MF Researcher Database

Researchers Database

Advance

Urai　Hajime　

    Department of Electrical and Electronic Engineering　Professor
    Course of Electricity， Electronics and Communications　Professor
    Research Institute of Industrial Technology　Researcher
Last Updated :2025/04/20

Researcher Information

Degree

  • Ph.D. (Engineering)（1997/03 Tokyo Institute of Technology）

Research funding number

  • 50912094

ORCID ID

J-Global ID

Research Areas

  • Manufacturing technology (mechanical, electrical/electronic, chemical engineering) / Electrical power engineering
  • Energy / Applied plasma science

Academic & Professional Experience

  • 2023/04 - Today  Toyo UniversityFaculty of Science and Engineering, Department of Electrical Electronic and Computer EngineeringProfessor
  • 2021/04 - 2023/03  Daido UniversitySchool of Engineering Department of Electrical and Electronic EngineeringProfessor
  • 1997/04 - 2021/03  Hitachi, Ltd.,
  • 2008/08 - 2011/03  Tokyo Institute of TechnologyGlobal COE programCo-advisor

Education

  • 1994/04 - 1997/03  Tokyo Institute of Technology  Graduate School of Science and Engineering  Department of Electrical and Electronic Engineering
  • 1992/04 - 1994/03  Tokyo Institute of Technology  Graduate School of Science and Engineering  Department of Electrical and Electronic Engineering
  • 1988/04 - 1992/03  Tokyo Institute of Technology  School of Engineering  電気・電子工学科

