• International Journal of Highway Engineering
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• v.6 no.4 s.22
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• pp.75-89
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• 2004

Long term performance of concrete pavement significantly depends on the given construction and environmental condition. It means that random cracks and extreme crack width due to inappropriate quality control at the early age might lead to decreasing the pavement service life. The temperature and moisture during the construction, cement and aggregate types, curing condition are major components to affect the quality of the concrete pavement at the early age. First of all, the high temperature differential, that is made by increasing air temperature and the heat of cement hydration, is known as the major contributor to severe cracks. In this study, tent covering was used for controlling temperature of the concrete slab. The field measurement data indicates that the effect of the tent covering is very significant to decrease possibilities of random crack occurrence and curling stress and enhance the long-term concrete strength. HIPERPAV(High PERformance PAVing software), a program predicting the strength and stress of an earty-age concrete pavement (72 hour after placement), is used for simulating the effects of tent covering. The HIPERPAVE results showed that the section with the tent covering has higher reliability than the section without the tent covering by 22.5%. In details, reliability is increased 72.5% (without the tent covering) to 95% (with the tent covering).

• Korean Journal of Medicinal Crop Science
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• v.13 no.4
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• pp.133-137
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• 2005

Experiments were conducted to find the optimal acclimatization conditions for Eleutherococcus senticosus plantlets regenerated from bioreactor cultured somatic embryos, various acclimatizing conditions were compared regarding both survival rate and growth of the plantlets. Among the various temperature and artificial soil tested, the highest survival rate (88%) was observed when plantlets were acclimatized in Klasmann bed soil at $10^{\circ}C$ When in vitro plantlets directly transplanted to field environment, shading treatment was necessary and 50% shading was more effective than 30% shading. Transplanting season were also important for successful acclimatization of in vitro cultured plantlets, transplanted on March 20 with 50% shading exhibited the best survival rate and further growth.

• Journal of Bio-Environment Control
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• v.25 no.4
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• pp.320-327
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• 2016

Allium hookeri is used for food and medical materials in Asia. This study was carried out to elucidate the effects of shading rates on growth and quality of A. hookeri cultivation in greenhouse. Treatments were given with 35%, 55%, 75% and 95% shading rates and non-shading (Control). Photosynthesis photon flux density (PPFD) of control, 35%, 55%, 75%, and 95% shading were 792, 515, 351, 182, and $78.2{\mu}mol{\cdot}m{\cdot}s^{-1}$ respectively. The emergence ratio was 98% under non-shading, 35% and 75% shading condition, and it was 100% under 55% and 95% shading condition on April 20, 2016. These results showed no correlation between emergence rate and shading treatment. When shading net was set up inside at greenhouse, fresh weights in control, 35%, 55%, 75%, and 95% shading treatments were 1,142, 3,511, 5,936, 6,408 and 3,779kg/10a, respectively. When shading net was set up outside at greenhouse, fresh weights in control, 55%, 75%, and 95% shading treatments were 1,372, 5,442, 6,238 and 3,595kg/10a, respectively. Dry weight, percentage of dry matter, number of leavesand branches, plant height and root length in 75% shading treatment were higher than other shading treatments. From these results, we suggested that the proper shading rate in a greenhouse is 75% for A. hookeri cultivation in middle area of Korea.

• 월간낙농육우
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• v.36 no.9
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• pp.145-148
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• 2016

올 여름은 한 달이 넘도록 열대야가 지속될 정도로 가히 '살인적' 더위였다. 폭염으로 인한 고온 스트레스는 젖소들에게 단순히 산유량 저하뿐만 아니라, 다가오는 가을철에 수태율을 감소시키고 대사성 질병 면역력을 떨어뜨려 큰 피해를 준다. 이에 농가들은 고온 스트레스를 최소화하기 위해 차광막을 설치하거나 지붕에 스프링클러를 분사하는 등 하루하루 긴장 속에 이 계절을 보내야 했다. 하지만 올해 같은 폭염 속에서도 차광막 하나 없이 축사를 관리한 농가들이 있었다. 바로 'P.C(폴리카보네이트, Poly-Carbonate) 다기능 지붕재 엠보(이하 P.C엠보)'를 설치한 목장들이다. 직사광선의 피해를 최소화할 수 있는 'P.C 다기능 지붕재 엠보'를 개발한 (주)대한철강(대표 김상국)을 찾아가 봤다.

• Journal of Bio-Environment Control
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• v.15 no.4
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• pp.306-316
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• 2006

In this study, the effect of the shade level, water flow rate applied to the shades and the temperature of water on the greenhouse cooling was investigated depending on the shade level of 0, 35, 55, 75%, and water flow rate and water temperature by the test on the small wooden frames to find out the low cost cooling method. With increasing of the dry bulb temperature of outside air, the dry bulb temperature in the wooden frames increased. For the frames with the shade and water, inside temperatures of the frames were lower of -0.2$\sim$-1.2$^{\circ}C$ than the temperature of the outside air and higher than the water temperature. For the frames without water, inside temperatures of the frames were higher of 1.7$\sim$4$^{\circ}C$ than the outside and not affected by the shade level very much. The water flow rate and the temperature of the water were not the important factors to decrease the inside temperatures in the frames. The black globe temperature became lower with increasing of shade level. The shade frames with water curtain showed the best cooling effect because of reducing thermal radiation and cooling the plastic film cover. The surface temperatures of the plastic film cover for the water supplied modules became lower with increasing of the shade level. The relative humidity was decreased with the dry bulb temperature in the frame increasing and not affected by the dry bulb temperature of the outside air for the frames with the shade and water.

