• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 춘계학술대회 논문집
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• pp.926-931
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• 2002

Although ceramic plates with many micro-hales are used as MCP (Micro-channel plate) for electron amplification, catalytic converters, filters, electrical insulators and thermal conductors in integrated circuits, the drilling of micro-hales in the ceramics is difficult because of their low thermal conductivity, high hardness and brittleness. Therefore, in this work, the machining of ceramic green body fellowed by sintering of green body was employed fur fabricating ceramic plates with many micro-holes. The micro-drilling of alumina green body was performed with diamond abrasive WC drills, and the cutting force w.r.t. drilling times was measured for the determination of toot life. From the investigation of the wear of micro-drill tip w.r.t. drilling times, the wear mechanism of tip during micro-drilling of ceramic green body was suggested.

• 전기학회논문지P
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• 제58권3호
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• pp.351-356
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• 2009

In this study, we analyzed and experimented about electric continuity for human body safety from green cars. And we compared power systems of HEV and examined about human body effect of current and time. We investigated internal and external standards and regulations for human body safety from high voltage electrical equipments. Indirect contact refers to contact between the human body and exposed conductive parts. According to UNECE R100, ISO 23273-3, ISO 6469-3 and Japanese Regulation Attachment 101, electric continuity between any two exposed conductive parts shall not exceed $0.1{\Omega}$. The value of electric continuity was measured below $0.1{\Omega}$ at the actual condition of green car. We expected that the results of these experiments can utilize to data for electrical safety of green car.

• 한국세라믹학회지
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• 제43권12호
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• pp.859-864
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• 2006

For the pressure compaction process of the ceramic powder, the green density is very different with both the ceramic body shape and the processing conditions. The density difference cause non-uniform shrinkages and deformations, and make cracks in the sintered ceramics. In this paper, Material properties of the alumina powder mixed with binder and the friction coefficient between the powder and the tool set were determined through the simple compaction experiments: Also the powder flow characteristics were simulated and the green density was analyzed during the powder compaction process with Finite Element Method (FEM). The results show that the density distributions of the green body were improved at the optimized processing condition and both the possibility of the farming crack generation and rho deformation of the sintered Alumina body were reduced.

• 한국지반신소재학회논문집
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• 제5권3호
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• pp.1-7
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• 2006

1960년대 초 오스트리아에서 개발된 그린월(green wall) 공법은 독립식 콘크리트 보형식의 옹벽으로, 전, 후면 가로보와 세로방향으로 버팀보를 연속적으로 쌓아 올려 내부에 다짐성토를 시행, 구조체가 일체 거동하도록 강성벽체(rigid body)를 형성시키는 옹벽 구조물이다. 국내의 경우, 옹벽 전면 가로보 사이의 공간에 식생이 가능한 친환경적 장점이 있어, 1999년 이후 국내실정을 고려 원지반의 토공량을 최소화할 수 있도록, 쏘일네일 등으로 보강하여 절토 공사현장에 다양하게 적용되고 있는 추세이다. 그러나 그린월 옹벽과 배면에 보강된 쏘일네일이 합벽시공될 경우, 네일에서의 토압분담효과 등에 대한 영향을 고려하지 않고 일반적인 Rankine 토압으로 설계, 시공하여 이중으로 보강공사비용이 투입되고 있는 실정이다. 따라서 본 연구에서는 G$\ddot{a}$ssler(1988)가 제안한 'Two-Body Translation Mechanism(TBTM)'을 이용한 안정해석기법을 수정하여, 네일의 토압 분담효과를 반영할 수 있는 설계기법을 제시하였으며, 본 연구에서 제안한 설계기법을 적용하여 그린월의 보수, 보강공사 비용을 상당부분 감소한 현장설계 사례를 소개하고자 한다. 아울러 본 연구에서 제시한 설계기법을 토대로 계산된 토압을 수치해석 결과와 비교, 검토해 보았다.

• 대한본초학회지
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• 제37권1호
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• pp.11-18
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• 2022

Objectives : Green gram (mung bean) has a cold nature and has been known to detoxify against various side effects that belong to hot in nature. In particular, since it has the effect of detoxifying fever and detoxification to treat swelling, it was also used externally to treat febrile dermatological diseases such as erysipelas and rubella. This study was designed to determine whether green gram exhibits anti-inflammatory effects on contact dermatitis in mice. Methods : We investigated the effects of green gram extract (70% ethanol extract) on skin lesion, skin thickness and weights, melanin and erythema index and spleen body weight ratio in mice with contact dermatitis induced by repeated application of 1-Fluoro-2,4-dinitrobenzene. Results : Topical application of green gram extract ameliorates skin lesions of contact dermatitis such as scale and roughness induces by 1-Fluoro-2,4-dinitrobenzene. green gram extract also suppressed enlargement of skin thicknesses and weights significantly. In addition, green gram extract treatment also lowered erythema index significantly compared to those in the control group. In the histopathological observation, green gram extract prevented epidermal hyperplasia and hyperkeratosis in inflamed tissues. Finally, green gram extract did not affect changes in body weights and the spleen body weight ratio, unlike dexamethasone, which significantly prevented body weight gain and lowered the spleen body weight ratio. Conclusions : These results imply that green gram, which is known to have a detoxifying effect in Korean medicine, can be used in the treatment of contact dermatitis.

