• Journal of Climate Change Research
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• v.1 no.2
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• pp.147-161
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• 2010

The temporal and spatial distributions of surface solar radiation were calculated by the one layer solar radiative transfer model(GWNU) which was corrected by multi layer Line-by-Line(LBL) model during 2009 in South Korea. The aerosol optical thickness, ozone amount, cloud fraction and total precipitable water were used as the input data for GWNU model run and they were retrieved from Moderate Resolution Imaging Spectrometer(MODIS), Ozone Monitoring Instrument(OMI), MTSAT-1R satellite data and the Regional Data Assimilation Prediction System(RDAPS) model result, respectively. The surface solar radiation was calculated with 4 km spatial resolution in South Korea region using the GWNU model and the results were compared with surface measurement(by pyranometer) data of 22 KMA solar sites. The maximum values(more than $5,400MJ/m^2$) of model calculated annual solar radiation were found in Andong, Daegu and Jinju regions and these results were corresponded with the MTSAT-1R cloud amount data. However, the spatial distribution of surface measurement data was comparatively different from the model calculation because of the insufficient correction and management problems for the sites instruments(pyranometer).

• Journal of the Korean Society of Tobacco Science
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• v.17 no.1
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• pp.15-19
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• 1995

This study was made of the effects from exposure to air temperature and amount of solar radiation during the wilting period on the sunburn of burley tobacco. Tobacco stalks were cult with one hour interval from 8:00 to 16:00, and were left on the field to expose to weather, and tobacco single leaf placed under 4 temperatures regimes in indoor. Sun-burn of the leaves was occurred when the leaves were exposed to temperature higher than 33$^{\circ}C$, and to solar radiation more than 800w/$m^2$ between 11:00-15:00 in a day during the curing season. The leaf temperature was increased until 52$^{\circ}C$ under the weather condition. The tobacco leaves were also burned without solar radiation when the leaves were exposed to high temperature until 5$0^{\circ}C$ of leaf temperature. Sun-bum was increased at upper leaves and at higher moisture content of leaf.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.2
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• pp.1-9
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• 2011

Daylight provides residents with good visual environment. And available daylight in inside provides positive influence on psychological and physiological aspects. Also, sunlight can be converted directly into electricity using PV(photovoltaic) power generation. This study was to analyze characteristics of daylight distributions, calculate an amount of solar radiation and a PV power generation on the building facade using Radiance and Ecotect simulation programs. Ultimately, the purpose of this study is to verify the applicability of Blind PV systems.

• New & Renewable Energy
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• v.9 no.2
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• pp.15-22
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• 2013

The solar energy are an infinite source of energy and a clean energy without secondary pollution. The global solar energy reaching the earth's surface can be calculated easily according to the change of latitude, altitude, and sloped surface depending on the amount of the actual state of the atmosphere and clouds. The high-resolution solar-meteorological resource map with 1km resolution was developed in 2011 based on GWNU (Gangneung-Wonju National University) solar radiation model with complex terrain. The very high resolution solar energy map can be calculated and analyzed in Seoul and Eunpyung with topological effect using by 1km solar-meteorological resources map, respectively. Seoul DEM (Digital Elevation Model) have 10m resolution from NGII (National Geographic Information Institute) and Eunpyeong new town DSM (Digital Surface Model) have 1m spatial resolution from lidar observations. The solar energy have small differences according to the local mountainous terrain and residential area. The maximum bias have up to 20% and 16% in Seoul and Eunpyung new town, respectively. Small differences are that limited area with resolutions. As a result, the solar energy can calculate precisely using solar radiation model with topological effect by digital elevation data and its results can be used as the basis data for the photovoltaic and solar thermal generation.

• Journal of the Korean housing association
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• v.25 no.6
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• pp.49-56
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• 2014

In this study, there is a purpose of using the GIS DB built in DEM, by analyzing the physical characteristics of the building site Yangdong village, to determine the spatial structure of the village. In order to understand the targeted spatial structure of Yangdong Village, the building site was analyzed separately by type and position. Through analysis it is clear the selection of building site relates to the slope and aspect that aquires the most solar radiation in Yangdong Village. This study shows that the amount of solar radiation in the terrain is unfavorable in parts of the village because slope and elevation affect the selection of the building site. That is, this village is confirmed to be influenced by solar radiation, according to slope and elevation, based on how the Yangdong Village is configured. And, while overcoming the adverse conditions to make the most, the village is formed according to the natural environmental conditions.

