• Journal of Korean Society of Water and Wastewater
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• v.27 no.5
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• pp.591-601
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• 2013

In modern society, we are living indoor at 80 - 90 % or more of the day, therefore most people are exposed to unconscious indoor air pollutants by various causes. When mother and infant, whose level of immunity are weak, are exposed to polluted indoor air, respiratory diseases and atopy can occur by the growth of bacteria. Therefore, appropriate indoor air quality management is important especially at nursery, elementary school and postpartum clinic etc. In this study, we compared the characteristics of the indoor air qualities of primary school facilities and infant facilities. In this study, seasonal effects were investigated. Also the effects of individual activity area were studied for indoor air quality. During summer season(May-August), the air qualities of each 16 elementary school and nursery school were investigated. During winter season(October-december), the air qualities of each 10 elementary school and nursery school were investigated. As a result, during winter season in 10 of 16 nursery school, $CO_2$ concentration exceeded regulation level of 1000 ppm. This resulted from the operation of heating system and poor ventilation. Also the air quality of all parameters during winter season were worse than during summer, maybe due to poor ventilation. Except HCHO, the concentrations of other parameters were higher in nursery school. This seems to result from relatively low individual activity area of nursery school than elementary school. From this research, more strong regulation for ventilation and installation of air purifier should be implemented.

• Journal of Biosystems Engineering
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• v.31 no.3 s.116
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• pp.175-181
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• 2006

Nursery pig building is imperative to provide environmental conditions favorable to maintenance of piglet health and the efficiency of growth rate. To meet the ultimate goal, it is necessary to apply proper ventilation design and construction to a confinement livestock building. This study was conducted to investigate the performance of a modified ventilation system in terms of devised slot-inlet (modification I) and exhaust fan (modification II) to improve air change rate in a confined nursery pig building, with dimension of 5.9 m(W) ${\times}$ 12.6 m(L) ${\times}$ 2.2 m(H) in an Darby Genetic Station. The experiment was carried out in August, especially when the outdoor peak temperature were above $30^{\circ}C$ and the measured indoor environmental factors were temperature, air velocity, humidity and ammonia concentration which have been known to affect the piglet health and growth. There was no difference in indoor temperature between the original and modified ventilation systems, however the air velocity and ammonia concentration in confined nursery pig building with modified ventilation system were, in most cases, better performance than original ventilation system. Therefore, it was concluded that the slot-inlet system that kept indoor environmental factors pertinent and had an economic advantage, should be considered as a ventilation system for decreasing sensible heat from piglet in confined nursery pig building during extreme summer season.

• The Journal of Natural Sciences
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• v.10 no.1
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• pp.73-80
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• 1998

This experiment was carried out to investigate the effect of runner development based on production period and to investigate the yield in different cropping type to nursery plant age. In runner development experiment, heating + lighting + $GA_3$ + cluster removal treatment increased the number of runners by 13.1 times higher in spring season than control(heating only) in overwintering mother-plant. Treatment of 20ppm $GA_3$ was the most effective for runner production in autumn. In nursery plant age experiment, 60 days old nursery plants produced more flower cluster than 40 days old ones. This result indicated that the yield potential was so low that overwintering runners would be adaptable for spring or summer cultivation.

• Journal of Environmental Science International
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• v.16 no.8
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• pp.897-906
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• 2007

Effect of seawater temperature (temperature) on the production of anchovy, Engraulis japonica and laver, Porphyra tenera Kjellman, were investigated in the eastern part of South Sea of Korea (ESS). Bimonthly temperature data (Feb., Apr., Jun., Aug., Oct., Dec.) from 1980 to 2002 were collected from Korean Oceanographic Data Center (KODC) and monthly anchovy catch and laver production from 1980 to 2002 were used from published sources by the Ministry of Maritime Affairs & Fisheries, Korea. Effects of temperature on the two organisms were examined in four cases. In case of lower anchovy catch and higher laver production (1993), temperature during main spawning season of anchovy was about $0.2-0.6^{\circ}C$ lower than normal condition, and temperature during seed collecting season of laver in Namhaedo, Kojedo went down below $22.0^{\circ}C$. In case of higher anchovy catch and higher laver production (1995), optimum temperature for catch was formed in main fishing ground, temperature for seed collection was lower than $22.0^{\circ}C$, In case of lower anchovy catch and lower laver production (1996), temperature for spawning and catch was about $0.6-1.6^{\circ}C$ lower than normal condition, and temperature during seed collection in nursery was about $0.5-1.0^{\circ}C$ higher than optimum temperature for seed collection. In case of higher anchovy catch and lower laver production (1998), temperature during main fishing and spawning season was about $1.0-1.8^{\circ}C$ higher than normal condition, and temperature during laver seed collection in nursery was $1.5^{\circ}C$ higher than optimum temperature for seed collection.

