• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.12
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• pp.1116-1123
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• 2015

The lifetime of a geostationary satellite depends on the residual propellant amount and therefore the precise residual propellant gauging is very important for the mitigation of economic loss arised from premature removal of satellite from its orbit, satellites replacement planning, slot management and so on. In this paper, the thermal mass method and its uncertainty are described. The residual propellant analysis of a geostationary satellite is simulated based on the KOREASAT data and the uncertainty of thermal mass method is calculated by using the Monte Carlo method. The results of this study show the importance parameter of estimation residual propellant using the thermal mass method.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• v.y2005m4
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• pp.5-10
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• 2005

The geostationary satellite propulsion system has thermistors which can measure liquid propellant temperature at tanks, pipes and etc. In the satellite propulsion system with several tanks, the propellant in the tanks is moved by temperature change and this temperature pattern is constant. In this paper, the temperature change pattern of KOREASAT 1 propulsion system is compared and the prediction study of pressurant inflow using temperature change of geostationary satellite propulsion system is described.

• 한국전산유체공학회:학술대회논문집
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• 2009.04a
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• pp.142-147
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• 2009

COMS (Communication, Ocean and Meteorological Satellite) is a geostationary satellite and has been developing by KARI for communication, ocean and meteorological observations. It will be tested under vacuum condition and very low temperature in order to verify thermal design of COMS. The test will be performed by using KARI large thermal vacuum chamber, which was developed by KARI, and the COMS will be the first flight satellite tested in this chamber. The purposes of thermal balance test are to correlate analytical model used for design evaluation and predicting temperatures, and to verify and adjust thermal control concept. KARI has plan to use heating plates to simulate space hot condition especially for radiator panels such as north and south panels. They will be controlled from 90K to 273K by circulating GN2 and LN2 alternatively according to the test phases, while the shroud of the vacuum chamber will be under constant temperature, 90K, during all thermal balance test. This paper presents thermal modelling including test chamber, heating plates and the satellite without solar array wing and Ka-band reflectors and discusses temperature prediction during thermal balance test.

• Journal of the Korean earth science society
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• v.39 no.4
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• pp.305-316
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• 2018

Satellite-derived sea surface winds (SSWs) and atmospheric motion vectors (AMVs) over the global ocean, particularly including the areas in and around tropical cyclones (TCs), have been provided in a real-time and continuous manner. More and better information is now derived from technologically improved multiple satellite missions and wind retrieving techniques. The status and prospects of key SSW products retrieved from scatterometers, passive microwave radiometers, synthetic aperture radar, and altimeters as well as AMVs derived by tracking features from multiple geostationary satellites are reviewed here. The quality and error characteristics, limitations, and challenges of satellite wind observations described in the literature, which need to be carefully considered to apply the observations for both operational and scientific uses, i.e., assimilation in numerical weather forecasting, are also described. Additionally, on-going efforts toward merging them, particularly for monitoring three-dimensional TC wind fields in a real-time and continuous manner and for providing global profiles of high-quality wind observations with the new mission are introduced. Future research is recommended to develop plans for providing more and better SSW and AMV products in a real-time and continuous manner from existing and new missions.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.645-648
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• 2005

The COMS(Communication, Ocean and Meteorological Satellite), a multi-mission geo-stationary satellite, is being developed by KARl. The first mission of the COMS is the meteorological image and data gathering for weather forecast by using a five channel meteorological imager. The second mission is the oceanographic image and data gathering for marine environment monitoring around Korean Peninsula by using an eight channel Geostationary Ocean Color Imager(GOCI). The third mission is newly developed Ka-Band communication payload certification test in space by providing communication service in Korean Peninsula and Manjurian area. There were many low Earth orbit satellites for ocean monitoring. However, there has never been any geostationary satellite for ocean monitoring. The COMS is going to be the first satellite for ocean monitoring mission on the geo-stationary orbit. The meteorological image and data obtained by the COMS will be distributed to end users in Asia-Pacific area and it will contribute to the improved weather forecast.

