• 대한기계학회논문집B
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• 제29권3호
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• pp.390-401
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• 2005

In this study, extinction limit extension of unsteady $(CH_{4}+N_{2})$/air diffusion flames was investigated experimentally. A spatially locked flame in an opposing jet burner was perturbed by linear velocity variation, and time-dependent flame luminosity, transient maximum flame temperature and OH radical were measured over time with the high speed camera, Rayleigh scattering method and OH laser-induced fluorescence, respectively. Unsteady flames survive at strain rates that are much higher than the extinction limit of steady flames, and unsteady extinction limits extend as the slope of the strain rate increases or the initial strain rate decreases. We verified the validity of the equivalent strain rate concept by comparing the course of unsteady extinction process and steady extinction process, and it was found that the equivalent strain rate concept represents well the unsteady effect of a convective-diffusive zone. To investigate the reason of the unsteady extinction limit extension, we subtracted the time lag of the convective-diffusive zone by using the equivalent strain concept. Then the modified unsteady extinction limits become smaller than the original unsteady extinction limits, however, the modified unsteady extinction limits are still larger than the steady extinction limits. These results suggest that there exist the unsteady behavior of a diffusive-reactive zone near the extinction limit due to the chemical non-equilibrium states associated with unsteady flames.

• 한국생물환경조절학회:학술대회논문집
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• 한국생물환경조절학회 2004년도 추계학술대회 논문집
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• pp.5-9
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• 2004

Garlic industries in Korea faced with a increasing difficulty because of the pressure of garlic importation from China is ever increasing than before. Therefore this study was conducted to produce low-cost garlics by mechanized cultivation and the results are as follows. A. By applying machinery(stem cutter and size separator, seeder, harvester) the labor was saved over 70% compare with the conventional cultivation B. Growth characteristics and yield showed no difference in mechanized and conventional cultivation of northern-type garlic. C. When scales were sown by seeder, the sowing-depth varied between 3 to 6cm and the rate of 2-plants emergence in one hole was 14.5%.

• 한국자원식물학회지
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• 제28권4호
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• pp.546-549
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• 2015

This study was carried out to investigate the effect of simple hydroponic culture in cultivation of grafted cactus. The results obtained are as follows: Growth indexes of grafted cactus cultivars, such as scion diameter, fresh weight, and scion hardness were improved in simple hydroponic culture compared with soil culture regardless of cultivars. Stem rot and rate of non-graft take were lower in simple hydroponic culture than in soil culture, but no significant difference was monitored between cultivars. Time for harvesting was fast in simple hydroponic culture compared with soil culture. Marketable yield increased in simple hydroponic culture.

• Structural Engineering and Mechanics
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• 제25권6호
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• pp.733-751
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• 2007

The metis element method (Hung 1978) has been applied to analyse free edge interlaminar stresses and delamination in composite laminates, which are subjected to extension and bending. The paper recalls Lekhnitskii's solution for generalized plane strain state of composite laminate and Wang's singular solution for determination of stress singularity order and of eigen coefficients $C_m$ for delamination problem. Then the formulae of metis displacement finite element in two-dimensional problem are established. Computation of the stress intensity factors and the energy release rates are presented in details. The energy release rate, G, is computed by Irwin's virtual crack technique using metis elements. Finally, results of interlaminar stresses, the three stress intensity factors and the energy release rates for delamination crack in composite laminates under extension and bending are illustrated and compared with the literature to demonstrate the efficiency of the present method.

• 한국약용작물학회지
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• 제22권3호
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• pp.210-216
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• 2014

The average and maximum temperature were $29.5^{\circ}C$ and $33.2^{\circ}C$ at 2:00 p.m. respectively, in the plastic-film house covered with shade net, and both of temperature were lower $0.6^{\circ}C$ and $1.3^{\circ}C$ than those of conventional shade. Light transmittance was 14% in the plastic-film house, while 9.9% in conventional shade during growing season from May to October. Withering time of aboveground part was on October 3rd in conventional shade with 60% of withering leaf, while it was on November 10th with 3.7% of withering leaf in the plastic-film house, about 40 days longer survival. The main disease incidence were 15% of anthracnose, 17% of leaf spot, 5% of phytophthora blight and 3% of gray mold in the conventional shade, while 0 ~ 0.1% disease incidence and 95% of emergence rate in the plastic-film house. The growth in the aboveground and underground part of ginseng was totally better, particularly characteristics affecting yield such as root length, main root length and diameter in the plastic-film house. The fresh weight was increased by 128% compared to the conventional shade and harvested roots per $3.3m^2$ were 36 roots in the conventional shade and 58 roots in the plastic-film house and futhermore yield per $3.3m^2$ was increased by 216% compared to the conventional shade. As covering materials, the rice straw in the plastic-film house was excellent. The ginsenoside contents affecting the quality of ginseng were higher in the plastic-film house indicating 0.333% of Rg1, 0.672% of Rb1, 0.730% of Rc and rate of red rusty root was less than 4.0 ~ 6.1%. Above the results, the quality of ginseng grown in the plastic-film house covered with shade net was improved than that of the conventional shade.