• Research in Plant Disease
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• v.21 no.4
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• pp.273-279
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• 2015

Major diseases and insect pests in nursery season of strawberry were anthracnose, powdery mildew, Fusarium wilt, two-spotted spider mite, and aphids. Environmental-friendly and chemical application schedules can improve diseases and insect pests control with relatively fewer organic and chemical materials inputs compared with spray programs when it's occurred. Field experiments were performed in 2012 to 2013 according to calendar-based spray programs with environmental-friendly spray calendar (EFSC) and conventional chemical spray calendar (CSC) for controlling diseases and insect pests of strawberry plants cv, Seolhyang during the two nursery seasons. EFSC did reduce the incidence of diseases and insect pests as compared to the non-treated control. Incidence of anthracnose and powdery mildew by EFSC and CSC was similar in 2012 and 2013 seasons. In addition, occurrence of two-spotted spider mite in EFSC in 2013 was similar to those of CSC and was shown highly in early and mid-June both 2012 and 2013 seasons. Occurrence of aphid in EFSC was shown highly in early and mid-June both 2012 and 2013 seasons. These results suggest that EFSC program may be effective for controlling strawberry diseases and insect pests by using environmental-friendly organic materials.

• Korean Journal of Agricultural and Forest Meteorology
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• v.13 no.1
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• pp.1-9
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• 2011

This study was conducted to investigate the influence of different polyethylene film (P.E. film) for mulching on the changes in soil temperature and the production of good feathered apple nursery trees. M.9 rootstocks with stem diameter of 9.1~11.0 mm were planted in plots covered with different P.E. film (i.e., transparent P.E. film, black P.E. film, and bare soil as control). Three weeks after planting, the rootstocks were veneer grafted with 'Sinano Sweet' apple cultivar. In the middle of June, BA was sprayed to nursery for inducing feathering during the growing season. The soil temperature of the control was higher than air temperature by about $0.7^{\circ}C$ from mid April to early October, and that of P.E. film mulching was about $1{\sim}5^{\circ}C$ higher than that of the control. The soil temperature under transparent P.E. film was about $2{\sim}3^{\circ}C$ higher than that under black P.E. film. The diurnal range of soil temperature under the black P. E. film was lowest among all treatments. The P.E. film mulching induced better tree growth and feathering than bare soil. Percentage of good feathering apple nursery of black P.E. film was highest among all treatments because the soil temperature unuder black P.E. film in the early growing season was higher than that of the control and the number of days when the maximum soil temperature was over $35^{\circ}C$ in the summer was lower than that under the transparent P.E. film.

• Journal of Environmental Science International
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• v.23 no.12
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• pp.2083-2087
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• 2014

Between May and September 2014, a total of 226 serotine bats (Eptesicus serotinus) were captured and subsequently released at a site 50 km distant from the site of capture, in order to determine the homing ability of the bats and changes in the homing rate according to the season. The bats were captured from a nursery colony at a bridge in An-dong (Gyeongbuk, Korea), and then released at a similar site in Yeong-Ju (Gyeongbuk, Korea). We found that 115 of the 226 bats released (51%) returned to the capture site. However, there was a difference in the homing ability of the serotine bats depending on the season and reproductive status. We found that the homing rate was the highest in June during late pregnancy and the lowest in August after the lactation period.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.3
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• pp.337-342
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• 2016

Sea cucumbers have been an important part of human diets throughout history; demand is increasing every year, making the species a target for coastal resource development. New harvesting technologies have been developed in response to demand, including nursery production and insemination aquaculture, but such methods produce relatively few individuals and productivity per unit area is very small. For example, captures are prohibited during July and August due to the breeding season, and sea cucumbers aestivate during the hot season and hibernate during the cold season, all factors that limit natural-environment production in Korea. Problems with slow growth of sea cucumbers have been encountered in previous rearing experiments. To assess the importance of feeding ecology on sea cucumber growth, we conducted pond-bottom and lantern-net culture experiments. Results showed that sea cucumbers in bottom cultures grew from 3.06 to 102.59 g, but those in lantern cultures only grew from 25.60 to 28.03 g.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.6
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• pp.751-755
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• 2010

To understand the function of nursery grounds, the seasonal variation of ichthyoplankton was investigated in the East Sea, off Dokdo, from September 2009 to May 2010. The dominant species was Engraulis japonicus (92.7%), which occurred in May and September. The next abundant species was Maurolicus japonicus (5.7%), found in all four seasons. Several rare warm-water species were found in September and November, when the species diversity was higher than in the other two seasons. Several fish species used Dokdo as a nursery ground for a restricted season, while M. japonicus used it in all four seasons.

• Korean Journal of Medicinal Crop Science
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• v.20 no.5
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• pp.365-371
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• 2012

This study was carried out to know the characteristics of flowering and bearing fruit, the optimum period, regions and methods for seed harvesting, the optimum temperatures for seed storage and germination, and the optimum period for sowing at nursery bed and seedling transplanting of Valeriana fauriei Briquet. The flowering and bearing fruit of Valeriana fauriei was developed from the before-year root. Optimum period for seed harvest of Valeriana fauriei was from late July to middle August, and optimum areas were the high elevated areas over 500 m above the sea level as Jinbu-myeon, Pyeongchang-gun, Gangwon-do. Using of net-bag for seed harvesting was the effective method to gather the full ripe seed, and bagging of net-bag was necessary from the season of middle May that was the flowering middle-stage. Germination rates don't show the difference among the different temperatures of storage as approximately 41% at $-20^{\circ}C$, $2^{\circ}C$ or $20^{\circ}C$ of seed storage temperatures. The optimum temperature range was in $15{\sim}30^{\circ}C$ for seed germination at nursery bed. The optimum period for seed sowing at nursery bed was the late February, and the optimum period for seedling transplanting was the middle April.