• The Korean Journal of Malacology
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• v.6 no.1
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• pp.1-10
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• 1990

The occurrence of the larvae, the size of the spats daily attached to the collectors, the difference of the spat size with temperature, and the darly growth of a mussel, Mytilus edulis, were investigated at the off Songpo, Chinhae Bay, the southern part of Korea during the period from March 1 to August 30 in 1986. The water timperature and specific gravity ranged from 7.0 $^{\circ}C$ to 27.4$^{\circ}C$ (mean 17,24$\pm$5.9$0^{\circ}C$), and from 1.0126 to 1.0126(mean, 1.0242$\pm$0.0023), respectively. D-shaped larvae had two peak occurrences in March 8, April 19, Umbo-shaped larvad three peaks in March 8, April 21 and June 17, and full grown larvae two peaks in May 13 and June 23, respectively. Therefore, it is assumed that the mussel had two mass spawning time in early March and mid April and two mass settling time in mid May and alte June. The maximum size of the planktonic mussel larvae ranged from 375-400${\mu}{\textrm}{m}$ and most larvae sizing below 300${\mu}{\textrm}{m}$ long settled in adquate substrate. Spats just after settlement had the range from 26.5 to 547.3${\mu}{\textrm}{m}$ with the minimum of 225.0 ${\mu}{\textrm}{m}$ in mean shell length. The spats settled in summer season, when the water temperature raised above $25^{\circ}C$, were smaller than those settled in spring season in mean shell length. The early growth of the mussel spat had been assumed considerably fast.

• Journal of Bio-Environment Control
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• v.33 no.2
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• pp.79-87
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• 2024

This study confirmed the effects of seed shape, temperature, and light treatment on the germination of eight species of medicinal crops to produce high-value crops in vertical farms. Eight species of medicinal seeds were selected, and the seed shape, seed length, seed width, seed length/width ratio, and one hundred seed weight were measured. The seed moisture content was confirmed. Eight species of medicinal seeds were sown, and the germination rate, germination energy, mean daily germination, and mean germination time were investigated according to temperature (15, 20, 25, 25/15℃) and light treatment. Each of the eight medicinal seeds showed different seed shapes. The moisture content of the seeds showed a moisture content rate of over 20% in the five medicinal seeds. Medicinal seeds that showed a germination rate of over 50% were Angelica gigas Nakai, Codonopsis lanceolata (Siebold & Zucc.) Benth. & Hook.f. ex Trautv., and Achyranthes bidentata Blume var. japonica Miq. seeds. A. gigas seed showed a germination rate of 67.34 ± 4.38% under 25/15℃ light conditions, and C. lanceolata seed showed a germination rate of over 50% under both temperature and light treatment conditions, especially the highest germination rate of 82.67 ± 1.46% under 15℃ dark conditions. Peucedanum japonicum Thunb. seed showed a germination rate of 52.34 ± 1.77% under dark conditions at 20℃, and the highest germination rate was 51.67 ± 3.79% under dark conditions at 15℃. The maximum germination energy was 74.00 ± 4.94% in C. lanceolata seed. The maximum mean daily germination was 14.94 ± 0.15 days in P. japonicum seed. Astragalus penduliflorus Lam. var. dahuricus (DC.) X.Y.Zhu seed showed the highest mean germination time of 34.19 ± 4.71. Through this study, it was determined that A. gigas, C. lanceolata, and A. penduliflours seeds would be suitable for production in vertical farms based on the characteristics of each medicinal seed through analysis of seed germination characteristics.

• The Korean Journal of Ecology
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• v.23 no.4
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• pp.293-298
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• 2000

To study the effect of global warming on the growth of plants and plant populations throughout their life cycle under a field-like condition, we constructed a Temperature Gradient Chamber (TGC) in Tsukuba, Japan. The chamber had slender shape : 30 m long. 3 m wide, and 2.5 m high. That satisfactory performance was confirmed by a test throughout all seasons in 1998: the projected global warming condition in the near future was simulated. That is, independent of a great daily or seasonal change in ambient meteorological conditions, air temperatures at the air outlet were warmed 5$^{\circ}C$ higher than those at the ambient (the annual mean was 14.3$^{\circ}C$) with precision of ${\pm}$0.2$^{\circ}C$ (the annual means were 19.2$^{\circ}C$) with a rising rate of approximately 1$^{\circ}C$ every 5 m. This chamber will enable us to study the effects of global warming on growth of plants and plant populations because their abilities to control air temperature are excellent. TGC is expected that it would be utilized for studying the effect of global warming on plant growth under natural weather conditions.