Association Memberships

  • CIGRE   IEEE   The Institute of Electrical Engineers of Japan   

Published Papers

  • Toshiaki Sakuyama; Hiroyuki Kobayashi; Masanori Ishikawa; Hideyuki Kotsuji; Katsuhiko Shiraishi; Hajime Urai; Yasunori Tanaka
    Journal of Physics D: Applied Physics IOP Publishing 56 (40) 405503 - 405503 0022-3727 2023/07 [Refereed]
  • Hideyuki Kotsuji; Masanao Terada; Katsuhiko Shiraishi; Hajime Urai; Yasunobu Yokomizu
    IEEE Transactions on Dielectrics and Electrical Insulation Institute of Electrical and Electronics Engineers (IEEE) 30 (1) 393 - 402 1070-9878 2023/02 [Refereed]
  • Hideyuki Kotsuji; Mami Kuroda; Masanao Terada; Katsuhiko Shiraishi; Hajime Urai; Yasunobu Yokomizu
    IEEE Transactions on Plasma Science Institute of Electrical and Electronics Engineers (IEEE) 51 (2) 429 - 436 0093-3813 2023/02 [Refereed]
  • Reaction Products in SF6 Multi Mixture with C2F4-BN and Cu Vapor Decomposition at 300-3000 K: Approach to Dielectric Breakdown Property Evaluation
    Yasunobu Yokomizu; Naoto Kodama; Hajime Urai; Masanao Terada; Mami Kuroda
    13th International Workshop on High Voltage Engineering 2022/11
  • Masanao Terada; Hajime Urai; Masanori Ishikawa; Katsuhiko Shiraishi; Toshiaki Sakuyama; Hideyuki Kotsuji; Mami Kuroda; Tatsuya Ishii; Yasunobu Yokomizu
    IEEE Transactions on Power Delivery Institute of Electrical and Electronics Engineers (IEEE) 37 (5) 3885 - 3892 0885-8977 2022/10 [Refereed]
  • Yasuaki Aoyama; Yu Hasegawa; Katsuhiko Shiraishi; Hiroaki Hashimoto; Hajime Urai; Daisuke Ebisawa
    Electrical Engineering in Japan Wiley 215 (4) 0424-7760 2022/09
  • Toshiaki Sakuyama; Hiroyuki Kobayashi; Katsuhiko Shiraishi; Hajime Urai; Yasunori Tanaka
    2022 6th International Conference on Electric Power Equipment - Switching Technology (ICEPE-ST) IEEE 1-0692 78 - 82 2022/03 [Refereed]
  • Hideyuki Kotsuji; Mami Kuroda; Masanao Terada; Katsuhiko Shiraishi; Hajime Urai; Yasunobu Yokomizu
    2022 6th International Conference on Electric Power Equipment - Switching Technology (ICEPE-ST) IEEE 8-0710 117 - 120 2022/03 [Refereed]
  • Mami Kuroda; Yasunobu Yokomizu; Masanao Terada; Hideyuki Kotsuji; Katsuhiko Shiraishi; Hajime Urai
    2022 6th International Conference on Electric Power Equipment - Switching Technology (ICEPE-ST) IEEE 8-0577 108 - 111 2022/03 [Refereed]
  • Yasuaki Aoyama; Yu Hasegawa; Katsuhiko Shiraishi; Hiroaki Hashimoto; Hajime Urai; Daisuke Ebisawa
    IEEJ Transactions on Industry Applications Institute of Electrical Engineers of Japan (IEE Japan) 142 (3) 214 - 221 0913-6339 2022/03 [Refereed]
  • Hajime Urai; Naoki Osawa; Makoto Koizumi; Youichi Ooshita; Masanori Tsukushi; Noriyuki Yaginuma
    IEEJ Transactions on Power and Energy Institute of Electrical Engineers of Japan (IEE Japan) 141 (11) 666 - 675 0385-4213 2021/11 [Refereed]
  • Mami Kuroda; Tatsuya Ishii; Yuki Kojima; Yasunobu Yokomizu; Masanao Terada; Hideyuki Kotsuji; Hajime Urai
    IEEJ Transactions on Power and Energy Institute of Electrical Engineers of Japan (IEE Japan) 141 (11) 718 - 724 0385-4213 2021/11 [Refereed]
  • Development of an electrically-operating circuit breaker system using a linear motor
    Yasuaki Aoyama; Yu Hasegawa; Katsuhiko Shiraishi; Hiroaki Hashimoto; Hajime Urai; Daisuke Ebisawa
    IEEJ Joint Technical Meeting on Magnetics/Linear Drives 5 - 12 2021/06
  • Y Yokomizu; M Terada; N Kodama; T Ishii; Y Kojima; M Kuroda; H Urai
    Journal of Physics D: Applied Physics IOP Publishing 54 (16) 165204 - 165204 0022-3727 2021/02 [Refereed]
  • Hideyuki Kotsuji; Toshiaki Sakuyama; Masanao Terada; Hajime Urai
    IEEE Transactions on Plasma Science Institute of Electrical and Electronics Engineers (IEEE) 49 (2) 854 - 861 0093-3813 2021/02 [Refereed]
  • Toshiaki Sakuyama; Hideyuki Kotsuji; Masanao Terada; Katsuhiko Shiraishi; Hajime Urai
    IEEJ Transactions on Electrical and Electronic Engineering Wiley 16 (2) 215 - 225 1931-4973 2020/12 [Refereed]
  • Masanao Terada; Yuki Nakai; Hiroaki Hashimoto; Daisuke Ebisawa; Hajime Urai; Yasunobu Yokomizu
    Advances in Science, Technology and Engineering Systems Journal ASTES Journal 5 (4) 109 - 118 2415-6698 2020/07 [Refereed]
  • Masanao Terada; Hajime Urai; Yasunobu Yokomizu
    IEEE Transactions on Power Delivery Institute of Electrical and Electronics Engineers (IEEE) 35 (2) 707 - 714 0885-8977 2020/04 [Refereed]
  • Hiroyuki Kobayashi; Tatehito Usui; Toshiaki Sakuyama; Hideyuki Kotsuji; Katsuhiko Shiraishi; Hajime Urai
    IEEE Transactions on Plasma Science Institute of Electrical and Electronics Engineers (IEEE) 47 (11) 5064 - 5069 0093-3813 2019/11 [Refereed]
  • Mami Kuroda; Hajime Urai; Masanao Terada; Tatsuya Ishii; Yuki Kojima; Yasunobu Yokomizu
    2019 5th International Conference on Electric Power Equipment - Switching Technology (ICEPE-ST) IEEE I-2-5 551 - 554 2019/10 [Refereed]
  • Tatsuya Ishii; Masanao Terada; Yasunobu Yokomizu; Yuki Kojima; Mami Kuroda; Hajime Urai
    2019 5th International Conference on Electric Power Equipment - Switching Technology (ICEPE-ST) IEEE A-1-2 7 - 11 2019/10 [Refereed]
  • Toshiaki Sakuyama; Hiroyuki Kobayashi; Hideyuki Kotsuji; Katsuhiko Shiraishi; Hajime Urai
    2019 5th International Conference on Electric Power Equipment - Switching Technology (ICEPE-ST) IEEE A-2-1 22 - 25 2019/10 [Refereed]
  • Hideyuki Kotsuji; Toshiaki Sakuyama; Masanao Terada; Hajime Urai
    2019 5th International Conference on Electric Power Equipment - Switching Technology (ICEPE-ST) IEEE A-2-2 26 - 29 2019/10 [Refereed]
  • Masanao Terada; Yuki Nakai; Hiroaki Hashimoto; Daisuke Ebisawa; Hajime Urai; Yasunobu Yokomizu
    2019 5th International Conference on Electric Power Equipment - Switching Technology (ICEPE-ST) IEEE A-2-7 46 - 49 2019/10 [Refereed]
  • M. Terada; H. Urai; T. Nishimura; Y. Yokomizu
    PLASMA PHYSICS AND TECHNOLOGY Czech Technical University in Prague - Central Library 6 (2) 184 - 187 2336-2626 2019/09 [Refereed]
  • Collision Ionization and Electron Attachment Coefficients in High-Temperature SF6 Gas Mixture with Ablated PTFE/BN Vapor - Vapor concentration: 50% -
    Tatsuya Ishii; Yasunobu Yokomizu; Yuki Kojima; Masanao Terada; Hajime Urai; Mami Kuroda
    The Papers of Joint Technical Meeting on Plasma-Pulsed Power-Electrical Discharges, Switching and Protecting, High Voltage Eneineering, IEE Japan 2019/07
  • Hideyuki Kotsuji; Hajime Urai; Toshiaki Sakuyama; Katsuhiko Shiraishi; Noriyuki Yaginuma
    IEEJ Transactions on Electrical and Electronic Engineering Wiley 13 (10) 1440 - 1445 1931-4973 2018/05 [Refereed]
  • Koichiro Adachi; Toshiaki Sakuyama; Hajime Urai
    IEEE Transactions on Plasma Science Institute of Electrical and Electronics Engineers (IEEE) 45 (12) 3300 - 3305 0093-3813 2017/12 [Refereed]
  • Shusei Yokomichi; Masahiro Kozako; Masayuki Hikita; Kazuhiro Sato; Tomohiro Moriyama; Hajime Urai; Takashi Nakaoka; Kenji Tsuchiya
    2016 27th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV) IEEE C1-P-21 611 - 614 2016/09 [Refereed]
  • Capacitive Multi-probe for the Determination of Spatial Arc Voltage Distribution in Current Interrupting Phase of Gas Blast Circuit Breaker Model
    Koichiro Adachi; Toshiaki Sakuyama; Youichi Ooshita; Katsuhiko Shiraishi; Hajime Urai; Martin Forschelen
    21st International Conference on Gas Discharges and their Applications 255 - 258 2016/09 [Refereed]
  • Measurement of Gas Temperature in Self-blast Chamber using a Gas Circuit Breaker Model up to 60 kA Interruption
    Hideyuki Kotsuji; Hajime Urai; Toshiaki Sakuyama; Katsuhiko Shiraishi; Noriyuki Yaginuma
    21st International Conference on Gas Discharges and their Applications 243 - 246 2016/09 [Refereed]
  • Thermal Interruption Performance on High di/dt at Current Zero with Small Model Self-blast Interrupters
    Toshiaki Sakuyama; Kazuto Nakamura; Masanao Terada; Hideyuki Kotsuji; Katsuhiko Shiraishi; Hajime Urai
    21st International Conference on Gas Discharges and their Applications 231 - 234 2016/09 [Refereed]
  • Partial Discharge Phenomena in Medium Vacuum Region of Vacuum Interrupter Filled with Air toward to Application to Vacuum Leakage Detection
    Takashi Nakaoka; Shusei Yokomichi; Masahiro Kozako; Masayuki Hikita; Kazuhiro Sato; Tomohiro Moriyama; Hajime Urai; Kenji Tsuchiya
    The Papers of Joint Technical Meeting on Dielectrics and Electrical Insulation, Electric Wire and Power Cable Engineering, IEE Japan 1 - 6 2016/03
  • Measurement of Gas Temperature in Thermal Puffer Chamber Using a Self-blast Gas Circuit Breaker Model
    Hideyuki Kotsuji; Hajime Urai; Toshiaki Sakuyama; Katsuhiko Shiraishi; Noriyuki Yaginuma
    9th International Workshop on High Voltage Engineering 65 - 68 2014/11
  • Partial Discharge Phenomena in Medium Vacuum Region of Vacuum Interrupter and Application to Fault Diagnosis
    Takashi Nakaoka; Yuki Tai; Masahiro Kozako; Masayuki Hikita; Mohamad Kamarol; Kazuhiro Sato; Noriyuki Tetsu; Hajime Urai; Kenji Tsuchiya
    9th International Workshop on High Voltage Engineering 57 - 62 2014/11
  • M. Kamarol; Y. Tai; T. Nakaoka; M. Kozako; K. Sato; N. Tetsu; H. Urai; K. Tsuchiya; M. Hikita
    2014 International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV) IEEE C1-P-176 489 - 492 2014/09 [Refereed]
