• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.923-931
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• 2008

Coupling rubber pad are important components in railway vehicles. It can be used for reduce shock, vibration and noise. Simple tension, equi-biaxial tension and pure shear test were performed to acquire the coefficient of rubber material which were Mooney-Rivlin and Ogden model. The finite element analysis was executed to evaluate the behavior of deformation and stress distribution by using the commercial finite element analysis code. Useful life evaluation are very important in design procedure to assure the safety and reliability of the rubber components. In this paper, useful life prediction of rubber pad for railway vehicle were experimentally investigated. Accelerated heat-aging test for rubber material were carried. Compression set results changes as the threshold are used for assessment of the useful life and time to threshold value were plotted against reciprocal of absolute temperature to give the Arrhenius plot.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.104-111
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• 2006

The non-linear properties of rubber material which are described as strain energy function are important parameter to design and evaluate of rubber spring. These are determined by material tests which are uni-axial tension and bi-axial tension. The computer simulation using the nonlinear element analysis program executed to predict and evaluate the load capacity and stiffness for chevron spring. In order to investigate the heat-aging effects on the rubber material properties, the acceleration test were carried out. Compression set results changes as the threshold are used for assessment of the useful life and time to threshold value were plotted against reciprocal of absolute temperature to give the Arrhenius plot. By using the compression set test, several useful life prediction for rubber material were proposed.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.375-380
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• 2009

Gas & Oil plant construction projects are increasing recently all over oil-producing countries. An EPC (Engineering, Procurement and Construction) company, which participates in the plant projects, should possess pertinent engineering licenses and EPC management skills to create high added-value. Nonetheless, there exist various risks involved in the EPC life cycle process due to such characteristics of construction projects as long duration of construction time and complicated processes along with the procured goods or services subjected to various logistics. The objective of this paper is to analyze the overall EPC life cycle for proper process and to examine various information and document. Additionally, the principal data for the analysis of the EPC process are derived from personal interviews with experts and specialty contractors of the plant projects. The results of this study would be widely used as a guide for efficient and effective management of overseas gas plant projects.

• 한국식품과학회지
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• 제20권5호
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• pp.637-643
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• 1988

대두유를 튀김유로 사용하여 french fried potato를 $185^{\circ}C$에서 제조하면서, 1일 7시간씩 총 56시간동안 가열 및 튀김후 composited powder (citric acid, 물, rhyolite 혼합물)를 처리한 대두유와 처리하지 않은 대두유의 기능성, 발연점, 기포성 및 점도와 물리화학적 성질을 비교 분석하였다. Composited powder를 처리하면 극성지질의 생성을 억제하고, 불포화 지방산의 가열산패를 억제시켜, 튀김유의 수명을 약 50% 증가시켰음을 확인하였다. 그러나 산가증가의 억제 및 발연점 저하의 효과가 없었다.

• 펄프종이기술
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• 제43권3호
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• pp.73-79
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• 2011

The annals of Joseon Dynasty is one of the UNESCO's Memory of the World Register. For the safety preservation of wax applied volumes of the annals of Joseon Dynasty, the aging behavior of beeswax and beeswaxed Hanji with $CO_2$, $O_3$, $SO_2$ and $NO_2$ gas has been evaluated. The weight loss of beeswaxed Hanji after aging under ozone gas were increased because of strong acidity of ozone. The acid value and relative intensity of carbonyl groups in beeswax were stabilized with aging time. The physical strength of dewaxed Hanji after ozone aging were rapidly decreased by aging time. The crystallinity of dewaxed Hanji were stabilized at all aging times.

• 한국융합학회논문지
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• 제9권7호
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• pp.309-315
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• 2018

삶의 방식 및 환경의 변화로 생활체육의 수요가 증가하고 있으며 해양스포츠 활동의 기회확대로 인해 해양스포츠인구도 빠르게 증가하고 있다. 이에 본 연구는 해양스포츠가 가지고 있는 생활체육으로서의 가치를 문헌연구를 통해 탐구하였다. 탐구 결과, 해양스포츠는 여가만족, 복지기능과 같이 생활체육이 가지고 있는 삶의 질 향상을 위한 도구로서의 기능적 가치를 포함하고 있으며 개인의 삶에 긍정적인 영향을 미칠 뿐만 아니라 나아가 사회적 행복수준을 높이는데 기여할 수 있다. 또한, 해양스포츠는 자연을 활용한 직접경험 신체활동으로서 인간이 자연을 이해하는데 중요한 기능을 가지고 있으며 특히, 비현실적 여가활동이 대부분을 차지하고 있는 현대사회의 청소년들에게 올바른 인격을 형성시킬 수 있는 정서 교육적 가치가 높다는 것을 확인할 수 있었다. 이는 해양스포츠가 생활체육이 가지고 있는 다양한 가치 이상의 긍정적 가치들을 내포하고 있으며 생활체육으로서의 충분한 가치가 있음을 의미한다고 할 수 있다.

