• Journal of the korean Society of Automotive Engineers
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• v.16 no.2
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• pp.1-11
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• 1994

여기서는 자동차를 중심으로한 동 부문에 새롭게 닥쳐오고 있는 그린 충격파, 즉, 몬트리올 의정서와 기후변화협약에 대해 알아보고 이에 대한 대응방안을 살펴 보고자 한다. 1. 자동차 관련 환경문제. 2. 몬트리올 의정서 : 지구 오존층파괴 규제. 3. 기후변화협약 : 지구온난화현상 규제. 4. 수송부문의 에너지절약대책.

• Journal of the Microelectronics and Packaging Society
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• v.14 no.1
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• pp.39-47
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• 2007

It is investigated how KOH and Rthylenediamine(EDA) treatment conditions on Polyimide film surface affect the interfacial fracture energy between electroless plated Ni and Polyimide film by $180^{\circ}$ peel test. Estimated values of interfacial fracture energy were 24.5 g/mm and 33.3 g/mm for the KOH treatment times under 1 and 5 minutes, respectively, while, those were 31.6 g/mm and 22.3 g/mm for EDA treatment times under 1 and 5 minutes, respectively. Interfacial bonding between electroless plated Ni and Polyimide seems to be dominated by chemical bonding effect rather than mechanical interlocking effect. It is found that chemical treatment produces carboxyl and mine functional groups which are closely related the interfacial bonding mechanism. Finally, it is speculated that interfacial fracture energy seems to be controlled by O=C-O bonding near cohesive failure region.

• Composites Research
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• v.12 no.1
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• pp.68-75
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• 1999

This study has observed that the dynamic behavior of Metal Matrix Composites (MMCs) in low velocity impact varies with impact velocity. MMCs with 15 fiber volume percent were fabricated by using the squeeze casting method. The AC8A was used as the matrix, and the alumina and the carbon were used as reinforcements. The tensile and vibration tests conducted yielded the yielded the tensile stress and elastic modulus of MMCs The low pass filter and instrumented impact test machine was adopted to study dynamic behaviors of MMCs corresponding to impact velocity. Stable impact signals were obtained by using the low pass filter. Impact corresponding to impact velocity. Stable impact signals were obtained by using the low pass filter. Impact energy of unreinforced alloy and MM s increased as the impact velocity increased. The increase of crack propagation energy was especially prominent, but the dynamic toughness of each material did not change much. To show the relation between crack initiation energy and dynamic fracture toughness, a simple model was proposed by using the strain energy and stress distribution at notch. The model revealed that crack initiation energy is proportional to the square of dynamic fracture toughness and inversely proportional to elastic modulus.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.3
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• pp.314-318
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• 2006

This study is to analyze the intensity of welding part by simulating the dynamic procedure during the fracture of plates with spot welding. The upper and tower plates attached with spot welding can be seen to fall apart at the elapsed time of 0.64 ms after the upper plate is stretched from the lower plate. The maximum von Mises stress is shown at the welding part in the mid of upper and lower plates. The internal energy decreases largely and the kinetic energy increases suddenly near the elapsed time of 0.64 ms when welding part breaks down. The sliding energy decreases with step-by-step style as the time elapses. The value of this energy becomes 0 at the elapsed time of 0.2 ms and on the contrary, two plates stick each other as this value becomes a minus after this time.

• Explosives and Blasting
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• v.37 no.3
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• pp.25-33
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• 2019

Controlling the blast-induced damage zone(BDZ) in mining excavation is a significant issue for the safety of employees and the maintenance of facilities. Numerous studies have been conducted to accurately predict the BDZ in underground mining. This study employed the dynamic fracture process analysis (DFPA) to estimate the BDZ from a single hole blasting. The estimated BDZ were compared with the results obtained by Swedish empirical equation. The DFPA was also used to investigate the control mechanism of BDZ and fracture plane formation around perimeter holes for underground mining blasting.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2002.05a
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• pp.155-160
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• 2002

최근 들어서 오존층을 파괴하는 것으로 알려진 CFC와 같은 냉매를 사용하지 않고 허니컴식 제습rotor와 rotor식 현열교환기로 구성된 '흡착식제습냉난방시스템'이 개발되어 실용화 단계에 있다. 제습제를 이용한 냉방시스템은 에너지측면에서 효율적이고, 비용 면에서 경제적이며, 환경친화적이다.(중략)

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1999.05a
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• pp.55-61
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• 1999

최근 국내외적으로 지구온난화, 산성비, 오존층파괴 등의 환경문제가 심각하게 대두되기 시작하면서 화석연료 사용에 대한 규제가 점차적으로 강화되고 있다. 이와같은 상황에서 기존의 미분탄 화력발전시스템에 비해서 NOx, SOx, $CO_2$, 분진 등의 대기오염물질을 현저히 줄일 수 있으며 발전효율도 높아서 석탄 사용에 따른 지구의 환경오염 저감과 에너지의 효율적인 이용 측면에서 석탄가스화 복합발전 시스템은 청정석탄 이용기술로 크게 관심을 모으고 있어서 국내외적으로 관련연구가 활발히 진행중이다.(중략)

• Magazine of the Korea Concrete Institute
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• v.6 no.1
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• pp.131-141
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• 1994

This experimental study was performed to lnvestigate the effects of the lergths dnd volume contents of glued hooked steel fiber for the fracture toughness and strength of c oncretc. The notched steel fiber reinforced concrete beams with different flber length(30, 60mm) and fiber volume content(O.0, 0.5, 1.0, 1.5, 2.0%) were tested under 3-point benclmg, md 1 he flexural strengths, fracture energy and CMOD were obtained from the experimental data. The fracture energy v~ds used as d means to evaluate the fracture toughness ot concrete. The results showed that the frdcture toughness and 5trength of conuett. were generally increased ds the content of steel fiber was inc~edsed, arid the length of steel ilber had a great efiect on the flexural strength but little on the compressive itrength and fractule toughness. And also, considering the distributions of steel fiber, workablity and the maxinium size of coarse dqgregates, the optimum content of steel fiber seemed to be about 1.0 '0, and when lts length uias longer the results were somewhat tavorable.

• Electric Engineers Magazine
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• v.208 no.12
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• pp.24-31
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• 1999

인류의 생존을 지켜주는 것은 공기와 물이라 할 수 있다. 이처럼 소중한 공기와 물이 인간의 욕구충족을 위해 인간에 의해 파괴당하고 있다는 사실은 엄연한 현실이며 알면서도 인간 서로가 파괴해가고 있다. 아직도 우리는 지구 이외에 전체의 어느 한곳에도 우리가 이주해 할 수 있는 장소를 발견하지 못하고 있으며 달이나 화성, 목성 등 어느 위성에도 인간이 살 수 있는 징후를 찾지 못하고 있다.

• Proceedings of the KWS Conference
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• 1991.11a
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• pp.105-107
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• 1991