• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.05a
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• pp.53-56
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• 2006

This paper describes performance design of a solid rocket motor on which thrust cut-off system is installed, and evaluates performance of a rocket motor according to a size of TCO ports. TCO system installed on motors was made to carry out firing tests, and the trend of thrust due to various sizes of TCO port was analyzed to find the existence of the port size for maximum reversal thrust. Conservation equations were used to design performance of motors and to analyze test results. This technique for performance design will be usefully applied to the design of similar TCO systems.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.5
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• pp.101-106
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• 2006

This paper describes performance design of a solid rocket motor on which thrust cut-off system is installed, and evaluates performance of a rocket motor according to a size of TCO ports. TCO system installed on motors was made to carry out firing tests, and the trend of thrust due to various sizes of TCO port was analyzed to find the existence of the port size for maximum reversal thrust. Conservation equations were used to design performance of motors and to analyze test results. This technique for performance design will be usefully applied to the design of similar TCO systems.

• Journal of the Korean Society of Propulsion Engineers
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• v.9 no.4
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• pp.89-95
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• 2005

Thrust cut off(TCO) system is installed at the port of a rocket motor case forward dome. The snap ring and the closure are escaped sequentially by pulling out a wedge under internal pressure. The hydraulic structural tests of TCO and numerical simulations were performed, and both results were compared to understand the deformation behavior of TCO. By increasing splines symmetrically, the sealing capacity of TCO can be improved significantly. The escape pressure of TCO increases according to the increase of friction coefficient and there is a critical friction coefficient beyond which the snap ring can not be nearly escaped even after forced escape of wedge. Under low friction coefficient the snap ring is contracted to radial direction and easily escaped. But, under high friction coefficient, the snap ring can not be escaped from the port even after severe plastic deformation.

• Proceedings of the Korean Information Science Society Conference
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• 2004.10a
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• pp.643-645
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• 2004

네트워크가 복잡해지면서 다양한 형태의 위험에 노출된다. 일반적인 보안 솔루션으로 사용하는 방화벽(Firewall)이나 침입탐지시스템(IDS)은 허가받지 않은 외부의 접속이나 알려진 공격만을 차단하는 단순하고 수동적인 시스템이다. 이에 반해 허니팟은 웹서버와 같은 실제 Front-End 시스템과 유사하거나, 밀접한 관련을 갖고 직접적으로 반응하므로 신뢰성 높은 실시간 정보를 얻을 수 있어서 관리자가 다양한 위협에 능동적이고 효과적으로 대응할 수 있다. 실제로 웜이나 DRDoS(Distributed Reflection DoS)등 수분만에 네트워크를 점유하는 자동화 공격과 함께 시스템 구성 취약점을 파고들거나 계정 획득을 통한 DB서버 등의 Back-End 시스템에 대한 수동 공격이 혼재한다. 따라서 시스템 전반적인 관리의 중요성이 강조되고 있다. 본 논문에서는 그간의 실험결과를 바탕으로 가상 머신으로 허니팟을 구성하고 특성별로 포트를 분리하여 관리하는 허니넷을 제안하고자 한다 이를 통해 1) 유연한 보안 시스템 구성이 가능하고 2) 관리 효율이 높아지며 3) 하드웨어 도입 비용 절감을 통해 시스템의 TCO(Totai Cost of Ownership)를 감소시키는 효과를 기대할 수 있다.