• Title/Summary/Keyword: season changes

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Effedts soil moisture on Photosythess , Transpiration and Stomatal resistance in Sorghums I. On seasonal changes (토양수분이 수수류의 광합성 , 증산량 및 기공저항에 미치는 영향 I. 광합성과 증산량의 계절간 변화)

  • 한흥전;류종원
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.6 no.1
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    • pp.53-59
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    • 1986
  • The effects of soil moisture on seasonal changes of photosynthesis, transpiration and stomatal resistance were studied in sorghum (Pioneer 931) and sorghum - sudangrass hybird (Pioneer 988) at Suweon in 1985. Soil moisture was maintained with approximately 100, 80, 60 and 40% of field moisture capacity in large concrete pot (12m length $\times$ 1m width $\times$ 1m depth). 1. Photosynthesis and transpiration showed a sharp seasonal changes and reacted similarly to water stress and environmental factors, and were the highest in the middle of August, and were the lowest in the beginning of October. Sorghum - sudan hybird had better photosynthesis, transpiration and stomatal control than those of sorghum in hot summer season. 2. The rate of photosynthesis of 60 and 80% field moisture capacity was higher than that of 100 and 40% throughout growing season, but the effect of soil moisture on photosynthesis varied seasonally by climate factors. Optimum soil moisture was 60% in early summer and fall, and was 60 - 80% in hot summer season. 3. Drought and over-moisture affected physiological metabolism of plant, and so the dry matter yield of 40 and 100% field moisture capacity decreased by 70% compared with that of 60% field moisture capacity.

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Analysis of Changes in Power Generation of Each Power Generation Company by the Fine-Dust Seasonal Management System (미세먼지 계절관리제로 인한 발전사별 전력생산량 변화 분석)

  • Kim, Bu-Kwon;Won, Doo Hwan
    • Environmental and Resource Economics Review
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    • v.30 no.4
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    • pp.627-648
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    • 2021
  • The fine-dust season management system refers to the policy of implementing enhanced reduction measures in transportation, power, business and living sectors in winter, when fine dust levels are high. The fine dust season management system is a regulatory policy that causes social costs and transfers to various economic players. Equity is an important issue for the cost burden. Therefore, in this study, the cost of each power generator was analyzed using the coal power generation reduction amount of each power generator to verify that the cost of the power sector is evenly distributed. In particular, the effect of the fine dust season management system on coal power generation of power generators was analyzed by applying a synthetic control method that can identify the time-variable effect of the policy. It was confirmed that the fine dust season management system reduced volume of fuel and power generation in coal power plants, resulting in an increase in the cost of the power generation sector, even considering the effect of some power demand due to the COVID-19 crisis. However, it could be seen that these costs were not distributed equally among the generators, and that they were more costly to the specific generators.Social costs incurred by fine dust season management need to be improved so that stakeholders are equally burdened.

Relative contributions of weather systems to the changes of annual and extreme precipitation with global warming

  • Utsumi, Nobuyuki;Kim, Hyungjun;Kanae, Shinjiro;Oki, Taikan
    • Proceedings of the Korea Water Resources Association Conference
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    • 2015.05a
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    • pp.234-234
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    • 2015
  • The global patterns of annual and extreme precipitation are projected to be altered by climate change. There are various weather systems which bring precipitation (e.g. tropical cyclone, extratropical cyclone, etc.). It is possible in some regions that multiple weather systems affect the changes of precipitation. However, previous studies have assessed only the changes of precipitation associated with individual weather systems. The relative contributions of the weather systems to the changes of precipitation have not been quantified yet. Also, the changes of the relative importance of weather systems have not been assessed. This study present the quantitative estimates of 1) the relative contributions of weather systems (tropical cyclone (TC), extratropical cyclone (ExC), and "others") to the future changes of annual and extreme precipitation and 2) the changes of the proportions of precipitation associated with each weather system in annual and extreme precipitation based on CMIP5 generation GCM outputs. Weather systems are objectively detected from twelve GCM outputs and six models are selected for further analysis considering the reproducibility of weather systems. In general, the weather system which is dominant in terms of producing precipitation in the present climate contributes the most to the changes of annual and extreme precipitation in each region. However, there are exceptions for the tendency. In East Asia, "others", which ranks the second in the proportion of annual precipitation in present climate, has the largest contribution to the increase of annual precipitation. It was found that the increase of the "others" annual precipitation in East Asia is mainly explained by the changes of that in summer season (JJA), most of which can be regarded as the summer monsoon precipitation. In Southeast Asia, "others" precipitation, the second dominant system in the present climate, has the largest contribution to the changes of very heavy precipitation (>99.9 percentile daily precipitation of historical period). Notable changes of the proportions of precipitation associated with each weather system are found mainly in subtropics, which can be regarded as the "hotspot" of the precipitation regime shift.

