• Journal of The Korean Society of Agricultural Engineers
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• v.47 no.1
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• pp.79-91
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• 2005

Wetland systems are widely accepted natural water purification systems around the world in nonpoint sources pollution control. Constructed wetlands have become a popular technology for treating contaminated surface and wastewater. In this study, the field experiment to reduce nonpoint source pollution loadings from polluted stream waters using wetland system was performed from June 2002 to March 2004, including winter performance using four newly constructed wetlands. The Dangjin stream water flowing into Seokmun estuarine lake was pumped into wetlands, and inflow and hydraulic residence time of the system was $500m^{3}{\~}1500m^{3}/day\;and\;2{\~}5$ days respectively. After 3 years operation plant-coverage was about $80~90\%$ from zero at initial stage even with no plantation. Average water quality of the influent in growing season was BOD_{5}\;3.96mg/L$, TSS 22.98 mg/L, T-N 3.29 mg/L, T-P 0.30 mg/L. The average removal rate of four wetlands for $BOD_{5},\;TSS,\;T-N\;and\;T-P$ in growing season was $24\%$, $62\%$, $54\%$, and $51\%$, respectively. And average water quality of the influent in winter season was $BOD_{5}$ 4.92 mg/L, TSS 12.47 mg/L, T-N 5.54 mg/L, and T-P 0.32 mg/L, respectively. The average removal rate of four wetlands for them was $-21\%$. $23\%$, $33\%$, and $53\%$, respectively. The reason of higher BOD_{5} effluent concentration in winter season might be that low temperature restrained microorganism activity and a organic body from the withered plant and algae was flown out. Except the result of $BOD_{5}$, the effectiveness of water quality improvement in winter season was satisfactory for treating polluted stream waters, and $BOD_{5}$ variation was within the range of background concentration. Performance of the experimental system was compared with existing data base (NADB), and it was within the range of general system performance. Overall, the wetland system was found to be satisfactory for NPS control such as improvement of polluted stream water.

• Journal of Embryo Transfer
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• v.25 no.4
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• pp.287-290
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• 2010

On January 6, 2010, two months earlier than normal breeding season, a red fox vixen was implanted with synthetic GnRH analogue, Deslorelin. Blood was sampled every 2~3 days from the day of implant to identifying spermatozoa on stains of epithelial cells. Estradiol and progesterone were examined. Even though the vixen was in non-breeding season, she was mated by a male fox. Pregnancy was confirmed by canine pregnancy detection kit that detect relaxin released from placenta. Four healthy pups were born on March 9, 2010. This is the first report showing synthetic GnRH can activate ovarian function and lead to fertile estrus of red fox in non-breeding season.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.5
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• pp.578-584
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• 2006

This research analyzed the contents of ascorbic acid according to cultivating season, regions and cooking method. The ascorbic acid content was steadily increased from 40.08 mg per 100 g on the 5th days after blooming to 90 mg on the 30th day, an increase of 2.25-fold. The ascorbic acid content of the peppers was highest for (C) region at 100.9 mg per 100 g, followed by (B) region at 90 mg and (A), region at 23.35 mg. it increased by ascending downward from the stem. If examining species' and regional ascorbic acid change of marketing peppers, it was contained in flesh most and placenta, seed in order in four species. The ascorbic acid content of the peppers was affected by the cooking method and decreased greatly in the order of blank>microwave>$saut{\acute{e}}ing$> boiling> steaming.

• Journal of Acupuncture Research
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• v.17 no.4
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• pp.18-27
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• 2000

