• 한국안전학회지
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• 제30권3호
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• pp.7-12
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• 2015

CFRP composites are used as primary structural members in various industrial fields because their specific strength and specific stiffness are excellent in comparison to conventional metals. Their usage is expanding to high added-value industrial fields because they are more than 50% lighter than metals, and have excellent heat resistance and wear resistance. However, when CFRP composites suffer impact damage, destruction of fiber and interface delamination occur. This causes an unexpected deterioration of strength, and for this reason it is very difficult to ensure the reliability of the excellent mechanical properties. Therefore, for the destruction mechanism in bending with impact damage, this study investigated the reinforcement data regarding various external loads by identifying the consequential strength deterioration. Specimens were damaged by impact with a steel ball propelled by air pressure. Decrease in bending strength caused by the tension and compression of the impact side, and depending on the lamination direction of fiber and interface inside the specimen. From the bending test it was found that the bending strength reduced when the impact energy increased. Especially in the case of compression on the impact side, as tensile stress occurred at the damage starting point, causing rapid failure and a substantially reduced failure strength.

• 한국융합학회논문지
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• 제11권4호
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• pp.173-177
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• 2020

본 연구에서는 현재 전복 사고가 자주 발생하는 Model A와 Model B의 중형 세단 차량들의 사이드 도어들을 구조 해석으로 서로 비교한다. 구조해석 결과, 두 모델 모두 전복 사고나 충격 시 하중이 작용되는 부분에서 최대 변형이 일어났고 2개의 모델 중 Model A가 Model B와 비교하면 충격력을 더 견딜 수 있다. 또한 도어의 모서리 부분에서 최대 응력이 일어났고 Model B가 Model A보다 2.5 배 더 응력이 커진다. 충돌 사고가 일어날 시, 2개의 모델 중 그 최대 응력이 작은 Model A가 Model B와 비교하면 더 큰 충격력을 견딜 수 있다. Model B가 Model A보다 더 큰 변형량을 갖는 것으로 보아 측면 충돌 사고에서는 Model A보다 위험할 것으로 사료된다. 차종별 차량 옆문의 충돌해석을 적용함으로서 본 논문에서의 연구 결과는 미적인 설계를 적용할 수 있는 융합 연구자료로서 유리하다고 여겨진다.

• 자동차안전학회지
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• 제10권3호
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• pp.7-12
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• 2018

The Korean New Car Assessment Program (KNCAP) is a program to evaluate the safety of automobiles. In the safety assessment method, there are frontal collision, partial frontal collision, side collision, pillar collision, and left stability in the collision safety category. Among them, Korean in-depth analysis data shows that there are a lot of side collision accidents and it is necessary to protect them. This study will analyze the side collision accident that occurred in actual traffic accident based on Korea In-Depth Accident Study (KIDAS) and investigate the effect of center airbag on passenger in under side collision. In addition, with simulated side collision scenarios in the various side impact directions, it was investigated how the center airbag affects the driver and passenger in terms of kinematic and injury levels.

• 대한기계학회논문집A
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• 제36권10호
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• pp.1155-1162
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• 2012

알루미늄 크래쉬 박스는 저속충돌조건에서 프론트 사이드 멤버를 변형을 방지하기 위한 부품이다. 본 연구에서는 저속충돌조건에서 비드형상이 알루미늄 크래쉬 박스의 충돌성능에 미치는 영향을 분석하였다. Edge concave, surface convex 와 surface concave 타입의 비드형상들에 대한 충돌해석 및 실험을 수행하여 비드가 없는 normal 타입의 알루미늄 크래쉬 박스의 충돌성능과 비교분석하였다. 충돌성능은 저속충돌조건에서 크래쉬 박스의 초기 최대하중 및 충돌에너지 흡수능으로 평가하였다. 이를 검증하기 위해 알루미늄 크래쉬 박스와 결합된 프론트 사이드 멤버에 대해 저속충돌실험 수행하고, 이를 분석하였다. Surface concave 타입의 비드가 삽입된 알루미늄 크래쉬 박스 경우, 프론트 사이드 멤버의 변형을 방지할 수 있음을 확인하였다.