• Ocean and Polar Research
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• v.26 no.3
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• pp.439-451
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• 2004

Total solar irradiance (750), total UV irradiunce (TUV) and erythemal UV irradiance (EUV) measured at King Sejong station $(62.22^{\circ}S,\;58.78^{\circ}W)$ in west Antarctica have been used together with total ozone, cloud amount and snow cover to examine the effects of ozone, cloud and snow surface on these surface solar inadiunce over the period of 1998-2003. The data of three solar components for each scan were grouped by cloud amount, n in oktas $(0{\leq}n<3,\;3{\leq}n<4,\;4{\leq}n<5,\;5{\leq}n<6,\;6{\leq}n<7\;and\;7{\leq}n<8)$ and plotted against solar zenith angle (SZA) over the range of $45^{\circ}\;to\;75^{\circ}$. The radiation amplification factor (RAE) is used to quantify ozone effect on EUV. RAF of EUV decreases from 1.51 to 0.94 under clear skies but increases from 0.94 to 1.85 under cloudy skies as SZA increases, and decreases from 1.51 to 1.01 as cloud amount increases. The effects of cloud amount and snow surface on EUV are estimated as a function of SZA and cloud amount after normalization of the data to the reference total ozone of 300 DU. In order to analyse the transmission of solar radiation by cloud, regression analyses have been performed for the maximum values of solar irradiance on clear sky conditions $(0{\leq}n<3)$ and the mean values on cloudy conditions, respectively. The maximum regression values for the clear sky cases were taken to represent minimum aerosol conditions fur the site and thus appropriate for use as a normalization (reference) factor for the other regressions. The overall features for the transmission of the three solar components show a relatively high values around SZAs of $55^{\circ}\;and\;60^{\circ}$ under all sky conditions and cloud amounts $4{\leq}n<5$ and $5{\leq}n<6$. The transmission is, in general, the largest in TUV and the smallest in EUV among the three components of the solar irradiance. If the ground is covered with snow on partly cloudy days $(6{\leq}n<7)$, EUV increases by 20 to 26% compared to snow-free surface around SZA $60^{\circ}-65^{\circ}$, due to multiple reflections and scattering between the surface and the clouds. The relative difference between snow surface and snow-free surface slowly increases from 9% to 20% as total ozone increases from 100 DU to 400 DU under partly cloud conditions $(3{\leq}n<6)$ at SZA $60^{\circ}$. The snow effects on TUV and TSO are relatively high with 32% and 34%, respectively, under clear sky conditions, while the effects changes to 36% and 20% for TUV and TSO, respectively, as cloud amount increases.

• The Transactions of the Korean Institute of Power Electronics
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• v.26 no.1
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• pp.38-45
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• 2021

The photovoltaic module has the characteristic of changing its output characteristics depending on the amount of radiation and temperature, where the arrays that connect them in series and parallel also have the same characteristics. These characteristics require the MPPT technique to find the maximum power point. Existing P&O and IncCond cannot find the global maximum power point (GMPP) for partial shading. Moreover, in the case of Improved-GMPPT and Enhanced Search-Skip-Judge-GMPPT, GMPP due to partial shading can be found, but the variation in the open voltage during temperature fluctuations will affect the operation of the Skip and will not be able to perform accurate MPPT operation. In this study, we analyzed the correlation between voltage, current, and power under solar module and array conditions. We also proposed a technique to find the maximum power point even for temperature fluctuations using not only the amount of radiation but also the temperature coefficient. The proposed control technique was verified through simulations and experiments by constructing a 2.5 kW single-phase solar power generation system.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.5
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• pp.712-716
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• 2013

In solar generation, the PV array's azimuth is headed due south and the tilt is generally $33^{\circ}$ in order to acquire maximum generation. However, when installed in a site where there are buildings or other facilities, the azimuth and tilt are adjusted. Yet, when the azimuth and tilt are deviated from due south and $33^{\circ}$, the generation quantity is decreased substantially and currently a method to estimate the decreasing proportion is unavailable. Therefore, in this thesis, an equation on the "change ratio of solar radiation due to the changes in tilt and azimuth" was deduced by utilizing empirical data on the amount of solar radiation received according to the changes of tilt and azimuth and Interpolation. By using this equation, the decreasing proportion of generating quantity due to the installation methods of PV system can be estimated, therefore, it can be usefully utilized when designing and going through feasibility studies for development of solar generation systems.

• Journal of the Korean Solar Energy Society
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• v.27 no.1
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• pp.11-17
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• 2007

The amount of incident rays over inclination according to direction has been widely utilized as important data in installing photovoltaic systems. This is because the performance of the photovoltaic systems in much affected by angle and direction of incident rays. Recognizing that factors mentioned above are of importance, actual experiment on the moving route of the sun have been performed in this research to obtain the angle of inclination with which the maximum incident rays can be absorbed. After all, the standard for designing highly optimized photovoltaic systems will be provided for designers and employees working in the photovoltaic module related industries.

• 한국신재생에너지학회:학술대회논문집
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• 2008.10a
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• pp.174-177
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• 2008

The amount of incident solar rays on inclined surfaces with various directions has 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 12 different stations over the North Korea from 1982 to 2006. 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 application system designer or users.