There is a acupuncture method which make a difference according to the four seasons, according to body region or depth in skin. We call it Acupuncture follow the four seasons(四時刺法). In several chapters of Huangdineijing(黃帝內經) introduced Acupuncture follow the four seasons. Acupuncture follow the four seasons has two kinds of acupuncture method that is to acupuncture at body region and to acupuncture at five Su points(五兪穴). To use five Su points(五兪穴) according to Yongchu(靈樞) disagree with Nanjing(難經). In Yongchu(靈樞), the five phases property disagree with five Su points(五兪穴), but in Nanjing(難經) the five phases property agree with five Su points(五兪穴). Even if we can acupuncture the same point, there will be the different effect according as what is the purpose of doing acupuncture, and when we do acupuncture. That is to say, we can use apucupuncture for the purpose of prevention in Yongchu(靈樞), and for the purpose of healing the disease in Nanjing(難經). Therefore, because we select the point on the base of meridian Kis origin which spring out, we have to acupuncture Chong point(井穴) in winter according to Yongchu(靈樞). Because we select the point on the base of meridian Kis origin which flowing, we have to acupuncture Chong point(井穴) in spring according to Nanjing(難經). And in the base of five phases' property, the purpose of selecting five Su points(五兪穴) is the prevention according to Yongchu(靈樞), and the healing according to Nanjing(難經). So even though we acupuncture the exactly same Chong point(井穴), we can expect the effect that acupuncture method supply Ki for liver in winter. and the effect that it extract pathogenic Ki(邪氣) from the liver in spring.

• Journal of Korean Society on Water Environment
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• v.28 no.3
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• pp.394-400
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• 2012

We drew the stage-discharge relations of Byeokgye Stream, located in Yangpyeong-gun, Gyeonggi-do, and analysed the correlation between items of water pollutants by measuring the flow rate and water pollutants thirty-four times from April 2010 to December 2010. The results showed that it tended to be low water season from April to June and from October and December, while tending to be water season from July to September. The average flow rate was $2.137\;m^3/sec:\;0.464\;m^3/sec$ in low water season and $13.970\;m^3/sec$ in high water season. The stage-discharge curve thereon was $Q=40.107{\times}(h-1.200)^{2.877}$. As to the correlations, the correlation between the water temperature and COD was 0.58, and the correlations of SS with BOD and COD were 0.46 and 0.40 respectively. The correlation between SS and T-P was 0.73, showing higher than other items.

• Journal of the Korean Institute of Landscape Architecture
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• v.25 no.2
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• pp.62-72
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• 1997

This study was conducted to find out the hydroseeding timing of several herbaceous plants for the slope revegetation works. Four native plants and five introduced grasses were used for this experiment and were seeded on the cut slopes by hands in April, May, June, September and October. To identify the best seeding timing, germination percentage, ground covering rate, number of tillers and plant heights were investigated. There were wide differences in germination and ground covering rates of native plants are lower than those of cool-season foreign grasses and they show different germination rates according to seeding timing. Among them, Arundinella hirta var. ciliata shows the most apparent germinatin pattern according to seeding timing. 2. Seeding timing : Native plants tend to germinate well in May and June and cool-season foreign grasses in May and September. But Native plants show extremely low germination rates in autumn, so it is necessary to adjust the seeding rates when seeding in autumn. When seeding in May, it will be possible to use native plants-seed-mixture without using introduced foreign grasses. In sum, the best seeding timing of cool-season foreign grasses are May and September, and warm-season foreign grass is May and June. The best seeding timing of native plants seem to be in May and June.

• Korean Journal of Veterinary Research
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• v.61 no.1
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• pp.7.1-7.7
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• 2021

The levels of aflatoxin (AFT) and ochratoxin (OCT) were assessed at different seasons in raw materials, different feed manufacture processing stages, and animal feeds in feed mills in Korea implementing the hazard analysis and critical control point (HACCP) system. Two hundred samples were collected in all four seasons from five feed mills implementing the HACCP system and examined for AFT and OCT contents. The AFT and OCT levels were analysed by using HPLC method to provide information on raw material and product stage. The AFT content of raw ingredients in the spring season was highest in corn gluten (3.84 ppb) and lowest in corn (1.82 ppb) The AFT content of corn was highest in the winter season (2.17 ppb). The content of OCT in wheat was highest in the winter season. The amounts of AFT and OCT at processing stages were higher than in the raw materials or feed. In particular, AFT content was higher in the transfer stage (3.88 ppb) than in the mixing (2.86 ppb) or filling stages (3.45 ppb) in the summer season. The means of AFT and OCT level in laying hen feed was 3.41 ppb and 1.14 ppb for broiler feed, respectively. The means of AFT and OCT level in and broiler feeds was 3.44 ppb and 1.17 ppb for broiler feed, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.2
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• pp.275-281
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• 2013

