• Title/Summary/Keyword: 직달

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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.

The study of the solar radiation emitted per hour in Incheon applied in load calculation programs (부하계산 프로그램에서 적용되는 인천지역의 시간당 일사량에 관한 연구)

  • Yoo, Ho-Chun;Lee, Seon-Dong
    • Journal of the Korean Solar Energy Society
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    • v.30 no.6
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    • pp.108-117
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    • 2010
  • Although many researches of simulation programs to predict climate under the current climate change have been performed but more detailed studies of weather date which might influence the load of buildings seem insufficient. In this study, in Incheon are analyzed IES (Integrated Environmental Solutions)6.0, Ecotect 2010, EnergyPlus v4.0's IWEC file and ISO-TRY, the Korean standard weather data provided by the Korean Solar Energy Society for direct normal radiation which is used in load calculation programs. The results show that the radiation of the programs is the same as that of direct normal radiation per month but has a mere difference, compared with the radiation per hour and IWEC has also 77.12% when compared with ISO-TRY, meaning that it could affect load values of buildings when applied to them. And in case of ISO-TRY, it could be judged that the application of test reference year applied by the data measured has higher reliability than IWEC file.

A Basic Study on Urban Radiation Heat Transfer (도시의 방사전열에 관한 기초 연구)

  • Kim, C.M.
    • Journal of the Korean Solar Energy Society
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    • v.22 no.4
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    • pp.35-43
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    • 2002
  • This research makes that quantitative radiation property of an actual town ward is obtained in quest of the parameter with regard to a radiation heat transfer property and set up several town ward models that reproduced a solid form of a city along the attribute of the city. A regular trend possibility that is able to evaluate a radiation characteristics of a town ward quantitatively from a town ward guideline and confirmation that is produced about each parameter as a result of a numerical value simulation it obtained. This research shot a coefficient of Gebhart's emission absorption. sky radiation absorption rate direct solar radiation absorption rate the parameter with regard to a radiation heat transfer characteristics of a town ward in each town ward model and a volume rate of a town ward advances case study under regular such condition and shot the absorption rate, direct and others days and calculated an absorption rate and checked about the relation between a town ward and each radiation heat transfer property of a city.

A Study on the Analysis of Solar Radiation Characteristics on a High Elevated Area (고지대 일사량 특성분석에 관한 연구)

  • Jo, Dok-Ki;Kang, Young-Heack;Auh, Chung-Moo
    • Journal of the Korean Solar Energy Society
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    • v.23 no.3
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    • pp.23-28
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    • 2003
  • The purpose of this study is to procure basic data to be used for solar power plant and concentrating collector designs. Site elevation is one of the major factors which influences the incoming insolation to the earth surface. Because the nonpermanent gases such as ozone, water vapor are unmixed components of the atmosphere and their concentrations are the function of height, the site elevation effects the relative proportion of the atmospheric constituents. We have measured solar radiation on Jiri Mt. (1,400m) and in Gurye area(115m) at the near same latitude. These values were then compared to obtain their characteristics and to investigate the potential for the solar utilization for both high and low elevated areas. From the experimental results, we concluded that 1) Daily mean horizontal global radiation and normal beam radiation on Mt. Jiri are 9.5%, and 35.3% higher than Gurye area respectively for a clear day. 2) A significant difference in atmospheric clearness index is observed between Mt. Jiri and Gurye areas.

A Study on the Optimal Installation of Solar Photovoltaic System in Korea (국내 태양광발전시스템의 최적 설치에 관한 연구)

  • Jo, Dok-Ki;Kang, Yong-Heack;Lee, Euy-Joon;Auh, Chung-Moo
    • Journal of the Korean Solar Energy Society
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    • v.24 no.3
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    • pp.19-25
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    • 2004
  • The measured solar radiation incident on tilted surfaces by all directions has been widely used as important solar radiation data in installing photovoltaic modules. To maximize the incident beam radiation, the slope, which is the angle between the plane of the surface in question and the horizontal, an4 the solar azimuth angles are needed for these solar photovoltaic systems. This is because the performance of the solar photovoltaic systems is much affected by angle and direction of incident rays. Recognizing those factors mentioned above are of importance, actual experiment has been performed in this research to obtain the an91e of inclination with which the maximum incident rays can be absorbed. The results obtained in this research could be used in installing optimal photovoltaic modules.

