain theorem. Two stability criterions show the same results that the stability depends on a coefficient of the phase-lead and lag compensator under some condition in servo control system and repetitive control system.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1601-1602
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• 2015

전력계통에서 진상역률이 될 경우, 경부하시 또는 무부하시 변전소 급전측의 전압보다 말단측의 전압이 높아져 심각할 경우 절연파괴 및 기기에 과전압으로 인한 문제가 발생할 수 있다. 최근 도입된 고속철도 구간에서 무부하시 또는 경부하시 전압이 상승되는 현상이 발생하여 실측 및 시뮬레이션을 통하여 전위 상승에 대한 원인을 검토하고자 한다.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.1590-1595
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• 2003

Direct drive servovalve(DDV) is a kind of one-stage valve since the rotary motion of DC motor is directly transferred to the linear motion of valve spool through the link. Since the structure of DDV is simple, it is less expensive, more reliable and offers reduced internal leakage and reduced sensitivity to fluid contamination. However, the flow force effect on the spool motion is significant such that it induces large steady-state error in a step response. If the proportional control gain is increased to reduce the steady-state error, the system becomes unstable. In order to satisfy the system design requirements, the lead-lag controller is designed using the complex method that is one kind of constrained direct search method.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.11
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• pp.1719-1726
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• 2004

Direct drive servovalve(DDV) is a kind of one-stage valve because the main spool valve is directly driven by the DC motor. Since the structure of DDV is simple, it is less expensive, more reliable and offers reduced internal leakage and reduced sensitivity to fluid contamination. However, the flow force effect on the spool motion is significant such that it induces large steady-state error in a step response. If the proportional control gain is increased to reduce the steady-state error, the system becomes unstable. In order to satisfy the system design requirements, the lead-lag controller is designed using the complex method that is one kind of constrained direct search method.