• Title/Summary/Keyword: Atmospheric Effect

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Reddening Effect in the Solar Corona

  • Park, Y. D.;Kim, I. S.;N. L. Kroussanova;Y. J. Moon;E. A. Cho
    • Bulletin of the Korean Space Science Society
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    • 1999.09a
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    • pp.28-28
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    • 1999
  • No Abstract, See Full Text

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Studies on the Enzymes in Rice Bran (1) Change of Fat and Acid Value during preservatiou (米糠의 酵素化學的硏究 (第一報) (貯藏中의 脂肪과 酸價의 變化))

  • Lee, Sang-Tai
    • Journal of the Korean Chemical Society
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    • v.4 no.1
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    • pp.83-84
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    • 1957
  • I have studied on the Enzymes of rice bran during preservation heating at various periods at constant temperatures and under atmospheric pressure. I found following facts through experiments. 1. It increases A. V. ratio of rice bran oil at above 120$^{\circ}C$., but it does not effect on its fat by heating. 2. It increases A. V. ratio of rice bran oil rapidly at below 90$^{\circ}C$., while it does not effect on its fat during preservation.

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Simulation of effect of spray angle on the mixing effect in spray dryer absorber (분무건조 반응기에서 노즐 분사 각도에 따른 혼합효과의 전산 모사)

  • 송호철;김동주;함승주;박진원
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2002.04a
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    • pp.305-306
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    • 2002
  • 우리나라 폐기물 발생량은 1991년도까지는 연평균 8%의 증가를 보였으나 1992년 이후부터는 조금씩 감소하는 추세를 나타냈다. 폐기물 발생량의 감소요인은 배출원에서의 원천적인 감량화 노력과 함께 종량제 신시에 따른 쓰레기 분리수거 및 재활용율 제고 등에 따른 것이며, 특히 음식물 쓰레기 및 연탄재발생량의 감소가 크게 나타났다. 그러나 산업활동의 증가로 사업장 폐기물과 건축폐기물은 급증하는 추세를 보이고 있다. (중략)

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WRF Sensitivity Experiments on the Formation of the Convergent Cloud Band in Relation to the Orographic Effect of the Korean Peninsula (한반도 지형이 대상수렴운의 생성에 미치는 영향에 관한 WRF 민감도 실험)

  • Kim, Yu-Jin;Lee, Jae Gyoo
    • Atmosphere
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    • v.25 no.1
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    • pp.51-66
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    • 2015
  • This study was conducted to perform various sensitivity experiments using WRF (Weather Research and Forecasting) model in order to determine the effects of terrains of the Korean Peninsula and the land-sea thermal contrast on the formation and development of the convergent cloud band for the cases of 1 February 2012. The sensitivity experiments consist of the following five ones: CNTL experiment (control experiment), and TMBT experiment, BDMT experiment and ALL experiment that set the terrain altitude of Taeback Mountains and Northern mountain complex as zero, respectively, and the altitude of the above-mentioned two mountains as zero, and LANDSEA experiment that set to change the Korean Peninsula into sea in order to find out the land-sea thermal contrast effect. These experiment results showed that a cold air current stemming from the Siberian high pressure met the group of northern mountains with high topography altitude and was separated into two air currents. These two separated air currents met each other again on the Middle and Northern East Sea, downstream of the group of northern mountains and converged finally, creating the convergent cloud band. And these experiments suggested that the convergent cloud band located on the Middle and Northern East Sea, and the cloud band lying on the southern East sea to the coastal waters of the Japanese Island facing the East Sea, were generated and developed by different dynamical mechanisms. Also it was found that the topography of Taeback Mountains created a warm air advection region due to temperature rise by adiabatic compression near the coastal waters of Yeongdong Region, downstream of the mountains. In conclusion, these experiment results clearly showed that the most essential factor having an effect on the generation and development of the convergent cloud band was the topography effect of the northern mountain complex, and that the land-sea thermal contrast effect was insignificant.

Effect of Surface Ozone on Vegetation in Korea - Preliminary Study on Early Foliage of Robinia pseudo-acacia - (한국의 지면 오존이 식생에 미치는 영향에 관한 연구 - 아까시나무 조기낙엽 현상과 관련성 검토 예비 연구 -)

  • Cho, Seog-Yeon
    • Journal of Korean Society for Atmospheric Environment
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    • v.23 no.1
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    • pp.29-38
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    • 2007
  • Recently, the tropospheric ozone has gained a global attention for its adverse effect on vegetation as well as its contribution to the global warming. Although a number of studies have been carried out for the urban ozone, the effect of ozone on vegetation is still largely unknown in Korea. The present work aimed at performing the first evaluation of forest damage by ozone using the national air monitoring data from the year 2000 to the year 2005. Moreover, it also explored the relevance of adverse effect of ozone to the recent events on leaf chlorosis of black locust, Robinia pseudo-acacia, leading to early foliage widely observed in Korea since 2001. In the nineties, forest damages caused by ozone such as leaf chlorosis occurred in Europe and North America and led to invoke comprehensive field and laboratory studies. As a result, AOT40, implying the accumulated dose over a threshold 40 ppb, was developed to assess the forest damage by ozone. 19 air monitoring stations were selected across Korea to calculate AOT40 from the year 2000 to the year 2005. The calculated AOT40 generally increased during April and May and reached the maximum after May. The increase of AOT40 diminished substantially from the mid-June as the rainy season started. The calculated AOT40 in the nine rural sites from the year 2002 to th ε year 2005 ranged from 6.8 to 29.4 ppm-hr. And all the AOT40 at th ε year 2005 exceeded the critical value of 10 ppm-hr for forest damage. Morevoer the calculated AOT40 of Korea appeared higher than the AOT40 of Europe in the year 2004/2005 and comparable to the AOT40 of China in the year 2000. Despite the high levels of the calculated AOT40 since the year 2001 and the consistency of time of seasons between high AOT40 values and occurrence of chlorosis of black locust, further studies are required to conclude that the chlorosis of black locust occurred from the year 2001 to the year 2005 were resulted from a damage by ozone.