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Influence of Vegetaton Type on the Intensity of Ammonia and Nitrogen Dioxide Liberation from Soil (토양으로부터 휘발되는 암모니아와 이산화질소의 소실에 대한 식피형의 영향에 대하여)

  • 김천민
    • Journal of Plant Biology
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    • v.14 no.3
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    • pp.43-46
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    • 1971
  • Losses of nitrogenin the gaseous form were determined with closed systems in the filed under different vegetation types. Ammonia volatilization was greatest from the pine stand, and least from the sod stand, and was greatly reduced in all three sites in the rainy season due to the low temperature. There were only insignificant differences in the nitrogen dioxide volatilization from the soil of the three vegetation types. Losses of ammonia and nitrogen dioxide at various soil depth also showed little variation. Evidently the microbial activity responsible for the $NO_2$ loss was relatively unaffected by the changes in temperature and soil moisture content during the investigation.

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The Study on the ${\ulcorner}$Sun Gi Il Il Bun Wi Sa Si(順氣一日分爲四時)${\lrcorner}$ of the ${\ulcorner}$Young Chu(靈樞)${\lrcorner}$ ("영추.순기일일분위사시(靈權.順氣一日分爲四時)"에 대한 연구(硏究))

  • Kim, Young-Ha;Ruk, Sang-Won
    • Journal of Korean Medical classics
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    • v.18 no.1 s.28
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    • pp.33-48
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    • 2005
  • The purpose of this study is that translates ${\ulcorner}$Sun Gi Il Il Bun Wi Sa Si${\lrcorner}$ in the ${\ulcorner}$Young Chu(靈樞)${\lrcorner}$ as a modern words because it is hard to understand which was written by classical words. We revised the original text with the 7 other classic books and classified annotations of the 6 annotated books according to the similar contents. We classified this volume by 3 chapters, and added Hangul suffixes to the original text. The Five types of changes(五變) in the second chapter is meaning to the mutual relationships among the Five viscera and Color, Time, Day, Note, Taste. The word order of contents in the second chapter must be unified follow the Color, Time, Day, Note, Tastes. The Five types of changes in the third chapter must be revise the Five types of diseases(五病) on the bases of the ${\ulcorner}$You Kyoung(類經)${\lrcorner}$.

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Changes on the Quality of Market Milk on the Storage Conditions (저장 조건에 따른 시유의 품질변화)

  • 이수원;황보식
    • Food Science of Animal Resources
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    • v.21 no.2
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    • pp.156-162
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    • 2001
  • The quality changes of UHT market milk product were investigated by the season and storage conditions. Throughout the year, standard plate counts(SPC) wasnt increased significantly during storage at 5$\pm$1 and 7$\pm$1$^{\circ}C$ for 10 days. And except for summer, SPC was lower than 20,000 cfu/ml after storage at 10$\pm$1$^{\circ}C$ or 10 days. But SPC was rapidly increased from 3 days at 15$\pm$1$^{\circ}C$, and there was gas forming by yeast growth after storage at 30$\pm$1$^{\circ}C$. Values of pH and titratable acidity of market milk products were 6.49 to 6.71 and 0.155 to 0.16%, respectively. pH and titratable acidity were a lot changes at the temperature over 15$\pm$1$^{\circ}C$, and milk products showed a curd at 30$\pm$1$^{\circ}C$. Carbohydrate of market milk product had little difference throughout the year, whereas fat, protein and total solids of market milk products in autumn showed a little higher value than that of other seasons. There were no changes of milk composition during storage periods, but carbohydrate was decreased a little after storage over 20$\pm$1$^{\circ}C$.