• Journal of Korean Society for Atmospheric Environment
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• v.18 no.E3
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• pp.129-142
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• 2002

This paper provides a long-term perspective for ozone concentrations at 20 national air quality monitoring sites in Seoul from 1989 to 1998, which were managed by the Korean Ministry of Environment. Ozone episodes occurred more frequently in the east areas (Bangi, Guui, Seongsu, and Ssangmun) than in the west area (Guro and Oryu). When an ozone episode happened, hourly ozone concentrations over 80 ppb continued for an average of 4.0 hours at all sites. Annual variations in daily mean and maximum oBone concentrations showed broadly consistent upward trends at Ssangmun and Gwanaksan. Monthly mean ozone concentrations were the highest from May to June and the 99$^{th}$ and 95$^{th}$ percentile levels appeared higher during June, July, and August. The diurnal patterns of hourly mean ozone levels in urban areas showed typical photochemical formation and destruction, while the flat diurnal shape before 1996 at Gwanaksan indicated few significant photochemical reactions due to a lack of precursors of ozone. The occurrence of ozone over 80 ppb was ascribed to meteorological conditions such as high temperature, strong solar radiation, low relative humidity, and low wind speed with winds most frequently in a westerly direction.

• Journal of the Korean earth science society
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• v.32 no.7
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• pp.761-769
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• 2011

Daily minimum temperature and freezing data of the Seoul weather station ($37^{\circ}$34'N, $126^{\circ}$57'E, Songwol-dong Jongno-gu Seoul, hereinafter Songwol) and freezing data of the Han River station ($37^{\circ}$30'N, $126^{\circ}$57'E, hereinafter Han River) were used to study the long-term variation of the freezing climate for Seoul, Korea, for the period of 100 years from 1907 to 2006. 'Freezing' of Songwol is defined that the water in outdoor fields is frozen, and 'freezing' of the Han River located 6 km away from Songwol is defined as the region 100 meters upstream of the second and fourth piers in the south end of the Han River Bridge is fully frozen. The mean first freezing date for Songwol was October 28, and one for Han River was December 28; these showed a late tendency, with the rate of 0.78 days $decade^{-1}$ and 3.47 days $decade^{-1}$, respectively. The mean annual freezing days was 159.06 days for Songwol and 50.33 days for Han River; each showed a $decade^{-1}$shorter tendency, with rates of 2.01 days $decade^{-1}$ and 5.24 days $decade^{-1}$, respectively. All the seven no-freezing years (1960, 1971, 1972, 1978, 1988, 1991, and 2006) for Han River came after 1950. The mean daily minimum temperatures of the first freezing dates for Songwol and Han River were $0.55^{\circ}C$ and $-12.22^{\circ}C$. The first freezing occurred after 6.43 days for Songwol and after 8.94 days for Han River with daily minimum temperature below $0^{\circ}C$. The annual minimum temperatures of Songwol and Han River exhibited positive correlations with the first freezing date and negative correlations with freezing days. The result shows that the freezing climate change is relevant to temperature change and is a part of overall climate change. By conducting additional studies with various methods and wider region, we will be able to monitor the freezing climate.

• Journal of Climate Change Research
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• v.5 no.4
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• pp.285-289
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• 2014

The extension of growing season (GS) across the Northern Hemisphere have been linked to increasing temperature, related with global warming. Therefore, in this study, The start, end, and length of GS in Suwon, Korea from 1971 to 2013 based on observed daily mean air temperature are examined using three indices. The GS starts on average after $98.598.5{\pm}1.42$ Julian days and ends after $318.7{\pm}1.08$ Julian days. The average length of GS is $220.2{\pm}2.09$ Julian days. The length of GS in Suwon from 1971 to 2013 has been extended by 6.8 days/decade with an earlier onset of the GS (-4.1 days/decade) and later end of the GS (2.7 days/decade). This change may be due to an advanced start of the GS in spring rather than later end of the GS. In further study, it is necessary to select an index carefully to find the most suitable one for Korea.

