• Journal of Animal Environmental Science
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• v.18 no.sup
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• pp.21-28
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• 2012

Since the temperature during summer is higher than the temperature which is suitable for milking cows, high temperature stress have severely affected dairy farmers due to decreased milk production. This study was carried out to investigate the effect of rainwater sprinkling system for reducing heat stress in milking cows during intense heat time. Treatment conditions were divided into 2 types ; No rainwater sprinkling (T1) and Rainwater sprinkling (T2). Temperature in the milking cow shed, feed intake, milk yield, respiration rate and rectal temperature were measured to investigate the effect of hot environment on the physiological, productive responses in milkig cows. The results obtained are summarized as follows : The daily milk yields were 24.5 and 27.4 kg per head in T1 and T2 during experimental period. The respiration rate was significantly higher in T1 than those of T2. The rectal temperature in T1 ($40.6^{\circ}C$) was higher than those of T2 ($39.8^{\circ}C$). It was suggested that rainwater sprinkling system installed in the dairy cow shed was effective means to reduce heat stress of milking cow.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1999.11a
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• pp.55-58
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• 1999

1. 스프링클러에 의해 하우스내를 관수한 경우, 하우스내 온도는 스프링클러 작동과 동시에 급격히 하강한 후 시간이 흐름에 따라 완만한 하향구배를 나타내었다. 2. 천 측창을 개방한 상태에서 스프링클러에 의한 냉각효과를 측정한 결과, 실내기준온도는 외기온 보다 약 2.8$^{\circ}C$ 낮은 온도를 나타내었다. 3. 본 실험결과 스프링클러 관수에 의한 냉각효과는 탁월한 것으로 조사되었으며, 관수시간대를 비교적 실온이 상승하는 주간시간대로 설정한다면, 그 효과를 극대화 할 수 있을 것으로 사료된다. 이 경우, 관수시의 수량 및 관수 지속시간 등에 대해서는 재배작물의 습해 등을 고려하여 이에 대한 면밀한 검토가 이루어져야 할 것으로 판단된다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.6
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• pp.487-490
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• 2004

Methods for culturing bean sprouts could be divided into two main groups of overspraying and underwatering according to water supplying. The study was done to measure the effect of water supplying method on growth of mungbean sprouts and temperatures inside their culture boxes. The morphological characters, fresh and dry weights were measured on the 6th day after culturing, but temperatures of the boxes were recorded daily by dataloggers. Lateral roots was not formed in the under-watering method (UM) while partially done in the over-spraying method (OM). OM had longer hypocotyl but UM had longer root compared to the other. Two water supplying methods, however, had nearly similar total length adding hypocotyl and root lengths, diameters of middle and upper parts of hypocotyl. OM showed more total fresh weight than UM mainly resulting from increment of hypocotyl fresh weight. The fresh weight increment in OM was caused by relatively higher temperature of culture box compared to UM.

• Korean Journal of Plant Resources
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• v.19 no.2
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• pp.344-347
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• 2006

Watering methods for soybean sprouts could be mainly divided into two groups of overspraying and underwatering. The study was carried out to determine the effect of water supplying method on growth, morphological characteristics, colour and cutting resistance of soybean (cv. Junjery) sprouts and culture temperatures. The morphological characters, fresh and dry weights were measured on the 6th day after their culture, but daily mean temperatures inside the plastic culture boxes were measured by data-loggers. Lateral roots were more formed in the underwatering method (UM) than in the overspraying method (OM). Although their total lengths of both methods were nearly same, OM had longer hypocotyl but UM did longer root than the other. Middle and upper parts of hypocotyl were more thickened in UM than in OM. UM showed more hypocotyl fresh and dry weights than OM. There was, however, no significant difference between the two methods in cotyledon, root, total fresh and dry weights although the culture temperature was higher in OM than in UM.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.1
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• pp.41-47
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• 2018

