• Journal of The Korean Society of Grassland and Forage Science
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• v.4 no.3
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• pp.180-186
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• 1984

From June, 1980 to October, 1982, this study was carried out to find an optimal grazing system on the timothy and orchardgrass-dominated pasture. Five different systems consisted of set stocking, modified set stocking, rotational grazing, 'wye college' system and zero grazing have been applied. The results obtained were as follow: 1. Herbage DM yield per ha with 'wye college' system, set stocking, modified set stocking, rotational grazing and zero grazing were 6936.7 kg,6794.3 kg, 6686.9 kg 6675.7 kg and 5083.4 kg respectively. Among treatments were not different in DM yield. 2. In herbage utilization, zero grazing was the highest than other. Zero Grazing, Rotational grazing, 'Wye college' system, Modified set stocking and set stocking was 89.3%, 70.8%, 64.4% and 46.1% respectively. 3. Daily intake per head with 'wye college' system was the highest than others and zero grazing was the lowest than others. 4. Daily gain with 'wye college' system, rotational grazing, modified set stocking, set stocking and zero grazing were 0.60kg, 0.55kg, 0.50kg, 0.43kg and 0.42 respectively. Among treatment, there was no significance. 5. Total weight gain per ha with 'wye college' system, rotational grazing, modified set stocking, zero grazing and set stocking were 339.5kg, 299.1kg, 253.3kg, 226.6kg and 222.2kg respectively. 6. Grazing time among treatments was not significant. 'Wye college' system spent the shortest time, 367.3 minutes and set stocking consumed the longest time, 422.1 minutes. 7. Daily grazing time by seasonal change with June, July, August, September and October was 304.9 min., 359.4 min., 437.9 min., 483.3 min. and 395.8 min., respectively. According to passing the season, grazing time was lengthened. 8. Grazing time for Korean native cow, native cow charolais and native cow holstein were not significant. Native sow charolais consumed the longest time, 457.0 min., whereas Korean native cow consumed the shortest time, 422.4 min..

• Journal of Biosystems Engineering
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• v.3 no.1
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• pp.47-63
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• 1978

