• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집A
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• pp.109-114
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• 2000

A research fur development of composite body panel is in progress for lightening tare. In this study, experiments on estimation of mechanical properties of LPMC (Low pressure molding compound) including fatigue and impact characteristics were carried out. The experiments show that LPMC satisfied basic requirements of car body panel. The fatigue life of LPMC was predicted and the material degradation due to fatigue and impact were fined out.

• International Journal of Aerospace System Engineering
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• 제3권1호
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• pp.21-24
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• 2016

In this study, a optimal design on the hood automotive using eco-friendly natural fiber composites is performed. The hood of an automobile is determined by dividing the Inner panel shape through optimization phase to outer panel and inner panel. It was performed to optimize the size of the thickness of the inner panel and the outer panel by applying a flax/epoxy composite materials. The optimized shape was evaluated for weight-lightening, stability and the pedestrian collision safety. Through the resin flow analysis are confirmed to molding possibility judgment of product.

• 한국생산제조학회지
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• 제21권5호
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• pp.830-835
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• 2012

A research for application of LDSMC(Low Density Sheet Molding Compound) composite is in progress for lightening the weight. This paper has performed fatigue test and simulation of external panel for Korean commercial vehicle. Before the fatigue test, static test was carried out. From the test, the structural safety was investigated using Goodman diagram. After the static test performance, the fatigue test was conducted at a range of load frequency 5Hz, a stress ratio(R) of 0.05 and an endurance limit of $10^6$ to obtain the S-N curve. The S-N curve is applied to the fatigue analysis of the external panel assembly. The result of FEM analysis was in accord with the experimental result within 83% confidence. It showed that the process to set up the safety range of allowable error is required in process of the design and simulation verification.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집A
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• pp.219-224
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• 2000

A research for development of composite body panel is in progress for lightening tare. Low specific weight LPMC (Low pressure molding compound) has advantages such as lightweight and resistance to dent and corrosion. In this study, tensile, bending and impact tests for the LPMC and SPRC35 (High tension steel plate) were carried out and compared. Although mechanical properties of SPRC35 are better than the LPMC, the LPMC satisfies basic requirements for car body panel. The high temperature exposed LPMC were degraded due to fiber-matrix debonding and deterioration of resin.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 추계 학술논문 발표대회
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• pp.141-142
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• 2015

This literature study is focused on the improvement of lightweight concrete in perspective of foaming agent. Lightweight concrete is the cured concrete as putting required amount of foaming agent to slurry which is a mixture of a certain amount of cement, sand, and water. It has lower density than general concrete, because foaming agent disintegrates numerous bubbles evenly and independently. Thus, it is capable of lightening the weight and great for sound absorption and insulation, In foreign countries, studies for structural lightweight concrete mainly of tunnel grouting and weight lightening of heavy structures are going along actively. Domestically, exterior panel and ALC blocks are alternatively used for flooring. Therefore, this research consider improvement of lightweight concrete in perspective of foaming agent with foundation study.

• 한국자동차공학회논문집
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• 제14권2호
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• pp.57-66
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• 2006

AA5182-polypropylene sandwich sheet was manufactured, and the mechanical properties evaluation was executed in order to identify $L{\ddot{u}}ders$ band that causes fabrication process problem and especially surface roughness. To identify formability, deformation behavior, plastic strain ratio (R-value) and pole figure were measured, and texture analysis was performed. In the case of sandwich sheet, the unstable deformation behavior has decreased. As well, for sandwich sheet, A1 skin could manage the most of load, and the elongation has improved about 45% more than that of A1 skin. The plastic strain ratio of A1 skin and sandwich panel, which indicates serration behavior, was obtained from instantaneous plastic strain ratio evaluation. Also, the planar anisotropy of sandwich sheet has decreased more than that of A1 skin. According to these results, the sandwich sheet produced lightening effect and could control unstable deformation characteristic, that is, surface roughness caused by $L{\ddot{u}}ders$ band. Furthermore, it was proved that the texture control of the rolling attachment of A1 skin is necessary to improve the formability of the sandwich panel.

• 한국방재학회 논문집
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• 제3권2호
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• pp.99-110
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• 2003

본 연구에서는 트랜치 굴착시 토석붕괴 방지시설에 대한 시공상의 안전성과 시공성 그리고 작업성에 주안점을 두어 재료의 경량화 및 구조체의 표준화를 시도하였다. 즉, 위험도 사전평가와 안전관리기법을 검토하고 흙막이 부재의 적용성과 흙막이 구조의 역학적 안정성을 검토하였으며, 이들 결과로부터 흙막이 구조체의 역학적 거동매카니즘 규명과 규격의 표준화를 위하여 경량흙막이 구조체의 구조안전성과 구조해석을 실시하였으며, 그 결과를 요약하면 다음과 같다. 1) 흙막이 구조의 역학적 타당성과 토질역학적 조건을 고려한 신소재 활용성을 확보하기 위하여 흙막이 부재의 역학적 성능과 부재에 작용하는 토압정수를 제시하였으며, 흙막이 구조체의 해석이론과 방법을 제시하였다. 2) 강화합성수지(FRP)를 사용한 경량판넬 부재의 지질구조가 경질점성토인 조건을 대상으로 구조해석 결과, 지하수위 조건에 따라서 판넬의 역학적(휨모멘트, 전단력, 축응력) 특성이 변화하고 있었으며, 역학적 해석결과가 허용응력 범위에 있음을 알 수 있어 이는 경량판넬이 트랜치 굴착시에 흙막이 구조로서 유용성을 알 수 있었다.

