• Proceedings of the Optical Society of Korea Conference
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• 2009.02a
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• pp.293-294
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• 2009

The spectral responsivity of solar cells has been measured under high background irradiance using an LED-based differential spectral responsivity Comparator (DSR-C). The comparator developed is fully automated and has some advantages: It does not need a chopper to modulate the light. Unlike the conventional method, it does not require a monochromator to select wavelength. It covers a wavelength range up to 1200 nm. The wavelength range of the comparator is limited by the spectral power distribution of the LEDs and the spectral responsivity of the standard detector. An active temperature control was utilized to meet the specified standard conditions of solar cell test. This work shows the effect of different levels of background irradiance on the spectral responsivity and the importance of same background irradiance for solar cell test as specified by the corresponding standard.

• Journal of the Korean Solar Energy Society
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• v.32 no.4
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• pp.82-89
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• 2012

This study is on the thermal flow analysis to select an optimal shape of solar lamp bank. Solar Lamp bank is designed by the lamp bank design program based on point light source theory. The reliability of the program for lamp bank design is verified through irradiance variation experiments of a kind of lamp according to horizontal distance. Solar lamp bank facilitates heat distribution and satisfies the irradiance in the three wave length which test guidelines require. Among the 4 kinds of lamp bank, since lamp bank type D satisfies uniformity ${\pm}10%$ and also doesn't exceed total irradiance 1,232 $W/m^2$, type D is finally selected.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.18 no.4
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• pp.457-467
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• 1993

One of the important statistical quantities for optical waves through random media is the probability distribution of irradiance. From phenomenological models, several distribution functions have been proposed. In this paper, irradiance data are obtained by computer simulation, and by comparing the proposed distribution functions with simulation data by the moment method, the histogram method, and the $x^2$-test, the validity of each distribution function is investigated.

• Journal of Plant Biology
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• v.36 no.3
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• pp.219-224
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• 1993

The effects of environmental factors on the growth of Enteromorpha compressa germlings from Daeyulri (34$^{\circ}$36'N; 127$^{\circ}$47'E), the southern cost of Korea were examined in laboratory culture through combinations of irradiance and salinity and temperature and salinity. They showed a maximum growth rate at 125 $\mu$E.m-2.s-1 and 32$\textperthousand$ of irradiance and salinity combination, and at 15$^{\circ}C$ and 32% of temperature and salinity combination. Optimal parameters for the growth of germlings were 15$^{\circ}C$, 125 $\mu$E.m-2s-1 and 32$\textperthousand$. The germlings of E. compressa were survived in a wide range of irradiance, temperature and salinity levels, even though they had relatively low irradiance optimum. In the field E. compressa occurred commonly during autumn and spring seasons and disappeared in summer, except for particular habitats. This may be caused by the salinity and water temperature of this area rarely drop below 26$\textperthousand$ and 8$^{\circ}C$ during winter. A broad tolerance to environmental and rapid growth of germlings made them a wide geographical distribution over the world and a survival in both the upper and lower intertidal zones.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.6
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• pp.703-710
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• 2009

The spectral irradiance and underwater transmission characteristics of a combined high-luminance light-emitting diode (LED) lights have been studied to evaluate suitable light sources for fishing lamps of the next generation. The wavelengths at which the irradiance was maximum were changed from 473, 501, 525, and 465 nm for blue, peacock blue, green, and white LED light to 475, 504 and 528 nm for [$F_{WB}$], [$F_{PB}$] and [$F_{GB}$] combined LED lights, respectively. If the irradiance characteristics at 400-700 nm wavelengths are set as 100%, the irradiance rates at 450-499 nm and 500-549 nm were decreased from 82.4% and 56% for blue, peacock blue LED light to 60.0%, 38.5% for [$F_{WB}$], [$F_{WP}$] combined LED lights. The underwater transmission characteristics of the combined LED lights were superior in the order [$F_{WB}$], [$F_{BP}$], [$F_{GB}$] in optical water type I; [$F_{WB}$], [$F_{PB}$], [$F_{GP}$] in optical water type II-III; and [$F_{GP}$], [$F_{WP}$], [$F_{PB}$] in optical water type 1. Setting the 10m depth underwater transmission characteristics of the combined LED lights in optical water type I at 100%, the transmission of water types II, III and 1 drops to 29.5%, 8.0% and 2.2%. Based on the distribution of spectral irradiance and underwater transmission characteristics calculated in optical water types II-III, where was the jigging ground for fishing lamps, the [$F_{WB}]$ and [$F_{GP}$] combined LED lights can be used as a suitable light sources for fishing lamps of the next generation.

