Kyushu University Academic Staff Educational and Research Activities Database
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Takumi Onchi Last modified date:2020.07.01

Graduate School

 Reseacher Profiling Tool Kyushu University Pure
Advanced Fusion Research Center .
Academic Degree
Country of degree conferring institution (Overseas)
Field of Specialization
Plasma Engineering
Total Priod of education and research career in the foreign country
Research Interests
  • Electron cyclotron heating/current-drive on QUEST spherical tokamak
    keyword : Plasma, Spherical tokamak, RF plasma heating/current-drive
  • Power electronics for Tokamak Ohmic heating
    keyword : High voltage power supply, power electronics, Tokamak
  • Permutation entropy and statistical complexity of time series data in plasma experiment
    keyword : Permutation entropy, statistical complexity
Academic Activities
1. Evaluation of Time-Series Data Using Permutation Entropy and Statistical Complexity.
1. Takumi Onchi, Hiroshi Idei, K. Nakamura, T. Nagata, S. Kawasaki, R. Ashida, M. Fukuyama, Makoto Hasegawa, Ryuya Ikezoe, A. Higashijima, K. Kuroda, Yoshihiko Nagashima, Kazuaki Hanada, High voltage electrical system of 8.56 GHz CW klystron for electron cyclotron heating on QUEST spherical tokamak, Fusion Engineering and Design, 10.1016/j.fusengdes.2019.04.043, 146, 2567-2570, 2019.09.
2. T. Onchi, A. Fujisawa, A. Sanpei, H. Himura, S. Masamune, and RELAX team, Permutation entropy and statistical complexity in characterising low-aspect-ratio reversed-field pinch plasma, Physica Scripta,, 92, 5, 055601, 2017.04.
3. T. Onchi, H. Zushi, K. Mishra, Y. Oyama, Y. Nagashima, K. Hanada, H. Idei, M. Hasegawa, A. Kuzmin, H. Miura, K. Nakamura, A. Fujisawa, K. Nagaoka, Response of the far scrape-off layer plasma to strong gas puffing in the high poloidal beta configuration of the QUEST spherical tokamak, PLASMA PHYSICS AND CONTROLLED FUSION, 10.1088/0741-3335/58/11/115004, 58, 11, 2016.11.
4. Takumi Onchi, D. McColl, A. Rohollahi, C. Xiao, A. Hirose, M. Dreval, S. Wolfe, Development Toward a Repetitive Compact Torus Injector, IEEE Transactions on Plasma Science, 44, 2, 195, 2016.02.
5. T. Onchi, Y. Mahira, K. Nagaoka, S. Tashima, S. Banerjee, K. Mishra, H. Idei, K. Hanada, K. Nakamura, A. Fujisawa, Y. Nagashima, M. Hasegawa, K. Matsuoka, A. Kuzmin, O. Watanabe, S. Kawasaki, H. Nakashima, A. Higashijima, Observation of heat flux and plasma flow in scrape off layer in QUEST, Journal of Nuclear Materials, 463, 428, 2015.08.
6. T. Onchi, H. Zushi, K. Mishra, Y. Mahira, K. Nagaoka, K. Hanada, H. Idei, M. Hasegawa, K. Nakamura, A. Fujisawa, Y. Nagashima, K. Matsuoka, S. Tashima, S. Banerjee, A. Kuzmin, S. Kawasaki, H. Nakashima, A. Higashijima, O. Watanabe, Heat flux and plasma flow in the far scrape-off layer of the inboard poloidal field null configuration in QUEST, Physics of Plasmas, 22, 8, 082513, 2015.08.
7. T. Onchi, A. Fujisawa, A. Sanpei, A prototype diagnostics system to detect ultraviolet emission for plasma turbulence, Review of Scientific Instruments, 85, 11, 113502, 2014.11.
8. T. Onchi, D. McColl, M. Dreval, S. Wolfe, C. Xiao, A. Hirose, Design and implementation of fast charging circuit for repetitive compact torus injector, Fusion Engineering and Design, 89, 11, 2559, 2014.11.
9. T. Onchi, Y. Liu, M. Dreval, D. McColl, S. Elgriw, D. Liu, T. Asai, C. Xiao, A. Hirose, Effects of compact torus injection on toroidal flow in the STOR-M tokamak, Plasma Physics and Controlled Fusion, 55, 3, 035003, 2013.03.
10. T. Onchi, Y. Liu, M. Dreval, D. McColl, T. Asai, S. Wolfe, C. Xiao and A. Hirose, Fuelling Effect of Tangential Compact toroid injection in STOR-M Tokamak, CNS(Canadian Nuclear Society)2012 conference paper, 137, 2012.06.
11. T. Onchi, R. Ikezoe, K. Oki, A. Sanpei, H. Himura, S. Masamune, N. Nishino, H. Koguchi, Observation of Helical Structure by Imaging Diagnostics in a Low-Aspect-Ratio Reversed Field Pinch, Journal of the Physical Society of Japan, 80, 11, 114501, 2011.10.
12. T. Onchi, R. Ikezoe, K. Oki, A. Sanpei, H. Himura, S. Masamune, Tangential soft-x ray imaging for three-dimensional structural studies in a reversed field pinch, Review of Scientific Instruments, 81, 7, 073502, 2010.07.
13. Takumi Onchi, Nobuhiro Nishino, Ryuya Ikezoe, Akio Sanpei, Haruhiko Himura, Sadao Masamune, Observation of Simple Helical Structure in Low Aspect Ratio RFP Using Fast Camera, Plasma and Fusion Research, 3, 5, 2008.01.
14. Takumi Onchi, Akio Sanpei, Ryuya Ikezoe, Haruhiko Himura, Sadao Masamune, Application of Soft X-Ray Imaging System to the STE-2 RFP, Plasma and Fusion Research, 2, S1063, 2007.11.
Membership in Academic Society
  • American Physical Society
  • The Physical Society of Japan
  • The Japan Society of Plasma Science and Nuclear Fusion Research