• Journal of Plant Biotechnology
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• 제39권1호
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• pp.62-68
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• 2012

The vegetable brassicas are an important crop worldwide and are of significant commercial value. In order to ensure our targets for food security are met it is important that these crops are continually improved to increase sustainability of production, increase nutritional quality and reduce waste. Development of resistances against both biotic and abiotic stress are recognised as being key. Plant breeding plays a vital role in addressing these issues through the development of new and improved varieties. This continued improvement is becoming evermore dependent on our ability to identify and introgress beneficial alleles from 'exotic' germplasm into elite breeding material. Increasingly, more diverse germplasm such as those found in genebanks is being screened for benificial allelic variation, however, plant breeders often find it difficult to make use of such material due to the time required to remove undesirable characteristics from progeny due to linkage drag. This article describes how we have attempted to overcome this and develop resources that make the diversity available within the $Brassica$ $oleracea$ genepool more accessible.

• 한국압력기기공학회 논문집
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• 제10권1호
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• pp.64-69
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• 2014

Gr. 91 steel is used for the major structural components of Generation-IV reactor systems, such as a very high temperature reactor(VHTR) and sodium-cooled fast reactor(SFR). Since these structures are designed for up to 60 years at elevated temperatures, the prediction of long-term creep life is important for a design application of Gr. 91 steel. In this study, a number of creep rupture data were collected through world-wide literature surveys, and using these data, the long-term creep life was predicted in terms of three methods: the single-C method in Larson-Miller(L-M) parameter, multi-C constant method in the L-M parameter, and a modified method("sinh" equation) in the L-M parameter. The results of the creep-life prediction were compared using the standard deviation of error value, respectively. Modified method proposed by the "sinh" equation revealed better agreement in creep life prediction than the single-C L-M method.

• Asian Pacific Journal of Cancer Prevention
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• 제15권6호
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• pp.2803-2807
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• 2014

Bioassay-guided chemical investigation of the roots of Anthriscus sylvestris (L.) Hoffm. resulted in the isolation of nine compounds, whose structures were determined by spectroscopic methods. Compound 1 was isolated from this plant for the first time and compounds 3 and 9 were first found from this genus. Different polar fractions of A. sylvestris extract and compounds 1, 6-8 and 9 were evaluated for antitumor activities against HepG2 (human hepatocellular carcinoma), MG-63 (human osteosarcoma cells), B16 (melanoma cells) and HeLa (human cervical carcinoma cells) lines by the MTT method. The petroleum ether fraction of A. sylvestris extract exhibited excellent inhibitory activity with an $IC_{50}$ value of $18.3{\mu}g/ml$. Among the isolates from the petroleum ether fraction, compound 7 showed significant inhibition against the growth of the four tumor cells with $IC_{50}$ values ranging from $12.2-43.3{\mu}g/ml$.

• 한국식품영양과학회지
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• 제28권4호
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• pp.786-793
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• 1999

To investigate the effects of medicinal plants on the shelf life of kakdugi, various kakdugies, added with hot water extract from 62 natural plants, were fermented at 20oC for 15 days. In case of control without the addition, the shelf life required to reach the acidity of 1%(as lactic acid) was 7 days. Morethan two fold extension of shelf life was observed with twenty seven extracts, of which six extracts maintained the hardness of kakdugi higher than that of control over the entire fermentation time. And the number of lactic acid bacteria in above kakdugies was not remarkably different from that of control, and the color(a value) of the liquid of kakdugi, added with Chaenomeles lagenaria, Moringa oleifera, Peaonia lactiflora or Citrus tangerina extract, was similar to that of control. In sensory test, the extracts from the above plants except Moringa oleifera were found to be acceptable. It is suggested that the addition of above three extracts may lead to extension of shelf life of kakdugi, based on the acidity, hardness, color and sensory test.