  • T. Nakaoka; Y. Tai; M. Kamarol; M. Kozako; M. Hikita; K. Sato; N. Tetsu; H. Urai; K. Tsuchiya
    2014 International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV) IEEE C1-P-154 485 - 488 2014/09 [Refereed]
  • Interrupter Size Effect on Current Zero Properties in Thermal Interruption of High Voltage Circuit Breakers
    Toshiaki Sakuyama; Hajime Urai; Hideyuki Kotsuji; Noriyuki Yaginuma; Masanori Tsukushi
    20th International Conference on Gas Discharges and Their Applications 143 - 146 2014/07 [Refereed]
  • Hajime Urai; Makoto Koizumi; Yoichi Ooshita; Noriyuki Yaginuma; Masanori Tsukushi
    2013 2nd International Conference on Electric Power Equipment - Switching Technology (ICEPE-ST) IEEE 1 - 4 2013/10 [Refereed]
  • Hiroaki HASHIMOTO; Hajime URAI; Kenichi OKUBO
    Journal of System Design and Dynamics Japan Society of Mechanical Engineers 7 (4) 456 - 471 2013/04 [Refereed]
  • Hiroaki HASHIMOTO
    TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series C Japan Society of Mechanical Engineers 79 (799) 691 - 703 0387-5024 2013/03 [Refereed]
  • Investigation of Size Effect on Thermal Interruption Performance in High-Voltage Circuit Breakers using Current Zero Measurement
    Toshiaki Sakuyama; Hajime Urai; Yoichi Ooshita; Makoto Koizumi; Noriyuki Yaginuma; Masanori Tsukushi
    he Papers of Joint Technical Meeting on Electrical Discharges, Static Apparatus, Switching and Protecting Engineering, IEE Japan 105 - 109 2012/06
  • Hajime Urai; Youichi Ooshita; Makoto Koizumi; Masanori Tsukushi
    IEEJ Transactions on Power and Energy Institute of Electrical Engineers of Japan (IEE Japan) 132 (5) 407 - 414 0385-4213 2012/05 [Refereed]
  • Hajime Urai; Youichi Ooshita; Makoto Koizumi; Noriyuki Yaginuma; Masanori Tsukushi
    2011 1st International Conference on Electric Power Equipment - Switching Technology IEEE 559 - 564 2011/10 [Refereed]
  • Evaluation of Thermal Interruption Capability with Re-ignition Voltage and Its Application to Experimental Design in SF6 Gas Circuit Breakers
    Hajime Urai; Youichi Ooshita; Makoto Koizumi; Masanori Tsukushi
    7th International Workshop on High Voltage Engineering 7 - 13 2010/11
  • Computational Arc and Fluid Dynamics Simulation of Spatial Dielectric Strength for Large Current Interruption in High-Voltage Circuit Breakers
    Hajime Urai; Makoto Koizumi; Youichi Ooshita; Noriyuki Yaginuma; Masanori Tsukushi; Yasunori Tanaka
    18th International Conference on Gas Discharges and Their Applications 106 - 109 2010/09 [Refereed]
  • Analysis of pressure rise in the thermal puffer chamber of a self-blast type gas circuit breaker using a hot gas flow simulation
    Naoki Osawa; Kazuya Taniguchi; Kasai Kazuki; Yoshio Yoshioka; Hajime Urai; Masanori Tsukushi
    The Papers of Joint Technical Meeting on Electrical Discharges, Static Apparatus, Switching and Protecting Engineering, IEE Japan 79 - 84 2010/06
  • Simulation of Extinction of Arc and Current Interruption in GCBs Using Pulsed Arc Microplasma
    Ryohei Saiki; Makoto Kanemaru; Noriaki Hashiguchi; Shinji Ibuka; Shozo Ishii; Hajime Urai
    The Papers of Joint Technical Meeting on Plasma, Pulsed Power, Electrical Discharges Engineering, IEE Japan 71 - 76 2009/11
  • Measurements of a dielectric recovery characteristic in a gas circuit breaker using small experimental equipment
    Takafumi Hosono; Hajime Urai; Makoto Koizumi; Oshita Yoichi; Masanori Tsukushi
    The Papers of Joint Technical Meeting on Electrical Discharges, Switching and Protecting, High Voltage Engineering, IEE Japan 59 - 63 2009/11
  • Evaluation of interruption performance for gas circuit breakers using arc and hot gas flow calculation with CIP scheme
    Hajime Urai; Makoto Koizumi; Noriyuki Yaginuma; Masanori Tsukushi
    The Papers of Joint Technical Meeting on Electrical Discharges, Static Apparatus, Switching and Protecting Engineering, IEE Japan 69 - 74 2009/06
  • Characterization of Pulsed Micro-Arc to Model the Extinction of Arc in Gas Blast Circuit Breakers
    Ryohei Saiki; Makoto Kanemaru; Noriaki Hashiguchi; Shinji Ibuka; Shozo Ishii; Hajime Urai
    The Papers of Joint Technical Meeting on Electrical Discharges, Switching and Protecting, High Voltage Engineering, IEE Japan 2009/06
  • Pulsed-Micro-Arc Extinction and Current Interruption by Gas Blasting
    Ryohei Saiki; Makoto Kanemaru; Shinji Ibuka; Shozo Ishii; Hajime Urai
    The Papers of Technical Meeting on Plasma, IEE Japan 2008/12
  • Estimation of 80 kA Short-line Fault Interrupting Capability in an SF6 Gas Circuit Breaker Based on Arc Model Calculation
    Hajime Urai; Yoichi Ooshita; Makoto Koizumi; Noriyuki Yaginuma; Masanori Tsukushi; Rene Peter Paul Smeets
    17th International Conference on Gas Discharges and Their Applications 129 - 132 2008/09 [Refereed]
  • Makoto Koizumi; Hajime Urai; Youichi Osita; Naoki Osawa; Masanori Tukushi; Noriyuki Yaginuma
    IEEJ Transactions on Power and Energy Institute of Electrical Engineers of Japan (IEE Japan) 127 (9) 1002 - 1008 0385-4213 2007/09 [Refereed]
  • Evaluation of an arc extinction performance with arc conductance at current-zero in a gas circuit breaker
    Hajime Urai; Yoichi Ooshita; Makoto Koizumi; Masanori Tsukushi
    The Papers of Joint Technical Meeting on Electrical Discharges, Static Apparatus, Switching and Protecting Engineering, IEE Japan 45 - 50 2007/07
  • Measurement of arc extinction performance with transient voltage around current-zero in a gas circuit breaker
    Hajime Urai; Naoki Oosawa; Youichi Ooshita; Masanori Tsukushi
    The Papers of Joint Technical Meeting on Electrical Discharges, Switching and Protecting, High Voltage Engineering, IEE Japan 1 - 5 2005/11
  • Makoto Koizumi; Hjime Urai; Masanori Tsukushi; Ryuya Ando; Noriyuki Yaginuma; Iwao Harada
    IEEJ Transactions on Power and Energy Institute of Electrical Engineers of Japan (IEE Japan) 121 (12) 1652 - 1660 0385-4213 2001 [Refereed]
  • Hajime Urai; Tadashi Kurosawa; Akitoshi Okino; Eiki Hotta; Hiroyuki Yasui; Toru Tamagawa; Kwang-cheol Ko
    Review of Scientific Instruments AIP Publishing 68 (9) 3346 - 3350 0034-6748 1997/09 [Refereed]
  • Urai Hajime; Kurosawa Tadashi; Okino Akitoshi; Hotta Eiki; Ko Kwang-Choel
    IEEE International Conference on Plasma Science 1996 [Refereed]
  • Plasma Properties of the DC Glow Discharge in Wire Ion Plasma Source
    Hajime Urai; Kenji Mashio; Akitoshi Okino; Eiki Hotta
    International Conference on Plasma Physics 1996
  • Hiroyuki Yasui; Tohru Tamagawa; Iwao Ohshima; Hajime Urai; Eiki Hotta
    Radiation Physics and Chemistry Elsevier BV 46 (4-6) 499 - 502 0969-806X 1995/10 [Refereed]
  • Monte Carlo Simulation and Experimental Study of the Breakdown Phase of a Low-Pressure Wire Discharge
    Hajime Urai; Tadashi Kurosawa; Akitoshi Okino; Eiki Hotta; Hiroyuki Yasui; Tohru Tamagawa
    11th International Conference on Gas Discharges and Their Applications 2-158 1995/08
  • A Collisional-Radiative Model for Diagnostics of a Wire Ion Plasma Source
    Hajime Urai; Kenji Mashio; Akitoshi Okino; Eiki Hotta; Hiroyuki Yasui; Tohru Tamagawa
    Korea-Japan International Workshop on the Plasma Technologies and Applications EP-95-97 1995
  • Plasma Properties and Electrical Characteristics of Low-pressure Wire Ion Plasma Source
    Hajime Urai; Kiyoshige Muramatsu; Tadashi Kurosawa; Akitoshi Okino; Eiki Hotta; Mitsuaki Maeyama; Hiroyuki Yasui; Tohru Tamagawa
    International Conference on Plasma Physics 3-69 1994/11
  • Hajime Urai S. Maeyama; Hiroyuki Yasui Hiroyuki Yasui; Tohru Tamagawa Tohru Tamagawa
    Japanese Journal of Applied Physics IOP Publishing 33 (7S) 4243 - 4243 0021-4922 1994/07 [Refereed]
  • DC Discharge Characteristics of Wire Ion Plasma Source
    Teruya Osawa; Hajime Urai; Mitsuaki S. Maeyama; Hiroyuki Yasui; Tohru Tamagawa; Eiki Hotta
    Journal of plasma and fusion research 70 (5) 506 - 513 1994/07 [Refereed]
  • DC Discharge Characteristics of Wire Ion Plasma Source
    Hajime Urai; Akitoshi Okino; Eiki Hotta; Hiroyuki Yasui; Tohru Tamagawa
    The Papers of Technical Meeting on Plasma, IEE Japan 1994
  • Effect of Axial magnetic Fields on Electrical Characteristics of a Low Pressure Wire Discharge
    Hajime Urai; Eiki Hotta; Mitsuaki S. Maeyama; Hiroyuki Yasui; Tohru Tamagawa
    2nd International Conference on Reactive Plasmas and 11th Symposium on Plasma Processing 1994/01
  • Effect of Axial Magnetic Field in a Wire Ion Plasma Source
    Hajime Urai; Tadashi Kurosawa; Eiki Hotta; Hiroyuki Yasui; Tohru Tamagawa
    The Papers of Technical Meeting on Plasma, IEE Japan 1993
  • Electrical Characteristics of Low Pressure Wire Discharge and an Ion Source
    Hiroyuki Yasui; Tohru Tamagawa; Iwao Ohshima; Mitsuaki S. Maeyama; Teruya Osawa; Hajime Urai; Eiki Hotta
    XXI International Conference on Phenomena in Ionized Gases II-341 1993
  • Yuanshing Liu; Hajime Urai; Syozou Ishii
    IEEJ Transactions on Fundamentals and Materials Institute of Electrical Engineers of Japan (IEE Japan) 113 (1) 17 - 24 0385-4205 1993/01 [Refereed]
  • Mote-Carlo Simulation of X-ray Radiation Process in Cold Cathode X-ray Sources
    Yuanshing Liu; Hajime Urai; Syozo Ishii
    The Papers of Technical Meeting on Plasma, IEE Japan 1992