Soybean sprouts have good digestibility, high isoflavone content compared with soybean seeds, and large amounts of aspartic acid, which is effective in eliminating hangovers. However, the region between the cotyledon and hypocotyl in soybean sprouts appears purple, the product value of soybean sprouts reduces. To date, the scientific correlation among factors such as growth temperature, spray water temperature, and cultivation periods for soybean varieties related to purple color expression between the cotyledon and hypocotyl of soybean sprouts are unknown. The purpose of this study was to identify the factors regulating the expression of purple color between the cotyledon and hypocotyl of soybean sprouts. Of 15 Korean soybean varieties with purple color in the hypocotyls and flowers, 9 varieties, including Sowonkong, Wonhwang, Sinhwa, Eunhakong, Pungsannamulkong, Paldonamulkong, Kwangankong, Shingang, and Jangki showed purple color between the cotyledon and hypocotyl of sprouts. However, the remaining six cultivars, including Dachae, Myeongjunamulkong, Sobaeknamulkong, Sojinnamulkong, Anpyeong, and Jonam, did not show purple color. The proportion of soybean sprouts with purple hypocotyls was the lowest at $26^{\circ}C$ and there was no significant difference at the other three cultivation temperature conditions ($17^{\circ}C$, $20^{\circ}C$, and $23^{\circ}C$). Similar to the results of the cultivation temperature experiment at five different spray water temperatures ($10^{\circ}C$, $17^{\circ}C$, $20^{\circ}C$, $23^{\circ}C$, and $26^{\circ}C$), the proportion of soybean sprouts with purple hypocotyls was the highest at the lowest spray water temperature ($10^{\circ}C$), and lowest at the highest temperature. Additionally, there was no purple color expression in soybean sprout hypocotyls on the $3^{rd}$ day after soybean sprouting. However, the highest expression level was observed on the $4^{th}$ day. Then, on the $5^{th}$ day, the proportion of soybean sprouts with purple hypocotyls reduced significantly, compared with that on the $4^{th}$ day. The results showed that interaction among these factors under cultivation conditions was remarkably effective for the expression of purple color in hypocotyls under the dark condition. These results suggested that cultivation temperature and spray water temperature for purple color expression in soybean sprout hypocotyls are the most important factors in the sprout cultivation environment.

• Journal of Bio-Environment Control
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• v.10 no.1
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• pp.15-22
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• 2001

A soil temperature was known as extremely important factor in terms of measuring the values of the growth and yield of vegetable in the greenhouse. A low temperature water irrigation was had much trouble in its growth. This study was performed to analyze the effect of the heating water irrigation on the soil temperature and the growth of a cucumber within a greenhouse environment. Soil temperature was 5-7$^{\circ}C$ below to 10cm in depth and 2-3$^{\circ}C$ to 20cm when the irrigation water temperature was 13$^{\circ}C$ (non-warme water irrigation). Soil temperature was similar to irrigation water temperature at 5cm in depth and was 1.5-2$^{\circ}C$ below at 10cm when the irrigation water temperatures were 2$0^{\circ}C$, $25^{\circ}C$. The early growth rates of heating water irrigation were 109-110% in plant height, 107-108% in leaf number, 103% in node number compared with those of unheated water irrigation for 30 days after planting it. The rates of total yield were 115% in 2$0^{\circ}C$ water irrigation plots and 121% in $25^{\circ}C$ water irrigation plots while those of unheated water irrigation plots were.

• Plant Journal
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• v.10 no.1
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• pp.47-53
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• 2014

The national capacity of electricity of Korea was 81,737 MW and the peak demand was renewed by the record of 71,230 MW in 2012 which has been increasing since the first lighting ceremony had taken place in the Royal Palace(Kyung-Bok Goong) in 1887. Aa the counteract on the rapid increasing of the demand, Korean government is constructing and operating the high capacity nuclear and thermal power plants, however, the operating reserve on weekdays is small while those of weekends are more than 40% of capacity, so they are providing the pumped-storage power plants with the surplus electricity during weekends and operating the power plants which cost higher production price and located in the capital area with WSS (Weekly Start and Stop) mode including the Seoul Thermal Power Plant. Since the Seoul Thermal Power Plant is spending huge amount of expenses for more than 30 times of the WSS annually due to the high production cost even though it is in Seoul, the core of the demand, I chose the power plant unit #5 which was on the grid in 1969 for the case to confirm reducing 23% of the warm start-up time by applying the "Start-up time management program", and that reducing 35% of the water temperature increasing time by accelerate the increasing rate of the inlet temperature of the water circulating pump.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.2
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• pp.195-200
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• 1988

