• 한국작물학회지
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• 제50권1호
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• pp.55-59
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• 2005

Rice farmers can save labor and expenses by using expanded rice husk (ERH) as a seedling medium since ERH is lighter and cheaper than other commercial seedling media (CSM). This study was carried out to develop a method for rice seedling cultivation using ERH as a seedling medium. It is suggested that a mixture of $60\%$ of ERH and $40\%$ of a CSM could be used as a seedling medium; the planting densities would be 240g per tray for infant seedlings and 200 g for young seedlings; and nitrogen (N) would be applied at a rate of 1g per tray for infant seedlings prior to planting and 2g per tray for young seedlings with division. Great care should be taken to use $CO(NH_2)_2$ as an N-source fertilizer. These results would lay a foundation for the rice seedling cultivation with ERH as a medium.

• 농촌지도와개발
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• 제10권2호
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• pp.211-227
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• 2003

According to the TRQ system created by WTO agreement on agriculture, Korea notified the WTO of the application of tariff rate quotas for 67 agricultural commodities(now, 63 commodities). Among these government administrate state-operated trade for 17 commodities. However, WTO/DDA negotiation will bring about lowering tariffs and increasing quantities of tariff quota. This study suggest the development programs corresponding WTO/DDA agriculture negotiation. First, from the viewpoint of the protection of domestic agriculture & improving transparency of agricultural import administration, the administration system of the state-operated trade will be necessary to be transformed for market oriented methods. Second, the administration system of the state-operated trade will be necessary to be rendered unified organization also. The current system of the state-operated trade shows the phenomena og many divergency. And third, The quantities of market access of FTA between Korea and Chile will be desirable to be administrate by state-operated trade. Because, according to diffusion of FTA treaties, the amount of market access quantities of FTA increase rapidly henceforth.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 추계학술대회 논문집
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• pp.424-442
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• 2005

In this paper a design of a large shield Tunnel through weathered soil and weathered rock in 703 section of seoul subway line No.7 extension project is presented. The geological investigation results show that the projecet region consists mostly of weathered soil with some local weathered rock in the tunnel excavation level. A EPB shield TBM is selected as a optimal excavation machine for the large shield Tunnel considering the geological and site conditions. Also, the shield machine head and cutter for the large shield tunnel type are designed considering site geological conditions and average advance rate in similar projects.

• 한국자원식물학회지
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• 제24권6호
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• pp.696-701
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• 2011

The aim of this field experiment was to investigate the possible effects of mepiquat chloride (TE) and trinexapac-ethyl (MC) on oil composition, seed yield and endogenous gibberellins content of flax cultivar. Foliar application of plant growth retardants mepiquat chloride (0.897, 1.794 and 2.691 kg a.i. $ha^{-1}$) and trinexapac-ethyl (0.756, 1.512 and 2.668 kg a.i. $ha^{-1}$) had significantly increased seeds ripening rate and seed yield. In contrast, plant height was decreased by foliar application of MC and TE. The application of MC significantly increased seed oil yield (730 kg $ha^{-1}$ by 27.0%) compared to the control. Seed and oil yield, and unsaturated fatty acids (oleic acid, linoleic acid and linolenic acid) were increased by foliar application of MC.

• International Journal of Automotive Technology
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• 제8권2호
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• pp.219-224
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• 2007

Recently, atmospheric contaminations has become worse due to the increased number of automobile. The PCV (Positive Crankcase Ventilation) valve acts as a flow control to allow re-combustion of blow-by gas by having it flow from a crankcase to an inlet manifold suction tube. Also, during the fabrication of the PCV valve, micro cracks may occur in the valve body and be extended under operation. The excessive stress distribution and crack initiation on the PCV valve body would bring an unstable blow-by gas flow rate control and would cause valve failure. The purpose of this study is to examine the crack affects on the stress and strain variations on the PCV valve according to the inlet and outlet manifold under differential pressures. From the results, we can explain the behavior of the crack extension for a safe condition of PCV valve.

• 한국안전학회지
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• 제29권1호
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• pp.31-36
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• 2014

In this study, the methodologies for evaluating the low-flow at the ungauged watershed are reviewed and assessed. The ungauged watershed can be classified into different situations such as the partially recorded watershed and the completely ungauged watershed. The extension method and the percentile method are used to evaluated the low-flow at the partially recorded watershed. The drainage-area ratio method and the regional regression method are used at the completely ungauged watershed. These four methods are applied and validated based on the hydrological and geometric data acquired from unit watersheds in Han River basin for TMDLs. In case of partially recorded watershed, the values of low-flow evaluated by the extension method are in better agreement with measured flow-rate rather than those by the percentile method. In case of completely ungauged watershed, the drainage-area method is broadly used to estimate the low-flow. It must be paid attention to consider the treated sewage discharge produced at watersheds when applying the method.

