• 제목/요약/키워드: spectroradiometer

검색결과 278건 처리시간 0.037초

A Method to Destripe Imaging Spectroradiometer Data of SZ-3

  • Xiaoxiang, Zhu;Tianxi, Fan;Qian, Huang
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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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.

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Characteristics of Chlorophyll a Absorption in Case 2 Water for Using Remote Sensing Data

  • Islam, Monirul;Sado, Kimiteru
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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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.

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광량자센서와 분광광도계를 이용한 발광다이오우드 광량자속의 정량화 (Quantifying of Photon Flux Emitting from Light-emitting Diodes Using a Quantum Sensor and Spectroradiometer)

  • 김용현;박현수
    • 생물환경조절학회지
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    • 제9권4호
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    • pp.223-229
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    • 2000
  • 식물묘의 생장 및 형태형성 제어용 인공광원으로서 조합광 LED 모듈을 제작하여 조합광 LED모듈의 광전기 특성을 분석하고, 광량자 센서와 분광광도계를 이용하여 LED 모듈로부터 조사된 광량자속에 대한 정량화를 시도하였다. 청색과 적생의 단색광 LED로부터 조사된 광량자속을 광량자센서로 측정한 값과 분광광도계로 측정하여 수치적으로 적분한 값을 qly한 결과 거의 일치하는 것으로 나타났다. 이러한 결과는 광량자센서로서 측정이 불가능한 원적색광 LED로부터의 광량자속 정량화에 분광광도계를 적용될 수 있음을 의미하는 것이다. 적생광에 원적색광을 조사하는 LED스틱의 혼합 비율을 달리한 조합광 LED 모듈의 광량지속은 원적색광을 조사하는 LED 스틱이 증가할수록 조합광 LED의 광량자속이 조금씩 증가하였다. 이러한 결과는 단위에너지당 조사된 광량지수는 파장에 비례해서 증가히기 때문인 것으로 해석된다. 이밖에 적색과 원적색광 LED 스틱의 조합 비율을 달리하였을 때 조합광 LED 모듈의 조도는 비시감도가 매우 낮은 원적색광이 차지하는 비율이 클수록 낮게 나타났다. 한편 적색광과 원적생광의 혼합 정도가 조합광 LED의 복사조도에 미치는 영향은 거의 없는 것으로 나타났다.

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Water Quality Estimation Using Spectroradiometer and SPOT Data

  • Hsiao, Kuo-Hsin;Wu, Chi-Nan;Liao, Tzu-Yi
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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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.

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드론 초분광 스펙트럼과 분광각매퍼를 적용한 생태계교란식물 탐지 (Detection of Ecosystem Distribution Plants using Drone Hyperspectral Spectrum and Spectral Angle Mapper)

  • 김용석
    • 한국환경과학회지
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    • 제30권2호
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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.

Multichannel Type 분광방사측정 시스템의 제작 및 응용에 관한 연구 (A Study on Construction and its Application of Multichannel Type Spectroradiometer)

  • 성연국;백운식
    • 한국조명전기설비학회지:조명전기설비
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    • 제10권2호
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    • pp.54-62
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    • 1996
  • 본 연구에서는 광학계를 설계하고 이미지 센서를 사용하여 자외선 영역에서 근적외선(220nm~1100nm)의 광학적 특성평가를 측정시간 16ms에서 20000ms 범위에서 검지할 수 있도록 하는 시스템을 제작하고 본 시스템의 응용연구를 통해 조명산업 및 표시소자 산업의 연구개발 및 품질관리 평가에 필요한 칼라의 색좌표, 연색성, 휘도, 색차, 색순도, 반사율, 투과율 등을 측정하였다.

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분광측정기를 이용한 초분광카메라 영상의 상대 복사보정 (Relative radiometric calibration for the SOC700 hyperspectral image with spectroradiometer)

  • 신정일;;강성진;이규성
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2008년도 춘계학술대회 논문집
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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.

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Comparison of Land Surface Temperatures from Near-surface Measurement and Satellite-based Product

  • Ryu, Jae-Hyun;Jeong, Hoejeong;Choi, Seonwoong;Lee, Yang-Won;Cho, Jaeil
    • 대한원격탐사학회지
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    • 제35권4호
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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.