• 대한원격탐사학회지
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• 제18권4호
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• pp.201-207
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• 2002

복사전달모델과 KOMPSAT-1/OSMI 자료를 이용하여 황사함지 가능성을 조사하였다. 그리고 황사탐지를 위한 OSMI의 특성을 파악하기 위하여 OSMI와 SeaWiFS의 자료를 이용하여 공간 분광분석과 채널별 스펙트럼 분석을 실시하고, 또한 에어로솔 광학두께를 상호 비교하였다. OSMI와 SeaWiFS 자료를 이용한 x축 방향의 분광분석 결과, 865nm에서 분광특성이 비슷함을 알 수 있었고, 채널별 스펙트럼 분석에서는 765nm과 865nm에서 SeaWiFS의 결과와 비슷하여 이 밴드에서의 OSMI 자료의 활용 가능성을 확인할 수 있었다. 이들 밴드를 이용하여 산출한 OSMI의 황사탐지 화상은 MODIS에서 얻어진 화상과 비슷함을 알 수 있었다. 황사 때의 광학두께는 약 0.8~l.0으로 나타났다.

• 항공우주기술
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• 제1권2호
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• pp.132-140
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• 2002

다목적 실용위성 1호의 OSMI 센서의 동작 특성을 이용하여 달을 촬영할 수 있다. 달은 대기가 없고 태양광의 반사율이 일정하기 때문에 OSMI 센서의 방사 보정을 위한 적합한 광원이 될 수 있다. 다목적 실용위성 1호의 정상 운용 과정에서 OSMI를 이용하여 달 촬영을 수행하기 위해서는 비정상적 운용 모드 발생 가능성이 높기 때문에 다목적 실용위성 1호의 운용, 달, 태양의 정보들을 고려한 최적화된 달 촬영 계획이 수립되어야 한다. 하지만 결정하기 위해서 많은 시간이 소비되고 효율성이 떨어지는 단점이 있다. 이에 본 연구에서는 달 촬영을 위한 고속 시뮬레이터를 개발, 구현한다. 시뮬레이터는 OSMI를 이용한 달촬영 가능 시간을 결정하고 영상에 맺힐 달의 좌표, 달의 위상을 결정한다. 다목적 실용위성 1호의 궤도 예측 및 자세 정보, 달의 위치 정보, 태양의 위치 정보를 획득하기 위해서 STK(Satellite ToolKit)를 이용하였으며, 본 연구를 통해 개발된 시뮬레이터에 의해 달 촬영 가능 시간 결정 과정의 효율성은 획기적으로 증대하였다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 1999년도 Proceedings of International Symposium on Remote Sensing
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• pp.331-336
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• 1999

The optical sensors of Electro-Optical Camera (EOC) and Ocean Scanning Multi-spectral Imager (OSMI) aboard the Korea Multi-Purpose SATellite (KOMPSAT) will be placed in a sun synchronous orbit in 1999. The EOC and OSMI sensors are expected to produce the land mapping imagery of Korean territory and the ocean color imagery of world oceans, respectively. Utilization of the EOC and OSMI data would encompass the various fields of science and technology such as land mapping, land use and development, flood monitoring, biological oceanography, fishery, and environmental monitoring. Readiness of data support for user community is thus essential to the success of the KOMPSAT program. As part of testing such readiness prior to the KOMPSAT launch, we have performed the preliminary acceptance test for the KOMPSAT data processing system using the simulated EOC and OSMI data sets. The purpose of this paper is to demonstrate the readiness of the KOMPSAT data processing system, and to help data users understand how the KOMPSAT EOC and OSMI data are processed and archived. Test results demonstrate that all requirements described in the data processing specification have been met, and that the image integrity is maintained for all products. It is however noted that since the product accuracy is limited by the simulated sensor data, any quantitative assessment of image products can not be made until actual KOMPSAT images will be acquired.

