• KIEAE Journal
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• 제14권2호
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• pp.3-10
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• 2014

Impact by estimation error of hourly horizontal global solar radiation in a weather file on building energy performance was investigated in this study. There are a number of weather parameters in a given weather file, such as dry-bulb, wet-bulb, dew-point temperatures; wind speed and direction; station pressure; and solar radiation. Most of them except for solar radiation can be easily obtained from weather stations located on the sites worldwide. However, most weather stations, also including the ones in South Korea, do not measure solar radiation because the measuring equipment for solar radiation is expensive and difficult to maintain. For this reason, many researchers have studied solar radiation estimation models and suggested to apply them to predict solar radiation for different weather stations in South Korea, where the solar radiation is not measured. However, only a few studies have been conducted to identify the impact caused by estimation errors of various solar radiation models on building energy performance analysis. Therefore, four different weather files using different horizontal global solar radiation data, one using measured global solar radiation, and the other three using estimated global solar radiation models, which are Cloud-cover Radiation Model (CRM), Zhang and Huang Model (ZHM), and Meteorological Radiation Model (MRM) were packed into TRY formatted weather files in this study. These were then used for office building energy simulations to compare their energy consumptions, and the results showed that there were differences in the energy consumptions due to these four different solar radiation data. Additionally, it was found that using hourly solar radiation from the estimation models, which had a similar hourly tendency with the hourly measured solar radiation, was the most important key for precise building energy simulation analysis rather than using the solar models that had the best of the monthly or yearly statistical indices.

• 한국태양에너지학회 논문집
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• 제30권3호
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• pp.1-9
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• 2010

Since the horizontal global radiation and cloud cover are a main factor for designing any solar photovoltaic system, it is necessary to evaluate its characteristics all over the country. The work presented here are the investigation of horizontal global radiation and cloud cover in Korea. The data utilized in the investigation consist of horizontal global radiation and cloud cover collected for 27 years(1982. 12~2008. 12) at measuring stations across the country. The analysis shows that the annual-average daily horizontal global radiation is $3.61\;kWh/m^2$ and the annual-average daily cloud cover is 5.1 in Korea. We also constructed the contour map of cloud cover in Korea by interpolating actually measured data across the country.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 추계학술발표대회 논문집
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• pp.124-129
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• 2011

Since the horizontal global radiation and cloud cover are a main factor for designing any solar energy system, it is necessary to evaluate its characteristics all over the country. The work presented here are the investigation of horizontal global radiation and cloud cover in Korea. The data utilized in the investigation consist of horizontal global radiation and cloud cover collected for 27 years(1982.12~2008.12) at measuring stations across the country. The analysis shows that the annual-average daily horizontal global radiation is $3.61kWh/m^2$ and the annual-average daily cloud cover is 5.1 in Korea. We also constructed the contour map of cloud cover in Korea by interpolating actually measured data across the country.

• 한국태양에너지학회 논문집
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• 제31권3호
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• pp.48-56
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• 2011

Since the horizontal global radiation and hours of bright sunshine are a main factor for designing photovoltaic system, it is necessary to evaluate its characteristics all over the country. The work presented here are the investigation of horizontal global radiation and hours of bright sunshine in Korea. The data utilized in the investigation consist of horizontal global radiation and hours of bright sunshine collected for 28years(1982.12~2009.12) at measuring stations across the country. The analysis shows that the annual-average daily horizontal global radiation is3.61kWh/m2 and the annual-average daily hours of bright sunshineis 5.1 Hrs in Korea. We also constructed the contour map of hours of horizontal global radiation and hours of bright sunshine in Korea by interpolating actually measured data across the country.

• 한국태양에너지학회 논문집
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• 제30권2호
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• pp.16-21
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• 2010

Computer simulation of buildings and solar energy systems are being used increasingly in energy assessments and design. This paper discusses the possibility of using sunshine duration data instead of global hourly solar irradiation (GHSI) data for localities with abundant data on sunshine duration. For six locations in South Korea where global radiation is currently measured, the global radiation was calculated using Sunshine Duration Radiation Model (SDRM), compared and analyzed. Results of SDRM has been compared with the measured data on the coefficients of determination (R2), root-mean-square error (RMSE) and mean bias error (MBE). This study recommends the use of sunshine duration based irradiation models if measured solar radiation data is not available.