The objective of this study was to determine the effect of slaughter season on the fatty acid profile in four types of fat deposits in crossbred (Polish Holstein Friesian Black-and-White${\times}$Limousine) beef bulls. The percentage share of fatty acids was determined by gas chromatography and were divided into the following categories of fatty acids: saturated (SFAs), unsaturated (UFAs), monounsaturated (MUFAs), polyunsaturated (PUFAs), desirable hypocholesterolemic (DFAs) and undesirable hypercholesterolemic (OFAs), n-3 and n-6. Perinephric fat was characterized by the highest SFA concentrations (59.89%), and subcutaneous fat had the highest MUFA content (50.63%). Intramuscular fat was marked by a high percentage share of PUFAs and the highest PUFA/SFA ratio. The slaughter season had a significant effect on the levels of C18:3, C20:4 ($p{\leq}0.01$) and conjugated linoleic acid ($p{\leq}0.05$). There was an interaction between the slaughter season and fat type for the content of C20:4 ($p{\leq}0.01$) and C20:5 ($p{\leq}0.05$). The results of this study show that beef from cattle slaughtered in the summer season has a higher nutritional value and more health-promoting properties.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.1
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• pp.78-85
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• 1987

In order for Paldanghomil (winter rye) to be investigated if its grain yield is able to be produced after clipping just before winter season for forage utilization this experiment was carried out under the four sowing dates of four locations in Korea (Chunchon, Suwon, Hwasung and Chungju). In rye clipping plot earlier sowing showed taller plant height, more number of tillers/㎡ and higher forage yield before winter season, indicating the highest forage yield (1803 kg/10a) in Chunchon by sowing of September II. Forage yield of rye before winter season was mainly influenced by plant height and number of tillers/㎡, showing more effect of plant height. Rye plants were more or less affected on winter damages, late heading and short culm by clipping before winter season. Analysis of variance indicated that only number of spikes/㎡ among grain yield components showed the high significance according to the clipping method, and that there showed little variation for other yield components due to the sowing date and clipping method. There showed more grain yield in non-clipping rather than that of clipping plot, indicating the difference of 46kg/10a. This was resulted from short culm and severe winter damages caused by clipping before winter season. Of the grain yield components, number of spikes/㎡ was greatly influenced for grain yield by analysis of stepwise regression. Therefore, grain yield of rye was able to produce after forage utilization before winter season due to the appropriate crop and soil managements, by resulting from the little variation in grain yield between clipping or non-clipping plots and from the higher grain yield by the early sowing.

• Journal of Animal Reproduction and Biotechnology
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• v.37 no.4
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• pp.298-302
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• 2022

South Korea has a temperate climate with four distinct seasons. However, summers are extremely hot and humid, which negatively affects industrial animal production. Hanwoo are native cattle that have traditionally been raised in the natural environment of Korea. The present study investigated the effects of birth and lactation season on the birth and weaning weights of Hanwoo calves. Data were collected from 100 local breeding farms between 2016 and 2021. A total of 56,970 (males, 29,530; females, 27,440) Hanwoo calves were classified according to sex or birth and weaning season (March-May, spring; June-August, summer; September-November, fall; and December-February, winter). The birth weight of Hanwoo calves differed according to the birth season. As such, birth weight of the summer-born calves was the lowest. Additionally, the 90-day weaning weight was positively correlated with birth weight. Interestingly, however, the 90-day weaning weight was not related to the birth season but was related to the 2-month seasonal effect during the lactation period. Furthermore, the 90-day weaning weight was the lowest during the summer lactation period. In the beef cattle industry, daily weight gain is an important economic characteristic related to feed efficiency and growth. Our findings will contribute the management of Hanwoo cattle and analysis of changes in economic characteristics due to high temperatures.