• Journal of the Korean Solar Energy Society
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• v.25 no.3
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• pp.1-9
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• 2005

The purpose of this paper was to analyze the influence of radiation and convection component separated from surface heat combined transfer coefficient on dynamic Heat load simulation. In general, it was not considered the mutual radiation of walls that heat load simulation calculated by surface combined heat transfer coefficient. In order to solve this problem, we had developed new simulation program to calculate radiation heat transfer and convection heat transfer respectively, and verified the influence of radiation component with this new program, in indoor heat transfer process.

• 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.

• Journal of the Korean Solar Energy Society
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• v.32 no.2
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• pp.28-34
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• 2012

It is necessary to estimate the regression coefficients in order to predict the daily global radiation on a horizontal surface. Therefore 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 hours of bright sunshine. Particularly, the multiple linear 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.

• Journal of the Korean Solar Energy Society
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• v.31 no.4
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• pp.27-33
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• 2011

To find effective way of the production of distilled water for drought and flood with solar radiation, three boxes were made same base each 1000mm ${\times} $1000mm and tops are 45 degree. Individual boxes contained the sea water, rain water and surface water were placed at the same location and same time. Condensation of each box has been compared. On clear day production of distilled water in the box with sea water was 36% and 32% less than boxes with rain water and surface water. The maximum condensation reached when the temperature of the top and bottom parts are equal. As concentration of sea water increased production of distilled water was decreased. In the box with sea water, the surface temperature was lower than 3cm below the surface. Optimum collector area for producing distilled water 2000ml of these three boxes were $3.75m^2$

• Journal of the Korean Solar Energy Society
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• v.25 no.1
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• pp.35-44
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• 2005

The absorbing rate of solar irradiation on the surface of an absorbing tube in a glass evacuated solar collector is numerically investigated. Four different shapes of the absorbing tubes are considered, and the absorbed solar irradiation on the surface is calculated for several distances between the absorbing tubes and the incidence angle of solar beam radiation. From the calculation, it is known that the absorbing rate of solar irradiation on the tube surfaces depends upon the shape and the arrangement of absorbing tube and the incidence angle.

• Atmosphere
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• v.27 no.3
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• pp.331-344
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• 2017

Solar energy is calculated using high-resolution digital elevation model (DEM). In focus on Seoul metropolitan area, correction coefficients of direct and diffuse solar energy with the topographic effect are calculated from DEM with 1720, 900, 450, 90 and 30 spatial resolutions ($m{\times}m$), respectively. The solar energy on the real surface with high-resolution is corrected using by the correction coefficients with topographic effect from the solar energy on horizontal surface with lower resolution. Consequently, the solar energy on the real surface is more detailed distribution than those of horizontal surface. In particular, the topographic effect in the winter is larger than summer because of larger solar zenith angle in winter. In Seoul metropolitan area, the monthly mean topographic effects are more than 200% in winter and within 40% in summer. And annual topographic effects are negative role with more than -60% and positive role with below 40%, respectively. As a result, topographic effect on real surface is not a negligible factor when calculating and analyzing solar energy using regional and global models.

• Journal of Institute of Convergence Technology
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• v.10 no.1
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• pp.13-17
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• 2020

Among the factors that must be taken into account when using thermal imaging cameras that are expanding their application to various fields, a basic study was conducted focusing on temperature on the effect of solar radiation on the photographed thermal image. Through all experiments, in order to use an image taken with a thermal imaging camera for an object installed or located outdoors, a separate temperature correction according to the size of solar radiation or a separate device to block the effect of solar radiation must be additionally installed. Since the temperature of the same object may vary in the thermal image taken indoors or outdoors, it is necessary to calibrate it through comparison with other temperatures as a reference point. In the case of measuring the temperature of a glossy surface such as metal indoors with a thermal imaging camera, it was confirmed that an environment that can remove the light reflection effect by the glossy surface must be constructed and photographed.

• Journal of the Korean Solar Energy Society
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• v.25 no.2
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• pp.9-17
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• 2005

Images taken by geostationary satellite may be used to estimate solar irradiance fluxes at earth's surface. It is based on the empirical correlation between a satellite derived cloud index and the irradiance at the ground. For the validation, estimated solar radiation fluxes are compared with observed solar radiation fluxes at 16 sites over the Korean peninsular from January 1982 to December 2004. Estimated solar radiation fluxes show reliable results for estimating the global radiation with average deviation of -7.8 to +7.0% from the measured values and the yearly averaged horizontal global insolation of Korean peninsula was turned out to be $3.56kW/m^{2}/day$.

• Ocean and Polar Research
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• v.34 no.1
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• pp.73-83
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• 2012

Antarctica is very sensitive to climate change but the number of stations is not sufficient to accurately analyze climate change in this regoin. Model reanalysis data supplements the lack of observation and can be used as long term data to verify climate change. In this study, the 20CR (Twentieth Century Reanalysis) Project data from NCEP/NCAR and monthly mean data (temperature, solar radiation and longwave radiation) from 1871 to 2008, was used to analyze the temperature trend and change in radiation. The 20CR data was used to validate the observation data from Antarctica since 1950 and the correlation coefficients between these data were determined to be over 0.95 at all stations. The temperature increased by approximately $0.23^{\circ}C$/decade during the study period and over $0.20^{\circ}C$/decade over all of the months. This increasing trend was observed throughout the Antarctica and a slight increase was observed in the Antarctic Peninsula. In addition, solar radiation (surface) and longwave radiation (surface and top of atmosphere) trends correlated with the increase in temperature. As a result, outgoing longwave radiation at the surface is attenuated by atmospheric water vapor or clouds and radiation at the top of the atmosphere was reduced. In addition, the absorbed energy in the atmosphere increases the temperature of the atmosphere and surface, and then the heated surface emits more longwave radiation. Eventually these processes are repeated in a positive feedback loop, which results in a continuous rise in temperature.

• Journal of the Korean Solar Energy Society
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• v.26 no.4
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• pp.109-118
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• 2006

The tree is regarded as an sustainable architectural outdoor design element which reduce urban heat island effect by its solar shading and evapotranspiration. This study carried out field observations of measuring thermal environment of selected tree and its ambience to determine passive cooling effects. Results from the field observations are as below; Tree-shading effect to the thermal environment can not be properly evaluated by merely measuring air temperature differences between tree-shaded space and unshaded space for the maximum temperature difference is less than $1.5^{\circ}C$. The differences of longwave radiation and shortwave radiation between tree-shaded space and unshaded space are measured. Shortwave radiation is considered as a main thermal comfort determining factor for the difference of the shortwave radiation is much bigger than that of longwave radiation. By thermal infrared image analysis, the surface temperature of the tree under strong solar radiation is measured same as ambient air temperature. By which the evapotranspiration is considered to retard tree surface temperature raising effectively.