• 한국세라믹학회지
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• 제27권1호
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• pp.91-101
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• 1990

The green microstructure and sintering behavior of ZrO2 were analyzed in terms of kinetic stability (measured by the stability ratio ; W) and interfacial characteristics of colloidal suspension. Green density and the most frequent pore radius(MFPR) of green body were directly correlated with the stability ratio. These observations were explained using a concept of the critical stability ratio(Wc) and the potential energy of two interacting particles in colloidal suspension. Analysis of the data also indicates that the potential energy barrier between two interacting colloid particles should be higher than its critical value for a fabrication of ZrO2 green body with dense and uniform microstructure. Besides, we have successfully applied a concept of the donoracceptor interaction to increase the kinetic stability of ZrO2 slip and density of green body.

• 한국세라믹학회지
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• 제31권12호
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• pp.1467-1474
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• 1994

The effects of the dispersion, drying, and binder burning-out on the green-microstructures of gelcasted alumina were studied. The slip consisting of 55 vol% alumina powder and 5 wt% organic materials was well-dispersed by adding 0.28 wt% polyelectrolyte polymer. Green bodies were dried at >85% relative humidity at room temperature. Green-microstructures were observed to be depended on the heating rate during binder burnout. Constant drying rate was not observed in drying process of gelcasted alumina. Sintered body showed its relative density higher than 99% when it was sintered at 1$600^{\circ}C$ for 2 hours.

• Nutrition Research and Practice
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• 제6권2호
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• pp.106-112
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• 2012

This study was conducted to investigate the effects of $Sasa$ $quelpaertensis$ bamboo and green tea on plasma and liver lipids, platelet aggregation, and erythrocyte membrane Na channels in ovariectomized (OVX) rats. Thirty female rats were OVX, and ten female rats were sham-operated at the age of 6 weeks. The rats were divided into four groups at the age of 10 weeks and fed the experiment diets: sham-control, OVX-control, OVX-bamboo leaves (10%), or OVX-green tea leaves (10%) for four weeks. Final body weight increased significantly in the OVX groups compared with that in the sham-control, whereas body weight in the OVX-green tea group decreased significantly compared with that in the OVX-control ($P$ < 0.01). High density lipoprotein (HDL)-cholesterol level decreased in all OVX groups compared with that in the sham-control rats ($P$ < 0.05) but without a difference in plasma total cholesterol. Plasma triglycerides in the OVX-green tea group were significantly lower than those in the sham-control or OVX-control group ($P$ < 0.05). Liver triglycerides increased significantly in the OVX-control compared with those in the sham-control ($P$ < 0.01) but decreased significantly in the OVX-green tea group compared with those in the OVX-control or OVX-bamboo group ($P$ < 0.01). Platelet aggregation in both maximum and initial slope tended to be lower in all OVX rats compared with that in the sham-control rats but was not significantly different. Na-K ATPase tended to increase and Na-K cotransport tended to decrease following ovariectomy. Na-K ATPase decreased significantly in the OVX-green tea group compared with that in the OVX-control group ($P$ < 0.01), and Na-K cotransport increased significantly in the OVX-bamboo and OVX-green tea groups compared with that in the OVX-control ($P$ < 0.05). Femoral bone mineral density tended to be lower in OVX rats than that in the sham-control, whereas the green tea and bamboo leaves groups recovered bone density to some extent. The results show that ovariectomy caused an increase in body weight and liver triglycerides, and that green tea was effective for lowering body weight and triglycerides in OVX rats. Ovariectomy induced an increase in Na efflux via Na-K ATPase and a decrease in Na efflux via Na-K cotransport. Furthermore, consumption of green tea and bamboo leaves affected Na efflux channels, controlling electrolyte and body water balance.

• 반도체디스플레이기술학회지
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• 제19권4호
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• pp.1-5
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• 2020

By adapting black body leadflame and thin film type Green A filter, we successfully demonstrated night vision imaging system (NVIS) Green A compatible LED. Fabricated NVIS compatible LEDs show small form factor compared to that of commercialized NVIS compatible LED. Especially, NVIS radiance and chromaticity of MIL-STD-3009 specification can be satisfied simultaneously and easily by controlling the color temperature of the white LED as well as the concentration of the Green A dye and the thickness of the Green A filter. The optimal dye concentration of the NVIS Green A filter is expected to be about 1 wt%. The results of this study are expected to contribute to miniaturization, weight reduction and localization of avionic display and lighting devices.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.796-799
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• 2004

The effects of forming presure, organic binder content and moisture on flexural strength were investigated. As moisture content increased in the granules during compaction, the density and strength of the green body were increased. Green strengths were found to improve more strongly with increasing forming pressure in the case of using the granules of higher organic content. The sintered strength was the highest with the organic content of 0.2wt％ under all forming pressures.