• Journal of Bio-Environment Control
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• v.6 no.3
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• pp.176-182
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• 1997

A simulation model for the analysis of the transmissivity of direct and diffuse solar radiation In glasshouse was developed. This model would be applicable to investigate the influences of time of year, orientation and slope of glasshouse, dimensions of the frames used, and latitude of the site on the transmissivity of direct and diffuse solar radiation in single-span or multispan glasshouse. The transmissivity of diffuse solar radiation was 60.4％ for the single-span glass-house. It was independent of both orientation and time of year, During the winter season, the transmissivity of direct solar radiation was 67~69％ for the E-W orientation single-span glasshouse, which was 14~16％ higher than that for the S-N orientation. Oppositely the transmissivity of direct solar radiation for the S-N orientation was higher than that for the E-W orientation. during the autumn season. There was no influence of the latitude In the country on the transmissivity of direct solar radiation.

• KIISE Transactions on Computing Practices
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• v.23 no.11
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• pp.632-640
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• 2017

Although solar insolation is the weather factor with the greatest influence on power generation in photovoltaic systems, the Meterological Agency does not provide solar insolation data for future dates. Therefore, it is essential to research prediction methods for solar insolation to efficiently manage photovoltaic systems. In this study, we propose a Dynamic Piecewise Prediction Model that can be used to predict solar insolation values for future dates based on information from the weather forecast. To improve the predictive accuracy, we dynamically divide the entire data set based on the sun altitude and cloudiness at the time of prediction. The Dynamic Piecewise Prediction Model is developed by applying a polynomial linear regression algorithm on the divided data set. To verify the performance of our proposed model, we compared our model to previous approaches. The result of the comparison shows that the proposed model is superior to previous approaches in that it produces a lower prediction error.

• Journal of Cadastre & Land InformatiX
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• v.48 no.1
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• pp.5-14
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• 2018

Recently the construction of solar plant showed a steady growth in influence of renewable energy policy. It is very important to determine the optimal location and aspect of solar panel using analyzed data of solar radiation to solar plant area beforehand. This study analyzed solar radiation in solar plant area using DEM acquired from UAV geospatial information. Mean solar radiation of 2017 was calculated as $1,474,466W/m^2$ and total solar radiation of 2017 considering solar plant area showed $33,639MW/m^2$ on analyzed result. It is important to analyze monthly solar radiation in aspect of maintenance works of solar plant. Monthly solar radiation of May to July was calculated over $160,000W/m^2$ and that of January to February and November to December showed under $80,000W/m^2$ in monthly solar radiation analysis of solar plant area. Also this study compared with solar radiation being calculated from UAV geospatial information and that of National Institute of Meteorological Sciences. And mean solar radiation of study area showed a little high in comparison with whole country data of National Institute of Meteorological Sciences, because the 93.7% of study area was composed of south aspect. Therefore this study can be applied to calculate solar radiation in new developed solar plant area very quickly using UAV.

• Korean Journal of Remote Sensing
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• v.24 no.6
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• pp.605-612
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• 2008

In this study, we estimate solar surface insolation (SSI) by using physical methods with MTSAT-1R data. SSI is regarded as crucial parameter when interpreting solar-earth energy system, climate change, and agricultural production predict application. Most of SSI estimation model mainly uses ground based-measurement such as pyranometer to tune the constructed model and to validate retrieved SSI data from optical channels. When compared estimated SSI with pyranometer measurements, there are some systemic differences between those instruments. The pyranometer data observed upward-looking hemispherical solid angle and distributed hourly measurements data which are averaged every 2 minute instantaneous observation. Whereas MTSAT-1R channels data are taken instantaneously images at fixed measurement time over scan area, and are pixel-based observation with a much smaller solid angle view. Those temporal discrepancies result from systemic differences can induce validation error. In this study, we adjust hour when estimate SSI to improve the retrieved accurate SSI.

• The Korean Journal of Applied Statistics
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• v.30 no.6
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• pp.1005-1013
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• 2017

In this paper, we investigate the performances of time series models to forecast irradiance that consider weather variables such as temperature, humidity, cloud cover and Global Horizontal Irradiance. We first introduce the time series models and show that regression ARIMAX has the best performance with other models such as ARIMA and multiple regression models.