Books etc

  • IEEJ Technical Report No. 1474 "Backgrounds and Reasons for Revision of JEC-2300 Alternating-current Circuit-breaker Standard"
    (Joint workChapter 1, 6, 7 and editing)The Institute of Electrical Engineers of Japan 2020/04
  • IEEJ Technical Report No. 1376 "Switching Phenomena and Requirements for High Voltage Circuit Breakers on Power Systems"
    (Joint workSection 3.3 (pp. 23 - 32))The Institute of Electrical Engineers of Japan 2016/04
  • IEEJ Technical Report No. 1312 "State of the Art of Worldwide Performance Investigation Technologies for Circuit Breakers"
    (Joint workChapter 5 (pp. 45 - 68))The Institute of Electrical Engineers of Japan 2014/07
  • IEEJ Technical Report No. 1200 "Guide for Application of JEC-2300"
    (Joint workSection 3.4 (pp. 79 - 90), Section (pp. 107 - 111))The Institute of Electrical Engineers of Japan 2010/09
  • IEEJ Technical Report No. 1116 "The Reliability of High Voltage Circuit Breaker and its Improvement Technology"
    (Joint workSection 4.3.2 (pp. 43 - 49 ), Section 5.1 (pp. 50 - 51))The Institute of Electrical Engineers of Japan 2008/05
  • IEEJ Technical Report No. 993 "State of the Art of Interruption Technologies for Circuit Breakers"
    (Joint workChapter 5 (pp. 19 - 38))The Institute of Electrical Engineers of Japan 2005/01
  • IEEJ Technical Report No. 865 "Technologies for Specific-use Circuit breakers and Their Application Status"
    (Joint workChapter 6 (pp. 28 - 39)，editing)The Institute of Electrical Engineers of Japan 2002/01