This study was conducted to obtain a basic information necessary to assess present rice milling technology in Korea The profiles for milling plants was analyzed by survey work.For the private custom-work mills, which process about 80 percent of domestic rice consumption ,their actual milling test for the identical samples as used for filed mills was conducted. Two rice varieties Japonica and Tongil-type were associated with the experiments. The results are summarized as follows: 1. Analyses for private custom-work mills showed their general aspects as; about 91 percent of the mills belonged to an individual owner ship ; more than 93 percent of the mills was established earlier than 1950 ; about 80 percent of the mills was powered with electric motor; mills having less than two employees were about 75 percent; about 45 percent of the mills provided for warehouse in storing customers cereal grains. 2. The polishers installed in 1,255mills within the surveyed area (7 counties) have been supplied by 44 different domestic manufacturers ;in but about 60 percent of which was supplied by 6major manufacturers. The polishers could be classified into two categories in terms of principles of their polishing actions ;jet-pearler and friction types. About 51 percent of the mills was equipped with the former which has been recognized as giving greater milling recovery than the friction types. 3. Reason for owners of private mills to supplement new machines was due mainly to pgrading their mills to meet the requirements that established by the Government. However, about 60 percent of the mill owners intended to replace with new pearler by their own needs to meet with new high yielding varieties. 4. Processing systems of each previate rice mills surveyed could be classified into three categories, depending upon whether the systems posessed such components as precleaner and paddy separator or not. Only 36.7 percent of mills was installed with both precleanr ad paddy seperrator, 5.0 percent of mills did have neither percleaner nor paddy seperator, and rest of them equipped only one of the two. Hence,it is needed for about 63% of rice miils to be supplemented with these basic facilities to meet with the requirements for the standaized system. 5. Actual milling capacity measured at each field rice mills was shown a wide variation, having range from about 190 to 1,210 kg/hr. The percentages of mills classified according to daily milling capacity based on this hourly capacity were 24.3% for the capacity less than 3 M/T a day; 20.0% for 3-4 M/T; 15.6% for 4-5 M/T; 6.7% for 5-6 M/T; 22.3% for 6-7 M/T; and 11.0% for more than 7 M/T a day. 6. Actual amount of rice processed was about 310 M/T a year in average. About 42% of total milled rice was processed during October to Decembear, which formed a peak demand period for rice mills. The amount of rice milled during January to May was relatively small, but it had still a large amount compared to that during June to September. 7. Utilization rate of milling facility, i. e., percentage of the actual amount of milled rice to the capacity of rice mills, was about 18% on the year round average, about 41% in the peak demand season, and about 10% during June to September. Average number of operating days for mills surveyed was about 250 days a year, and about 21 days a month. 8. Moisture contents of paddy at the time of field mill tests were ranged 14.5% to 19.5% for both Japonica and Tong-i] varieties, majority of paddy grains having moisture level much higher than 1530. To aviod potential reduction of milling recovery while milling and deterioration of milled rice while storage due to these high grain mJisture contents, it may be very important for farmers holding rice to dry by an artificial drying method. 9. Milling recovery of JapJnica varieties in rice mills was 75.0% in average and it was widely ranged from 69.0% to 78.0 % according to mills. Potential increase in milJing recovery of Japonica variety with improvement of mill facilities was estimated to about 1.9%. On the other hand, milling recovery of Tong-il varieties in the field mill tests was 69.8% in average and it ranged from 62% to 77 %, which is much wider than that of Japonica varieties. It is noticed that the average milling recovery of Tong-il variety of 69.8% was much less than that of the Japonica-type. It was estimated th3.t up to about 5.0% of milling recovery for Tong-il variety could be improved by improving the present lo'.ver graded milling technology. 10. Head rice recoveries, as a factor of representing the quality of commercial goods, of Japonica and Tong-il varieties were 65.9% and 53.8% in average, and they were widely ranged from 52% to 73% and from 44% to 65% , respectively. It was assessed that head rice recovery of Japonica varieties can be improved up 3.3% and that of Tong-il varieties by 7.0% by improving mill components and systems.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.3
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• pp.223-231
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• 1999

This study was carried out to investigate the factors influencing water quality of the river (Mankyeong River) and groundwater in controlled horticulture region from 1994 to 1998. Water quality of Mankyeong River was monitored at 13 sites along main stream for 6 months from April to September from 1994 to 1997. Monthly average concentrations of $NH_4-N$, $SO{_4}^{2-}$ and $Cl^-$ were highest in April, while that of $NO_3-N$ was highest in August. Monthly average concentrations of COD was highest in September Concentrations of $NH_4-N$ and $SO{_4}^{2-}$ in many sites of Mankyeong River exceeded the water quality criteria of agricultural water for irrigation. Water quality of Mankyeong River was not suitable for the irrigation source excepted the sites such as Hari, Gosan and Soyang stream. The floodgates of Mokcheon, Yocheon, Jeonju and Samcheon streams were rapidly polluted by the municipal sewage, otherwise the Iksan stream was rapidly polluted by the sewage of swine. The sum of inorganic ion concentrations in Mankyeong River was highest at floodgate of Yocheon due to the sewages municipal and industrial. The order of the major anions and canons concentration in Mankyeong River- stream were $SO{_4}^{2-}$ > $Cl^-$ > $NO{_3}^-$ > $PO{_4}^{3-}$ and $Na^+$ > $Ca^{2+}$ > $NH{_4}^+$ > $Mg^{2+}$ > $K^+$, respectively. The geoundwater quality at controlled horticulture region was surveyed 4 sites from 1994 to 1998. Concentrations of $NH_4-N$ and $NO_3-N$ were lower at the deeper groundwater. However there was no difference between the concentrations of $SO{_4}^{2-}$ and $Na^+$, and the groundwater depth below 15m. Contents of $NH_4-N$, $NO_3-N$, $PO{_4}^{3-}$, $SO{_4}^{2-}$, $Na^+$ and $Cl^-$ in groundwater were the highest at dry season. Nitrate-N level, exceeded $20mg\;l^{-1}$, the critical level for agricultural usage, at Yongjinmyeon Wanju and $PO{_4}^{3-}$ concentration were higher at Seogtandong Iksan than the other places.