• Proceedings of the KIEE Conference
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• summer
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• pp.548-550
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• 2004

This paper suggests a methodology for calculation of photovoltaic(PV) generation system output using probability distribution function, PV way efficiency and PV system design Parameters. Long term irradiance recorded for every hour of the day for 11 years were used. For goodness-fit test, several distribution functions are tested by Kolmogorov- Smirnov(K-S) test. And the calculated generation output is compared with that of CMS(Centered Monitoring System), which can monitoring PV generation output of each PV generation site.

• Journal of computational fluids engineering
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• v.17 no.3
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• pp.45-52
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• 2012

This paper is a study on the design of the solar lamp bank which is a very important part of the solar simulator with the commercial metal halide lamps and infrared lamps. Lamp Bank is designed by the lamp bank design program based on point light source theory. The reliability of the program for lamp bank design is verified through irradiance variation experiments of a kind of lamp according to horizontal distance. Solar lamp bank facilitates heat distribution and satisfies the irradiance in the three wave length which test guidelines require. The shape of the ceiling board next to the lamp bank to promote the lamp cooling efficiency and to reduce temperature deviation and air velocity deviation in the chamber is so creative. The ceiling board of partial closed type is the best among several types.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.1
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• pp.45-50
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• 1981

Diurnal changes in leaf stomatal resistances were measured on leaf positions and both surfaces to investigate the stomatal response to irradiance in wheat, var. Chokwang and barley, var. Dongbori 1. Stomatal frequency and size were also determined to explain the control mechanism of gas exchanges in two species. The leaf diffusive resistances of two species decreased, as the sun rose, to minimum at 10 to 11 o'clock a.m. and increased gradually in the afternoon, even faster at sunset. As the adaxial irradiance increased, stomatal resistances decreased sensitively in the range of 30uEm$^{-2}$ㆍsec$^{-1}$ to 150uEm$^{-2}$ㆍsec$^{-1}$ quantum flux density. The stomatal opening of the abaxial surface began at lower irradiance and was completed earlier than the adaxial surface. The adaxial irradiances decreased in order of leaf position, flag, the 2nd, the 3rd leaf, and the stomatal resistances increased in the same order. Even under the same irradiance, the stomatal resistance of lower leaves were higher than those of upper leaves. The stomatal frequencies of lower leaves were less, but the stomatal size was greater than those of upper leaves. Consequently, the relative leaf area occupied by stomatal pores were constant among leaf positions in two species.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.54 no.4
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• pp.188-194
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• 2005

There are many factors that affect on the system output of Photovoltaic(PV) power generation; the variation of solar radiation, temperature, energy conversion efficiency of solar cell etc. This paper suggests a methodology for calculation of PV generation output using the probability distribution function of irradiance, PV array efficiency and revision factors of solar cell conversion efficiency. Long-term irradiance data recorded every hour of the day for 11 years were used. For goodness-fit test, several distribution (unctions are tested by Kolmogorov-Smirnov(K-S) method. The calculated generation output with or without revision factors of conversion efficiency is compared with that of CMS (Centered Monitoring System), which can monitor PV generation output of each PV generation site.

• Korean Journal of Agricultural and Forest Meteorology
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• v.15 no.4
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• pp.291-297
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• 2013

Automated weather stations were installed at 9 locations with, three different elevations, (i.e., 50m, 100m, and 300m a.s.l.) with different slope and aspect in a small watershed ($50km^2$ area). Air temperature at 1500 LST and solar radiation accumulated for 1100-1500 LST were collected from January to December 2012. Topography of the study area was defined by a $30{\times}30$ m digital elevation model (DEM) grid. Accumulated solar irradiance was calculated for each location with the spatially averaged slope and aspect of surrounding circles with 5, 10, 15, 20, 25, and 30 grid cell radii, respectively. The 1500 LST air temperature from clear sky conditions with zero cloud amount was regressed to the 1100-1500 LST solar irradiance at 9 locations. We found the highest coefficient of determination ($r^2$ = 0.544) at 25 grid cell radius and the temperature variation in this study was explained by Y = 0.8309X + 0.0438, where Y is 1500 LST temperature (in $^{\circ}C$) and X is 1100-1500 LST accumulated solar irradiance (in $MJ/m^2$).