Conference Activities & Talks

  • Direct current limitation and interruption with model low-voltage circuit breaker constructed of SiC-MOSFET —current limiting resistor of 2–30 Ω—
    A. Sakai; Y. Yokomizu; N. Kodama; M. Iwata; A. Nakamura; H. Urai
    令和7年電気学会全国大会  2025/03  Oral presentation
  • Improvement of Fluoropolymer Adhesion by Atmospheric Plasma Treatment for Biomaterial Applications
    白井 晶都; 櫻田 尚月; 大澤 泰樹; 浦井 一; 金高弘恭
    2024年度生体医歯工学共同研究拠点成果報告会  2025/03
  • Development of Observable Atomosphere-Plasma-Jet Device for Resin Surface Treatment
    浦井 一; 町田 拳士朗; 小佐川隼翔; 石井直登; 沖野晃俊; 矢井田朱音
    2024年度生体医歯工学共同研究拠点成果報告会  2025/03
  • Development of switchgear considering environmental friendliness and safety, and arc simulation technology to support these developments  [Invited]
    Hajime Urai
    7th International Conference on Electric Power Equipment - Switching Technology, Plenary Lecture, PL-2  2024/11
  • Fundamental research on low-voltage DC interrupting method by high-speed current commutation using switching function of SiC-MOSFET –capacitance 1–100 µF–.  [Not invited]
    A. Sakai; Y. Yokomizu; N. Kodama; M. Iwata; A. Nakamura; K. Hasegawa; H. Urai
    Tokai-Section Join;Conference on Electrical;Electronics, Information;Related Engineering  2024/08  Oral presentation
  • 生体材料を均一処理するためのリニア型マルチガスプラズマ源の開発  [Not invited]
    古谷淳之介; 日原弘喜; 八井田朱音; 沖野晃俊; 浦井一; 上本道久
    令和5年度生体医歯工学共同研究拠点成果報告会  2024/03  Poster presentation
  • 樹脂表面改質のための大気圧プラズマジェットの電気的特性計測  [Not invited]
    浦井 一; 赤池 響; 中山 颯志朗; 沖野 晃俊
    令和5年度生体医歯工学共同研究拠点成果報告会  2024/03  Poster presentation
  • Development of atmospheric linear type plasma for fabrication of photonic biosensor  [Not invited]
    Koki Hihara; Junnosuke Furuya; Akane Yaida; Yusuke Itagawa; Nobuhiro Yoda; Hiroshi Kano; Hajime Urai; Nobuhiko Nishiyama; Akitoshi Okino
    8th International Symposium on Biomedical Engineering (ISBE2023)  Poster presentation
  • The recent development of arc plasma simulatioins and their prospects  [Not invited]
    Hajime Urai
    The 2023 Annual Meeting of I.E.E. Japan Symposium  2023/03  Nominated symposium
  • Development of Atmospheric Plasma Jet Device for Resin Surface Treatment  [Not invited]
    浦井一; 安達彩乃; 岡本侑大; 吉田悠真; 沖野晃俊; 劉智志
    令和4年度生体医歯工学共同研究拠点成果報告会  2023/03  Poster presentation
  • Effect on Withstand Voltage Performance by Arc-preconditioning for Gas Circuit Breaker  [Not invited]
    Hideyuki Kotsuji; Hajime Urai; Masanao Terada
    The 2020 Annual Meeting of I.E.E. Japan  2022/03  Oral presentation
  • ガス絶縁開閉装置における脱SF6化への取組 ～電流遮断技術の動向～
    浦井 一
    電気学会 東海支部研究フォーラム「電力システム対する雷・自然と環境問題に関する研究」  2022/02  Invited oral presentation
  • Analytical Consideration of Electron Avalanche in High-temperature SF6 Gas with Two Regions with Different Temperature and Pressure Conditions  [Not invited]
    Mami Kuroda; Hajime Urai; Masanao Terada; Yasunobu Yokomizu
    Thirty-First Annual Conference of Power & Energy Society IEE Japan  2020/09  Oral presentation
  • Measurement of Check Valve Motion in High-voltage Self-blast Gas Circuit Breaker  [Not invited]
    Toshiaki Sakuyama; Hideyuki Kotsuji; Masanori Ishikawa; Masanao Terada; Katsuhiko Shiraishi; Hajime Urai
    The 2020 Annual Meeting of I.E.E. Japan  2020/03  Oral presentation
  • Component Species in High-Temperature SF6 Gas Mixture with Ablated C2F4/BN and Copper Vapor - Electron-Collision Ionization Cross Section for CuF2 and CuF -  [Not invited]
    Tatsuya Ishii; Yasunobu Yokomizu; Naoto Kodama; Masanao Terada; Hajime Urai; Mami Kuroda
    The 2020 Annual Meeting of I.E.E. Japan  2020/03  Oral presentation
  • Critical Electric-Field Strength at Pressure of 1 and 8 MPa for Hot SF6 Gas Mixture with 80% Ablated C2F4/BN Vapor  [Not invited]
    Tatsuya Ishii; Yasunobu Yokomizu; Yuki Kojima; Takehiro Sugita; Masanao Terada; Hajime Urai; Mami Kuroda
    2019 Tokai-Section Joint Conference on Electrical, Electronics, Information, and Related Engineering  2019/09  Oral presentation
  • Ablation-model with Absorption and Reflection of Radiated Arc Energy for Thermo Fluid Simulation of Gas Circuit Breaker  [Not invited]
    Masanori Ishikawa; Hisashi Morooka; Katsuhiko Shiraishi; Hajime Urai
    The 2019 Annual Meeting of I.E.E. Japan  2019/03  Oral presentation
  • Evaluation of Gas Flow by Multi-point Pressure Measurement for Gas Circuit Breaker  [Not invited]
    Hideyuki Kotsuji; Toshiaki Sakuyama; Hajime Urai; Masanao Terada
    The 2019 Annual Meeting of I.E.E. Japan  2019/03  Oral presentation
  • Measurement of Ablation Gas Transportation with Optical Emission Spectroscopy for Gas Circuit Breaker  [Not invited]
    Toshiaki Sakuyama; Hiroyuki Kobayashi; Masanori Ishikawa; Hideyuki Kotsuji; Katsuhiko Shiraishi; Hajime Urai
    The 2019 Annual Meeting of I.E.E. Japan  2019/03  Oral presentation
  • Derivation of Critical Electric-Field Strength of High-Temperature SF6 Gas Mixture with 80% Ablated PTFE/BN Vapor  [Not invited]
    Tatsuya Ishii; Yuki Kojima; Yasunobu Yokomizu; Masanao Terada; Hajime Urai
    The 2019 Annual Meeting of I.E.E. Japan  2019/03  Oral presentation
  • Ionization and Attachment Coefficients of High-Temperature SF6 Gas Mixture with Ablated PTFE/BN Vapor - Temperature 1000 K -  [Not invited]
    Yuki Kojima; Tatsuya Ishii; Yasunobu Yokomizu; Masanao Terada; Hajime Urai
    The 2019 Annual Meeting of I.E.E. Japan  2019/03  Oral presentation
  • Arc Analysis of Behavior of Ablated Nozzle Material for Gas Circuit Breaker  [Not invited]
    Hirokazu Furui; Hajime Urai; Masanao Terada; Masanori Ishikawa
    The Twenty-Nineth Annual Conference of Power & Energy Society IEE Japan  2018/09  Oral presentation
  • Derivation of Critical Electric-Field Strength of High-Temperature SF6 Gas Mixture with 50% Ablated PTFE/BN Vapor  [Not invited]
    Tatsuya Ishii; Yasunobu Yokomizu; Yuki Kojima; Masanao Terada; Hajime Urai
    2018 Tokai-Section Joint Conference on Electrical, Electronics, Information, and Related Engineering  2018/09  Oral presentation
  • First Approach to Deviation of Critical Electric-Field Strength of High-Temperature SF6 Gas Contaminated with Large Amount of Ablated PTFE/BN Vapor  [Not invited]
    Tatsuya Ishii; Yasunobu Yokomizu; Yuki Kojima; Masanao Terada; Hajime Urai
    The 2018 Annual Meeting of I.E.E. Japan  2018/03  Oral presentation
  • Evaluation Method of Exhaust Characteristics for Gas Circuit Breaker  [Not invited]
    Masanao Terada; Hajime Urai; Yasunobu Yokomizu
    The 2018 Annual Meeting of I.E.E. Japan  2018/03  Oral presentation
  • Temperature Measurement in Thermal Interruption Region with Optical Emission Spectroscopy for Gas Circuit Breakers  [Not invited]
    Toshiaki Sakuyama; Hiroyuki Kobayashi; Katsuhiko Shiraishi; Hajime Urai
    平成30年 電気学会 全国大会  2018/03  Oral presentation
  • Investigation of Measurement of Spatial Arc Voltage Distribution on Current Interrupting Test with Capacitive Probes  [Not invited]
    Koichiro Adachi; Toshiaki Sakuyama; Katsuhiko Shiraishi; Hajime Urai
    The Twenty-Eighth Annual Conference of Power & Energy Society IEE Japan  2017/09  Oral presentation
  • Switching Technology in High-voltage Circuit Breakers  [Invited]
    Hajime Urai
    Workshop on Adnaced Power Equipment, Xi'an Jiaotong University Invited Lecture  2017/06  Public discourse
  • Simulation and Measurement for Development of High-Voltage Circuit Breakers  [Invited]
    Hajime Urai
    1st International Conference on Electrical Materials and Power Equipment  2017/05  Invited oral presentation
  • Study on the Characteristics of Electrodes Relative Motion for Gas Circuit Breaker
    Masanao Terada; Yuki Nakai; Hajime Urai
    The 2017 Annual Meeting of I.E.E. Japan  2017/03  Oral presentation
  • Improvement of Capacitive Current Switching Performance with Relative Movement of Electrodes in Gas Circuit Breaker
    Yuki Nakai; Masanao Terada; Hajime Urai
    IEEJ Meeting at Ibaraki Branch of Tokyo Chapter  2016/11  Oral presentation
  • Comparison of Partial Discharge Characteristics in Medium Vacuum Region of Vacuum Interrupter Sealed with Air and SF6 Gas  [Not invited]
    Syusei Yokomichi; Masahiro Kozako; Masayuki Hikita; Kazuhiro Sato; Tomohiro Moriyama; Hajime Urai; Kenji Tsuchiya
    The Twenty-Seventh Annual Conference of Power & Energy Society IEE Japan  2016/06  Oral presentation
  • ガス遮断器の遮断性能評価への気流解析技術の適用
    浦井 一
    第174回高電圧技術研究会  2016/03  Public discourse
  • 系統における開閉現象と高電圧遮断器の開閉責務：大電流遮断（TLF，脱調）
    浦井 一
    電気学会 電力・エネルギーフォーラム  2016  Public discourse
  • Study on the Propagation of Partial Discharge Current in Vacuum Interrupter  [Not invited]
    Shusei Yokomichi; Takashi Nakaoka; Yuki Tai; Masahiro Kozako; Masayuki Hikita; Kazuhiro Sato; Noriyuki Tetsu; Hajime Urai; Kenji Tsuchiya
    The 2015 Annual Meeting of I.E.E. Japan  2015/03  Oral presentation
  • Partial Discharge Characteristics by Vacuum Deterioration in Vacuum Interrupter  [Not invited]
    Takashi Nakaoka; Shusei Yokomichi; Yuki Tai; Masahiro Kozako; Masayuki Hikita; Kazuhiro Sato; Noriyuki Tetsu; Hajime Urai; Kenji Tsuchiya
    The 2015 Annual Meeting of I.E.E. Japan  2015/03  Oral presentation
  • Measurement of Internal Pressure Dependence on Partial Discharge Characteristics in Vacuum Interrupter  [Not invited]
    Shusei Yokomichi; Takashi Nakaoka; Kozako Masahiro; Masayuki Hikita; Kazuhiro Sato; Noriyuki Tetsu; Hajime Urai; Kenji Tsuchiya
    Forty-Sixth Symposium on Electrical and Electronic Insulating Materials and Applications in Systems  2015  Oral presentation
  • 真空遮断器・開閉器の技術動向／遮断器の性能評価技術に関する最近の国内外動向：研究開発段階における性能評価技術  [Not invited]
    浦井 一
    電気学会 電力・エネルギーフォーラム  2015  Public discourse
  • Construction of Partial Discharge Diagnostic Study in Paschen Left Region in Vacuum Interrupter  [Not invited]
    Mohamad Kamarol; Takashi Nakaoka; Kiichi Nishigouchi; Masahiro Kozako; Masayuki Hikita; Kazuhiro Sato; Noriyuki Tetsu; Hajime Urai; Kenji Tsuchiya
    The 2014 Annual Meeting of I.E.E. Japan  2014/03  Oral presentation
  • Measurement of Ozone Concentration Caused by Partial Discharge in Air  [Not invited]
    Takashi Nakaoka; Kiichi Nishigouchi; Mohamad Kamarol; Masahiro Kozako; Masayuki Hikita; Kazuhiro Sato; Noriyuki Tetsu; Hajime Urai; Kenji Tsuchiya
    The 2014 Annual Meeting of I.E.E. Japan  2013/03  Oral presentation
  • Three-dimensional Numerical Analysis Considering Arc Heating and Turbulent Viscosity in Gas Circuit Breaker  [Not invited]
    Yukou Suzuki; Hisashi Shindo; Noriyuki Yaginuma; Hajime Urai; Makoto Hirose; Nobuatsu Tanaka
    Ibaraki District Conference Published by The Japan Society of Mechanical Engineers  2013  Oral presentation
  • Study on the Relation Between Chamber Dimensions and Gas Blast Characteristics of Self-Blast Gas Circuit Breaker  [Not invited]
    Naoki Osawa; Takuya Mizukami; Yuusuke Mizumoto; Yoshio Yoshioka; Hajime Urai; Makoto Koizumi; Masanori Tsukushi
    The 2012 Annual Meeting of I.E.E. Japan  2012/03  Oral presentation