• 대한원격탐사학회지
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• 제15권4호
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• pp.357-365
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• 1999

The optical sensors of Electro-Optical Camera (EOC) and Ocean Scanning Multi-spectral Imager (OSMI) aboard the KOrea Multi-Purpose SATellite (KOMPSAT) will be placed in a sun synchronous orbit in late 1999. The EOC and OSMI sensors are expected to produce the land mapping imagery of Korean territory and the ocean color imagery of world oceans, respectively. Utilization of the EOC and OSMI data would encompass the various fields of science and technology such as land mapping, land use and development, flood monitoring, biological oceanography, fishery, and environmental monitoring. Readiness of data support for user community is thus essential to the success of the KOMPSAT program. As a part of testing such readiness prior to the KOMPSAT launch, we have performed the preliminary acceptance test for the KOMPSAT data processing system using the simulated EOC and OSMI data sets. The purpose of this paper is to demonstrate the readiness of the KOMPSAT data processing system, and to help data users understand how the KOMPSAT EOC and OSMI data are processed, archived, and provided. Test results demonstrate that all requirements described in the data processing specification have been met, and that the image integrity is maintained for all products. It is however noted that since the product accuracy is limited by the simulated sensor data, any quantitative assessment of image products can not be made until actual KOMPSAT images will be acquired.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 1999년도 Proceedings of International Symposium on Remote Sensing
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• pp.390-395
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• 1999

Ocean Scanning Multispectral Imager (OSMI) is a payload on the Korean Multi-purpose SATellite (KOMPSAT) to perform worldwide ocean color monitoring for the study of biological oceanography KOMPSAT will be launched in the middle of November this year. The radiometric performance of OSMI is analyzed for various gain settings in the viewpoint of the instrument developer for OSMI calibration and application based on its ground performance measurement data for 8 primary spectral bands of OSMI. The radiometric response linearity and dynamic range are analyzed for the image radiometric calibration and the estimation of OSMI image quality for the ocean remote sensing area. The dynamic range is compared with the nominal input radiance for the ocean and the land. The noise equivalent radiance (NER) corresponding to the instrument radiometric noise is compared with the radiometric resolution of signal digitization (1-count equivalent radiance). The best gain setting of OSMI for ocean monitoring is recommended. This analysis is considered to be useful for the OSMI mission and operation planning, the OSMI image data calibration, and users' understanding about OSMI image quality.

• 대한원격탐사학회지
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• 제15권3호
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• pp.227-238
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• 1999

발사 이전에 OSMI 모의 복사량을 산출함은 실제로 관측할 자료를 추정하고, 자료처리를 위한 준비에 매우 유용하다. 1999년 발사예정인 다목적 실용위성의 탑재체 중의 하나인 OSMI 자료처리 시스템은 SeaWIFS 자료처리 시스템을 OSMI에 맞추어 재개발된 것이다. 모의 복사량 계산은 OSMI 센서의 파장대역 및 스캔방식, 다목적 실용위성의 궤도에 관한 정보가 고려되어야 한다. 본 연구에서는 대양에서의 OSMI 모의 복사량을 산출하기 위해 CZCS에서 관측한 엽록소를 다목적 실용위성이 관측한다는 가정을 하게 되었다. 궤도 예측에는 수정된 Brouwer-Lyddane 모델이, water-leaving 복사량을 산출하기 위해 CZCS 엽록소 농도가, OSMI가 관측할 대기에 의한 복사량 계산에는 여러 가지 복사모델이 이용되었다. OSMI의 412, 443, 490, 555, 765, 865nm 6가시광선 파장대역에서 모의 복사량을 산출하였다. 예상대로, 총 복사량 중 water-leaving 복사량은 아주 작으며 (10% 미만), 태양해면반사에 의한 영향은 태양 적위 근처에서 관측된다. 그러므로 대기보정은 총 복사량으로부터 엽록소 농도를 계산하는데 매우 중요하다. 태양해면반사에 의해 영향을 받는 자료는 사용할 수 없으므로 OSMI 임무 기간내에 지속적인 전구 해양관측을 위해서는 체계적인 자료수집 계획이 요구된다.