• Composites Research
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• 제30권2호
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• pp.158-164
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• 2017

섬유금속적층판은 금속 판재와 섬유 강화 플라스틱을 적층한 하이브리드 소재 중 하나다. 섬유금속적층판은 부품 경량화 측면을 고려했을 시, 뛰어난 충격흡수능력을 가지고 있기 때문에 자동차 및 항공우주 산업에서 적용 및 연구를 진행하고 있는 추세다. 특히, 자동차의 측면 도어 임펙트 빔의 경우, 기존의 금속소재에서 복합재료로 대체하기 위한 연구가 활발히 진행 중이다. 본 연구에서는 자동차의 측면 도어 임펙트 빔을 금속소재와 자기 강화형 폴리프로필렌을 적층한 섬유금속적층판으로 대체하는 것이 목표다. 3가지 종류의 임펙트 빔의 3점 굽힘 시험 수치해석을 통해 단면적 대비 굽힘 저항력의 크기를 비교하였다. 그 후, 제작 실현성을 고려하여 굽힘 저항력이 우수한 이중모자형 임펙트 빔을 순수 DP 980과 섬유금속적층판으로 제작하여 자동차 측면 도어에 설치된 모델을 상정하고 충돌 해석을 수행하였다. 결과적으로 섬유금속적층판을 사용한 임펙트 빔은 기존의 DP 980보다 무게 대비 충격 에너지 흡수 능력이 약 7배 높음을 알 수 있었다.

• International Journal of Automotive Technology
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• 제5권1호
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• pp.23-31
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• 2004

Secondary movements of piston in the bore clearance are closely related to the side impact to the engine block as well as many tribological problems. Some of the major parameters that influence these kinds of movements are piston profile shapes (barrel and flat), piston pin offsets and the magnitudes of bore clearances. In our study, computational investigations are performed about the piston movements in the bore clearance by changing the skirt profiles and piston offsets. In this work, it is found that curved profile and larger offset magnitude to thrust side provide better performance that has low side impact during the engine cycle.

• 자동차안전학회지
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• 제7권1호
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• pp.40-44
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• 2015

In recent years, WorldSID dummy has been continuously developed and investigated to be a better represent biolfidelic ATD as well as a device for replacement of the current existing EuroSID-2. In Korea, the side impact accident is one of the major severe accidents in terms of numbers of accidents and fatality. Since 2003, 50kph 90degree side crash test has been initiated as a safety standard with EuroSID-1 at the first stage and also same time 55kph impact speed test has been conducted as a part of KNCAP program. Currently only EuroSID-2 is accepted as a regulatory tool for vehicle certification and KNCAP. In order to make use of WorldSID of KNCAP in the distant futuer the tests with WorldSID is conducted experimentally.

• 한국정밀공학회지
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• 제21권6호
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• pp.179-187
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• 2004

In this study, for a safety assessment of wheelchair occupant in frontal and side impact of wheelchair loaded vehicle, a sled impact test was perfumed. Each test was carried out total 6 times, by using Hybrid III 50th-percentile male dummy in light weight and electric wheelchair. We estimate MC(Motion Criteria), CIC(Combined Injury Criteria), HIC(Head Injury Criteria), HNIC(Head and Neck Injury Criteria) based on measured data. Through this study, we make an assessment of risk analysis of wheelchair occupant and wheelchair. Through this study, safety standard of wheelchair is to be evaluated.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.7-12
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• 2008

A hot stamping technology of vehicle door impact beam made of thin sheet steel has been developed, with the aim of ensuring occupant safety in a side collision. This technology has been implemented to increase the strength of vehicle body parts and to reduce not only the weight of door impact beam but also the number of work processes. Mechanical tests were performed to obtain material properties of hot-stamped specimen and those were used as input data in stamping and structural simulation for optimal design of door impact beam. Strength of hot-stamped door impact beam increased to the value 102% higher than that of conventional pipe-shaped door impact beam and structural simulation showed that hot-stamped door impact beam achieved 28% weight reduction.

• 한국기계기술학회지
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• 제13권1호
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• pp.49-56
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• 2011

The neck injury occupies the most of injury that happened by the rear impact car accident. This study was analyzed about influence of the neck injury in low speed rear impact and car crash accident investigation. There is no neck injury in low speed side rear impact. On the other hand, there is initial neck injury symptom of 10 % but no long-term neck injury symptom in low speed offset rear impact. It appeared that the possibility of neck injury in low speed rear impact is low. For the more study about the neck injury, it should be evaluate the effects of the car body structure, frame structure and rear crash pattern.