• 한국기계가공학회지
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• 제17권6호
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• pp.61-67
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• 2018

The face milling cutter, which is mainly used for the face milling, is used to cut the Carbon steel(SM20C) in the machining center for 5 times and 10 times respectively. This study clarify the dimensional accuracy characteristics according to the number of fine machining varied the condition of cutting depth, table feed speed and spindle speed. Cutting depth is varied 0.05~0.2mm, table feed speed is varied 0.05~0.2mm/min and spindle speed is varied 1500~2500rpm. As a result, the dimensional accuracy was stable 6 times machining with table feed speed 150mm/min and 10 times machining with table speed 100mm/min and cutting depth 0.05mm regardless times of machining.

• 한국해양공학회지
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• 제18권6호
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• pp.16-21
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• 2004

This study presents the wave forces for spar platforms. The advantage of a spar platform is that it is easy to manufacture and has excellent to motion characteristics. It is important to precisely determine the wave force acting on spar platforms for their basic design of them. We measur the wave exciting force for both the classic spar and truss spar models, and accomplish the numerical calculation using diffraction theory. The results show that experimental values have good agreement with theoretical values. However it is difficult to accurately estimate the value considering the heave plate of truss spar due to the viscosity.

• 콘크리트학회지
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• 제2권3호
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• pp.65-72
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• 1990

섬유 콘크리트 내의 단위 면적당 섬유 개수에 대한 이론식이 공시체의 경계조건의 영향을 고려하여 유도되었다. 또한 단위 면적당의 섬유 개수는 각기 다른 섬유형태, 그리고 다른 용적 혼합율(volume fractions)을 갖는 공시체에 대하여 실험적으로도 산정되었으며 이들 실험치들에 근거한 통계적 해석을 통한 공시체 각 단면에 따른 단위 면적당 강섬유 수의 집중 정도의 차이가 평가 되었다. 또한 vibration에 의한 강섬유의 재향성(reorientation)의 정도는 이론치와 실험치의 차이를 비교함으로서 검토되었다.