  • Calculation of hot gas in a thermal puffer chamber by a combination of pressure calculation program and compressible hot gas flow simulation program  [Not invited]
    Yuusuke Mizumoto; Naoki Osawa; Yoshio Yoshioka; Hajime Urai; Makoto Koizumi; Masanori Tsukushi
    IEED Japan Annual Meeting 2012  2012  Oral presentation
  • 交流遮断器改訂規格の適用ガイドおよび電力系統での遮断責務：発電機用遮断器  [Not invited]
    浦井 一
    電気学会 電力・エネルギーフォーラム  2012  Public discourse
  • Relation between blast pressure characteristic and the structure of thermal puffer chamber of self-blast type GCBs  [Not invited]
    Yuusuke Mizumoto; Akinori Kanetsuki; Naoki Osawa; Yoshio Yoshioka; Hajime Urai; Masanori Tsukushi
    The Twenty-Second Annual Conference of Power & Energy Society IEE Japan  2011/09  Oral presentation
  • Characterization of Arc Extinction Using Pulsed-Arc-Micro Discharge with Symmetrical Gas Blasting  [Not invited]
    Taichi Ito; Makoto Kanemaru; Shinji Ibuka; Shozo Ishii; Hajime Urai
    The 2011 Annual Meeting of I.E.E. Japan  2011/03  Oral presentation
  • Three-dimensional Numerical Analysis Considering Moving Objects in Gas Circuit Breaker Considering Arc Heating and Turbulent Viscosity  [Not invited]
    Hisashi Shindo; Kengo Umehara; Nobuatsu Tanaka; Noriyuki Yaginuma; Hajime Urai; Masanori Tsukushi
    Ibaraki District Conference Published by The Japan Society of Mechanical Engineers  2011  Oral presentation
  • 遮断器過渡現象解析：アークモデルを活用した遮断成否予測法
    浦井 一
    電気学会電力・エネルギー部門大会 募集型座談会  2010/08  Nominated symposium
  • Survey of Actual Specification for Generator Circuit Breaker  [Not invited]
    Hajime Urai; Kenji Kamei
    The 2010 Annual Meeting of I.E.E. Japan Symposium  2010/03  Nominated symposium
  • Transient Recovery Voltage Condition at Transformer Limited Fault Current Breaking  [Not invited]
    Hiroaki Kagawa; Koichi Takeda; Tatsuya Watanabe; Hajime Urai; Junzo Kida; Kenji Kamei; Takeshi Shinkai
    The 2010 Annual Meeting of I.E.E. Japan Symposium  2010/03  Nominated symposium
  • Application of Three-dimensional High-Temperature Gas Flow Analysis Using CIVA Method to Gas Circuit Breaker  [Not invited]
    Noriyuki Yaginuma; Seiji Matsumoto; Masanori Tsukushi; Hajime Urai; Takeshi Nishimura; Nobuatsu Tanaka
    Annual Conference of Fundamentals and Materials Society IEE Japan  2010  Oral presentation
  • Three-dimensional Numerical Analysis of High-Temperature and High-pressure Gas Flow in Gas Circuit Breakers  [Not invited]
    Kengo Umehara; Hisashi Sindo; Nobuatsu Tanaka; Noriyuki Yaginuma; Masanori Tsukushi; Hajime Urai
    Ibaraki District Conference Published by The Japan Society of Mechanical Engineers  2010  Oral presentation
  • An evaluation for thermal interruption capability of SF6 gas circuit breaker with Taguchi methods procedure  [Not invited]
    Hajime Urai; Yoichi Ooshita; Makoto Koizumi; Masanori Tsukushi
    The 2008 Annual Meeting of I.E.E. Japan  2009/03  Oral presentation
  • Pulsed Micro-arc Extinction and Current Interruption by CO2 Gas Blasting  [Not invited]
    Ryohei Saiki; Makoto Kanemaru; Shinji Ibuka; Shozo Ishii; Hajime Urai
    The 2009 Annual Meeting of I.E.E. Japan  2009/03  Oral presentation
  • Measurement of a characteristic of hot gas exhaust with arc energy by using a small model of gas circuit breaker  [Not invited]
    Hajime Urai; Makoto Koizumi; Yoichi Ooshita; Noriyuki Yaginuma; Masanori Tsukushi
    The 2009 Annual Meeting of I.E.E. Japan  2009/03  Oral presentation
  • Analysis of Arc Behavior Considering Dependency of Absorption Coefficient of Thermal Radiation on Temperature and Pressure  [Not invited]
    Makoto Koizumi; Hajime Urai; Youichi Ooshita; Masanori Tsukushi; Noriyuki Yaginuma
    The Twentieth Annual Conference of Power & Energy Society IEE Japan  2009  Oral presentation
  • 遮断器の信頼性とその向上技術：信頼性向上に関わる新技術（監視・ネットワーク）
    浦井 一
    電気学会関東支部講習会  2009  Public discourse
  • Characterization of Arc Extinction Using Pulsed Micro-Arc Discharge with CO2 Gas Blasting  [Not invited]
    Makoto Kanemaru; Ryohei Saiki; Shinji Ibuka; Hajime Urai; Shozo Ishii
    Fundamentals and Applications of Microplasmas  2009  Poster presentation
  • The Influence of Inlet Convergence Angle of Puffer Type Circuit Breaker on Arc Extinction Capability  [Not invited]
    Hajime Urai; Yasunori Tanaka; Masanori Tsukushi
    The 2007 Annual Meeting of I.E.E. Japan  2007/03  Oral presentation
  • Calculation of Small Capacitive Current Interruption Performance Using Gas Flow Simulation Considered with Puffer Compression  [Not invited]
    Hajime Urai; Makoto Koizumi; Yoichi Ooshita; Noriyuki Yaginuma; Masanori Tsukushi
    The Eighteenth Annual Conference of Power & Energy Society IEE Japan  2007  Oral presentation
  • Evaluation of arc extinction performance by current zero measurement and tandem arc model calculation for gas circuit breakers  [Not invited]
    Hajime Urai; Naoki Osawa; Youichi Ohshita; Masanori Tsukushi
    The Seventeenth Annual Conference of Power & Energy Society IEE Japan  2006/09  Oral presentation
  • Influence of nozzle materials on current interruption in a gas circuit breaker  [Not invited]
    Hajime Urai; Youichi Ooshita; Hisashi Morooka; Masanori Tsukushi
    The 2006 Annual Meeting of I.E.E. Japan  2006/03  Oral presentation
  • Gas Flow Analysis Considering Ablation of Nozzle Material - Existing of Moving Objects -  [Not invited]
    Makoto Koizumi; Hajime Urai; Yoichi Ohshita; Naoki Osawa; Noriyuki Yaginuma; Masanori Tsukushi
    The Seventeenth Annual Conference of Power & Energy Society IEE Japan  2006  Oral presentation
  • ガス遮断器の技術動向：解析評価技術の動向  [Not invited]
    浦井 一
    電気学会東海支部講習会  2006  Public discourse
  • Ground Fault Prediction for Gas Circuit Breaker Using Hot Gas Flow Simulation  [Not invited]
    Naoki Osawa; Hajime Urai; Makoto Koizumi; Youichi Ohshita; Masanori Tsukushi
    The Sixteenth Annual Conference of Power & Energy Society IEE Japan  2005/09  Oral presentation
  • Measurement of hot gas temperature using thermocouple in a gas circuit breaker  [Not invited]
    Hajime Urai; Naoki Osawa; Makoto Koizumi; Youichi Ooshita; Juzo Kida; Yoshikatsu Enokida
    The 2005 Annual Meeting of I.E.E. Japan  2005/03  Oral presentation
  • Gas Flow Analysis Considering Ablation of Nozzle Material  [Not invited]
    Makoto Koizumi; Hajime Urai; Yoichi Ohshita; Naoki Osawa; Junzo Kida; Makoto Hirose
    The 2005 Annual Meeting of I.E.E. Japan  2005/03  Oral presentation
  • Development of Dynamics Simulation of Spring Operating Mechanism for Gas Circuit Breaker  [Not invited]
    Hiroaki Hashimoto; Shinji Seto; Hajime Urai; Hideo Kawamoto; Junzo Kida; Makoto Hirose; Kenichi Okubo
    The Fourteenth Annual Conference of Power & Energy Society IEE Japan  2003/09  Oral presentation
  • Instructions of ATP/Mingw32 easy installer and its advanced features  [Not invited]
    Hajime Urai; Shinichi Kondo; Hiroshi Arita
    The 2003 Annual Meeting of I.E.E. Japan  2003/03  Oral presentation
  • Advanced technique integrated with a puffer pressure-rise and an operating mechanism simulation for gas circuit breakers  [Not invited]
    Hajime Urai; Makoto Koizumi; Hiroaki Hashimoto; Shinji Seto; Junzo Kida; Yoshikatsu Enokida
    The 2003 Annual Meeting of I.E.E. Japan  2003/03  Oral presentation
  • Development of a Numerical Calculation Method for Arc Behavior Considering Absorptive Power of SF6 Gas in Thermal Radiation  [Not invited]
    Makoto Koizumi; Ryuya Ando; Hajime Urai; Noriyuki Yaginuma; Masanori Tsukushi; Iwao Harada
    The Twelfth Annual Conference of Power & Energy Society IEE Japan  2001/09  Oral presentation
  • High-repetition-rate Pulsed Operation of a Wire Ion Plasma Source  [Not invited]
    Hajime Urai; Tadashi Kurosawa; Akitoshi Okino; Eiki Hotta; Kwang-Cheol Ko
    23rd IEEE International Conference on Plasma Science  1996/06  Poster presentation
  • Plasma Diagnostics of Wire Ion Plasma Source by a Langmuir Probe  [Not invited]
    Kenji Mashio; Hajime Urai; Hiromichi Nakayama; Akitoshi Okino; Eiki Hotta
    The 1996 Annual Meeting of I.E.E. Japan  1996/03  Oral presentation
  • High Repetition-rate Pulsed Operation of Wire Ion Plasma Source  [Not invited]
    Hajime Urai; Tadashi Kurosawa; Akitoshi Okino; Eiki Hotta; Hiroyuki Yasui; Tohru Tamagawa
    The 1996 Annual Meeting of I.E.E. Japan  1996/03  Oral presentation
  • Measurements of Energy Distributions of Electron Beam from the Electron Gun Equipped with a Wire Ion Plasma Source  [Not invited]
    Hajime Urai; Kiyoshige Muramatsu; Akitoshi Okino; Eiki Hotta; Hiroyuki Yasui; Tohru Tamagawa
    The 1995 Annual Meeting of I.E.E. Japan  1995/03  Oral presentation
  • Study on Control of the Breakdown Phenomena in a Wire Ion Plasma Source  [Not invited]
    Tadashi Kurosawa; Masato Ando; Hajime Urai; Eiki Hotta; Hiroyuki Yasui; Tohru Tamagawa
    The 1995 Annual Meeting of I.E.E. Japan  1995/03  Oral presentation
  • Electrical Characteristics of Breakdown Phase of a Wire Ion Plasma Source  [Not invited]
    Hajime Urai; Akitoshi Okino; Eiki Hotta; Kwang-Cheol Ko
    22nd IEEE International Conference on Plasma Science  1995  Poster presentation
  • Effect of Axial Magnetic Field on Discharge Characteristics in Wire Ion Plasma Source  [Not invited]
    Eiki Hotta; Hajime Urai; Tadashi Kurosawa; Mitsuaki S. Maeyama; Hiroyuki Yasui; Tohru Tamagawa
    The forty-first JSAP spring meeting  1994/03  Oral presentation
  • Characteristics of a Wire Ion Plasma Source and its Application to an Electron Gun  [Not invited]
    Hajime Urai; Tadashi Kurosawa; Eiki Hotta; Mitsuaki S. Maeyama; Hiroyuki Yasui; Tohru Tamagawa
    The 1994 Annual Meeting of I.E.E. Japan  1994/03  Oral presentation
  • Effect of Axial Magnetic Field on Characteristics of a Wire Ion Plasma Source  [Not invited]
    Hajime Urai; Tadashi Kurosawa; Eiki Hotta; Mitsuaki S. Maeyama; Hiroyuki Yasui; Tohru Tamagawa
    21st IEEE International Conference on Plasma Science  1994  Poster presentation
  • Characteristics of a Wire Ion Plasma Source [3]  [Not invited]
    Hajime Urai; Teruya Osawa; Mitsuaki Suzuki; Eiki Hotta; Hiroyuki Yasui; Tohru Tamagawa
    The 1993 Annual Meeting of I.E.E. Japan  1993/03  Oral presentation
  • Characteristics of a Wire Ion Plasma Source and a Secondary Emission Electron Gun  [Not invited]
    Eiki Hotta; Teruya Osawa; Hajime Urai; Mitsuaki Suzuki Maeyama Hiroyuki Yasui; Tohru Tamagawa
    20th IEEE International Conference on Plasma Science  1993  Poster presentation
  • Characteristics of a Wire Ion Plasma Source  [Not invited]
    Eiki Hotta; Teruya Osawa; Hajime Urai; Mitsuaki Suzuki; Hiroyuki Yasui; Tohru Tamagawa
    The thirty-nineth JSAP spring meeting  1992/03  Oral presentation
  • Mote-Carlo Simulation of X-ray Generation Process in E-beam Bombarded X-ray Sources  [Not invited]
    Yuanshing Liu; Hajime Urai; Syozo Ishii
    The 1992 Annual Meeting of I.E.E. Japan  1992/03  Oral presentation