• Asian Journal of Turfgrass Science
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• v.15 no.2
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• pp.51-64
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• 2001

Summer stress is one of the serious problems on cool-season grass at the soccer fields in Korea during heavy rainy season. This study was conducted to intestigate the effect of shade net with regard to its percent (0, 50, 75), color (black, green), height (0 cm, 30 cm) and time (7 hr, 24 hr) on turf canopy temperature, light intensity, leaf color, turf performance, clipping yield and root dry weight of cool-season turfgrass. Turf canopy temperature was 6~13$^{\circ}C$ under black and green shade net when temperature was over 4$0^{\circ}C$. Light intensity was also decreased from 40 to 94% under black and green shade net compared to control. Black shade net was more effective than green net in reduction of temperature and light intensity. Green shade net was found to be better for photosynthesis of cool-season grass. Leaf color, turf performance, clipping yield, and root dry weight were better and increased under 50% and 75% shade net. 50% black shade net with 30cm height and 7 hr treatment showed the best turf performance. It can be concluded that 50% and 75% green shade net can be used fur reducing summer stress on cool-season grass after soccer marches during heavy rain season. The shade net decreased the turf canopy temperature and reduced heating damage of cool-season turfgrass.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2000.10a
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• pp.22-25
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• 2000

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2003.09a
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• pp.73-76
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• 2003

약용식물로 널리 알려진 가시오갈피는 해발고 900m내외의 서늘한 지역에서 토양이 비옥하고 습기가 많은 활엽수림에 자생하며, 높은 광도와 기온을 나타내는 입지환경에서는 거의 찾아볼 수 없는 것으로 알려져 있다(박문수 등, 1996). 이러한 생육특성 때문에 인공재배를 하는 경우, 차광막을 사용하여 일정량의 빛을 차단하면 전천광을 모두 수광한 것에 비해서 높은 생장을 나타낸다고 한다(한종수 등, 2001).(중략)

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2000.10a
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• pp.26-29
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• 2000

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.12a
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• pp.66-66
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• 2020

쌈채소나 산나물로 알려진 곤달비(Ligularia stenocephala)의 종자나 종묘는 시장 거래가격이 높게 형성되어 재배농가의 경영비 증가로 이어지고 있다. 또한, 곤달비의 종자는 대개 농가 자가 채종으로 생산되며, 채종재배에 대한 체계가 정립되어 있지 않다. 이에 본시험은 곤달비의 우량종자 생산을 위한 종자결실률 향상 재배조건과 채종적기를 구명하고자 하였다. 전북 남원시 허브산채시험장에서 2018년 10월에 2년생 곤달비 종묘를 포장에 정식하여 시험을 실시하였다. 적정 채종 재배조건을 구명하기 위해 2019년 노지, 하우스, 55% 차광막을 설치한 노지포장에서 곤달비의 개화시기, 개화율, 생육특성, 결실률 등을 조사하였다. 더불어 채종적기를 설정하기 위해서 곤달비 개화 후 50일~100일 동안 7일 간격으로 채종하여 결실률, 채종량, 종자 발아율을 조사하였다. 곤달비의 개화는 하우스재배, 노지재배의 경우 7월 하순, 차광재배는 8월 초순 개화가 시작되었으며, 개화 최성기도 하우스재배와 노지재배가 차광재배와 비교해 15일 정도 일렀다. 하지만 개화 종료 시기는 노지재배가 가장 빨랐으며 하우스재배가 가장 늦었다. 개화율은 하우스재배, 차광재배, 노지재배 순으로 높았다. 개화기 생육특성는 차광재배일 때 초장과 화경장이 가장 컸으며, 화서수와 자방수는 하우스재배가 타 재배방법에 비해 다소 많았다. 곤달비 재배방법에 따른 결실률은 차광재배가 70.1%, 노지재배가 21.9%, 하우스재배가 15.8%이었으며, 채종량은 차광재배의 경우 10a당 39.6kg, 노지재배 4.9kg, 하우스재배 4.6kg이었다. 백립중과 종자길이, 종자너비 또한 차광재배가 타 재배방법에 비해 양호하였다. 채종시기에 따른 결실률은 채종시기가 늦어질수록 높은 값을 가졌으나, 화경당 채종량은 개화 후 70일에 85일 사이에 가장 많았다. 발아율은 노지재배의 경우 개화 후 70일 이후부터 90% 이상으로 높은 발아율을 보였고, 차광재배는 개화 후 65일부터 95% 이상의 발아율을 나타냈으나 하우스재배의 경우에는 개화 후 80일 이후부터 85% 이상으로 발아율이 양호하였다. 따라서 곤달비의 우량종자를 생산하기 위해서는 55% 차광막을 설치한 노지에서 재배하여 개화 후 65일 이후부터 종자가 비산하기 전까지 채종해야 할 것으로 여겨진다.