• Journal of Korea Society of Industrial Information Systems
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• v.19 no.1
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• pp.31-41
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• 2014

The satellite on geostationary orbit accommodates multiple payloads into a single spacecraft platform and launched in June 26, 2010. The Electrical Power Subsystem provides a fully regulated power bus at $50V_{DC}$ in sunlight and eclipse conditions. The electrical power required to the satellite is generated by a solar array wing and the energy is stored by a Li-Ion battery with a capacity of 192.5Ah. This paper selects the main design parameters, compares and analyzes with the results at ground test and in orbit operation to apply this performance evaluation of the Electrical Power Subsystem to next satellite design on geostationary orbit. The Electrical Power Subsystem is demonstrated nominal behavior without significant degradation through the performance evaluation from design to in orbit operation.

• Journal of Korean Society for Atmospheric Environment
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• v.29 no.2
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• pp.199-210
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• 2013

Detailed 3 dimensional structure of Asian dust plume has been analyzed from the retrieved aerosol data from two different satellites which are the Korea's $1^{st}$ geostationary satellite, namely the Communication, Ocean, Meteorological Satellite (COMS) spacecraft launched in 2010, and the NASA's Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO). COMS spacecraft provides the first time resolved aerial aerosol maps by the systematically well-calibrated multispectral measurements from the Geostationary Ocean Color Imager (GOCI) instrument. GOCI data are used here to evaluate intensity, spatial distribution, and long-range transport of Asian dust plume during 1~2 May 2011. We found that the strong Asian dust plume showing AOT of 2~5 was lofted to the altitude around 2~4 km above the Earth's surface and transported over Yellow Sea with a speed of about 25 km/hr. The CALIPSO extinction coefficient and particulate depolarization ratio (PDR) profiles confirmed that nonspherical dust particles were enriched in the dust plume. This study is a first example of quantitative integration of GOCI and CALIOP measurements for clarifying the overall structure of an Asian dust event.

• Journal of Satellite, Information and Communications
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• v.11 no.4
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• pp.89-93
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• 2016

In this paper, we provide a summary on the core essence of INR (Image Navigation and Registration) System technology which is an essential function of geostationary remote sensing satellites. Its origin and evolution history is reviewed, its core elements and governing concept for each element are described, and a generic INR architecture is suggested which can cover all seemingly conceivable INR systems of the past, the current and the future. By this, we intend to identify and illuminate the core technical contents and the key aspects in the foreseen prospect of the up-coming INR systems and the related technologies.

• Journal of the Korean Society of Propulsion Engineers
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• v.21 no.2
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• pp.60-71
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• 2017

A trajectory analysis program is developed using a 3DOF trajectory model for the performance analysis of geostationary launch vehicles by system options. Launch trajectory and the performance of injection at GTO was estimated using this program for several propellant options, engine types, number of engines and the location of launch site. Results of the analysis presents that the possibility of mission accomplishment by several design options using domestic launch sites and the development direction of GEO launch vehicles.

• 한국전산유체공학회:학술대회논문집
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• 2010.05a
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• pp.416-421
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• 2010

The north and south panel of a geostationary satellite are used for radiator panels to reject internal heat dissipation of electronics units and utilize several heat pipe networks to control the temperatures of units and the satellite within proper ranges. The design of these panels is very important and essential at the conceptual design and preliminary design stage so several thousands of nodes of more are utilized in order to perform thermal analysis of panel. Generating a large number of nodes(meshes) of the panel takes time and is tedious work because the mesh can be easily changed and updated by locations of units and heat pipes. Also the detailed panel model can not be integrated into spacecraft thermal model due to its node size and limitation of commercial satellite thermal analysis program. Thus development of a program was required in order to generate detailed panel model, to perform thermal analysis and to make a reduced panel model for the integration to the satellite thermal model. This paper describes the development and the verification of panel thermal analysis program with ist main modules and its main functions.