• Journal of Animal Environmental Science
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• v.14 no.3
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• pp.149-158
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• 2008

The purpose of this study was to determine the effect of milking system type on milking center effluent production through the four seasons. Four different types of milking systems (Bucket, Pipeline, Tandem and Herringbone) were estimated, in duplicate, through the different seasons. The following conclusions can be drawn from this study. 1. The quantity of wastewater produced from Tandem and Herringbone milking systems were significantly larger than Bucket milking system (p<0.05). 2. The main wastewater production was from the washing of milking apparatus. Tandem and Herringbone milking systems produced 398.8 and $407.7{\ell}$/day of wastewater, respectively, for apparatus washing. These values were significantly higher than the other milking systems during the summer (p<0.05). 3. The average wastewater production from the various milking systems was $15.4{\ell}$/head/day. The quantity of wastewater production during summer ($16.4{\ell}$/head/day) season was higher than of the other seasons. 4. The highest level of $BOD_5$ ($906.4mg/\ell$) was produced from the washing of the parlor floor and the lowest level of $BOD_5$ ($212.4mg/\ell$) was produced from the washing of the udders of the cows. 5. The pH of dairy wastewater was in the range of $7.3{\sim}8.2$ and the average levels of $BOD_5$, COD, SS, T-N, and T-P were 731.2, 479.0, 751.6, 79.1, $14.7mg/\ell$, respectively. Following conclusions can be drawn from this experiment. The quantities of wastewater production from Bucket, Pipeline, Tandem and Herringbone milking system were 143.9, 487.9, 914.0, and $856.7{\ell}$, respectively. The average wastewater produced from the milking systems was $15.4{\ell}$/head per day. In order to effectively manage on the wastewater from milking systems, dairy farms need to consider the milking system type and farm size when determining the optimum wastewater treatment system.

• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.3
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• pp.211-216
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• 2009

Approximately 43 million tons of livestock manure (LM) are produced each year on Korean farms. LM can be utilized as a valuable resource and/or it can contaminate water by runoff and leaching through the soil, when LM has been thoughtlessly applied to the land and directly discharged into the water. This experiment was carried out to investigate the effect of no-till system and LM application on dry matter (DM) yield of silage corn and $NO_3$-N concentration in leaching water of lysimeter installed in the experimental field. The treatments were replicated three times in split plot design. Main plots consisted of tillage systems, such as conventional tillage (CT) and no-tillage (NT). Sub plots consisted of the type of LM, such as chemical fertilizer (CF), composted cattle manure (CCM) and composted swine manure (CSM). The control plots were fertilized as commercial chemical fertilizer. DM yields of corn increased significantly in order to CF > CCM > CSM (p<0.05). DM yield of corn in CT increased as comparing with that of corn in NT. Plant height, ear height and stem diameter also increased in order to CF > CCM > CSM. In addition, the root weight in CT was increased as comparing with that of corn in NT. However, there was no interaction effects of between type of LM and tillage system. $NO_3$-N concentration in leaching water of LM application was less than 10 ppm, but $NO_3$-N concentration in CF exceeded 10 ppm which is safety level of drinking water during summer time (rainfall season).

