• 한국산업융합학회 논문집
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• 제27권2_2호
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• pp.357-361
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• 2024

Halloysite nanotube (HNT) has a nanotube structure with the chemical formula of Al₂Si₂O₅(OH)₄·nH₂O and is a natural sediment of aluminosilicate. HNT has been used as additive to improve the mechanical properties of epoxy composites with exchange of amine group as a terminal functional group using huge amount of organic solvents. In order to save time and simplify complicated procedures, a dry coating machine was designed and used for amine group exchange in previous research. For better applications, it was conducted with different parameters and with scale up settings. Best condition was found to reduce usage of solvent, time and man power.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2410-2414
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• 2008

Human heart valves diseased by congenital heart defects, rheumatic fever, bacterial infection, cancer may cause stenosis or insufficiency in the valves. Treatment may be with medication but often involves valve repair or replacement (insertion of an artificial heart valve). Bileaflet mechanical heart valves (BMHVs) are widely implanted to replace the diseased heart valves, but still suffer from complications such as hemolysis, platelet activation, tissue overgrowth and device failure. These complications are closely related to both flow characteristics through the valves and leaflet dynamics. In this study, the physiological flow interacting with the moving leaflets in a bileaflet mechanical heart valve (BMHV) is simulated with a strongly coupled implicit fluid-structure interaction (FSI) method which is newly organized based on the Arbitrary-Lagrangian-Eulerian (ALE) approach and the dynamic mesh method (remeshing) in FLUENT. The simulated results are in good agreement with previous experimental studies. This study shows the applicability of the present FSI model to the complicated physics interacting between fluid flow and moving boundary.

• 해양환경안전학회지
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• 제26권6호
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• pp.689-697
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• 2020

위험유해물질(HNS, Hazardous and Noxious Substances)은 해상운송 과정에서 다양한 사고에 노출되어 있어 많은 양이 바다에 유출될 우려가 있다. HNS 유출에 따른 해양환경의 손상은 유류 유출에 의한 손상보다도 훨씬 큰 것으로 알려져 있다. 특히 해저로 침강하여 침적되는 HNS는 해저생태계에 돌이키기 어려운 피해를 주게 되므로, 반드시 회수되어야 한다. 해저로부터 HNS를 회수하기 위해서는 해저침적 HNS에 대한 정확한 탐지, 안정화 처리 및 회수를 위한 절차와 장비가 필요하다. 그 중에서도 기계적 회수장치를 개발하기 위해서는 성능지표를 이용하여 성능요건을 선정하고, 이를 토대로 기계적 회수장치에 대한 개념설계가 이루어져야 한다. 따라서 본 연구에서는 해저침적 HNS의 회수 절차에서 요구되는 기계적 회수장치에 대한 개념설계안을 제시하였다. 개념설계안으로 해저침적 HNS를 회수하기 위한 기본 시나리오를 제시하고, 자체적 밀폐 성능을 가지는 흡인 기초를 활용하는 방안을 채택하였다. 기계적 회수장치는 흡인 기초, 오염 방지, 펌프 시스템, 제어 시스템, 모니터링 장비, 위치정보 장비, 이송 장비, 탱크로 구성된다. 이러한 개념설계안은 기계적 회수장치의 부품 및 형상을 결정하는 기본설계에 반영되어 활용될 것으로 기대된다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2005년도 창립60주년 기념 추계 학술대회
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• pp.16.2-16.2
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• 2005

• 대한기계학회:학술대회논문집
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• 대한기계학회 2005년도 창립60주년 기념 추계 학술대회
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• pp.4.2-4.2
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• 2005

• International Journal of Safety
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• 제7권2호
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• pp.27-30
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• 2008

In the 21st century, safety issues in the strained silicon industry, such as dislocation injection, should be carefully considered. This is because a microelectronic device usually contains sharp features (e.g., edges and corners) that may intensify stresses, inject dislocations into silicon, and ultimately cause the failure of the device. In this paper, critical residual stresses in various strained structures are calculated. It is confirmed that this model correctly predicts trends and the order of magnitude of critical residual stresses.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.643-645
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• 2008

To obtain weight reduction and high performance, level set based topology optimization in magnetic fields is promising for the design of magnetic devices where the precise boundary shape and topological chanages are required. Level set function is introduced to represent ferromagnetic material boundaries and material properties of the magnetic reluctivity are determined. The optimization problem is formulated for maximizing the actuating force in a prescribed direction under limited usage of ferromagnetic material.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집A
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• pp.819-824
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• 2001

Most of rail fastening system used in the interior have depended on the foreign technologies. In this study, new rail fastening device is developed to estabilish the domestic technology. Especially, Pandrol and Vossloh rail fastening devices are analyzed to utilize the weak and strong points. New rail fastening device is designed to combine advantages of two other foreign devices.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.910-913
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• 2002

We have achieved an improved stability of an analog electro-optic effect in FLC/polymer composite films. The optimization of device depends on both the composition of the FLC/polymer mixture and the energy of UV irradiation. This device exhibits continuous gray scales and the mechanical stability against external forces.

• Journal of Chest Surgery
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• 제26권11호
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• pp.890-893
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• 1993

The first successful percutaneous transcatheter occlusion technique for patent ductus arteriosus achived by Rashkind in 1977.Transcatheter occlusion with the Rashikind double umbrella device is now widely accepted as treatment for patent ductus arterisus. The reported complications include embolization of the device, psudocoarctation left pulmonary artery stenosis, residual shunts, and mechanical hemolysis. We report two cases of severe hemolysis after occlusion of PDA with Rashkind occluder.