基本情報
- 所属
- 国立研究開発法人宇宙航空研究開発機構 宇宙科学研究所 教授
- 学位
- 博士(工学)(1996年3月 名古屋大学)
- 連絡先
- ogawa.hiroyuki
jaxa.jp
- J-GLOBAL ID
- 200901051344540154
- researchmap会員ID
- 1000253790
- 外部リンク
将来の科学衛星に向けた先進的熱制御システムの研究
科学衛星プロジェクトの経験を基に,現状の課題と将来計画を分析し,将来の科学衛星に必要な先進的熱制御システムの研究開発をおこなっています.研究成果はX線天文衛星ひとみに搭載された熱制御システムにフィードバックされている他,次期科学衛星計画への適用が検討されている等,科学衛星の可能性を広げ,世界一流の成果を創出する活動に貢献しています.
科学衛星プロジェクトの熱制御
日欧水星探査計画BepiColombo等のこれまで経験のない極限環境に晒される探査機や,X線大型望遠鏡衛星ひとみ等の熱流体デバイスを積極的に採用した挑戦的プロジェクトにおいては,従来の衛星開発手法やその延長線上では対応できず,これまで経験のない新しい衛星開発手法が求められます.極限環境に耐える新規材料開発や熱設計・解析手法の構築,試験設備整備や検証手法の開発など,新しい研究開発を熱流体力学の学術的知見をもって先導し,熱の観点でプロジェクトの成功に貢献しています.
熱流体力学の応用
熱流体とその周辺の学術的知見を基に,さまざまな宇宙科学プロジェクト活動に貢献しています.再使用ロケットの研究では,エンジン流れや極低温タンク,外部流等熱流体にかかわる課題解決に貢献しています.衛星推進系ではヒドラジンスラスタ内部化学反応流の研究によりスラスタ解析技術の向上に貢献し,ロケット推進系では固体ロケット内部流解析手法を開発し,M-VロケットやSRB-Aの不具合原因究明に貢献しました.その他,ロケットの飛行安全やロケット排気プルームの電波干渉問題等に関わり,ロケット研究に貢献しています.また高速電磁流体中の衝撃波干渉の理論研究や電磁流体を利用した推進システムの研究をおこないました.
経歴
6-
2017年1月 - 現在
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2003年10月 - 2016年12月
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2002年1月 - 2003年9月
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1998年4月 - 2001年12月
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1996年4月 - 1998年3月
学歴
1-
- 1996年3月
委員歴
1-
2013年3月 - 2015年2月
受賞
1-
2015年
論文
95-
Applied Thermal Engineering 264 2025年4月1日A loop heat pipe is a two-phase fluid loop driven by capillary force. Fabrication of a loop heat pipe evaporator by additive manufacturing has been investigated as a low-cost, quick-delivery method for producing a high-performance loop heat pipe. This study investigated the evaporation and heat transfer performance of a wick-integrated evaporator fabricated by additive manufacturing. It is essential to understand the thermal characteristics of the evaporator for a loop heat pipe with an additive-manufactured evaporator for all applications. A tested loop heat pipe with an additive-manufactured evaporator achieved a maximum heat transport capability of 120 W (heat flux: 7.96 W/cm2) and a minimum thermal resistance of 0.321 °C/W in the horizontal orientation at a 20 °C sink temperature. The evaporative heat transfer coefficient and heat leak ratio to the reservoir were calculated for each orientation test result. The maximum evaporative heat transfer coefficient was 50 kW/m2/K and the heat leak ratio was less than 10 % between 10 W and 70 W in the horizontal orientation. These results reveal that the increase in heat leakage to the reservoir due to the decrease in the evaporative heat transfer coefficient leads to the increase in the loop heat pipe operating temperature and thermal resistance. The novelty of this study is that it clarifies the relationship between a loop heat pipe's thermal resistance and evaporator thermal performance by correlating the evaporative heat transfer coefficient and the heat leakage of the wick-integrated evaporator, which uses additive manufacturing, based on the heat transport test results in each orientation.
