• Title/Summary/Keyword: 청명도

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Analysis of Solar Radiation Components for the Installation of Solar Thermal System in Korea (국내 태양열시스템 설치를 위한 성분일사량 분석)

  • Jo, Dok-Ki;Kang, Young-Heack
    • Journal of the Korean Solar Energy Society
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    • v.29 no.3
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    • pp.12-18
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    • 2009
  • The Knowledge of the solar radiation components are essential for modeling many solar energy systems. This is particularly the case for applications that concentrate the incident energy to attain high thermodynamic efficiency achievable only at the higher temperatures. In order to estimate the performance of concentrating thermal systems, it is necessary to know the intensity of the beam radiation, as only this component can be concentrated. The Korea Institute of Energy Research(KIER) has began collecting solar radiation component data since January, 2002. KIER's component data will be extensively used by concentrating system users or designers as well as by research institutes. The theoretical analysis of solar radiation as a component has compared with the experimental data obtained by the KIER station. The Result of simulation analysis shows that the annual-average daily diffuse radiation on the horizontal surface is $1,457cal/m^2$ and daily direct radiation on the horizontal surface is $1,632cal/m^2$ for all over the 16 areas in Korea.

Revaluation of Atmospheric Clearness Index in Korea Peninsula (한반도 대기청명도의 재평가)

  • Jo, Dok-Ki;Yun, Chang-Yeol;Kim, Kwang-Deuk;Kang, Yong-Heack
    • 한국태양에너지학회:학술대회논문집
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    • 2009.11a
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    • pp.68-73
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    • 2009
  • Since the atmospheric clearness index is main factor for evaluating atmosphere environment, it is necessary to estimate its characteristics all over the major cities in Korea Peninsula. We have begun collecting clearness index data since 1982 at 16 different cities in South Korea and estimated using empirical forecasting models at 21 different stations over the North Korea from 1982 to 2008. This considerable effort has been made for constructing a standard value from measured data at each city. The new clearness data for global-dimming analysis will be extensively used by evaluating atmospheric environment as well as by solar PV application system designer or users. From the results, we can conclude that. 1) Yearly mean 63.5 % of the atmospheric clearness index was evaluated for clear day all over the 37 cities in Korea Peninsula, 2) Clear day's atmospheric clearness index of spring and summer were 64.6% and 64.8%, and for fall and winter their values were 63.3% and 61.3% respectively in Korea Peninsula.

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PEOPLE Inside (2) - 오랜 현장 경험과 부모로서의 경험치 교육정책에 녹여내${\cdots}$ 노래하는 학교, 줄넘기하는 학생 모토로 공교육 활성화, 부산시 교육감 임혜경

  • 대한결핵협회
    • 보건세계
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    • v.61 no.4
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    • pp.38-40
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    • 2013
  • 2007년부터 교육감 직선제가 시행됨에 따라, 이제 교육 정책을 펼칠 지역 일꾼을 직접 뽑을 수 있게 됐다. 2010 부산시 교육의 책임자로 시민의 선택을 받은 임혜경 교육감은 지난 해 '전국 교육감 공약 이행 및 정보공개 평가'에서 최고 평가를 받았다. 취임 4년차, 그 행보가 돋보이는 임혜경 교육감을 만나보았다. 인터뷰를 위해 찾은 부산시교육청은 청명한 가을 날씨에 길 양쪽으론 가로수가 멋들어진, 옛날의 교정을 연상케 했다. 그리고 가을 햇살 가득한 방, 교육감실에서 인터뷰가 진행되었다. 다음은 임혜경 교육감과의 일문일답.

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Effect of Moisture Content and Density to the Decay of Rice Straw Bale during Storage (볏짚 베일의 함수비와 밀도가 저장 중 부패정도에 미치는 영향)

  • 김종언;박홍제;김경욱
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1999.07a
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    • pp.221-227
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    • 1999
  • 베일러 작업에 있어 작업시의 볏짚의 함수율은 베일러의 작업성, 저장 중에 발생하는 볏짚의 물리적, 화학적 변화 등에 있어 중요한 요소로 작용한다. 국내의 경우 가을철에 청명하고 건조한 날이 많아 볏짚이 빠르게 건조되나 일기가 고르지 못한 경우에는 높은 함수율에서도 작업을 해야할 경우가 생긴다. 높은 함수율에서 작업하는 경우 필연적으로 베일의 질적 저하가 일어나는데 이를 줄이는 방법의 하나로 밀도를 조정하는 방법이 있다. (중략)

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Varietal Difference in Lodging - related Characteristics in Rice (벼 도복관계형질 특성의 품종간 차이)

  • 송동석;김용재;임준택;김진호;이성춘
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.41 no.4
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    • pp.395-404
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    • 1996
  • This experiment was to evaluate the growth characteristics of lodging resistance cultivated at sandbed in rice varieties. Five varieties were used in this studies. The leaf area, leaf dry weight, culm dry weight and total dry weight of cultivated rice seedling at sandbed showed the maximal values at heading stage, but decreased according to growth development. The number of newly developed roots of rice seedlings cultivated at sand pot were the most at the 30 days seedling stage, but those were decreasing at 40 to 45 days seedling stage. Cheongmyungbyeo and Dongjinbyeo showed the most vigor in newly developed roots. The bending moment at breaking of rice internodes were the largest at the 4th node, but decreased at the top internodes. Cheongmyungbyeo and Dongjinbyeo were proved lodging resistant varieties by the bending moment. The weight of culm base was positively correlated with bending moment at breaking of rice culm, but lodging index was negatively correlated weight of culm base and root dry weight, respectively.