MISC

  • Hajime URAI; Mikimasa IWATA  The Journal of The Institute of Electrical Engineers of Japan  144-  (8)  502  -503  2024/08
  • Atmospheric Plasma Jet for Electrical-insulation Resin Surface Treatment
    Hajime URAI; Zhizhi LIU; Taiki OSAWA; Akitoshi OKINO; Hiroki KOJIMA  工業技術(東洋大学工業技術研究所報告)  (46)  2024/03
  • Development trends on the SF6-free technology for switching equipment for the electric power system
    Hajime Urai  Bulletin of Daido University  58-  1  -12  2023/03
  • Hajime Urai  IEEJ Transactions on Power and Energy  142-  (5)  239  -242  2022/05
  • Hajime Urai; Takanori Iijima; Kunihiko Tomiyasu; Takashi Inagaki; Gaku Asanuma  IEEJ Transactions on Power and Energy  141-  (11)  650  -655  2021/11
  • 2019 5th International on Electrical Power Equipment - Switching Technology (ICEPE-ST 2019)
    Hajime Urai  Electrical Insulation News in Asia  26-  21  -24  2019/12
  • Numerical Simulation of Electric Power Transmission and Distribution Equipment
    Hajime Urai; Takahide Matsuo; Hiroaki Hashimoto; Tatsuro Kato  Hitachi Review  95-  (12)  24  -27  2013/12
  • Hajime Urai; Norimitsu Kato; Masatomo Ono; Toshimasa Maruyama; Masayuki Sakaki; Masatoshi Nakajima  IEEJ Transactions on Power and Energy  133-  (11)  794  -798  2013/11
  • Arc and Hot Gas Flow Simulation to Evaluate Interruption Performance for Gas Circuit Breakers
    Masanori Tsukushi; Hajime Urai; Makoto Koizumi  AE POWER REVIEW  4-  30  -33  2011/07
  • 18th International Conference on Gas Discharges and Their Applications (GD2010)
    Akiko Kumada; Yasunori Tanaka; Hajime Urai; Ryo Ono; Nozomi Takeuchi; Koki Satoh  Journal of The Institute of Engineers on Electrical Discharge in Japan  53-  (4)  3  -9  2010/12
  • 17th International Conference on Gas Discharges and Their Applications (GD 2008)
    Kunihiko Hidaka; Yasunori Tanaka; Akiko Kumada; Shu-ichi Hamano; Haruo Shindo; Kouki Satoh; Hideki Ueno; Yoshiharu Nakamura; Hajime Urai; Susumu Nishiwaki  Journal of The Institute of Engineers on Electrical Discharge in Japan  51-  (3)  1  -19  2008/12
  • Numerical Simulation for Electric Power Plant Systems
    Kengo Iwashige; Hisashi Hamatake; Motoo Aoyama; Kenji Yamamoto; Hajime Urai  Hitachi Review  90-  (11)  66  -71  2008/11
  • Applying Flow Analysis Technology for Gas Circuit Breakers (GCB)
    Makoto Koizumi; Hajime Urai; Masanori Tsukushi  AE POWER REVIEW  2-  2008