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International Journal of Thermal Sciences 207 2025年1月A cryogenic capillary pumped loop (CCPL) is a highly efficient two-phase capillary-force-driven heat transport device that operates at cryogenic temperatures. CCPL satisfies the demands for space applications in cryogenic regions as it can transport heat over long distances without mechanical moving parts. In this study, the transient internal flow during the supercritical startup of CCPL was predicted, and various temperature relationships were used to determine whether CCPL starts up or not. The utilized CCPL comprised a wick (pore radius = 1.0 μm), exhibited a heat transport distance of 2 m, and was filled with nitrogen as the working fluid. The supercritical startup experiments were performed at a temperature range of 77–300 K; the startup procedure was initiated when the maximum temperature of CCPL decreased to ∼150 K. Three different liquid supply cycles were tested during the supercritical startup, and the startup time was reduced (a maximum and minimum of 4.1 and 1.9 h, respectively). CCPL started when the evaporator temperature was below the cold reservoir temperature. Thus, the temperature relationship between the cold reservoir and evaporator at the time of applying the heat load to the evaporator could be used to determine the possibility of starting CCPL. The startup was considered successful when the cold reservoir temperature was higher than the evaporator temperature, as the cold reservoir, which exhibited a two-phase state, supplied sufficient liquid to the evaporator, filling the inside of the evaporator with liquid.
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International Journal of Heat and Mass Transfer 231 2024年10月This paper investigated the effect of filling pressure on the operating characteristics of a gravity-assisted cryogenic loop heat pipe(CLHP) for use in gravity environments such as terrestrial and lunar environments. The CLHP wick is made of sintered stainless-steel fibers with a pore radius of 1.56 μm and designed with a heat transport distance of 2.05 m. The experiments were conducted under gravity-assisted conditions (the condenser was placed 0.1 m higher than the evaporator). Notably, the filling pressure originated from the assumed vapor-liquid distribution in the CLHP under steady-state conditions. The filling pressure was varied from 2.9 MPa to 3.4 MPa in 0.1 MPa increments for six different conditions. Specifically, (1) 2.9 MPa and (2) 3.0 MPa are conditions where the heat leakage due to the vapor phase in the evaporator core is large, while (3) 3.1 MPa and (4) 3.2 MPa are conditions where there is no vapor phase in the evaporator core and the surplus vapor phase escapes to the CC. In general, this condition is considered to be the optimum amount of working fluid for room-temperature LHPs when designing. (5) 3.3 MPa and (6) 3.4 MPa are overfilling conditions that cause the CC to be filled with liquid. The results revealed that the higher the filling pressure, the more obvious the variation in operating temperature caused by the transition of drive modes. The maximum heat transfer capability reached 25 W in cases (1)-(4). In cases (5) and (6), the heat transfer capabilities increased to 30 W, although the operating temperature was higher. Furthermore, the hysteresis effect under different filling pressure conditions was newly confirmed. The power cycling experiments demonstrated that hysteresis in the operating temperature occurred at high heat loads and showed a similar trend to the room-temperature LHP.
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Journal of Evolving Space Activities 2 156 2024年7月25日 査読有り
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Applied Thermal Engineering 255 123878-123878 2024年7月One of the main advantages of a cryogenic loop heat pipe (CLHP) is its heat transfer capability over long distances and operability under anti-gravity conditions. However, there are only a few studies on the thermal characteristics of long-distance CLHPs. It is essential to investigate the effect of a hydraulic head on CLHP performance to enhance the utilization of CLHPs in various applications. This study investigated the thermofluidic behaviors of a 2-m nitrogen CLHP with a capillary starter pump (CSP) under horizontal and anti-gravity conditions where the evaporator was 350 mm higher than the condenser. The novelty of the study is to reveal the heat transfer characteristics and operating mechanisms under anti-gravity conditions based on comparisons with experimental results under horizontal conditions. In the CLHP, a fine stainless-steel porous wick with a pore radius of 1.0 μm and permeability of 1.3 × 10−13 m2 was used for an evaporator and the CSP. The lengths of the vapor line, condenser, and liquid line were 2000, 1500, and 2000 mm, respectively. When a heat load of 4 W was applied to the CSP and evaporator, the CLHP successfully started with an initial cooling condition called a supercritical startup under anti-gravity conditions. The startup temperature behaviors were compared under horizontal and anti-gravity conditions. The thermal resistance of the CLHP with a stepped-up evaporator heat load and various CSP heat loads was evaluated for two CLHP orientations. The CLHP stably operated under evaporator heat loads of 4–24 W (horizontal) and 4–20 W (anti-gravity) for three CSP heat loads of 0, 2, and 4 W. The effect of the CLHP orientation on the thermal resistance with various CSP heat loads is discussed. This study enhances the applicability of the long-distance CLHP to various applications with a high degree of postural freedom by revealing the operating mechanism and thermal characteristics of the long-distance CLHP under anti-gravity and horizontal conditions.