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Analysis for Air Temperature Trend and Elasticity of Air-water Temperature according to Climate Changes in Nakdong River Basin (기후변화에 따른 낙동강 유역의 기온 경향성 및 수온과의 탄성도 분석)

  • Shon, Tae Seok;Lim, Yong Gyun;Baek, Meung Ki;Shin, Hyun Suk
    • Journal of Korean Society on Water Environment
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    • v.26 no.5
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    • pp.822-833
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    • 2010
  • Temperature increase due to climate changes causes change of water temperature in rivers which results in change of water quality etc. and the change of river ecosystem has a great impact on human life. Analyzing the impact of current climate changes on air and water temperature is an important thing in adapting to the climate changes. This study examined the effect of climate changes through analyzing air temperature trend for Nakdong river basin and analyzed the elasticity of air-water temperature to understand the effect of climate changes on water temperature. For analysis air temperature trend, collecting air temperature data from the National Weather Service on main points in Nakdong river basin, and resampling them at the units of year, season and month, used as data for air temperature trend analysis. Analyzing for elasticity of air-water temperature, the data were collected by the Water Environment Information system for water temperature, while air temperature data were collected at the National Weather Service point nearest in the water temperature point. And using the results of trend analysis and elasticity analysis, the effect of climate changes on water temperature was examined estimating future water temperature in 20 years and 50 years after. It is judged that analysis on mutual impact between factors such as heat budget, precipitation and evapotranspiration on river water temperature affected by climate changes and river water temperature is necessary.

A Study on the Variations on the Types of Korean Women′s Jackets - emphasized on the period from the Liberation in 1945 to 2000 - (한국 여성상의(Jacket)의 변화 고찰 - 1945년∼2000년을 중심으로 -)

  • Lee Sang-Eun;Kim Young-Ran
    • Journal of the Korea Fashion and Costume Design Association
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    • v.6 no.3
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    • pp.153-167
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    • 2004
  • Korea had suffered the colony of Japanese imperialism and the Korean War from the invasion of the external circumstances. Such special situation made new influences on the clothing habits. The types of Korean women clothing could escape from the traditional style that had been maintained for thousands of years. The foreign clothes for Korean women had undergone various changes from the Liberation in 1945. The jackets that had been introduced to Korea at the Enlightenment period had become popular outfits for men. The jackets made big influences on the changes such as the social advances for women from the times background of the Liberation. The jackets possess very important meaning for the changes in the diffusion of feminism and fashion. Therefore, this research tries to investigate the forms, silhouettes, changes and structures of the jackets such as the locations of the collar, the sleeve, and the waste line. The process of the changes in the style of women jackets is also analyzed from the silhouette and the structure method. The development and changes will be understood of Korean women's jackets. The Korean women's jackets should also be examined further with the history of foreign clothing from now on. The fashion to be introduced from important society cultural phenomena and the Western Europe has been reflected into the changes in the style of Korean female jackets. Also, dramatic changes in the style of clothing indicate that the society had experienced a great deal of changes. It is verified that foreign clothes have been interacted with the stream of times worldwide. After the Liberation, the female jackets become a uniform style which just followed the Western European style. However, a season trend has been announced from the SFAA since 1990. Since then trendy jackets have been detailed more with this chance.

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On the Change of Hydrologic Conditions due to Global Warming : 2. An Analysis of Hydrologic Changes in Daehung Dam Basin using Water Balance Model (지구온난화에 따른 수문환경의 변화와 관련하여 : 2. 물수지 모형을 이용한 대청댐 상류 유역 수문환경의 변화 분석)

  • An, Jae-Hyeon;Yun, Yong-Nam;Yu, Cheol-Sang
    • Journal of Korea Water Resources Association
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    • v.34 no.5
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    • pp.511-519
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    • 2001
  • Global warming has begun since the industrial revolution and it is getting worse recently. Even though the increase of greenhouse gases such as $CO_2$is thought to be the main cause for glogal warming, its impact on global climate has not been revealed clearly in rather quantitative manners. The objective of this research is to predict the hydrological environment changes in the Daechung Dam basin due to the global warming. A mesoscale atmospheric/hydrologic model (IRSHAM96 model) is used to predict the possible changes in precipitation and temperature in the Daechun Dam basin. The simulation results of IRSHAM96 model and a conceptual water balance model are used to analyze the changes in soil moisture, evapotranspiration and runoff in the Daechung Dam basin. From the simulation results using the water balance model for 1x$CO_2$and 2x$CO_2$situations, it has been found that the runoff would be decreased in dry season, but increased in wet season due to the global warming. Therefore, it is predicted that the frequency of drought and flood occurrences in the Daechung Dam basin would be increased in 2x$CO_2$condition.

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