• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2004년도 한국우주과학회보 제13권2호
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• pp.110-111
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• 2004

• 한국항공우주학회지
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• 제48권10호
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• pp.791-799
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• 2020

2019년 10월 발사된 Northrop Grumman사의 MEV-1(Mission Extenstion Vehicle)은 세계 최초의 무인임무로서 궤도상 유지보수(On-Orbit Servicing)가 실질적으로 가능함을 보였다. 물론 궤도상 유지보수 임무는 수십 년 전부터 제안된 개념으로 운영 중인 위성에 대한 궤도수정 및 유지, 추진제/장비 보급 및 업그레이드, 수리, 궤도상 조립 및 제작, 우주잔해 처리 등 다양한 임무개념으로 발전되고 있으며, 이번 MEV-1 임무의 성공으로 향후 세계적으로 정부기관 및 민간분야 위성사업에서의 시장이 확대될 것으로 예상된다. 궤도상 유지보수 임무는 임무의 특성상 기본적으로 고효율의 전기추진시스템의 활용은 필수적이다. 본 연구에서는 전기추진시스템 중 홀추력기를 활용한 간단한 궤도상 유지보수 임무에 대한 임무해석 내용을 소개하고자 한다. 임무사례로서 정지궤도위성의 수명연장 임무에 대해 다양한 홀추력기 설계변수조합에 대한 설계공간탐색을 수행하고, 설계공간분석 및 최적화를 통해 고려하는 임무에 적합한 홀추력기의 설계 및 운용 파라미터를 제안함과 동시에 임무성능을 도출하였다. 추가적으로 현재 궤도상 유지보수 임무해석 시 개선점과 홀추력기를 활용한 우주임무해석에서의 발전방향을 고찰하였다.

• Journal of Astronomy and Space Sciences
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• 제37권1호
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• pp.51-60
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• 2020

This study designs and analyzes satellite formation flying concepts for the Small scale magNetospheric and Ionospheric Plasma Experiments (SNIPE) mission, that will observe the near-Earth space environment using four nanosats. To meet the requirements to achieve the scientific objectives of the SNIPE mission, three formation flying concepts are analyzed: a cross-shape formation, a square-shape formation, and a cross-track formation. Of the three formation flying scenarios, the cross-track formation scenario is selected as the final scenario for the SNIPE mission. The result of this study suggests a relative orbit control scenario for formation maintenance and reconfiguration, and the initial relative orbits of the four nanosats meeting the formation requirements and thrust limitations of the SNIPE mission. The formation flying scenario is validated by calculating the accumulated total thrust required for the four nanosats. If the cross-track formation scenario presented in this study is applied to the SNIPE mission, it is expected that the mission will be successfully accomplished.

• 천문학회보
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• 제45권1호
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• pp.39.3-40
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• 2020

For the space weather research, KASI (Korea Astronomy and Space Science Institute) is developing the SNIPE (Small-scale magNetospheric and Ionospheric Plasma Experiment) mission, which consists of four 6U CubeSats of ~10 kg. Besides of space weather research, the SNIPE mission has another astrophysical objective, detecting Gamma-Ray Bursts(GRB). By cross-correlating the light curves of the detected GRBs, the fleet shall be able to determine the time difference of the arriving signal between the satellites and thus determine the position of bright short bursts with an accuracy ~100'. To demonstrate the technology of the GRB observation, CSI gamma-ray detectors combined with GPS and IRIDIUM communication modules are placed on each SNIPE CubeSat. The time of each spacecraft is synchronized and when the GRB is detected, the light curve will be transferred to the Mission Operation Center (MOC) by IRIDIUM communication module. By measuring time difference of each GRB signals, the technology for localization of GRB will be proved. If the results show some possibilities, we can challenge the new astrophysical mission for investigating the origin of GRB.