This experiment was carried out to evaluate the flooding injury and yield compensating ability by uppernode tillers formed during the recovery periods. Rice plants grown in experimental field transplanted on 1st, June were completely flooded for 3 days by the artificial flooding device in each different growth stage such as middle tillering stage (20 days after transplanting), young panicle formation stage, meiotic stage and heading stage. And the farmer's rice fields which had various transplanting dates were completely flooded for 3 days by typhoon 'Thelma' from 16th to 18th, July, 1987. Percent of dead leaves and yield reduction of rice in experimental field flooded at the different growth stages were resulted that the earlier growth stages were the lower damage because of the low temperature in the earlier growth stage, but it showed opposite tendency in farmer's rice field flooded in high temperature season by typhoon 'Thelma'. Rice yield compensating ability attained to 66% of check plot yield was greatly depend on uppernode panicles induced after damage of original young panicles. Uppernode panicle produced 236 kg per 10a in polished rice by securing 690$^{\circ}C$ of accumulated mean temperature and 210 hours of sunshine during the ripening periods when headed up to 15th of September.

• Asian Journal of Turfgrass Science
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• v.23 no.2
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• pp.229-240
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• 2009

The high temperature and water content in soil profile probably affect the physiological disorder especially on cool-season turfgrasses in warm and humid weather of Korean summer. The purpose of this research was to analyze the effect of soil temperature and water content on the growth and stress response of creeping bentgrass(Agrostis palustris Huds.) under a humid and warm temperature. USGA(United State of Golf Association) green profile in laboratory test, Daily temperature changes were tested under a dried sand, 70% water content of field capacity, and saturated condition at $34^{\circ}C$ of the USGA green in lab. In this test, the dried sand reached to $80^{\circ}C$, however, the surface temperature decrease of $10^{\circ}C$ on the saturated condition. In the thermal properties test in field, thermal conductivity, thermal diffusivity, and soil temperature were increased followed by irrigation practise. In the water-deficient condition, the highest soil temperature was reached temporally right after irrigation, however, the excessive soil water content higher than field water holding capacity showed the highest soil temperature after a while. This result indicated that a heat damage to root system was caused from the thermal conductivity of a high surface soil temperature. The excessive irrigation when a high turf surface temperature should occur a negative result on tufgrass growth, moreover, it would be fatal to root growth of creeping bentgrass, especially when associated with a poor draining system on USGA sand green. Overall, this study shows that high soil temperature with water-excessive condition negatively affects on cool-season grass during the summer season, suggesting that excessive irrigation, over 70% field capacity of soil condition, does not help to reduce soil temperature for summer season in Korea. In the study that cool-season grass were treated with different water content of soil, The soil had higher temperature and more water holding capacity when treatment rate of soil conditioner was increased. The best growth at the normal water condition and the worst state of growth at thee water-excessive condition were observed.

• Journal of Bio-Environment Control
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• v.27 no.2
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• pp.103-110
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• 2018

This study was conducted to investigate the optimum irrigation method for propagation of cutting strawberry ($Fragaria{\times}ananassa$ Duch. cv. Maehyang) plantlet in summer season. The cutting strawberry plantlets were planted in 24-cell tray ($60{\times}34{\times}10cm$) filled with commercial mixed medium (Tosilee) and placed in semi closed-type small plastic tunnel. Each semi closed-type small plastic tunnel was treated as follows; control (non-treatment), over head irrigation (twice a day), capillary mats irrigation (twice a day), or fog irrigation (30 minutes turn on and 10 minutes off from 8:00 to 18:00). The strawberry plantlets were rooted during 8 days in the semi closed-type small plastic tunnel, and then plastic film was removed. Growth parameters, such as plant height, root length, number of primary roots, petiole length, leaf length, leaf width, crown diameter, SPAD, leaf area, fresh and dry weights of the shoot and root, were measured at 61 days after cutting. Relative humidity in tunnel was high in the order by fog irrigation, over head irrigation, capillary mats, and the control as 72.5, 56.3, 45.8, and 29% on average, respectively. However, the air temperature was similar in all treatments. On the 4 and 8 days, the rooting rate of strawberry plantlet was significantly higher in the over head irrigation and fog irrigation treatments. Plant height, petiole length, crown diameter, and leaf area were highest in the over head irrigation and fog irrigation treatments. In addition, fresh and dry weights of shoot were greater in over head irrigation and fog irrigation treatments than the others. Dry weight of root was differed significantly heaviest in the fog irrigation treatment. However, root length, no. of primary roots, SPAD value, and fresh weight of root were not significantly different in all treatments. These results indicated that growth and rooting for propagation of cutting strawberry plantlet 'Maehyang' were best achievement in the over head irrigation and fog irrigation treatments.