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Comparison of the Aroma Components in the Korean Traditional Yakjus. (전통(傳統) 약주(藥酒)의 향기성분(香氣成分) 비교(比較))

  • Jung, Ji-Heun;Jung, Soon-Teck
    • Applied Biological Chemistry
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    • v.30 no.3
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    • pp.264-271
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    • 1987
  • Baikhaju, Nockpaju, Dongdongju and Chungmyungju of the traditional Yakjus - the native alcoholic beverage of Korea - with the different fermentation methods were brewed and the volatile odor components were analized by gas chromatography methods of headspace gas. The general constituent content in them was different a little, and formaldehyde, acetone, acetaldehyde, ethylacetate, ethylalcohol, n-propanol, iso-butanol, iso-amylalcohol, diacetyl and dimethyl sulfide were separated and quantified into the volatile aroma components. The contents of acetaldehyde, ethylacetate and n-propanol were $17{\sim}73ppm$, and iso-amylalcohol were $418{\sim}925ppm$. The contents of formaldehyde and acetone were $0{\sim}2.15ppm$, and that of diacetyl and dimethyl sulfide were $0.032{\sim}1.012ppm$, and $5{\sim}65ppb$.

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Solar Radiation Measurement and Analysis of a High Mountain Area (고산지대의 일사량 특성분석 - 소백산과 그 인접 저지대를 중심으로 -)

  • Jo, Dok-Ki;Lee, Tae-Kyu;Chun, Il-Soo;Jeon, Hong-Seok;Auh, Chung-Moo
    • Solar Energy
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    • v.16 no.2
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    • pp.49-63
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    • 1996
  • Site elavation is one of the major factors which is influencing the incoming insolation. Because nonpermanent gases like ozone, water vapor are unmixed components of the atmosphere and their concentrations are function of height, the site elevation effects the relative proportion of the atmospheric constituents. We have measured solar radiation on Sobaek(1,350m) and in Poonggi area(280m). These values were compared to investigate the their charateristics and the potential for the solar utilization as an alternative energy for both high altitude area and low altitude area. From the results, we conclude that 1) Yearly mean 4,093 $kcal/m^2$. day of the horizontal global radiation in Mt. Sobaek was evaluated for clear day. 2) Insolation on Mt. Sobaek is $6{\sim}7%$ higher than Poonggi area during summer and winter seasons. 3) A significant difference of atomospheric clearness index is observed between Mt. Sobaek and Poonggi area at the same latitude.

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A Detailed Survey of Direct Normal Radiation and Clear-day for the Construction of Solar Concentrating System in Korea (국내 고집광 태양에너지 이용시스템 설치를 위한 법선면 직달일사량과 청명일 정밀조사)

  • Jo, Dok-Ki;Kang, Young-Heack
    • Journal of the Korean Solar Energy Society
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    • v.26 no.3
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    • pp.53-62
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    • 2006
  • Since the direct normal radiation and clear day are a main factor for designing any solar thermal and photovoltaic concentrating system, it is necessary to evaluate its characteristics all over the country. The work presented here are the investigation of direct normal radiation and clear day in Korea. The data utilized in the investigation consist of direct normal radiation collected for 14 years('90. 12${\sim}$2004. 12) and clear-day collected for 23 years($1982{\sim}2004$) at measuring stations across the country. The analysis shows that the annual-average daily direct normal radiation is 5.4 kWh/m2 and the annual-average total clear-day is 92.7 days in Korea. We also constructed the contour map of direct normal radiation and clear-day in Korea by interpolating actually measured data across the country.

Analysis of Global Dimming Appearances Using the Solar Radiation Measurement in Korean Major Cities (태양복사 측정에 의한 주요 도시의 Global Dimming 현상분석)

  • Jo, Dok-Ki;Kang, Young-Heack
    • 한국신재생에너지학회:학술대회논문집
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    • 2008.05a
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    • pp.146-149
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    • 2008
  • Since the atmospheric clearness index is main factor for evaluating global-dimming of atmosphere environment, it is necessary to estimate its characteristics all over the major cities in Korea. We have begun collecting clearness index data since 1982 at 16 different cities and considerable effort has been made for constructing a standard value from measured data at each city. The new clearness data for global-dimming analysis will be extensively used by evaluating atmospheric environment as well as by solar PV application system designer or users. From the results, we can conclude that 1) Yearly mean 61.9 % of the atmospheric clearness index was evaluated for clear day all over 2) A significant difference of atmospheric clearness index is observed between 1982-1989 and1990-1997, 1998-2005 through 16 different cities in Korea.

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Atmospheric Clearness Estimation of Major Cities in Korea Using Empirical forecasting Models (경험적 예측모형을 통한 우리나라 주요 도시의 대기청명도 평가)

  • 조덕기;최인수
    • Journal of the Korean Operations Research and Management Science Society
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    • v.23 no.4
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    • pp.151-169
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    • 1998
  • Since the atmospheric clearness index is one of the main factors for evaluating atmospheric circumstances, it is necessary to estimate its characteristics all over the cities in Korea. This study was focused on the evaluation of atmospheric condition for each 15 cities in terms of respectively or mutually analyzed clearness factor that was predicted on the assumed clear day with the model using factors such as average global insolation. cloud amount, and duration of sunshine measured for two years between 1996 and 1997. The new clearness index data will be extensively used by atmospheric circumstances analysts as well as by solar application designers or users.

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