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.16 no.2
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• pp.81-96
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• 2011

Sediment oxygen demand(SOD) and denitrification rates were measured in four major estuaries(Suncheon Bay, Seomjin river estuary, Goseong stream estuary and Masan Bay) in south coast of Korean peninsula from March of 2009 to May 2010 to estimate organic matter cleaning capacity. SOD was estimated from the temporal dissolved oxygen concentration change and isotopic pairing technique was employed to measure denitrification. Sediment oxygen demand(SOD) was ranged from -5.1 to 24.6 mmole $O_2m^{-2}d^{-1}$ and denitrification rate was ranged from 0.0 to 3.9 mmole $N_2m^{-2}d^{-1}$in the study area. SOD was the highest in Masan Bay(-2.2 to 19.2, average = 10.2 mmole $O_2m^{-2}d^{-1}$) and Suncheon, Goseong, Tae-an and Seomjin followed. Denitrification was also the highest in Masn Bay(0.0 to 3.9, average = 1.0 mmole $N_2m^{-2}d^{-1}$) and Goseong, Seomjin, Suncheon and Taean followed. The effect of benthic photosynthesis by microphytobenthos on denitrification was evident in some season of Tae-an, Seomjin, and Masn Bay. The increased oxygen level produced by photosynthesis stimulated nitrification without severe adverse effect on denitrification and, as a result, coupled nitrification and denitrification was enhanced in these areas. A difference of seasonal patterns of denitrification at each site depended on relative importance of denitrification on different nitrate source($D_w$: nitrate from water column and $D_n$: nitrated produced during nitrification). Denitrification was maximum during spring in Goseong, Suncheon and Masan Bay. On the contrary, denitrification was the highest during summer in Tae-an and Seomjin estuary.

• Research in Plant Disease
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• v.17 no.3
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• pp.272-279
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• 2011

Fusarium species are worldwide causal agents of Fusarium head blight (FHB) in cereals such as barley and wheat. Their toxigenic potential is a health risk for both humans and animals. To survey the natural occurrence of FHB and mycotoxins produced by Fusarium, total 126 barley or wheat grains grown in 2009-2010 season in Korea were collected. The incidence of FHB was 30.7% in silage barley, 26.9% in wheat, 20.7% in naked barley, 19.4% in malting barley, 16.4% in unhulled barley. Overall FHB incidence of barley and wheat in 2010 was 23.0% and 10% higher than that of 2009. The incidences and level of deoxynivalenol (DON), nivalenol (NIV), and zearalenone (ZEA) were 34%, 0.89 mg/kg, 84.9%, 1.86 mg/kg, and 10.3%, 0.06 mg/kg respectively. The both levels and incidences of NIV were found to be highest in barley, whereas the level of DON was found to be highest in wheat. Incidences of DON and NIV and the level of NIV in the samples from southern regions of Korea were higher than those from central region, whereas the level of DON from central region was higher than that from southern regions. This is the first paper demonstrating regional difference in natural occurrence of DON and NIV in wheat and barley.

• Research in Plant Disease
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• v.17 no.3
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• pp.342-350
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• 2011

Throughout the years 2008 to 2010, we analyzed approximately two thousand oriental melon samples collected from Seongju, using electron microscopy and testing by RT-PCR using primers specific for eight cucurbit-infecting viruses. Data from RT-PCR indicated that Cucumber green mottle mosaic virus (CGMMV), Watermelon mosaic virus 2 (WMV2) and Zucchini yellow mosaic virus (ZYMV) were present and the other viruses were not detected. Among them, CGMMV and WMV2 were the most prevalent pathogens. CGMMV was thought to infect oriental melon from the early growing season, and reached nearly 100% in the later of growing period. Otherwise, WMV2 emerged from June, several months later compared to CGMMV. CGMMV was detected from all aerial parts of the oriental melon including seeds, but not from the roots of the grafted pumpkin rootstock. Seed of two out of five commercial varieties were shown to be CGMMV positive. Nine varieties of pumpkins used as rootstocks were not infected with CGMMV. When the seedlings of grafted oriental melon were transplanted into pots mixed with the oriental melon debris infected with CGMMV, they were not infected by CGMMV. Cutting of pruning shear and the contact of tendrils contributed 48% and 30% to the transmission of the virus, respectively.