• Ecology and Resilient Infrastructure
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• v.3 no.1
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• pp.46-53
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• 2016

This study was conducted to analyze the effect of the different land covers of an urban park (Hyowon park) in downtown Suwon on the urban thermal variations during a hot summer. The effect of the air temperature reduction in the urban park was 4.4%-4.5% for the downtown residence (Maetan-dong). This value was about 0.8% lower than that of the outskirts residence (Sanggwanggyo-dong). The daily mean temperature, daily maximum temperature, summer day and heat wave frequency were measured under the different land covers (cement-block, grass, pine-grass, shading area and mixed forest) showed these values generally decreased under natural land cover types. Daily minimum temperature and tropical night frequency didn't seem to correlate with the land cover types. Means of thermal comfort indices (wet bulb globe temperature, heat index and discomfort index) in the shading area, mixed forest and the pine-grass types were lower than those of cement block and grass types. However the levels of those indices were equal to 'very high' or 'caution' levels in the afternoon (13:00-15:00). In the morning (06:00-08:00), thermal comfort indices of the urban park didn't correlate with land cover types. Therefore, to reduce heat stress and to improve the thermal comfort in urban parks, an increase in the area of natural land cover such as grass, forest and open spaces is required.

• Journal of Animal Environmental Science
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• v.11 no.2
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• pp.103-110
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• 2005

The study was carried out to develop the real time measuring technique of ammonia and carbon dioxide concentration emitted from growing-finishing pig house in winter and estimate ammonia emission rate emitted from the pig house. As the study was carried out, environmental management technique for the pig house and odor abatement skill could be properly developed to reduce the residence's annoyance. The room temperature of the growing-finishing pig house was $10^{\circ}C$ higher than outdoor air temperature in spite of additional heating, because of heat emitted from body temperature of the pigs. The daily variation pattern of room temperature in the pig house shows the similar tendency with outdoor air temperature. The daily mean ventilation rate per head was $16\;m^3/h$ and ranged from $12\;m^3/h$ to $22.4\;m^3/h$. The difference of day and night for ventilation rate was about 2 times. The ammonia emission rate was $208{\pm}28\;mg/h{\cdot}pig$ per daily basics calculated with ventilation rate and ammonia concentration.

• Journal of the Korean association of regional geographers
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• v.12 no.4
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• pp.461-474
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• 2006

This paper aims to analyze regional characteristics of unusual temperature events on summer and winter. The major data used in this study are the daily mean temperature of summer (June-August) and winter (December-February) and wind field on 850 hPa height. Regions of unusual temperature are divided into five regions by the monthly frequency of unusual temperature occurrence. The divided regions are following as: the middle east coastal region (I) where the summer unusual high temperature occurrence frequency is highest; the Gyunggi west coastal and northern middle inland region (II) where winter unusual low temperature occurrence frequency is highest and winter unusual high temperature occurrence frequency is low; the western middle and south region (III) where unusual temperature occurrence ratio is not concentrated on specific season; the forest and southern east region (IV) where unusual high temperature is low; and the south coastal and Jeju island region (V) where winter unusual high temperature is highest.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.4
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• pp.397-406
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• 2009

This study was carried out to investigate the microclimate (photosynthetically active radiation and temperature) response to different shading materials(shade plate, and polyethylene net) on Korean ginseng(Panax ginseng C.A. Meyer) bed. Photosynthetically active radiation(PAR) under polyethylene net was approximately 24 ~ 30% higher than that under shade plate on sunny day. Also, PAR was remarkably decreased from the front to the rear rows of ginseng beds. Temperature under polyethylene net was higher than that of shade plate. Internal temperature under polyethylene net was 1.9 ~ 3.1% higher than that under shade plate at the different rows of ginseng bed. Mean of total daily temperature under polyethylene net was higher at the rear rows than at the front rows, while that under shade plate was higher at the front rows than at the rear row of ginseng bed. Mean of total daily temperature on sunny days(April 15 and May 17) was 7.3% lower under shade plate than above outside but, polyethylene net was 0.7% high, while that on cloudy days(April 11 and May 15) was 1.6% higher under polyethylene net than above outside, but shade plate was 0.7% low. Also, overall mean of total daily temperature under polyethylene net was 7.0, 7.8, and 8.8 % on sunny day(April 15 and May 17), and 1.7, 1.6, and 3.5% on cloudy day(April 11 and May 15) higher than that under shade plate, respectively. The SPAD values of 6 years old ginseng at two point(front, center) in bed under shade plate showed the highest value, and the lowest under polyethylene net. The SPAD of 6 years old ginseng at rear in bed was not statistically significant under two shading materials.