• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1278-1280
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• 2003

Striping is a main factor for imaging spectroradiometer data, which is obtained by multi-sensor scanning on spacecraft. The reason causing stripes and the development of striping removal methods are simply described in this paper, particularly, the principle of Matching Empirical Distribution Functions is introduced in detail. By using this method, some experiments are done to destripe imaging spectrometer data of SZ-3. The result shows that the method of Matching Empirical Distribution Functions is available for destirping Imaging spectroradiometer data of SZ-3, and the quality of image is improved obviously. This will help to process the future similar instruments data.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1-3
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• 2003

In this study, spectroradiometer data were coupled with fluorometer data to find out the best suited bands ratio to monitor the chlorophyll a concentration for inland water. Remote sensing reflectance measurements were used to evaluate the performance of several default ocean color chlorophyll algorithms for SeaWiFS data. This study shows that the chlorophyll a concentration from fluorometer and reflectance from spectroradiometer lies in exploiting the signal provided by the chlorophyll a red absorption peak near 670nm. Two-band ratio based on a ratio of reflectance 670 and 700nm provided a good correlation for a linear model, compare with blue-green two band ratio.

• Journal of Bio-Environment Control
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• v.9 no.4
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• pp.223-229
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• 2000

This study was conducted to analyze the opto-electric characteristics of light-emitting diodes(LED) designed for growth and morphogenesis control of transplant and to quantify the photon flux emittig from LED using a quantum sensor spectroradiometer. Difference in photon flux for blue and red LED between measured by a quantum sensor and measured by a spectroradiometer and numerically integrated was not observed. This result implies a spectroradiometer can be applied to quantify the photon flux emitting from far-red LED, which can not be measured using a quantum sensor. Since photon flux increases in proportion to wavelength, photon flux of LED modules arranged for red and far-red increased in proportion to wavelength, photon flux of LED modules arranged for red and rar-red increased gradually as the number of LED stick emitting far-red in LEd modules increased. Illumination of LED modules arranged for red and far-red decreased as the number of LED stick emitting far-red in LED modules increased. There was no difference in irradiance between LED modules arranged for red and far-red.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.663-665
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• 2003

A field spectroradiometer SE-590 was used to measure the spectral reflectance of water body. The reflectance was calculated as the ratio of surface water radiance to the standard whiteboard radiance nearly measured at the same time. Water samples were taken simultaneously for determining their chlorophyll-a, suspended solid (SS) and transparency. The relationships between those water quality parameters and spectral reflectance were analy zed using stepwise multiple regression to derive optimal prediction models . The multiple regression was also applied to the SE-590 simulated SPOT bands. The SPOT image of the same day was also analyzed using the same method to compare the statistical results. It showed that the multiple regression models using the SE-590 reflectance data got the best water quality prediction results. The evaluated RMS error of chlorophyll-a, SS and transparency of water quality parameters were 0.57 ug/l, 0.2 mg/l and 0.17 m, respectively, and the RMS errors were 0.36 ug/l, 0.49 mg/l and 0.42 m for SPOT data, respectively. The SE-590 simulated SPOT three bands data obtained the worst results and the RMS errors were 1.77 ug/l, 0.49 mg/l and 0.37 m, respectively.

• Journal of Environmental Science International
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• v.30 no.2
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• pp.173-184
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• 2021

Ecological disturbance plants distributed throughout the country are causing a lot of damage to us directly or indirectly in terms of ecology, economy and health. These plants are not easy to manage and remove because they have a strong fertility, and it is very difficult to express them quantitatively. In this study, drone hyperspectral sensor data and Field spectroradiometer were acquired around the experimental area. In order to secure the quality accuracy of the drone hyperspectral image, GPS survey was performed, and a location accuracy of about 17cm was secured. Spectroscopic libraries were constructed for 7 kinds of plants in the experimental area using a Field spectroradiometer, and drone hyperspectral sensors were acquired in August and October, respectively. Spectral data for each plant were calculated from the acquired hyperspectral data, and spectral angles of 0.08 to 0.36 were derived. In most cases, good values of less than 0.5 were obtained, and Ambrosia trifida and Lactuca scariola, which are common in the experimental area, were extracted. As a result, it was found that about 29.6% of Ambrosia trifida and 31.5% of Lactuca scariola spread in October than in August. In the future, it is expected that better results can be obtained for the detection of ecosystem distribution plants if standardized indicators are calculated by constructing a precise spectral angle standard library based on more data.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 1997.12a
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• pp.27-33
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• 1997

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.10 no.2
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• pp.54-62
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• 1996

A multichannel type spectroradiometer which can measure the optical characteristics of light sources was constructed. Our system can be used to measure the optical characteristics of light sources of which the wavelengths are ranging from ultraviolet to infrared(220nm~1100nm)in 16msec. The optical characteristics such as color coordinates, color rendering index, brightness, color difference, etc. was measured and analyzed.

• Proceedings of the KSRS Conference
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• 2008.03a
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• pp.69-73
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• 2008

초분광영상을 이용한 정량적인 분석이나 분광라이브러리를 이용한 목표물의 탐지를 위해서는 복사보정이 필수적이지만 사전 검보정 자료가 없는 센서의 경우 절대 복사 보정을 실시할 수 없다. 본 연구의 목표는 사전 검보정 자료가 없는 지상 초분광 카메라 (SOC700) 영상의 화소값을 spectroradiometer의 radiance로 변환하기 위한 상대 변환계수(gain, offset coefficient)를 산출하고 그 적합성을 판단하는 것이다. 초분광영상의 DN과 동시에 측정된 radiance의 밴드별 선형 회귀분석을 통하여 상대 radiance 변환계수를 산출하였다. 산출된 선형 회귀식의 적합도($R^2$)는 대부분이 0.9 이상으로 매우 양호하였으며 상대 radiance를 이용할 경우 상대 분광반사율 획득이 가능하며 이를 통해 보다 초분광영상에 적합한 정량적인 분석을 할 수 있다.

• Korean Journal of Remote Sensing
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• v.35 no.4
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• pp.609-616
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• 2019

Land surface temperature ($T_s$) is a critical variable for understanding the surface energy exchange between land and atmosphere. Using the data measured from micrometeorological flux towers, three types of $T_s$, obtained using a thermal-infrared radiometer (IRT), a net radiometer, and an equation for sensible heat flux, were compared. The $T_s$ estimated using the net radiometer was highly correlated with the $T_s$ obtained from the IRT. Both values acceptably fit the $T_s$ from the Terra/MODIS (Moderate Resolution Imaging Spectroradiometer)satellite. These results will enhance the measurement of land surface temperatures at various scales. Further, they are useful for understanding land surface energy partitioning to evaluate and develop land surface models and algorithms for satellite remote sensing products associated with surface thermal conditions.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2005.11a
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• pp.523-524
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• 2005