MISC
382-
International Journal of Energetic Materials and Chemical Propulsion 9(3) 219-231 2010年
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61st International Astronautical Congress 2010, IAC 2010 6 5076-5093 2010年ISAS activities for reusable rocket technology and architecture including flight demonstration by the RVT (Reusable Vehicle Testing) have shown various progresses in technical areas such as frequent-flight propulsion systems, reusable rocket engines, returning flight and vertical landing techniques and demonstrations, composite cryogenic LH2 tank studies, new architectures for reusable and repeated flights with quick turnaround and so on. Following these basic studies of reusable rocket, mission definition and system requirement synthesis of the reusable sounding rocket are completed. In addition to the technical and performance related issues, its operational aspects and requirements for the frequent and repeated flight were given stressed. Throughout the studies, technical readiness to the reusable rocket technique and for the system synthesis for the reusable sounding rocket vehicle are in progress. For the sounding rocket's system definition and requirement analysis, research of the flight demand such as the number-of-flight per year and its frequency by the potential user communities. These requirements are from the needs of the middle to upper atmosphere research, studies from micro-gravity community, engineering community which may use this repeated flight opportunity. Copyright ©2010 by the International Astronautical Federation. All rights reserved.
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日本伝熱シンポジウム講演論文集(CD-ROM) 47th 120-120 2010年自励振動ヒートパイプにリザーバをつけることにより,可変コンダクタンスヒートパイプとして用いることができることが知られている.リザーバを一定温度にした状態で,蒸発部への熱入力や放熱面の環境を変化させると,蒸発部温度がリザーバ温度になるように熱輸送が自律的に制御される.この実験について報告する.
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日本伝熱シンポジウム講演論文集(CD-ROM) 47th 239-239 2010年ループヒートパイプ(LHP)は,その熱輸送性能や搭載性が利点となる熱制御デバイスである.本実験ではミッション機器への応用も視野に入れて小型LHPに着目し,その動作特性を解明するためPTFE多孔質を用いた100W級の小型LHPを製作した.そして,熱負荷に対する動作温度の関係など基本性能を取得した.また,熱電変換素子によりリザーバの温度制御を行い,LHP動作温度の制御特性について実験を行い,リザーバ制御の有用性について実験的に示すことができた.
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日本伝熱シンポジウム講演論文集(CD-ROM) 47th 241-241 2010年非凝縮ガスを使用した可変コンダクタンスヒートパイプ(VCHP)の研究を行った. VCHPは従来のヒートパイプにリザーバをつけたもので,ヒートパイプ部は軸方向グルーブを持つアルミニウム製である.リザーバにはステンレス製フェルトを入れ,ヒートパイプ部のグルーブとつないだ.作動流体にはアセトン,非凝縮ガスは空気を使用した.リザーバ温度が一定のとき,熱負荷を変化させても,断熱部の温度が一定に保たれVCHPとして正常に動作しているのが確認できた.また,蒸発部の温度を検知して,リザーバに付けたヒータをPID制御することで,蒸発部の温度を一定にすることができた.
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日本伝熱シンポジウム講演論文集(CD-ROM) 47th 27-27 2010年木星以遠の外惑星では太陽光の減衰が激しいため,深宇宙探査機にはラジオアイソトープ(RI)発電が有用である.RI発電は,RIの崩壊熱を電気エネルギーに変換して一次電池として使用するものであり,米国及びロシアでは1960年代から宇宙用電源として用いられてきた,実績ある電源である.その熱電変換器として最も多用されているのが熱電変換素子であり,これを用いたRI発電をRTGと呼ぶ.日本では,民生用の熱電変換素子の開発は行われてきたが,RTGへの利用は検討例すらない.宇宙用と民生用では使用する熱環境条件が大きく異なる.本件では,RIの代用として擬似熱源を使用し,宇宙環境を模擬した条件での熱電変換素子の性能評価を行う.
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福井工業大学研究紀要(CD-ROM) (39) 328-335 2009年Spacecraft for future scientific missions demand evolutional thermal control technologies with small resources of power and weight. An accurate temperature control technology of light weight is especially important. We proposed VC-OHP (Variable Conductance Oscillating Heat Pipe) as a candidate for such a requirement. VC-OHP is a new concept of a temperature control device, which consists of an oscillating heat pipe and a reservoir. The thermal conductance of the heat pipe can be varied with assist of the reservoir and the heating section temperature can be controlled. This paper describes the analytical study on temperature control mechanism of VC-OHP.
