• Journal of Astronomy and Space Sciences
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• v.26 no.1
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• pp.111-126
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• 2009

We used an optical observation system with a 0.6m wide-field telescope and 5 computers system in KASI (Korean Astronomy and Space Science Institute) for satellite optical observation. Optical data have errors that are caused by targeting, expose start time and end-point determination. Gauss method for initial orbit determination was tested using angle-only data simulated by KODAS. And suitable time span is confirmed for result which has minimum errors. Initial orbit determination results are proved that optical observation system in KASI is possible satellite tracking for a short period. And also through differential correction, initial orbit determination results are improved.

• Journal of Satellite, Information and Communications
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• v.12 no.3
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• pp.1-7
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• 2017

Climate change adaptation must be prepared, because the pattern of climate change in Korea is higher than the global average. In particular, it is estimated that Korea's economic loss due to climate change will reach 2,800 trillion won, and at least 300 trillion won will be needed for adaptation to climate change(KEI, 2011). Accurate climate change forecasts and impact forecasts are essential for efficient use of enormous climate change adaptation costs. For this climate change prediction and impact analysis, it is necessary to grasp not only the global average concentration but also the inhomogeneity of the greenhouse gas concentration which appears in each region. In this study, we analyze the feasibility of developing a greenhouse gas observation satellite, which is a cause of climate change, and present a development plan for a low orbit environmental satellite by examining the current status of the operation of the greenhouse gas observation satellite. The GHG monitoring satellite is expected to expand the scope of environmental monitoring by water/soil/ecology in addition to climate change, along with weather/agriculture/soil observation satellites.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.162-164
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• 2003

The multi-disciplinary research project Strengthening Local Authorities in Risk Management (SLARIM), initiated by ITC, includes three case study cities in Asia. An important question is: what are the essential data for risk management and how to access such data. The role of common sources (e.g. census data), data derived from remote sensing (high-resolution satellite imagery, aerial photos), and data from close sensing (field observation, including mobile GIS) to acquire essential risk management data will be discussed. Special attention is given to the question of the minimum area and to disaggregating population data. A few examples are given of Kathmandu / Lalitpur, Nepal.

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.1
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• pp.62-77
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• 2019

Open Data Cube(ODC) has been emerging and developing as the open source platform in the Committee on Earth Observation Satellites(CEOS) for the Global Earth Observation System of Systems(GEOSS) deployed by the Group on Earth Observations (GEO), ODC can be applied to the deployment of scalable and large amounts of free and open satellite images in a cloud computing environment, and ODC-based country or regional application services have been provided for public users on the high performance. This study first summarizes the status of ODC, and then presents concepts and some considering points for linking this platform with Korea Multi-Purpose Satellite (KOMPSAT) images. For the reference, the main contents of ODC with the Google Earth Engine(GEE) were compared. Application procedures of KOMPSAT satellite image to implement ODC service were explained, and an intermediate process related to data ingestion using actual data was demonstrated. As well, it suggested some practical schemes to utilize KOMPSAT satellite images for the ODC application service from the perspective of open data licensing. Policy and technical products for KOMPSAT images to ODC are expected to provide important references for GEOSS in GEO to apply new satellite images of other countries and organizations in the future.

• Journal of Positioning, Navigation, and Timing
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• v.13 no.2
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• pp.199-206
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• 2024

The GEO-KOMPSAT-2A (GK2A) satellite, which was launched in December 2018, carries weather observation payloads and uses the image navigation and registration system to calibrate the observation images. The calibration system requires accurate orbit prediction data and depends on the accuracy of the orbit determination accuracy. In order to find a possible way to improve the current orbit determination accuracy of the GK2A flight dynamic subsystem module, orbit determination software was developed to independently evaluate the orbit determination accuracy. A comprehensive satellite dynamic model is applied for a batch-type least squares filter. When determining the orbit, thrust firing during station-keeping maneuvers and wheel-off loading maneuvers is taken into account. One month of GK2A ranging data were processed to estimate the satellite position on a daily basis. The orbit determination error was evaluated by comparing estimates during overlapping estimation intervals.