A recent case of an interesting foreign body in the bronchus (최근 본교실에서 경험한 흥미있는 기관지이물에 대하여)

  • 이양선;지중민;송재권;김정도
    • Proceedings of the KOR-BRONCHOESO Conference
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    • 1976.06a
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    • pp.89.1-89
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    • 1976
  • The foreign bodies in the food passage and airway are very important in the Otolaryngological field, and practically there are many reports of them. Also the kinds of these foreign bodies are variable and almost all things around us are likely to be foreign bodies by momentary mistake. According to kinds and locations, clinicians often make mistakes in diagnosis with other physical examination except endoscopy, so foreign body was impacted for a long time and sometimes it may bring a grave outcome to the patient. The authors have recently experienced, in a 13-year-old boy, a pink-colored plastic pencil cap in the right main bronchus which was very similar to the color and shape of the bronchial lumen, and so we had some difficulty in removal of it. This is the report of clinical findings on this case along with literature review.

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Comparative Analysis of Decomposition Models with Site-fitted Coefficients for Seoul (서울지역 지역계수가 적용된 직산분리 모델의 성능 비교)

  • Seo, Dong-Hyun;Kim, Hye-Jin
    • Journal of the Korean Solar Energy Society
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    • v.39 no.3
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    • pp.91-102
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    • 2019
  • Decomposition models are essential in TMY development and solar energy system design. Up until recently, only a few decomposition model related researches are implemented in Korea due to lack of measured direct normal solar irradiance. In contrast, numerous researches have been conducted in various countries, and some quasi-universal composition models have been recommended by several papers. In this research, three decomposition models - Watanabe model, Reindl-2 model and Engerer1 model - are selected and their site-fitted coefficients are developed using measured direct normal solar irradiance in Seoul. R-squared, RMSE, MBE of the site-fitted models are compared with the case of original coefficients and then each other. The comparison result shows that the Reindl-2 model with site-fitted coefficients is best suitable for Seoul. Further researches will be conducted to find the best model using more various measured data of Korean cities and site-fitting methods.

Correlation Analysis between solar power generation and weather variables (태양광 발전량과 기상변수간 상관관계 분석)

  • Yoo, Hyun-jae;Gong, Seung-jun;Kim, Jong-min
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2022.05a
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    • pp.704-706
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    • 2022
  • In this study, we analyzed the correlation between the amount of photovoltaic power generation and the factors of meteorological changes. A total of 52,561 data were used in the correlation analysis from January 2018 to January 2020, and the variables used in the correlation analysis were time, horizontal plane scattering solar radiation, direct solar radiation, wind velocity, and relative humidity. The temperature was used. Based on this data, we used the Google Colab platform to analyze the correlation, and the analysis revealed whether there was a correlation between solar power and meteorological change factors.

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Attenuation of the Atmospheric Aerosol Transmissivity due to Air Pollution (대기오염에 의한 대기투과도 감쇠에 대한 연구)

  • Kim, Yoo-Keun;Lee, Hwa-Woon;Lee, Yong-Seob
    • Journal of Korean Society for Atmospheric Environment
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    • v.11 no.E
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    • pp.23-29
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    • 1995
  • Relationship between atmospheric aerosol transmissivity and air pollution was analyzed using observed data in a large industrial city, Pusan, Korea. The atmospheric aerosol transmissivity predicted by method of present study in Pusan was assessed by the method of Yamamoto et al.(1968) in order to set up an empirical model to predict the transmissivity using the various meteorological parameters and air pollution. As a result, good correlation between these tow method re observed. Thus, it is possible to conclude that the parameterization of air pollution suggested by this study is another method to give reliable estimate of atmospheric aerosol transmissivity and direct solar irradiance in Pusan.

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Comparative Studies on Heating and Cooling Loads' of a Building Varied by Annual Weather Data (연도별 기상데이터를 활용한 건물의 냉.난방부하 특성 비교)

  • Lee, Ji-Hoon;Hwang, Kwang-Il
    • Journal of Navigation and Port Research
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    • v.35 no.3
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    • pp.265-270
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    • 2011
  • The purpose of this study is to compare and analyze the differences of a building's heating and cooling loads depending on the weather variation. Followings are the results. The temperature, humidity and wind speeds of standard year are bigger than those of 2006~2009. The 2006~2009's total horizontal solar irradiance is greater than that of standard year, and the direct solar irradiance of standard year is bigger in winter and vice versa in summer. As results of simulation on heating and cooling loads, it is difficult to find out the bilateral influences between maximum thermal loads and annual's. The equivalent-time operating ratio(EOR) is defined on this study to estimate the differences between year and year, and the EOR of standard year shows low value comparing to 2006~2009 years'.