• 대한의용생체공학회:의공학회지
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• 제16권4호
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• pp.457-462
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• 1995

본 논문에서는 골절 치료에 사용되고 있는 기존의 금속판과 나사고정 장치를 개선하여, 뼈에 점진적인 생리하중을 가할 수 있도록 고안된 내고정 장치를 살펴보았다. 이 장치는 골절판과 나사를 결합할 때, 그 사이에 생분해성 재질이나 기타 댐핑 특성이 우수한 재질의 와셔를 삽입하는 것을 그 특징으로 한다. 본 논문에서는 주로 이 장치의 충격 흡수 특성을 파악하기 위해, 돼지 대퇴골과 소 경골에대해 충격 망치를 이용하여 얻은 진동 실험 결과를 보여주며, 특히 와셔의 유무에 따른 충격 흡수 특성을 실험적으로 비교하였다.

• 대한기계학회논문집
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• 제13권4호
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• pp.643-652
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• 1989

본 연구에서는 저자들에 의해 개발된 보와 판의 동적 유한 요소법으로 보형상을 지닌 적층 복합재의 형상비(길이/폭)와 적층 형태의 변화에 따른 충격 해석시 어느 이론의 결과가 더욱 적합한지에 대한 타당성 여부를 검토하고자 한다.

• Nuclear Engineering and Technology
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• 제24권2호
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• pp.111-120
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• 1992

본 논문은 안전정지지진에 대한 spacer grid충격하중의 동적특성을 고찰한 것이다. 안전정지지 진 (SSE： Safe Shutodown Earthquake)을 가진력으로 사용하였고 모델로는 가장 긴 15 row의 핵연료집합체 모델을 사용하였다. 외부에서 제공되는 입력데이타의 불확실성을 보상하기 위하여 흔히 사용되는 10%증가된 입력값과, NRC 권고사항인 입력응답스펙트럼의 이동효과의 영향이 평가되었다. 평가대상으로는 spacer grid의 충격력이 사용되었다. 해석결과로서 입력응답 스펙트럼의 이동효과의 영향은 거의 무시할 수 있으나 증가된 입력값의 영향은 spacer grid의 충격력에 큰 영향을 줌을 알 수 있었다. 따라서 원자로노심의 동적응답을 위해서는 입력응답 스펙트럼을 이동시키면서 해석할 필요가 없음을 확인하였다.

• 수산해양기술연구
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• 제20권2호
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• pp.96-104
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• 1984

1. slam충격수 N(T)는 전부수선에서 거리가 증가할수록 감소하며, N(T)=1인 위치가 제한점으로 되며, 제한점이 되는 위치이후에서는 충격의 영향을 고려치 않아도 무방할 것으로 고려된다. 2. 충격력을 고려한 수직제한깊이는 계획흘수의 1/10로 잡았고, 충격응력에 대해서는 고려된 단면위치에서 압력작용속도의 상이로 인하여, 각각의 단면위치에서 전부선저의 몰입높이에 따라 각각 추정되어야한다. 3. 주어진 단면에 대한 충격력은 압력을 수직한계 높이까지 girth를 따라 계산함으로써 결정할 수 있다. 4. 최대충격력은 전부의 선저판의 형상에 따라 그 작용위치가 달라질 수도 있다. 5. 최대충격력의 약 50% 정도의 힘이 전부선저판의 충격에 소비됨으로, 이는 전부선저판의 적정치수 결정에 도움이 될 것으로 기대된다.

• 대한조선학회논문집
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• 제56권4호
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• pp.308-315
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• 2019

In this study, numerical simulations of slamming impact pressure acting on the flat plate and wedge type models using the cartesian-grid system and Modified Marker-Density Method (MMD method) were performed and the results were examined. The flat plate and wedge type models were selected as target objects, the turbulence characteristics were considered by applying the Sub-Grid Scale (SGS) turbulence model. Through this study, how the pressure acting on the target objects according to the incident angle influences the slamming impact pressure was examined and the results were compared with the flow characteristics of other experimental results. Also, the degree of slamming impact pressure is evaluated with respect to the cartesian-grid system and MMD method, which is easy to use and has a high degree of calculation for free surface.