• 한국환경과학회지
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• 제14권10호
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• pp.911-917
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• 2005

A comparison between the estimated chlorophyll a from OSMI, the SeaWiFS and the chlorophyll a measured from the research cruises of National Fisheries Research and Development Institute was made. The updated empirical algorithm for calibrating and validating of the estimated chlorophyll a in the East China Sea was formulated by relationship between the estimated chlorophyll a and the field one. The relationship between the chlorophyll a and the band ratio(nLw490/555) was still highest in the OSMI data after launching of KOMPSAT satellite. The distributions of OSMI chlorophyll a were compared with those of sea surface temperature, zooplankton biomass, and catch amounts of the Pacific mackerel in the East China Sea. In case of the relationships in specially winter seasons of 2002 and 2004, the zooplankton and the fish were totally depended on the distributions of SST than those of chlorophyll a.

• 대한원격탐사학회지
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• 제16권2호
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• pp.135-143
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• 2000

Ocean Scanning Multispectral Imager (OSMI) is a payload on the Korean Multi-Purpose SATellite (KOMPSAT) to perform global ocean color monitoring for the study of biological oceanography. HOMPSAT was launched 21 December 1999. The radiometric performance of OSMI is analyzed for various gain settings in the viewpoint of the instrument developer for OSMI calibration and application based on its ground performance data measured before launch. The radiometric response linearity and dynamic range are analyzed and the dynamic range is compared with the nominal input radiance for the ocean and the land. The noise equivalent radiance (NER) corresponding to the instrument radiometric noise is compared with the radiometric resolution of signal digitization (1-count equivalent radiance). The best gain setting of OSMI for ocean monitoring is recommended. This analysis is considered to be useful for the OSMI mission and operation planning, the OSMI image data calibration, and users' understanding about OSMI image quality.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.694-696
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• 2003

The KOMPSAT/OSMI remote sending data of 800 km swath are collected by whisk broom method employing 96 charge coupled devices (CCDs). The stripping noise in the OSMI imageries, which arise mainly due to the non-uniform sensitivities of 96 CCDs, are the major hindrance for oceanographic applications of the OSMI data. The OSMI images are corrected by 'Ensemble Smoothness' method which is based on an assumption that the series of the averages and variances of digital numbers in each line should vary smoothly. The data of each line are corrected by linear regression model of which coefficients are obtained by Ensemble Smoothness method. Our algorithm can be applied not only to OSMI data but also for other remote sensing date collected by whisk broom or push broom.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 1998년도 Proceedings of International Symposium on Remote Sensing
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• pp.43-48
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• 1998

Prior to launch, simulated radiances of the Ocean Scanning Multispectral Imager (OSMI) will be very useful to guess the real imagery of OSMI and to check the data processing system for OSMI. The data processing system for OSMI which is one sensor of Korea Mult i - Purpose Satellite (KOMPSAT) scheduled for launch in 1999 is being developed based on the SeaWiFS Data Analysis System (SeaDAS). Such a simulation should include the spectral bands, orbital and scanning characteristics of the OSMI and KOMPSAT spacecraft. The simulation is also very helpful for finding and preparing for problem areas before launch. This paper describes a method to create simulated radiances of the OSMI over the oceans. Our method for constructing a simulated OSMI imagery is to propagate a KOMPSAT orbit over a field of Coastal Zone Color Scanner (CZCS) pigment values and to use the values and atmospheric components to calculate total radiances. A modified Brouwer - Lyddane model with drag was used for the realistic orbit prediction, the CZCS pigment data were used to compute water - leaving radiances, and a variety of radiative transfer models were used to calculate atmospheric contributions to total radiances detected by OSMI. Imagery of the simulated OSMI total radiances for 6 nominal bands was obtained. As expected, water - leaving radiances were only a small fraction of total radiances and sun glint contaminations were observed near the solar declination. Therefore, atmospheric correction is very important in the calculation of pigment concentration from total radiances. Because the imagery near the sun's glitter pattern is virtually useless and must be discarded, more advanced mission planning will be required.