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日本伝熱シンポジウム講演論文集 2009 348-348 2009年民生および宇宙分野で省エネで高効率な熱輸送技術が強く求められている。本研究では、ウィックとよばれる多孔質材内で発生する毛細管力を利用したループヒートパイプ技術に着目し、その高性能化と実用化に向けた研究開発に取り組んでいる。本報告では作動流体のチャージ量変化に伴う熱特性変化を実験的に明らかにしたので報告する。
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日本伝熱シンポジウム講演論文集 2009 351-351 2009年海外において次世代のスタンダードな熱制御技術として毛細管駆動型二相流体ループ(ループヒートパイプ)の研究開発が進められており、本研究では日本の将来の宇宙ミッションを見据え,100W級の小型ループヒートパイプに着目し研究を行っている。今回、ループヒートパイプのリザーバ/補償チャンバー(Compensation Chamber, CC)の温度制御に熱電交換モジュールを用いて、ループヒートパイプの動作特性について実験および評価を行ったので報告する。
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日本伝熱シンポジウム講演論文集 2009 356-356 2009年近年、惑星探査や月面着陸などミッションの高度化にともない、より高性能で複雑な熱制御技術が必要とされている。特に、熱環境が複雑に変動するミッションにおいて、衛星の熱設計を高温側および低温側で同時に満足できるような熱制御技術が重要である。そこで、アメリカをはじめ海外では次世代のスタンダードな熱制御技術として毛細管駆動型二相流体ループ(ループヒートパイプ:LHP)が開発されてきた。本研究では日本の将来の宇宙ミッションを見据え、100W級の小型LHPに着目し、これまでにその起動特性ならびに熱輸送特性の評価を行ってきた。今回は、このループヒートパイプの重力方向に対する実験および評価を行ったので報告する。
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日本伝熱シンポジウム講演論文集 2009 82-82 2009年自励振動型ヒートパイプ(OHP)にリザーバをつけ,リザーバの温度制御を行うことによって,加熱部の温度を一定の状態に保ったまま異なる大きさの熱量を輸送するなどの温度制御が可能になる.本研究では,リザーバ付きOHPの地上試験結果について報告する.
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PROCEEDINGS OF THE 19TH ESA SYMPOSIUM ON EUROPEAN ROCKET AND BALLOON PROGRAMMES AND RELATED RESEARCH 671 249-254 2009年A fully reusable sounding rocket is proposed in ISAS/JAXA. Vehicle systems and ground/flight operations are designed for observations of atmospheric phenomena, micro-gravity experiments and so on. In the present design of the reusable sounding rocket, the vehicle carries a 100kg payload up to 120km altitude. The turnaround time for one flight is less than 24 hours (1 day). In the typical ballistic-flight up to 120km, the total flight time is about 600sec. Maximum Mach number is about 4, and the flight condition of Mach number below 1.0 (subsonic speed) is kept for about 70sec over 110km altitude. In this subsonic flight, the observed atmosphere around the vehicle is not affected by the shock wave. This is desirable for the atmospheric observation. Maximum acceleration in the flight is about 4G in ascent and 7G in descent. For the micro-gravity experiments, the flight environments of acceleration less than 10(-3)G, 10(-4)G and 10(-5)G is able to be made for about 180, 150 and 120sec, respectively.
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International Astronautical Federation - 59th International Astronautical Congress 2008, IAC 2008 9 6014-6019 2008年Tethered-Solar Power Satellite (Tethered-SPS) consists of power generation/transmission panels suspended by tether wires. The most important feature of the Tethered-SPS is that it is constructed by perfectly equivalent power generation/transmission units. Each unit panel, 100 m × 95 m, is suspended by four 5 km-tether wires deployed from a bus unit. The weight and output power of the unit SPS are 42.5 MT and 2.1 MW, respectively. The engineering studies have been conducted to design the power generation/ transmission panel and to show how to deploy the panel. In addition to the engineering research, two major environmental issues, the effect of hyper-velocity impact of the debris or meteoroids and the interaction of the solar cell array with the ambient plasma, have been studied. The engineering studies have shown that the power generation/transmission panel is technically feasible using the near-term technologies. The environmental studies have shown preliminary guidelines to design the power generation/transmission panel.