Industrial Property Rights

  • 特許US12034379:POWER CONVERSION SYSTEM  
    Hajime Urai, Hiroshi Kamizuma, Kimihisa Furukawa, Noriya Nakao, Kinya Nakatsu
  • 特許7504761:POWER CONVERSION SYSTEM  
    浦井 一, 中尾 矩也, 上妻 央, 古川 公久, 富安 邦彦, 中津 欣也
  • 特許7303139:電力変換システム  
    浦井 一, 上妻 央, 古川 公久, 中尾 矩也, 中津 欣也
  • 特許6989449:Gas circuit breaker  
    Hisashi Morooka, Hajime Urai, Katsuhiko Shiraishi, Toshiaki Sakuyama, Yuichiro Yamane, Takahiro Nishimura
  • 特許6914801:Gas circuit breaker  
    Toshiaki Sakuyama, Hajime Urai, Masano Terada, Ryoichi Shiobara, Takahiro Nishimura, Makoto Hirose, Yuichiro Yamane
  • 特許6913639:Gas circuit breaker  
    Hisashi Morooka, Toshiaki Sakuyama, Katsuhiko Shiraishi, Hajime Urai, Takahiro Nishimura, Yuichiro Yamane
  • 特許6901425:Gas circuit breaker  
    Toshiaki Sakuyama, Masanao Terada, Hajime Urai, Yuichiro Yamane, Takahiro Nishimura
  • 特許US10916394:Gas circuit breaker  
    Toshiaki Sakuyama, Hajime Urai, Masano Terada, Ryoichi Shiobara, Takahiro Nishimura, Makoto Hirose, Yuichiro Yamane
  • 特許6830363:Gas circuit breaker  
    Hideyuki Kotsuji, Hajime Urai, Masanao Terada, Makoto Hirose
  • 特許6824028:Gas circuit breaker  
    Masanao Terada, Taichiro Yamashita, Hiroaki Hashimoto, Hajime Urai, Makoto Hirose
  • 特許6818604:Gas circuit breaker  
    Toshiaki Sakuyama, Ryoichi Shiobara, Hajime Urai, Makoto Hirose, Masanao Terada, Takahiro Nishimura
  • 特許US10699863:Gas circuit breaker  
    Toshiaki Sakuyama, Masanao Terada, Hajime Urai, Yuichiro Yamane, Takahiro Nishimura
  • 特許6667370:Gas circuit breaker  
    Yuki Nakai, Masanao Terada, Hajime Urai, Takashi Iida, Noriyuki Yaginuma
  • 特許6596360:Gas circuit breaker  
    Yuki Nakai, Masanao Terada, Hajime Urai
  • 特許6568775:Gas circuit breaker  
    Masanao Terada, Katsuhiko Shiraishi, Hajime Urai
  • 特許6564331:Gas circuit breaker  
    Toshiaki Sakuyama, Masanao Terada, Hajime Urai
  • 特許US10354821:Gas circuit breaker  
    Toshiaki Sakuyama, Ryoichi Shiobara, Hajime Urai, Makoto Hirose, Masanao Terada, Takahiro Nishimura
  • 特許US10256060:Gas circuit breaker  
    Masanao Terada, Taichiro Yamashita, Hiroaki Hashimoto, Hajime Urai, Makoto Hirose
  • 特許6476073:Gas circuit breaker  
    Kazuto Nakamura, Hajime Urai, Toshiaki Sakuyama, Hideyuki Kotsuji, Makoto Hirose
  • 特許US10199188:Gas circuit breaker  
    Masanao Terada, Yuki Nakai, Yoichi Ooshita, Hiroaki Hashimoto, Hajime Urai, Katsuhiko Shiraishi
  • 特許US10157719:Gas circuit breaker  
    Yuki Nakai, Masanao Terada, Hajime Urai, Takashi Iida, Noriyuki Yaginuma
  • 特許6435227:Gas circuit breaker  
    Toshiaki Sakuyama, Hajime Urai, Katsuhiko Shiraishi, Hideyuki Kotsuji, Kazuto Nakamura, Makoto Hirose
  • 特許6426114:Gas circuit breaker  
    Masanao Terada, Hajime Urai, Daisuke Ebisawa, Hiroaki Hashimoto, Riichi Nagao
  • 特許6397700:Vacuum valve pressure diagnostic device or vacuum valve device  
    Kazuhiro Sato, Ayumu Morita, Hajime Urai, Kenji Tsuchiya
  • 特許6364358:Gas circuit breaker  
    Masanao Terada, Yuki Nakai, Yoichi Ooshita, Hiroaki Hashimoto, Hajime Urai, Katsuhiko Shiraishi
  • 特許6364364:Switchgear  
    Takafumi Hosono, Ayumu Morita, Hajime Urai, Takashi Sato, Kenji Tsuchiya
  • 特許6363038:Gas circuit breaker  
    Hideyuki Kotsuji, Hajime Urai, Katsuhiko Shiraishi, Toshiaki Sakuyama, Makoto Hirose
  • 特許US9959999:Method for controlling power switching apparatus  
    Koichiro Adachi, Hajime Urai, Katsuhiko Shiraishi, Masataka Sasaki
  • 特許US9899172:Circuit breaker and circuit breaker operating method  
    Hajime Urai, Yasuaki Aoyama, Hiroaki Hashimoto, Katsuhiko Shiraishi, Tatsuro Kato, Ayumu Morita, Toshiaki Rokunohe, Yoichi Ooshita
  • 特許US9870884:Gas circuit breaker  
    Masanao Terada, Hajime Urai, Daisuke Ebisawa, Hiroaki Hashimoto, Riichi Nagao
  • 特許6266448:Gas circuit breaker  
    Masanao Terada, Katsuhiko Shiraishi, Hajime Urai, Yoichi Ooshita
  • 特許6186432:Operating method of puffer type gas circuit breaker  
    Hideyuki Kotsuji, Hajime Urai, Masanori Tsukushi, Hiroaki Hashimoto, Yasuaki Aoyama, Katsuhiko Shiraishi, Daisuke Ebisawa
  • 特許6132744:Gas circuit breaker  
    Masanao Terada, Masanori Tsukushi, Yoichi Ooshita, Katsuhiko Shiraishi, Hajime Urai
  • 特許US9620315:Gas circuit breaker  
    Masanao Terada, Hajime Urai, Katsuhiko Shiraishi, Yoichi Ooshita, Hiroaki Hashimoto, Noriyuki Yaginuma
  • 特許6069510:Gas circuit breaker  
    Masanao Terada, Hajime Urai, Katsuhiko Shiraishi, Yoichi Ooshita, Hiroaki Hashimoto, Noriyuki Yaginuma
  • 特許US9520699:Switchgear  
    Hajime Urai, Yasuaki Aoyama, Hiroaki Hashimoto, Tatsuro Kato, Ayumu Morita, Toshiaki Rokunohe, Yoichi Ooshita
  • 特許6012713:Circuit breaker and circuit breaker operating method  
    Hajime Urai, Yasuaki Aoyama, Hiroaki Hashimoto, Katsuhiko Shiraishi, Tatsuro Kato, Ayumu Morita, Toshiaki Rokunohe, Yoichi Ooshita
  • 特許US9336974:Gas circuit breaker  
    Hideyuki Kotsuji, Hajime Urai, Makoto Koizumi, Makoto Hirose
  • 特許5883516:Switchgear  
    Yasuaki Aoyama, Akiyoshi Komura, Hajime Urai, Katsuhiko Shiraishi, Yoichi Ooshita
  • 特許5826379:Switchgear  
    Hajime Urai, Yasuaki Aoyama, Hiroaki Hashimoto, Tatsuro Kato, Ayumu Morita, Toshiaki Rokunohe, Yoichi Ooshita
  • 特許5775966:Gas circuit breaker  
    Hajime Urai, Yasuaki Aoyama, Hiroaki Hashimoto, Katsuhiko Shiraishi, Tatsuro Kato, Ayumu Morita, Toshiaki Rokunohe, Yoichi Ooshita
  • 特許5482613:Gas breaker  
    Toshiaki Sakuyama, Hajime Urai, Yoichi Ooshita, Makoto Koizumi, Noriyuki Yaginuma, Ken Sato, Makoto Hirose
  • 特許5261198:Gas breaker  
    Masahiro Yaegashi, Yoichi Ooshita, Hajime Urai, Takafumi Hosono, Makoto Koizumi, Ken Sato
  • 特許5117735:Gas circuit breaker with preinsertion resistor  
    Naoki Osawa, Hajime Urai, Yoichi Ooshita, Makoto Hirose, Satoshi Ishiguro, Masanori Tsukushi
  • 特許4703616:Electric power opening and closing device and gas insulation circuit-breaker  
    Hiroaki Hashimoto, Kenichi Okubo, Seiji Matsumoto, Yaegashi Masahiro, Hajime Urai
  • 特許4634259:Puffer type gas circuit breaker  
    Naoki Osawa, Hajime Urai, Yoichi Ooshita, Junzo Kida, Hisashi Morooka
  • 特許US7339132:Method of current interruption using puffer type gas circuit breaker with combined-action of cylinder and piston  
    Hajime Urai, Youichi Ooshita, Makoto Koizumi, Naoki Osawa, Hiroaki Hashimoto, Kida Junzo

Awards & Honors

  • 2024/09 電気学会 電気学会電力・エネルギー部門論文査読貢献賞

Research Grants & Projects

Teaching Experience

  • Advanced Physics of Electric Discharge and High Voltage Engineering
    Toyo University
  • Electromagnetics 2
    Toyo University
  • Electrical, Electronic and Communications Experiments 3
    Toyo University
  • 電気回路特論 Advanced Electric Circuits
    Toyo University
  • Electric Power Engineering 1
    Toyo University
  • Numerical Algorithms
    Toyo University
  • Electric Circuits 1
    Toyo University
  • Electric and Electronic Mathematics 2
    Daido University
  • Power Electronics
    Daido University
  • Electric Power Equipment Engineering
    Daido University
  • Electric Circuit Theory 2
    Daido University
  • Electrical and Electronic Circuits
    Daido University

Committee Membership

  • 2024/09 - Today   8th International Conference on Electric Power Equipment - Switching Technology, Local Organizing Committee   Vice chairperson
  • 2024/09 - Today   CIGRE Janapese Technical Commitee SC A3   Member
  • 2023/06 - Today   IEE of Japan   Technical Committee on Smart Facilities, Primary member
  • 2022/06 - Today   IEE of Japan   Power and Energy Society R&D Steering Committee, Member
  • 2022/06 - Today   IEE of Japan   Technical Committee on Switching and Protection Technology, Chair
  • 2013/04 - Today   IEE of Japan   Technical Paper Committee B2 Group, Member
  • 2022/10 -2024/09   IEE of Japan   Study Committee "Application of Sensing Technology to High Voltage Circuit Breakers and its Applications", Member
  • 2023/04 -2024/05   Technical Committee of ATEEE-2024, The 2024 2nd International Conference of Advanced Technology of Electrical Engineering and Energy   Member
  • 2022/11 -2023/09   IEE of Japan   Organizing Committee of 2023 Annual Conference of Power and Energy Society, Secretary
  • 2021/03 -2023/08   30th Inernational Symposium on Discharges and Electrical Insulation in Vacuum   Local Organizing Committee Member
  • 2022/09 -2023/03   IEE of Japan   Organizing Committee of 2023 IEEJ Annual Conference
  • 2022/06   Norwegian University of Science and Technology   PhD Assessment Committee Member and 1st Opponent, Naghme Dorraki: "Investigation on Fault Current Making in Medium Voltage Switchgear in Air"
  • 2021/04 -2022/05   IEE of Japan   Technical Committee on Switching and Protection Technology, Primary member
  • 2010/04 -2021/03   IEE of Japan   Technical Committee on Switching and Protection Technology, Secretary
  • 2019/10   5th International Conference on Electric Power Equipment – Switching Technology   Local Organizing Committee Secretary
  • 2017/04 -2019/09   IEE of Japan   Study Committee “Backgrounds and Reasons for Revision of JEC–2300 Alternating-current Circuit-breaker Standard”, Secretary
  • 2016/09   21st International Conference on Gas Discharges and their Applications   Local Organizing Committee Secretary
  • 2012/04 -2014/09   IEE of Japan   Study Committee “Switching Phenomena and Requirements for High Voltage Circuit Breakers on Power Systems”, Member
  • 2013/10   2nd International Conference on Electric Power Equipment - Switching Technology   Local Organizing Committee Member
  • 2009/11 -2012/01   IEE of Japan   Study Committee “State of the Art of Worldwide Performance Investigation Technologies for Circuit Breakers", Member
  • 2007/11 -2009/10   IEE of Japan   Study Committee “Guide for Application of JEC–2300”, Member
  • 2004/04 -2007/07   IEE of Japan   Study Committee “The Reliability of High Voltage Circuit Breaker and its Improvement Technology", Member
  • 2001/04 -2004/03   IEE of Japan   Study Committee “State of the Art of Interruption Technologies for Circuit Breakers", Member
  • 1999/04 -2001/03   IEE of Japan   Study Commitee "Technologies for Specific-use Circuit Breakers and Their Application Status" Member

Other link

researchmap