• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제37회 하계학술대회 초록집
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• pp.188-188
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• 2009

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제37회 하계학술대회 초록집
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• pp.189-189
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• 2009

• 아동학회지
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• 제22권4호
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• pp.331-341
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• 2001

This study is to investigate whether young Korean children have understanding for testing hypothesis. Questions explored are; First, do children have notions of testing hypothesis? Or, do they just produce an effect? Second, choosing between conflicting hypotheses, can children distinguish between experiments that would produce conclusive and inconclusive evidence? For this study, 15 first grade and 15 second grade children in elementary school located in Kyunggi area near Seoul participated. Data collection and analysis were based on interviews with children for two weeks. Children were presented two conflicted hypotheses to decide which one is correct through conclusive evidence and inconclusive evidence in the interview. The results showed that children(1st: 93.3%, 2nd: 81.3%) of each grade can distinguish between hypothesis and evidence to do testing hypothesis, and distinguish between conclusive and inconclusive evidence. In conclusion, most young children have understanding of testing hypothesis based on their familiar experiences, so it was possible for them to differentiate hypothesis from evidence in certain situations.

• 한국작물학회지
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• 제43권4호
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• pp.254-258
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• 1998

Distribution and occurrence of weedy rice in Kyonggi region were surveyed in 1996. Weedy rice was observed in 1368 fields (54.9%) of total 2490 fields. Almost two thirds of paddy fields in northern mountainous region were contaminated by weedy rice and more severe contamination, three forths of paddy fields, was observed in suburban regions. In those regions, occurrence of weedy rice was greater than those in north-eastern inland and south-western plain regions. The occurrence of weedy rice was higher in water seeding cultivation (66.7%) than other cultivation methods. The number of weedy rice per 10a was 756.7 plants in direct seeding on dry paddy and 379.4 plants in water seeding. The occurrence of weedy rice was higher in fields planted by farmer's seeds than that of paddy fields cultivated by certified seeds, and the longer the farmer's seeds being used, the more weedy rice occurred in paddy field.

• 한국유기농업학회지
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• 제19권spc호
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• pp.92-95
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• 2011

The initial investment of rice cultivation by mechanical technique was high. This was only due to the cost of planting machine. We analysed the overall cost (without machine cost) and benefits of the two methods, it manifested that the mechanical method is very much beneficial over traditional rice cultivation technique. We observed that the requirement of soil, irrigation water, number of seeds etc. decreased in mechanical cultivation technique while net income increase by 13.07% with 80% government subsidy. Furthermore, the initial rooting was quicker, growth and development of pot raised seedlings was better than the traditional technique. Hence, this technique can give better return to the farmers with the help of government subsidy.

• 한국유기농업학회지
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• 제19권spc호
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• pp.135-138
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• 2011

In traditional organic rice culture practices, control of weeds is a big problem. This study was conducted to increase the rice production. Results showed that Plant height, SPAD, root length and weight were higher in pot raised seedling than broadcasting method except number of panicles. High plant density caused reduction in plant height, number of culm and chlorophyll content of the rice. No lodging was observed in both methods. Thickness of third internode and culm length was more in pot raised seedlings at both sites. When organic material was used rice yield increased by 3.81%. Higher rice production (10%) was recorded in the fields planted with pot raised seedlings. From the above study it could be conclude that the pot raised seedlings perform better than the seedlings raised by broadcasting methods.

• 한국식품위생안전성학회지
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• 제28권2호
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• pp.158-167
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• 2013

This study was carried out to assess the safety of cereals and their products (20 species, 205 samples) distributed in Gyeonggi province by analyzing contamination levels such as exposure frequency of Aflatoxins and Deoxynivalenol (DON). Aflatoxins were detected in 16 (8%) samples in total with a range of 0.01~27.88 ${\mu}g/kg$, including 3 of 9 bake flour (33%), 2 of 6 dried corn (33%), 3 of 12 frying flour (25%) and 2 of 11 sorghum (18%). DON was found in 56 (27%) samples including 11 of 13 adlay (85%), 6 of 8 wheat (75%), 6 of 10 processed corn for popcorn (60%), 6 of 11 sorghum (55%) and 7 of 16 barley (44%) with a range of 2.2~754.4 ${\mu}g/kg$. In particular, both Aflatoxins and DON were detected in 8 samples (2 millet, 2 wheat, 1 sorghum, 1 adlay, 1 dried corn, 1 bake flour) simultaneously. As a result of this study, we found that an adult is exposed to Aflatoxins of $0.80({\times})10^{-3}{\mu}g/kg$ b.w./day and DON of 0.18 ${\mu}g/kg$ b.w./day. The quantity of exposure to DON amounted to 18.5 percentage level compared with PMTDI 1 ${\mu}g/kg$ b.w./day suggested on JECFA, therefore we can assess that the possibility of health risks by intake cereals distributed in Gyeonggi province is low. However the concentration of Aflatoxins in one dried corn was 27.88 ${\mu}g/kg$ which was over the maximum residue limits (MRL) suggested on internal and external level, the monitoring about mycotoxin should be conducted on continuously.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2000년도 춘계 학술대회지
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• pp.162-163
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• 2000

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2005년도 춘계 학술발표대회
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• pp.72-73
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• 2005

• 한국작물학회:학술대회논문집
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• 한국작물학회 2001년도 추계 학술대회지
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• pp.168-169
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• 2001