• Fire Science and Engineering
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• v.22 no.2
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• pp.57-62
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• 2008

Most of all the Korean home use a wallpaper as a decoration and finishing of interior. One of the fire spread factor in a house is a combustion of wall paper. There were some research concerning oxygen index in a ambient temperature. The purpose of this study is to investigate the difference of oxygen index of a wallpaper between ambient and high temperature and a effect on the fire spreading. Based on the result, the difference of oxygen index between ambient temperature and high temperature showed $5{\sim}8%$. Difference of 0.1% of oxygen index show big differences in combustion length of sample. Therefore, it was found that the decrease of oxygen index at elevated temperature is a important factor in fire spread.

• Korean Journal of Plant Resources
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• v.19 no.2
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• pp.273-276
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• 2006

Lipid-lowering and antioxidant effects of Poncirus trifoliata extract were investigated in hyperlipidemic rat. Concentrations of FFA and triglyceride in plasma were decreased in Poncirus trifoliata extract treatment groups. Plasma total cholesterol and LDL-cholesterol were lower in Poncirus trifoliata extract treatment groups. However HDL-cholesterol showed no significant difference in all treatment groups. Concentrations of liver total cholesterol and triglyceride were decreased in Poncirus trifoliata extract treatment groups. Concentrations of plasma and liver TBARS showed a low values in Poncirus trifoliata extract treatment groups. The values of GSH-Px and CAT activities were increased in the Poncirus trifoliata extract treatment groups. However the values of SOD activity showed no significant difference in all treatment groups.

• Journal of Korean Tunnelling and Underground Space Association
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• v.4 no.2
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• pp.91-100
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• 2002

This paper presents the results of laboratory investigation on the deformation behavior of tunnel face reinforced with longitudinal pipes. A series of reduced-scale model tests was carried out to investigate the effect of reinforcement layout on the tunnel face axial displacement as well as the surface settlement. Among other things, the results of the model tests indicate that the axial displacement of tunnel face as well as the ground surface settlement can significantly be reduced by pre-reinforcing the tunnel face with longitudinal pipes, suggesting that the pre-reinforcing technique may effectively be used as a positive ground control method in the urban environments. Also illustrated is that the reinforcing effect is significantly influenced by the reinforcement layout. The implications of the findings from this study are discussed in a great detail.

• The Transactions of the Korean Institute of Power Electronics
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• v.6 no.2
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• pp.191-201
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• 2001

Recently, the demand of motor for industrial, household machinery is increasing. As Switching devices and control technology are progressing, so the use of BLDC Motor is increasing. But 3-Phase BLDC Motor generally used has pulsating torque and speed variation in commutation, so the range of its application is limited to high speed operation. Especially, to solve these problems, it is necessary to increase phase of Motor, so study of Poly-Phase BLDC Motor is progressing. However, when hysteresis current controller is used, switching frequency is highly increasing. In this paper, 7-Phase BLDC Motor drive system is designed. Also MSTC(Minimum Switching Time Controller) is proposed and with simulation and experiment, there validities are verified.

• Horticultural Science & Technology
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• v.18 no.6
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• pp.792-796
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• 2000

The staking cultivation (SC) of oriental melon (Cucumis mela L. var. makuwa Mak.) produced more fruit yield than that of the conventional (creeping) growing. In the SC, preharvest fruit drop rate was high as 47.6% compared to 13.0% of the conventional cultivation. However, the foliar application of aminoethoxyvinylglycine (AVG, $100mg{\cdot}L^{-1}$) at 2 weeks after flowering (20 days before harvest) greatly reduced fruit drops up to 10.9% without causing any effects on ripening and quality of fruits . The AVG application markedly suppressed ethylene production in harvested fruits.

• Journal of the Korea Society for Simulation
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• v.22 no.2
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• pp.33-40
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• 2013

This paper explores a border security system based on agent-based modeling and simulation (ABMS). The ABMS software platform, map aware non-uniform automata, is used to model various scenarios and evaluate the border security system given a set of infiltrators who have evolutionary behavior governed by genetic algorithm (GA). we formulated an optimization model and approximately solved it using a GA in order to capture near optimal behavior of an infiltrating force. The results presented give two significant insights for our border security system in that optimizing the infiltrator's behavior can make a significant difference and the quantitative results regarding the infiltrator's avoidance of each asset can be viewed as capturing their relative importance.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.9
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• pp.718-726
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• 1998