• 한국지구과학회지
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• 제38권2호
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• pp.129-140
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• 2017

이 연구에서는 지표 관측 자료와 위성 자료 그리고 GWNU 단층 복사 모델을 이용하여 맑은 상태의 전천 일사량을 계산하였으며, 전운량에 따라 관측 및 모델의 일사량 값을 비교 분석하였다. 연구 자료는 2012년 강릉원주대학교 복사 관측소의 전천 일사량, 기온, 기압, 습도, 에어로졸 등의 관측 자료와 OMI 센서의 오존전량 자료 그리고 구름의 유무 및 전운량을 판단하기 위하여 자동 전운량 장비인 Skyview 자료를 이용하였다. 전운량이 0 할인 맑은 날의 경우 관측 값과 모델 값이 0.98로 높은 상관계수를 나타내었으나 RMSE가 $36.62Wm^{-2}$로 비교적 높게 나타났다. 이는 Skyview 장비가 얇은 구름이나 박무 및 연무 등의 기상상태를 판단하지 못하였기 때문이다. 흐린 날의 경우 구름의 영향을 보정하기 위해 전운량과 두 값의 차에 대한 비율을 이용한 회귀식을 복사 모델에 적용하였으며, 장비의 오탐지를 제외한 경우 상관계수가 0.92로 높은 상관성을 보였으나 RMSE가 $99.50Wm^{-2}$으로 높은 값을 보였다. 더 정확한 분석을 위해서는 직달 성분의 차폐 유무 및 구름 광학 두께를 포함한 다양한 구름 요소의 추가적인 분석이 요구된다. 이 연구결과는 분 또는 시간에 따른 일사량을 산출하여 일사량이 관측되지 않는 지역에서 유용하게 사용될 수 있다.

• 한국연소학회지
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• 제7권1호
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• pp.8-14
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• 2002

Measurements of global emissions, flame radiation and flame dimensions are presented for unconfined turbulent-jet and precessing-jet diffusion flames. Precessing jet flames are characterised by increases in global flame radiation and global flame residence time for methane and propane fuels, however a strong dependency of the NOx emission indices on the fuel type exists. The fuel type dependence is considered to be because soot radiation is more effective than gas-radiation at reducing global flame temperatures relative to adiabatic flame temperatures and reducing the NO production rate.

• 한국태양에너지학회 논문집
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• 제30권4호
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• pp.15-21
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• 2010

Radiation data are the best source of information for estimating average incident radiation. Lacking this or data from nearby locations of similar climate, it is possible to use empirical relation ships to estimate radiation from days of cloudiness. It is necessary to estimate the regression coefficients in order to predict the daily global radiation on a horizontal surface. There fore many different equations have proposed to evaluate them for certain areas. In this work a new correlation has been made to predict the solar radiation for 16 different areas over Korea by estimating the regression coefficients taking into account cloud cover. Particularly, the straight line regression model proposed shows reliable results for estimating the global radiation on a horizontal surface with monthly average deviation of -0.26 to +0.53% and each station annual average deviation of -1.61 to +1.7% from measured values.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.2135-2140
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• 2004

This study represented experimental research on the flat plate solar collector. For the flat plate Solar system, it is sensitive of the Global radiation. In Actually, it suppose to be dependent on the direct radiation. Also, the existing method's factors are depend upon Global radiation in the flat plate collector system. therefore it needs which is depend upon direct radiation. In this experiment, the flat plate collector is used for obtaining the method's factors of the direct radiation. As a result, the correct $({\tau}{\alpha})_e$ is found out for practical value.

• 방사성폐기물학회지
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• 제19권2호
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• pp.243-253
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• 2021

In the dismantling process of a reactor coolant system (RCS) piping, a radiation protection plan should be established to minimize the radiation exposure doses of dismantling workers. Hence, it is necessary to estimate the individual effective dose in the RCS piping dismantling process when decommissioning a nuclear power plant. In this study, the radiation exposure doses of the dismantling workers at different positions was estimated using the MicroShield dose assessment program based on the NUREG/CR-1595 report. The individual effective dose, which is the sum of the effective dose to each tissue considering the working time, was used to estimate the radiation exposure dose. The estimations of the simulation results for all RCS piping dismantling tasks satisfied the dose limits prescribed by the ICRP-60 report. In dismantling the RCS piping of the Kori-1 or Wolsong-1 units in South Korea, the estimation and reduction method for the radiation exposure dose, and the simulated results of this study can be used to implement the radiation safety for optimal dismantling by providing information on the radiation exposure doses of the dismantling workers.