• Korean Journal of Environmental Biology
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• v.23 no.3 s.59
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• pp.304-314
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• 2005

The occurrence of cyanobacterial bloom in Korean lakes of the summer is generalized. The characteristic of cyanobacterial community was explored. And the developmental stage of cyanobacterial bloom was divided into three phases, 'preparatory phase', 'bloom phase' and 'extinction phase' Cyanobacterial bloom started during the end of June at site 1, transition Bone of Lake Daecheong. The period of water bloom in normal year was about 60~70 days at site 4, lacustrine Bone, but it was unusually 11 days from July 19 in 1999. M. aerugilnosa first occurred in June, had a peak of standing crop curve from the end of August to the beginning of September in 1998 and 2002 and the end of July in 1999 and 2001. The standing crop of M. aeruginosa occupied $68.1\%$ of phytoplankton, $74.2\%$ of cyanobacteria and $88.8\%$ of genus Microcystis, Anabaena spp. first occurred in April, was above 10,000 cells $mL^{-1}$ from the end of August to about the middle of September in 1998. The effect of rainfalls on cyanobacterial bloom was different according to the phases. The rainfalls of preparatory phase assist the growth of cyanobacteria, but accelerate the decrease of cyanobacteria in extinction phase. In bloom phase, the heavy rainfalls reduce the development of the bloom, while the slight ones display only a little effects.

• Horticultural Science & Technology
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• v.29 no.3
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• pp.195-200
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• 2011

The growth, yield and quality of Sedum sarmentosum between soil and hydroponic cultivation were compared to produce high-quality shoots in summer season. The plants were collected from four places in Korea and cultivated in a plastic film house with 50% shading. A 1:1:1 mixtures of sand, upland soil and substrate (N-P-K: 330-220-400 $mg{\cdot}L^{-1}$) was used for soil cultivation, and a nutrient film technique (NFT) with Yamazaki-lettuce nutrient solution used for hydroponics. After 30 days of cultivation, plant height ranged from 18.4 to 21.8 cm and showed no significant difference between soil and hydroponic cultivation. Number of shoot, leaf length, leaf width, number of leaf, fresh weight, and dry weight significantly increased in hydroponics compared to those in soil cultivation. Fresh and dry weights in hydroponics were greater in 'Gunsan' and 'Wando' collections than those in other collections. Stem diameter and compression-force significantly increased in soil cultivation rather than hydroponics with significant differences among collections. However there were no significant differences in shoot bitterness and vitamin C content between cultivation methods or among the collections. Most mineral contents except Fe in hydroponics were higher than those in soil cultivation. K, Na, Zn contents in hydroponics were over 2 times higher than those in soil cultivation.

• Korean Journal of Medicinal Crop Science
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• v.4 no.4
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• pp.333-339
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• 1996

The root and stem bark of Eleutherococcus spp. is used for the treatment of paralysis, rheumatism, arthritis, diabetes, stamina failure, high blood pressure, etc. This study was con­ducted to identify botanical origins and to select standard variety of Eleutherococcus spp. with analyzing eleutheroside E content(%) of root bark and that of Eleutherococcus senticosus at different collected area, time, part and grown area. The content of eleutheroside E in the root bark was determined by HPLC, and it was 0.1925% in Eleutherococcus senticosus, 0.1103% in E. chiisanensis, 0.0348% in E. koreanum and 0.0236% in E. sieboldianum. In seasonal change of eleutheroside E content, it was higher in autumn product than summer product in Eleutherococcus senticosus. It also was higher in root bark than stem bark in different part. To investigate eleutheroside E content of root bark among different collected local area in E. sen­ticosus, it was high order to Mt. Deokyu, Hokkaido and Mt. Seolak as a 0.1625%. 0.0493% and 0.027 %, respectively. The growth of Eleutherococcus senticosus was good at grown Unbong (altitude 10m), but eleu­theroside E content was high at grown Nogodan (altitude 1, 450m).

• Journal of Bio-Environment Control
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• v.6 no.1
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• pp.48-54
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• 1997

Among the various vegetables eggplant and gourd family can stand against high temperature environmental condition, about 35$^{\circ}C$. However, most of greenhouse farmers are giving up crop cultivation during hot summer season due to extreme temperature, 4$0^{\circ}C$ or above, condition of greenhouse interior. To improve this inferior crop growth condition, for nozzle system was installed in the pet greenhouse and the effect of fog system was investigated in order to determine fog water amount and the required fog nozzle numbers according to house volumes. MEE fog nozzle was selected for this Investigation which can produce water particle size of 27${\mu}{\textrm}{m}$ with water amount of 100$m\ell$ at pumping pressure of 70kg/$\textrm{cm}^2$. House cooling test was conducted in the pet greenhouse with one minute fogging and one minute air ventilation without stopping. It maintained 32$^{\circ}C$ at the house interior when the atmosphere and the house temperature were 35 and 4$0^{\circ}C$, respectively. And, an experimental equation was developed through calculating the changes of relative humidity and temperature with psychrometric equation which revealed the moisture transfer pattern between the house air and fog system. It showed that the required water fogging amounts to reduce 1$0^{\circ}C$, 40 to 3$0^{\circ}C$, needs 80.7$\ell$ for 1-2W(8,350㎥) and 99.9$\ell$ for 3-2G-3S(10,330㎥) type greenhouse with particle size of 27${\mu}{\textrm}{m}$.