• Journal of the Korean earth science society
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• v.41 no.4
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• pp.323-343
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• 2020

Observation data measured at Ieodo Ocean Research Station (IORS) have been utilized in oceanographic and atmospheric studies since 2003. Sea level data observed at the IORS have not been paid attention as compared with many other variables such as aerosol, radiation, turbulent flux, wind, wave, fog, temperature, and salinity. Total sea level rises at the IORS (5.6 mm yr^-1) from both satellite and tide-gauge observations were higher than those in the northeast Asian marginal seas (5.4 mm yr^-1) and the world (4.6 mm yr^-1) from satellite observation from 2009 to 2018. The rates of thermosteric, halosteric, and steric sea level rises were 2.7-4.8, -0.7-2.6, 2.3-7.4 mm yr^-1 from four different calculating methods using observations. The rising rate of the steric sea level was higher than that of the total sea level in the case with additional data quality control. Calculating the non-steric sea level was not found to yield meaningful results, despite the ability to calculate non-steric sea level by simply subtracting the steric sea level from total sea level. This uncertainty did not arise from the data analysis but from a lack of good data, even though tide, temperature, and salinity data were quality controlled two times by Korea Hydrographic and Oceanography Agency. The status of the IORS data suggests that the maintenance management of observation systems, equipment, and data quality control should be improved to facilitate data use from the IORS.

• Proceedings of the KSRS Conference
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• v.2
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• pp.791-793
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• 2006

In the satellite camera, the incoming light source is converted to electronic analog signals by the electronic component for example CCD (Charge Coupled Device) detectors. The analog signals are amplified, biased and converted into digital signals (pixel data stream) in the video processor (A/Ds). The outputs of the A/Ds are digitally multiplexed and driven out using differential line drivers (two pairs of wires) for cross strap requirement. The MSC (Multi-Spectral Camera) in the KOMPSAT-2 which is a LEO spacecraft will be used to generate observation imagery data in two main channels. The MSC is to obtain data for high-resolution images by converting incoming light from the earth into digital stream of pixel data. The video data outputs are then MUXd, converted to 8 bit bytes, serialized and transmitted to the NUC (Non-Uniformity Correction) module by the Hotlink data transmitter. In this paper, the video data streams, the video data format, and the image data processing routine for satellite camera are described in terms of satellite camera control hardware. The advanced satellite with very high resolution requires faster and more complex image data chain than this algorithm. So, the effective change of the used image data chain and the fast video data transmission method are discussed in this paper

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.212-215
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• 2004

GOES-9 has been operated with the status of the Image Motion Compensation(IMC) off since last October. As the IMC function turned off, the sub-satellite point(SSP) of GVAR data was changed with the effect of the satellite motions. This makes the image registration, to maintain pixels within an image and between successive images to their earth-referenced information, not to be possible any more. In the paper, we introduce the method to accomplish image registration and the result of the SSP observation with the status of IMC off.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.194.2-194.2
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• 2012

Korea Aerospace Research Institute has developed an earth observation satellite and it was launched into its orbit in 2012 by using a foreign commercial launch vehicle. The launch site authority has imposed safety requirements to the spacecraft developer to ensure the safety of the personnel and to protect launch vehicle, spacecraft and facilities from accidents associated with the satellite operation at the launch site. This paper describes the range safety activities implemented for the satellite and supporting equipments during the whole phase of their design, manufacturing/test and operation at the launch site. To ensure the integrated requirements for safety management and design, system safety program plan has been developed. And based upon the plan, spacecraft developer conducted hazard analysis to identify and establish safety requirements to reflect in designs, procedures, operations. The result of the hazard analysis has been complied into safety data packages and it was reviewed by launch site review board at the safety reviews and finally it was approved to launch.

• Journal of Astronomy and Space Sciences
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• v.28 no.4
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• pp.333-344
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• 2011

An optical tracking system has advantages for observing geostationary earth orbit (GEO) satellites relatively over other types of observation system. Regular surveying for unidentified space objects with the optical tracking system can be an early warning tool for the safety of five Korean active GEO satellites. Two strategies of positioning on the observed image of Communication, Ocean and Meteorological Satellite 1 are tested and compared. Photometric method has a half root mean square error against streak method. Also eccentricity method for initial orbit determination (IOD) is tested with simulation data and real observation data. Under 10 minutes observation time interval, eccentricity method shows relatively better IOD results than the other time interval. For follow-up observation of unidentified space objects, at least two consecutive observations are needed in 5 minutes to determine orbit for geosynchronous orbit space objects.