• 천문학회보
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• 제44권2호
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• pp.58.1-58.1
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• 2019

We have developed Ground Software (GSW) of BITSE. The ground software includes mission operation software, data visualization software and data processing software. Mission operation software is implemented using COSMOS. COSMOS is a command and control system providing commanding, scripting and data visualization capabilities for embedded systems. Mission operation software send commands to flight software and control coronagraph. It displays every telemetry packets and provides realtime graphing of telemetry data. Data visualization software is used to display and analyze science image data in real time. It is graphical user interface (GUI) and has various functions such as directory listing, image display, and intensity profile. The data visualization software shows also image information which is FITS header, pixel resolution, and histogram. It helps users to confirm alignment and exposure time during the mission. Data processing software creates 4-channel polarization data from raw data.

• 천문학회보
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• 제46권2호
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• pp.57.2-57.2
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• 2021

An asteroid is important for understanding the condition of our solar system in early-stage because an asteroid, considered as a building block of the solar system, preserves the information when our solar system was formed. It has been continuously flowing into the near-Earth space, and then some asteroids have a probability of impacting Earth. Some asteroids have valuable minerals and volatiles for future resources in space activity. Korean government clarified, in the 3rd promotion plan for space activity, an asteroid sample return mission by the mid-2030s. However, it is almost impossible to do so based on only a single experience of an exploration mission to the Moon, Korea Pathfinder Lunar Orbiter, which will be launched in mid-2022. We propose a Rendezvous Mission to Apophis(RMA), beneficial in terms of science, impact hazardous, resource, and technical readiness for the space exploration of Korea.

• Journal of Astronomy and Space Sciences
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• 제20권3호
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• pp.227-238
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• 2003

Spacecraft mission planning functions including event prediction, mission scheduling, command planning, and ground track display have been developed for the KOMPSAT-2 mission operations. Integrated event prediction functions including satellite orbital events, user requested imaging events, and satellite operational events have been implemented. Mission scheduling functions have been realized to detect the mission conflicts considering the user specified constraints and resources, A conflict free mission scheduling result is mapped into the spacecraft command sequences in the command planning functions. The command sequences are directly linked to the spacecraft operations using eXtensible Markup Language(XML) for command transmission. Ground track display shows the satellite ground trace and mission activities on a digitized world map with zoom capability.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2004년도 한국우주과학회보 제13권2호
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• pp.56-56
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• 2004

• 한국항공우주학회지
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• 제50권12호
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• pp.877-888
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• 2022

최근 루나 게이트웨이의 선구자 임무인 CAPSTONE이 NRHO에서 통신 및 항법 기술 시연을 위해 소형발사체로 발사됨에 따라 전용 소형발사체와 소형위성을 이용하여 심우주 임무를 가능하게 한 이번 행사가 큰 주목을 받았다. 본 연구에서는 소형발사체 이중발사 운영개념이 소개하고, 달, 화성 및 소행성 탐사를 위한 새로운 개념의 가능성을 검토했다. 단독발사로 달 저궤도 임무에 약 247 kg을, 이중발사로 화성 및 소행성 아포피스와 같은 목적지에 각각 215 kg 및 183 kg을 수송할 수 있는 것으로 나타났다.

• International Journal of Aerospace System Engineering
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• 제3권2호
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• pp.31-37
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• 2016

STEP Cube Lab (Cube Laboratory for Space Technology Experimental Project) is a 1U standardized pico-class satellite. Its main mission objective is an on-orbit verification of five fundamental core space technologies. For assuring a successful missions of the STEP Cube Lab with five payloads, electrical power subsystem (EPS) shall sufficiently provide an electrical power to payloads and bus systems of the satellite during an entire mission life. In this study, a design process of EPS system was introduced including power budget analysis considering a mission orbit and various mission modes of the satellite. In conclusion, adequate EPS hardware in compliance with design requirements were selected. The effectiveness and mission capability of EPS architecture design were confirmed through an energy balance analysis (EBA).