• Design & Manufacturing
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• 제11권1호
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• pp.1-6
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• 2017

In these days, due to generalization of using smart mobile phone and wearable device such as smart watch, demand of Cover-glass and touch screen panel for protecting display increases. With increasing the demand of Cover-glass, slimming technique is promising for weight lightening, zero bezel. Cover-glass produced by this technique is required to decreasing thickness with increase strength. In the Cover-glass manufacturing process, mechanical processing and chemical processing has improve in the strength. Generally, Diamond electrodeposition wheel is used in mechanical process. Reinforced glass with the characteristics of the brittle and high hardness was manufactured by using a diamond electrodeposition wheel. At this time, Because of surface of the tool present non-uniform distribution of diamond particle, it has generate Loading of wheel and it has been decrease life of grinding tool, efficiency of grinding, quality and shape accuracy of workpiece. Thus Research is needed to controling particle distribution of diamond electrodeposition wheel uniformly. And it is necessary to study micro hole machining such as proximity senser hole, speaker hole positioned Cover-glass. Reinforced glass with the characteristics of the brittle and high hardness is difficult to machining. Processing of reinforced glass have generated wear of tool, micro cracks. Also, it is decreasing shape accuracy. In this paper, We conducted a study on how to control particle distribution uniformly about the diamond tool manufactured using elecetodeposition processing. It analyzed the factors that affect the arrangement of the particles in the electrodeposition process by design of experiment. And There is produced the grinding tool, which derives an optimum deposition conditions, for processing Cover-glass edge and the machinability was evaluated.

• 한국의학물리학회지:의학물리
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• 제15권1호
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• pp.30-38
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• 2004

목적: 방사선 치료 시 환자의 움직임을 최대한 고정시켜 줄 수 있으며 환자 자세에 대한 Setup 오차를 감소시키고 환자 전신에 산재한 병소를 위치화하고 좌표화할 수 있는 전신 정위 고정장치 제작과 제작한 고정장치에 대한 고정효과 및 재현성을 나타내는 환자 자세의 Setup 오차를 평가하였다. 대상 및 방법: 자체 제작한 고정장치는 크게 기본판(base plate)과 고정틀(Immobilizer), Vacuum cushion, 벨트로 이루어진다. 기본판은 50${\times}$130${\times}$1 ㎤ 베크라이트로 고정틀은 견고한 아세탈 재질을 사용하여 제작하였다. 초기의 Lax frame의 경우, side panel에 부착되어 있는 좌표계(coordinates)를 기본판 바닥에 radiopaque catheter wire를 사용하여 N 타입으로 새겨서 넣어 위치측정이 가능한 좌표계로 적용할 수 있도록 하였다. 제작된 고정장치에 대한 성능실험으로 방사선 투과율 측정 실험과 가상표적을 부착한 지원 환자를 대상으로 표적에 대한 위치측정실험이 수행되었다. 그리고 CCTV 카메라와 Digital Video Recorder (DVR)를 이용하여 획득된 환자 영상을 Matlab 프로그램으로 환자 자세에 대한 Setup 오차를 분석하였다. 결과: 전신 정위 고정장치는 CT 촬영과 방사선치료 시 사용 가능성에 중점을 두고 제작되었다. 이 고정장치의 구조는 갠트리의 회전각의 변화에 따라 충돌하지 않게 제작되었고 측면으로 경사지게 입사되는 빔의 투과율을 최대화할 수 있게 제작되었다. 고정틀의 고정효과를 높여주는 고정벨트는 입사된 빔의 방향에 방해되지 않게 제작되었다. 고정장치에 대한 방사선 투과율은 10과 21 MV의 에너지에서 95, 95%로 측정되었고 지원 환자에 부착한 가상 표적의 위치는 CT 촬영으로 파악할 수 있었다. Matlab 프로그램으로 분석한 setup 오차는 흉부의 측면과 중심부위에서 3.69$\pm$1.60, 2.14$\pm$0.78 mm이고 복부의 측면과 중심부위에서 7.11$\pm$2.10, 6.54$\pm$2.22 mm이며 여자 환자 경우, 가슴 측면의 Setup 오차는 6.33$\pm$1.55 mm으로 측정되었다. 결론: 전신 정위 고정장치의 제작과 실험을 통해 extra-cranial 암에 대한 방사선수술에서 매우 실용적이고 유용하게 사용될 것으로 사료되며 표적 위치 결정과 환자 고정 도구로서 사용될 것이다. 더 많은 환자 치료자세의 Setup 오차 측정이 수행되면 정확한 환자의 Setup 오차의 결과를 향상시킬 수 있을 것으로 기대된다.