J-E 특성 AC 임피더스 분석 그리고 주파수- 전도 특성들을 실험하여 임펄스 전류 서지가 ZnO 바리스터의 열화(degradation)에 미치는 영향을 고찰하였다. ZnO 바리스터 시편에 임펄스 전류(300A/$cm^24, 8/50$\mu s$)를 인가시킨 결과, 입계(grain boundary) 특성을 나타내는 비선형계수 $\alpha$와 E\ulcorner\ulcorner의 값은 크게 감소하였으나, 입자 특성을 나타내는 E_{100A}, E_{300A}$ 값에서는 큰 변화가 없었다. 이러한 열화 현상은 입계의 위치한 부성 전하 밀도, $N_s$의 감소에 한 쇼트키 장벽의 변화에 기인한 것으로 나타났다. 임펄스 서지에 의해 열화된 ZnO 바리스터는 AC 임피더스 분석에서 현저한 non-Debye 특성을 보이며, 이는 병렬 RC 네트워크로 모델링한 Cole-Cole 완화 관계식으로 입계의 열화 특성을 잘 설명할 수 있었다. 주파수-전도도 관계를 검토한 결과 Zno 바리스터는 호핑 전도(hopping conduction),\$sigma(\omega)\varpropto\omega^{\eta}$ 특성을 나타내면, 임펄스 서지가 인가된 이후 n 값이 감소하였다. 이는 임펄스 서지에 의해 입RP 결합 상태(defect states)가 호핑 전도가 발생하기 쉽고 다중(multiple)호핑에 의한 전도 메커니즘을 갖는 것으로 고찰되었다.

• The Journal of the Korean dental association
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• v.14 no.3
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• pp.285-295
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• 1976

항암 화학요법제의 하나인 5-Fluorouracil 이 과상돌기의 성장에 미치는 영향을 연구하기 위하여 20두의 백서를 반씩 나누어 실험군에는 동약물을 체중 kg당 25mg씩 2일간 복강내주사하고 대조군에는 생리식 염수를 주사한 후 각각 제1,3,7,14 및 21일에 두 마리씩 도살하여 과상골디연골부의 조직학적 변화를 관찰하였다. 또한 도살 2시간 전에 5μCi/kg mM 의 ³H-thymidine을 주사하여 표본의 일부는 자기방사법적으로 처리 관찰 하였다. 관찰 결과는 다음과 같다. 1. 과상돌기 연골부의 후경에 상당한 감소가 일어났으며 제7일에서 가장 현저하였다. 2. 이러한 영향은 연골제거대와 세포증식대에서 가장크고 그 다음이 비대층이었다. 3. 제 7일의 변화 증식대엣는 기질 호 염색성의 증가, 핵 형태의 난원형화가 오고 소와내의 세포수는 1~2개였다. 비태층의 소와는 현저하게 작아지고 기질의 호염기성이 뚜렷하며 세포의 배열은 츹어지고 약간의 핵은 그 배 열이 불규칙하며 숫자고 대조군보다 적었다. 4. 위와같은 변화는 제 14일에서 감소하고 점차 회복적인 조직소견을 보여 제21일에는 성장이 거의 대조군에 근접한 조직상을 보였다. 5. 자기방사법적으로 세포증식대 및 연골제거대에서 세포분열에 대한 억제효과를 관찰한 바 제 7일 에서 가장 시하였고 특히 연골제거대에서 심하였다. 대체적으로 자기방사법적 관찰소견은 조직학적 소견과 일치하였다. 결론적으로 하악골 과상돌기의 성장은 5-Fluorouracil의 영향하에서 세포의 증식 및 분화상태로 보아 일정기간동안 저해되며 제 7일의 극기를 지나 점차 회복되어감을 나타내었다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.6
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• pp.1806-1810
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• 2008

Thirty five AD patients were treated with Phellinus linteus grown in germinated brown rice(PB) p.o., at 6, 9, and 12 g/day to the patients with their body weight for 12 weeks. A significant reduction in mean severity scores and mean symptom scores was observed after PB treatment. The mean SCORAD indices pre and post PB treatment were $31.28{\pm}10.01$ and $22.39{\pm}15.59$ (p<0.05), respectively. And the mean symptom score of pruritus assessment decreased from $7.37{\pm}1.33$ to $4.6{\pm}2.34$ (p<0.05) after PB treatment. These results suggest that PB shows alleviation of atopic dermatitis symptoms.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.2
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• pp.121-124
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• 1981

The panicle enclosing Gamadi rice cultivar from western Tarai of Nepal was treated with different daylengths; 8 hours, natural daylength i.e. 14 hours 30 minutes to 12 hours 30 minutes, and 24 hours throughout its life cycle. The extremely long daylength of 24 hours induced the panicle exsertion, and elongated the first internode from the top, but did not affect the second internode significantly, suggesting that the panicle exsertion was strongly correlated with the first internode elongation in the Gamadi rice cultivar.