• 식물병연구
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• 제21권1호
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• pp.6-11
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• 2015

고추 탄저병 요방제 수준을 설정하기 이하여 시험한 결과 노지 고추 수량에 영향을 주지 않는 수준의 탄저병 방제적기는 발생정도가 0.9% 이하이었으며, 노지고추 탄저병 발생정도와 수량과의 회귀식은 Y = -16.83X + 327.57, $R^2=0.83$ 성립하였다. 비가림 재배(무강우 조건) 고추의 수량에 영향을 주지 않는 수준의 탄저병 방제적기는 발생정도가 1.7% 이하이었으며, 고추탄저병 발생정도와 수량과의 회귀식은 Y = -4.92X + 361.02, $R^2=0.84$ 성립하였다. 비가림 재배(강우 조건) 고추의 수량에 영향을 주지 않는 수준의 탄저병 방제적기는 발생정도가 2.3% 이하이었으며, 고추 탄저병 발생정도와 수량과의 회귀식은 Y =-5.91X + 359.71, $R^2=0.76$ 성립하였다.

• 식물조직배양학회지
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• 제26권1호
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• pp.65-69
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• 1999

LSV 제거 효과를 조사하기 위하여 LSV에 감염된 나리 Casa Blanca를 재료로 기내 배양 중에 화학약제 및 열처리를 단독 또는 병형처리하였다. 단독처리시 ribavirin 20 mg/L과 열처리 35$^{\circ}C$/$25^{\circ}C$ (주간/야간)에서 식물의 생육 및 LSV 제거율(각각 86%, 80%)이 ekfs 처리보다 좋았다. 이 두 처리를 병행하였을 경우, 열처리 기간이 길수록 LSV 제거율은 증가하는 경향이었으며, 열처리 16주의 모든 처리에서 ribavirin 농도와 관계없이 100%의 LSV 제거 효과를 보였다. 토양 정식 후 LSV 무병화 정도는 ribavirin 20 mg/L 농도와 열처리 8주 병행처리에서 12개체 중 8개체가 무병화를 보여 가장 효과적이었으며, 전체 조사 수를 기준으로 했을 때 약 21% 정도의 무병화가 유지되었고, 나머지는 토양의 자연 조건에서 다시 바이러스의 복제, 증식이 되는 것으로 보인다.

• 화훼연구
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• 제16권4호
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• pp.255-259
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• 2008

준고냉지에서 안개초 'Bristol Fairy'를 실험재료로 이랑높이를 10, 20, 30, 40 cm로 하여 토양 물리성, 생육 및 개화특성 등을 조사하였다. 주간 지온, 토양 수분함량, 토양 경도, 용적밀도 및 고상률은 이랑이 높을수록 낮고, 공극률은 약간 높아지는 경향이었다. 여름과 가을 절화작형에서 30 cm, 40 cm 이랑에서 개화는 약간 지연되었으나, 뿌리활력, 화수폭과 절화량은 우수하였다. 여름을 경과하면서 발생한 고사주율 및 로젯트 발생률, 비원추화서률 등 생리장해 발생도 낮아지는 경향이었다.

• 한국식품영양학회지
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• 제33권6호
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• pp.672-680
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• 2020

This study was conducted to effectively supplement vitamin D and increase the consumption of ear mushroom based on the investigation of the quality characteristics of cookies containing ear mushroom supplemented with vitamin D. Cookies were made of 0%, 1%, 3%, and 5% ear mushroom powder treated by ultraviolet B. Increased addition of ear mushroom powder led to a decrease in the bulk density of the dough as well as a spread factor, color value, and hardness of the cookies. There was no significant difference in the loss rate, but the water content of the dough and cookies was increased. The total polyphenol content of cookies added with 1~5% ear mushroom powder was higher than that of the 0%. The DPPH free radical scavenging activity of cookies added with 5% ear mushroom powder (23.8%) was 2 times higher than that of the 0% (10.9%). The vitamin D2 content of cookies added with 5% ear mushroom powder (835.5 ㎍/100 g D.W.) was 44 times higher than that of the 0% (19.0 ㎍/100 g D.W.). Consequently, ear mushroom powder is considered to be suitable for the production of functional cookies because of high values of antioxidant activity and vitamin D2 content.

• 한국식품영양학회지
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• 제36권2호
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• pp.114-121
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• 2023

The objective of this study is to evaluate the antioxidant components, elastase inhibition activities, and melanin synthesis rates of Korean traditional Actinidia (Actinidia arguta) fruits and leaves depending on the ethanol extraction concentrations. The total polyphenol content was the highest in the 50% ethanol extract of both fruits and leaves, with values of 634.1 mg GAE/100 g and 3,985.2 mg GAE/100 g, respectively. The total flavonoid content was the highest in the fruit 90% extract and leaf 50% extract at 191.9 mg/100 g and 2655.6 mg/100 g, respectively. The vitamin C content was the highest in the 50% extract of leaves at 2990.3 mg/100 g. Elastase inhibition was the highest at 56.9% in the leaf 50% extract at a concentration of 1,000 ㎍/mL. Melanin synthesis inhibition showed the highest melanin synthesis inhibitory effect among the extracts, as the leaf 50% extract showed an inhibitory rate of 65% or more. Therefore, the antioxidant components, elastase inhibition activities, and melanin synthesis inhibitory rate were better in leaves than in fruits. The leaf 50% extract was particularly the best among the extracts. Korean traditional Actinidia leaves can be considered as potential sources for new functional materials.