• The Journal of the Korea Contents Association
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• v.7 no.12
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• pp.218-230
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• 2007

Measured values of solar radiation data have a characteristic that they change almost by the minute, so original data can be massive. Therefore, we need to construct a database which stores and manages history data of solar radiation data systematically. A study of an estimation method of the future change trend is also required. In this paper, we present a data structure in order to store history data of solar radiation data and propose an estimation method for the change trend of solar radiation that applies to a time-series decomposition method. Also, we present the results of experiments based on measured data from 20 domestic cities in Korea.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.1
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• pp.28-36
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• 2023

Solar radiation that is measured at relatively small number of weather stations is one of key inputs to crop models for estimation of crop productivity. Solar radiation products derived from GK-2A and Himawari 8 satellite data have become available, which would allow for preparation of input data to crop models, especially for assessment of crop productivity under an agrivoltaic system where crop and power can be produced at the same time. The objective of this study was to compare the degree of agreement between the solar radiation products obtained from those satellite data. The sub hourly products for solar radiation were collected to prepare their daily summary for the period from May to October in 2020 during which both satellite products for solar radiation were available. Root mean square error (RMSE) and its normalized error (NRMSE) were determined for daily sum of solar radiation. The cumulative values of solar radiation for the study period were also compared to represent the impact of the errors for those products on crop growth simulations. It was found that the data product from the Himawari 8 satellite tended to have smaller values of RMSE and NRMSE than that from the GK-2A satellite. The Himawari 8 satellite product had smaller errors at a large number of weather stations when the cumulative solar radiation was compared with the measurements. This suggests that the use of Himawari 8 satellite products would cause less uncertainty than that of GK2-A products for estimation of crop yield. This merits further studies to apply the Himawari 8 satellites to estimation of solar power generation as well as crop yield under an agrivoltaic system.

• Journal of Bio-Environment Control
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• v.8 no.3
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• pp.202-208
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• 1999

This study was conducted to investigate the effects of the frame ratio and greenhouse length on the transmissivities of direct and diffuse solar radiation in glasshouse using a computer simulation model developed by Kim and Lee(1997). Transmissivity of diffuse solar radiation slightly decreased as the frame ratio increased. There was no effect of number of spans on the transmissivity of diffuse solar radiation at the same frame ratio. In single or multispan glasshouse, transmissivity of direct solar radiation was 1.5-3.0% higher at the frame ratio of 11.3% than those at the frame ratio of 14.9%. Also the transmissivity of direct solar radiation was 1.5-3.0% lower at the frame ratio of 18.3% than those at the frame ratio of 14.9%. Effect of the increased or decreased frame ratio on the transmissivity of direct solar radiation was similar in I-W or S-N glasshouse. Since the high transmissivity of direct solar radiation exerted a beneficial influence upon the plant growth during winter season, the light and endurable structural members were needed to maximize the transmission of solar radiation in glasshouse. Transmissivity of direct solar radiation in I-W or S-N glasshouse did not vary with the length of 24.5m long or more.

• Korean Journal of Agricultural and Forest Meteorology
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• v.13 no.1
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• pp.41-46
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• 2011

Reliable information on the surface solar radiation is indispensable for rebuilding food production system in the famine plagued North Korea. However, transfer of the related modeling technology of South Korea is not possible simply because raw data such as solar radiation or sunshine duration are not available. The objective of this study is restoring solar radiation data at 27 synoptic stations in North Korea by using satellite remote sensing data. We derived relationships between MODIS radiation estimates and the observed solar radiation at 18 locations in South Korea. The relationships were used to adjust the MODIS based radiation data and to restore solar radiation data at those pixels corresponding to the 27 North Korean synoptic stations. Inverse distance weighted averaging of the restored solar radiation data resulted in gridded surfaces of monthly solar radiation for 4 decadal periods (1983-1990, 1991-2000 and 2001-2010), respectively. For a direct application of these products, we produced solar irradiance estimates for each sub-grid cell with a 30 m spacing based on a sun-slope geometry. These products are expected to assist planning of the North Korean agriculture and, if combined with the already prepared South Korean data, can be used for climate change impact assessment across the whole Peninsula.

• Journal of Navigation and Port Research
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• v.35 no.5
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• pp.387-392
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• 2011

The value of Photovoltaic as an independent power supply is small, but the city's carbon emissions reduction and for the reduction of fossil fuel use distributed power is the power source to a very high value. However, according to the weather conditions for solar power generation by power fluctuations because of the size distribution to be effective, the big swing for effectively controlling real-time monitoring should be made. But that depends on solar power generation solar radiation forecasts from the National Weather Service does not need to predict it, and this study, the diffuse sky radiation in the history of the solar radiation in the darkness of the clouds, thick and weather forecasts can be inferred from the atmospheric transmittance to announce this value is calculated to represent each weather forecast solar radiation and solar radiation predicted by substituting the expression And the measured solar radiation and CRM (Cloud Cover Radiation Model) technique with an expression of Kasten and Czeplak irradiation when compared to the calculated predictions were verified.