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宇宙航空研究開発機構特別資料: 宇宙航空研究開発機構 情報・計算工学センター 衛星環境プラズマ数値シミュレーションワークショップ報告書 = JAXA Special Publication: JAXA/JEDI Workshop on Numerical Plasma Simulation for Spacecraft Environment JAXA-SP-06-014(6) 111-121 2007年2月1日資料番号: AA0063157009レポート番号: JAXA-SP-06-014
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PROCEEDINGS OF THE ASME/JSME THERMAL ENGINEERING SUMMER HEAT TRANSFER CONFERENCE 2007, VOL 3 721-726 2007年The Loop Heat Pipes (LHPs) are robust, self-starting and a passive two-phase thermal control system that uses the latent heat of vaporization of an internal working fluid to transfer heat from an evaporator (the heat source) to a condenser (the heat sink). The circulation of the working fluid is accomplished by capillary pressure gradients in a fine porous wick with very small pores. LHPs are rapidly gaining acceptance in the aerospace community and several terrestrial applications are emerging as well.In the present study, a miniature LHP is investigated the thermal performance for spacecraft thermal control system. Tests will be conducted including start-up, low power, power ramp up, high power, rapid power change, and rapid sink temperature change. Finally, we want to demonstrate the potential of LHP to become the next-generation heat transfer device to cool terrestrial devices such as advanced electronic which have high power dissipations.First of all, this paper presents the influence of the gravitational forces on the LHP performance. The present tests performed under steady state condition with three different orientations (horizontal, gravity-assisted, anti-gravity).
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熱工学コンファレンス講演論文集 2007 381-382 2007年This paper presents an experimental study to investigate the effectiveness of using a thermoelectric converter to control the loop heat pipe operating temperature. The compensation chamber (CC) was controlled at the set point temperature by cooling and heating the TEC module, of which one side is attached to the CC and the other side is connected to the evaporator through a thermal strap. The test results show that the TEC can control the operating temperature to the set point temperature. The power saving by using the TEC was also demonstrated.
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18TH ESA SYMPOSIUM ON EUROPEAN ROCKET AND BALLOON PROGRAMMES AND RELATED RESEARCH 647 187-192 2007年A fully reusable rocket vehicle is proposed as a sounding rocket for observations of atmospheric phenomena, micro-gravity experiments and so on. Vehicle systems and ground / flight operations are designed for such science observations. For the development of the reusable rocket, a small test vehicle was built and flight-tested. This Reusable Vehicle Testing (RVT) lessons campaign provide repeated experiences of turnaround operations and vertical take-off and landing flights. In the present design of the reusable sounding rocket, the total length and maximum diameter of the vehicle is about 10m and 3m, respectively. The vehicle is propelled by the propulsion system composed of four liquid hydrogen / liquid oxygen engines. The weight of a payload carried to 120 km altitude is 100kg in the nose-fairing. The instrument for observations can be reused because of the repeated flight. The turnaround time for one flight is less than 24 hours (1 day). In the typical ballistic flight up to 120 km, the flight environments under 10(-5)G acceleration is able to be made for about 120 sec. The flight Mach number can be subsonic around the summit in the trajectory. These properties of reusable sounding rocket are expected to be useful and effective for many science missions.
書籍等出版物
1講演・口頭発表等
33-
46th International Conference on Environmental Systems 2016年7月
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第16回宇宙科学シンポジウム 講演集 = Proceedings of the 16th Space Science Symposium 2016年1月 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS)第16回宇宙科学シンポジウム (2016年1月6日-7日. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS)相模原キャンパス), 相模原市, 神奈川県資料番号: SA6000046247レポート番号: S4-010
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45th International Conference on Environmental Systems 2015年7月
所属学協会
5-
2020年9月
共同研究・競争的資金等の研究課題
10-
日本学術振興会 科学研究費助成事業 2023年4月 - 2027年3月
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日本学術振興会 科学研究費助成事業 2024年4月 - 2026年3月
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日本学術振興会 科学研究費助成事業 2023年4月 - 2026年3月
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日本学術振興会 科学研究費助成事業 基盤研究(B) 2018年4月 - 2021年3月
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日本学術振興会 科学研究費助成事業 挑戦的萌芽研究 2016年4月 - 2018年3月
産業財産権
6学術貢献活動
1-
パネル司会・セッションチェア等, 査読2003年7月 - 現在
● 指導学生等の数
6-
年度2018年度(FY2018)博士課程学生数1
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年度2019年度(FY2019)博士課程学生数2修士課程学生数1学術特別研究員数1
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年度2020年度(FY2020)博士課程学生数1修士課程学生数1学術特別研究員数1
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年度2018年度(FY2018)博士課程学生数1
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年度2019年度(FY2019)博士課程学生数2修士課程学生数1学術特別研究員数1
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年度2020年度(FY2020)博士課程学生数1修士課程学生数1学術特別研究員数1
● 専任大学名
2-
専任大学名東京大学(University of Tokyo)
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専任大学名東京大学(University of Tokyo)
● 所属する所内委員会
6-
所内委員会名研究所会議
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所内委員会名プログラム会議
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所内委員会名信頼性品質会議
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所内委員会名環境・安全管理統括委員会
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所内委員会名ISASニュース編集小委員会
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所内委員会名宇宙科学プログラム技術委員会