• 대한안전경영과학회지
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• 제10권2호
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• pp.85-94
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• 2008

The object of this study is to investigate the penetration characteristics according to the change of stacking sequences and curvature radius in the composite laminated shell. They are staked to [02/902]S and [0/902/0]s, their interlaminar number are two and four. We are manufactured to composite laminated shells with various curvature radius. Curvature radius of composite shell is 100, 150, 200mm and ${\infty}$(it's meaning flat-plate). In general, kinetic energy after impact-kinetic energy before impact increased linearly in all specimens. Absorbed energy increased linearly as the curvature increased, and absorbed energy of [02/902]S specimen, which is small interlaminar number, was higher than [0/902/0]s specimen.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 춘계학술대회 논문집
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• pp.524-525
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• 2009

Heavy-weight impact noise(HN) is the most irritating noise in Korean apartment houses. It has been proclaimed standard floor system of 210mm thick slab with isolation material in the wall type structure. But this regulation is applied only new construction field and is not considered remodeling field. In general, the LN can be reduced by using isolation material but HN is known as relating with stiffness, strength & boundary condition of slab. Therefore it is difficulty in improving the HN on remodeling field. In this study, We conducted the reinforcement of concrete slab using C.F.S.(carbon fiber sheet), steel plate and steel beam after on-dol with isolation material on the remodeling field. As the test results, It appeared using C.F.S was no improved but using steel plate & steel beam were a little improved on HN.

• 대한기계학회논문집A
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• 제27권10호
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• pp.1738-1747
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• 2003

Smoothed Particle Hydrodynamics (SPH), a pure Lagrangian numerical method, is applied to analysis of penetration phenomenon of bumper plate which is installed outside of spacecraft hull to protect the spacecraft against hypervelocity meteorite impact. Effects of SPH parameters, such as artificial viscosities, smoothing lengths, numbers of particles and time increments, are analysed by comparing the SPH simulation results with experimental ones with regard to subsequent formation of debris cloud. An optimum range of parameter values is determined by error analysis and various SPH numerical results are compared with experiments.

• 한국소음진동공학회논문집
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• 제19권4호
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• pp.370-377
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• 2009

A simple preliminary analysis is often useful to check a validity of design alternatives before the detailed analysis phase in the viewpoint of efficiency. This paper describes a preliminary analysis procedure for the selection among basket design candidates for the spent fuel shipping cask of Korean standard nuclear power plant. As the cask should maintain the structural integrity in hypothetical accident condition, the case of 9 m drop is significantly considered as the worst scenario among the accident conditions in structural design viewpoint in this paper. As basket design options, totally four different types are considered and analyzed in the point of structural integrity at drop impact and weldability for fabrication. As a result, an insertion round plate type with densely spaced supports turns out to be the best in both of the viewpoints, though the weld plate type shows a bit more design margin.

• Nuclear Engineering and Technology
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• 제45권4호
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• pp.553-564
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• 2013

This study evaluates the local damage of a turbine in an auxiliary building of a nuclear power plant due to an external impact by using the LS-DYNA finite element program. The wall of the auxiliary building is SC structure and the material of the SC wall plate is high manganese steel, which has superior ductility and energy absorbance compared to the ordinary steel used for other SC wall plates. The effects of the material of the wall, collision speed, and angle on the magnitude of the local damage were evaluated by local collision analysis. The analysis revealed that the SC wall made of manganese steel had significantly less damage than the SC wall made of ordinary steel. In conclusion, an SC wall made of manganese steel can have higher effective resistance than an SC wall made of ordinary steel against the local collision of an airplane engine or against a turbine impact.