• Journal of The Korean Society of Grassland and Forage Science
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• v.36 no.2
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• pp.129-134
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• 2016

Odor in pig manure affects the distribution of the manure over grass and crop fields as fertilizer. The objective of this study was to investigate the effect of different types of microbes (Saccharomyces cerevisiae, Bacillus subtilis and Rodobacter capsulata) and incubation temperatures ($20^{\circ}C$ and $35^{\circ}C$) on the levels of odorous compounds in pig manure. Pig manure was incubated with 0.03% microbes (v/v) at temperatures of $20^{\circ}C$ or $35^{\circ}C$. At incubation temperature of $20^{\circ}C$, the addition of Rodobacter capsulata significantly (p<0.05) decreased the levels of indoles and volatile fatty acid (VFA). At incubation temperature of $35^{\circ}C$, the addition of any microbes of the three used in this study did not significantly (p>0.05) affect the levels of odorous compounds. When incubation temperature was increased from $20^{\circ}C$ to $35^{\circ}C$, levels of odorous compounds were significantly (p<0.05) increased. Taken together, these results suggest that Rodobacter capsulata could be utilized to reduce odor from pig manure in the spring and fall when the average temperature is around $20^{\circ}C$. However, alternative odor-reducing technology is needed to be developed to apply onto pig manure during the hot summer season ($35^{\circ}C$).

• FLOWER RESEARCH JOURNAL
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• v.16 no.1
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• pp.44-48
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• 2008

This experiment was conducted to examine the effect of injecting cool air from an abandoned mine during the summer time for the growth of Doritaenopsis. The air temperature of abandoned mine in Boryeong was $12{\sim}14^{\circ}C$. The day and night temperatures were set at $22^{\circ}C$ and $20^{\circ}C$, respectively, from June to August in the experimental plastic house. This temperature range was within the suitable range for floral induction in Doritaenopsis. Average outside temperature was $28.4{\sim}32.8^{\circ}C$. The 3% of the crop developed flower stalk in 20 days after the treatment initiation, 65% in 45 days, and 100% in 90 days. The flower stalk length was short (48.7cm) in 30 days and long (62.4cm) in 60 days of treatment. The flower stalk length became longer as time passed. Flower spike and number of florets per stalk displayed the same tendency. Number of nodes was 6~7 and was not affected by the period. The first blooming appeared on 15th of September at 45 days and blooming tended to appear late as the period is lengthened. When the cool air from an abandoned mine was injected, the crop formed flower stalk three months earlier and bloomed four months earlier than the untreated control.

• Korean Journal of Breeding Science
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• v.40 no.4
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• pp.447-451
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• 2008

'Goamibyeo', a mid-late maturing ecotype with high amylose content in kernels, was developed by the rice breeding team of National Yeongnam Agricultural Experiment Station(NYAES) in 2000 and released in 2001. This variety was derived from the three way cross of Milyang 95//Kimcheonaengmi/$2^*Ilpumbyeo$ (in 1992 summer) through the pedigree breeding method and designated as 'Milyang 168' in 1997. The heading date of 'Goamibyeo' was Aug. 18 in ordinary season with culm length of 85 cm. However, 'Goamibyeo' showed susceptible to bacterial leaf blight, stripe virus and leaf blast disease. The amylose content of 'Goamibyeo' in milled rice kernels is about 26.7% with translucent and clear in chalkness. Thus, 'Goamibyeo' is expected to be used as a source grain for rice noodle industries. The milled rice yield potential of 'Goamibyeo' is about 5.38 MT/ha in local adaptability test of three years and it would be adaptable to Yeongnam plain of Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.21 no.1
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• pp.43-51
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• 1976

Marine deposite soil was studied to evaluate morohological changes of paddy rice under subdrainage control. The content of organic and inorganic mate rial were low at high temperature in the mid-summer. This soil lacked air and accumulated more H$_2$ S. Thus rice root was rotted with high infection of virus and insect and yield was relatively low.

• Korean Journal of Agricultural Science
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• v.45 no.1
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• pp.43-49
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• 2018

The species of forage crops used in this study were Italian ryegrass (cv. Kowenery), sorghum (cv. SX17), proso millet (cv. domestic) and Japanese millet (cv. Jeju). The plant height of the summer crops was the highest at the dough stage. The dry matter yield of Italian ryegrass was 902.7 kg per 10 a. The dry matter yield of the winter crop and sorghum was 11,985 kg when harvested at the dough stage rather than at the first and second harvests. The proso and Japanese millet also had higher yields for dry matter during the dough stage rather than during heading and regeneration. The acid detergent fiber (ADF) content of Sorghum was lower than that of the first and second harvest; however, the proso and Japanese millet had a higher ADF content at the dough stage. The neutral detergent fiber (NDF) content was higher at the dough stage than at the first and second harvest, and the crude protein content was also lower at the dough stage than at the first and second harvest. The crude protein production for the dry matter yield was about 84 kg in Sorghum when harvested at the dough stage. Proso millet showed no difference for the crude protein production at the heading and dough stage while the Japanese millet had a higher crude protein production. There were no differences in the total digestible nutrients (TDN) content for the three crops according to the harvesting time. Therefore, if Sorghum and Proso and Japanese millet are to be combined with Italian ryegrass, it is better to harvest them at the dough stage.

• Journal of Bio-Environment Control
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• v.7 no.3
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• pp.237-245
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• 1998

Greenhouse crop production under critical summer climate In Korea has considerable difficulties because of high temperature and relative humidity. In this study, some water pipes were tested as a means of the dehumidification and increment of evaporative cooling efficiency. As a result of heat transfer characteristic analysis, overall heat transfer coefficient of copper pipe was larger than steel pipe, and estimated values were smaller than measured values. The condensed quantities of vapor were not significantly different between copper pipe and steel pipe, however dehumidifying effect by the water pipes was significantly large. It was estimated based on the results that the evaporative cooling system by the water pipe will be able to increase the evaporative cooling efficiency of about 48%, and decrease the temperature of about 1.3$^{\circ}C$.