• 한국지반공학회논문집
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• 제35권12호
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• pp.35-44
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• 2019

본 연구에서는 수직증축 공동주택 하부 신설 보강말뚝의 축강성(K_vr)을 기존말뚝의 열화를 고려한 이론적인 접근과 수치해석을 통하여 산정하였다. 3차원 유한요소 수치해석을 수행하는 과정에서, 이론적인 접근과 38본의 시험 말뚝계측 결과를 통하여 제안된 열화를 고려한 기존말뚝 축강성(K_ve)의 상한 값을 적용하였다. 이를 통해, 수직증축 리모델링으로 인하여 증가된 하중을 안정적으로 지지하기 위한 신설 보강말뚝의 최소 축강성을 산정하였다. 신설 보강말뚝의 축강성 제안은 선단지지 말뚝과 마찰말뚝에 대해 수행하였고, 다양한 세장비(L/D)에 따라 제안하였다. 해석기법은 기존말뚝의 설계 당시의 양호한 상태를 고려한 말뚝지지 전면기초 거동 해석과 열화가 고려된 기존말뚝의 축강성을 적용한 말뚝지지 전면기초 거동 해석을 수행하였다. 두 해석기법에 대한 검증을 수행한 결과 말뚝지지 전면기초 거동해석이 가능한 것으로 확인되었고, 이를 통하여 기존말뚝의 열화가 발생하였을 때 선단지지 신설 보강말뚝 축강성이 44 - 67% 증가되어야 수직증축 구조물의 안정성이 확보됨을 알 수 있었다.

• 한국초지조사료학회지
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• 제20권3호
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• pp.161-168
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• 2000

The experiment was carried out to investigate the effect of extension of grazing duration in late autumn on grass growth in following spring, in order to improve the rate of self-sufficiency for roughage feed. Plant height, total biomass and litter production of herbage were increased when the grazing was finished early in late autumn. The proportions of clover and litter, and amounts of animal intake were decreased, with extended grazing duration in late autumn. But when the grazing was finished late in autumn, the contents of crude protein (CP, %) of herbage were increased, contents of acid detergent fiber (ADF, %), neutral detergent fiber (NDF, %) and crude ash (%) were decreased in pasture after grazing, therefore the contents of total digestible nutrients (TDN, %) and relative feed value (RFV) of herbage were improved. The early end grazing showed that plant height, total biomass and litter production of herbage in following spring were higher than those in late end grazing. However, increased yields were not significantly different among end grazing treatments (0.12-0.15 tonha), except for the final end grazing in late autumn (0.01 tonha). With extended grazing duration in late autumn, the contents of CP of herbage in following spring were increased, contents of ADF, were decreased, and RFV were improved. (Key words : Extension of grazing duration, Plant height, Biomass, Amount of intake, Increased yield, Crude protein, TDN) rll\ulcorner c# qiil x i 9 ~ 1 a% * (College of Natural Resources, Taegu Univ., Kyongsan, 71 2-714, Korea) * $4 4 qiil 34 qq(Co1lege of Liberal Arts & Sciences, Yonsei Univ., Wonju, 220-701, Korea) '* 8 * jL@%ft@ &@%(Faculty of Agriculture, Hokkaido Univ., Sapporo, 060 Japan)

• 생약학회지
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• 제45권4호
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• pp.275-281
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• 2014

After harvesting the medicinal parts of Curcuma longa, the remaining underground parts were discarded. From the remaining underground parts of Curcuma longa quercetin-3-O-${\beta}$-D-glucopyranoside-7-O-${\alpha}$-L-rhamnopyranoside (Q37) was isolated. The antioxidant activities in vitro and lifespan-extension effect of Q37 were elucidated using the Caenorhabditis elegans. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging effect of Q37 showed similar potent activities in comparison with vitamin C. Q37 also showed potent superoxide quenching activities as measured by the riboflavin- and xanthine-originated superoxide quenching activity tests. Q37 prolonged lifespan of worms under normal culture condition. In terms of protective effect of Q37 on the stress conditions such as thermal and oxidative stresses, Q37-treated worms exhibited enhanced survival rate, as compared to control worms. To know the possible mechanism of Q37-mediated increased lifespan and stress resistance of worms, we examined the activities of Q37on superoxide dismutase (SOD), and invested intracellular reactive oxygen species (ROS) levels. The results revealed that Q37 was able to elevate SOD activity of worms and reduce intracellular ROS accumulation in a dose-dependent manner.

• 한국식품저장유통학회지
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• 제13권3호
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• pp.279-284
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• 2006

저장방법에 따른 삼백초 생근경의 품질과 유효성분 함량의 변화를 조사하였다. 감모율과 부패율 및 맹아수는 저장기간이 경과할수록 증가하거나 많았다. 감모정도와 맹아수는 저온저장에서 가장 적었으며, 부패율은 창고 내 흙 충진 저장에서 낮았다. 삼백초 근경의 chromatogram상 각 성분의 머무름시간(RT)은 $18{\sim}36$분대로 saucernetin>sauchinone>manassantin A>saucerneol D>manassantin B의 순으로 나타났다. Lignans의 함량은 저장방법 모두 저장 후 30일에 비해 120일에 낮았으나, 저장방법간에는 차이가 없었고 manassantin B>manassantin A>saucernetin>sauchinone>saucerneol D의 순으로 함량이 높았다.