• Pediatric Infection and Vaccine
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• v.14 no.2
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• pp.155-161
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• 2007

Purpose : We evaluated the epidemiologic characteristics of rotavirus gastroenteritis in Daejeon, Korea from January 2001 through December 2005. Methods : We retrospectively analyzed 540 medical records of children with gastroenteritis, who had been hospitalized at The Catholic University of Korea, Daejeon St. Mary's Hospital and were tested positive by rotavirus stool examinations (latex agglutination or immunechromatography). Results : The mean age was $21.8{\pm}15.3$ months (ranged from 2 months to 9 years of age) and the distribution of children were 144 cases (26.7%) in <1 year of age, 228 (42.2%) in 1 year of age, and 93 (17.2%) in 2 years of age, and the 505 children (93.5%) were less than 4 years of age. The male-to-female ratio was 1.4:1. The mean annual number of cases was 108, with a relative even occurrence in each year. Although the patients with rotaviral gastroenteritis occurred through the year, a higher rate of occurrence was seen in spring (March to May, 40.8%) and winter season (December to February, 37.9%), without significant differences in each year. Conclusion : In Daejeon, Korea, rotaviral gastroenteritis have occurred in children less than 4 years of age, with slight annual variations and similar seasonal occurrence in the recent years. The data indicate that the recent trend in peak rotavirus activity is different from that observed decades ago in Korea.

• Journal of Preventive Medicine and Public Health
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• v.22 no.2 s.26
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• pp.290-301
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• 1989

This is preliminary report on anthrax epidemic occurred in an island with about 100 residents. Since 1982 there had been sudden deaths among all kinds of domestic animals including cattle, dogs, ducks, chicken and goat but only a few among cats in an isolated island about three hours distance away by ferry boat from Mokpo city. From 1986 through 1988 nine human deaths and four patients occurred, which made the government intervene for investigation on June 25 1988. The epidemiological investigation consisted of interview survey and medical examination, medical record analysis, laboratory work to isolate the pathogens under the direction of hypothesis derived from the study and further confirmation of the pathogens by international institute. The summarized results are as followings: 1. According to the interview survey there were many deaths among domestic animals usually in cold and dry season such as January through March and September through November; 36 heads of cattle leaving one head, more than 40 hogs(all), hundreds of chicken leaving few alive, goats that had taken home from mountain and two or three cats out of around 40 had sudden deaths from 1982 till 1985, when the residents stopped to purchase and take them into the island anymore. Also there were eleven persons who had experienced the similar syndrome complex to those of admitted and expired patients and four of them revealed typical chest X-ray findings; from one of these four patients(Rho) B. anthracis is isolated. 2. Medical record on patients who had been admitted, showed common characteristics of the disease course. On admission they had either gastrointestinal or upper respiratory infection symptoms which invariably progressed to septicemic nature with pulmonary interstitial infiltration and mediastinal widening/bulging, and then to deadly acute respiratory distress syndrome. At the end stage chest X-ray revealed multiple bullous emphysema. One of another characteristics was oral ulceration with bleeding occurred in about 50% of the patients. Laboratory test results in common were leukocytosis with left shift and abnormal liver and kidney functions, particularly at the later stage of the illness. 3. Epidemiological characteristics was striking in that both mortality and incidence rates were high: the mortality rate was 8.7% average, male being three times higher than females but there was no distictive clustering by age group. The incidence rate for both sexes was 28.2% and there was no sex difference although a tendency of higher incidence among older ages was noticed. The highest mortality and incidence were observed in Won village where the first death of animal occurred and with the highest frequency among three villages of the island. 4. Among twelve bacilli species isolated from various specimens, two strains, one from patient and the other from soil where the recently died cow is hurried, were confirmed as B. anthracis by Pasteur Institute and CDC of USA(strain from soil). CDC reported that the strain did not produce capsule in bicarbonate media but reacted with the bacteriophage and one of five sera taken from the patients. Mode of transmission as well as incubation period of the agent has not been established yet, which needs further investigation in relation to the antigenic structure of the variant when it is confirmed.