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Kamikawa, Yutaka; Suzuki, Makoto; Agake, Toshiki; Murakami, Takahiko; Morita, Yusuke; Shiina, Hidenori; Fukushima, Manabu; Hirane, Nobuhiko; Ouchi, Yasuhiro
JAEA-Technology 2023-030, 57 Pages, 2024/03
Owing to the publication of the latest data about aircraft crashes by Nuclear Regulation Authority (NRA), it was necessary to re-evaluate the probabilities of aircraft crashes for Nuclear Science Research Institute (NSRI). By using of the assessment method provided in "Regulatory Guide of the Assessment Standard for Probability of Airplane Crash on a Nuclear Power Reactor Facility", we re-evaluated the probabilities of aircraft crashes against the nuclear facilities in NSRI. As a result of the evaluations, the sum of the probabilities of aircraft crashes against Waste Treatment Facilities (maximum probability among all nuclear facilities in NSRI) is 5.6810
(times/(reactor
year)) which is lower than 10
(times/(reactor
year)) that is the assessment criterion whether aircraft crashes is considered to be "anticipated external human induced events" in design basis or not.
Haraga, Tomoko; Ouchi, Kazuki; Sato, Yoshiyuki; Hoshino, Hitoshi*; Tanana, Rei*; Fujihara, Takashi*; Kurokawa, Hideki*; Shibukawa, Masami*; Ishimori, Kenichiro; Kameo, Yutaka; et al.
Analytica Chimica Acta, 1032, p.188 - 196, 2018/11
Times Cited Count:13 Percentile:45.12(Chemistry, Analytical)The development of safe, rapid and highly sensitive analytical methods for radioactive samples, especially actinide (An) ions, represents an important challenge. Here we propose a methodology for selecting appropriate emissive probes for An ions with very low consumption and emission of radioactivity by capillary electrophoresis-laser-induced fluorescence detection (CE-LIF), using a small chemical library of probes with eight different chelating moieties. It was found that the emissive probe, which possesses the tetradentate chelating moiety, was suitable for detecting uranyl ions. The detection limit for the uranyl-probe complex using CE-LIF combined with dynamic ternary complexation and on-capillary concentration techniques was determined to be 0.7 ppt. This method was successfully applied to real radioactive liquid samples collected from nuclear facilities.
Ikeda, Yoshitaka; Hanada, Masaya; Kamada, Masaki; Kobayashi, Kaoru; Umeda, Naotaka; Akino, Noboru; Ebisawa, Noboru; Inoue, Takashi; Honda, Atsushi; Kawai, Mikito; et al.
IEEE Transactions on Plasma Science, 36(4), p.1519 - 1529, 2008/08
Times Cited Count:12 Percentile:43.06(Physics, Fluids & Plasmas)The JT-60SA N-NBI system is required to inject 10 MW for 100 s at 500 keV. Three key issues should be solved for the JT-60SA N-NBI ion source. One is to improve the voltage holding capability. Recent R&D tests suggested that the accelerator with a large area of grids may need a high margin in the design of electric field and a long time for conditioning. The second issue is to reduce the grid power loading. It was found that some beamlets were strongly deflected due to beamlet-beamlet interaction and strike on the grounded grid. The grids are to be designed by taking account of beamlet-beamlet interaction in three-dimensional simulation. Third is to maintain the D- production for 100 s. A simple cooling structure is proposed for the active cooled plasma grid, where a key is the temperature gradient on the plasma grid for uniform D- production. The modified N-NBI ion source will start on JT-60SA in 2015.
Kikuchi, Katsumi; Akino, Noboru; Ebisawa, Noboru; Ikeda, Yoshitaka; Seki, Norikazu*; Takenouchi, Tadashi; Tanai, Yutaka
JAEA-Technology 2008-034, 25 Pages, 2008/04
The control system for auxiliary pumping facility and primary water cooling facility in JT-60 NBI was updated. To realize the cost reduction, the control system with many input and outputs of 2000 was updated by JAEA itself using commercial Programmable Logic Controllers (PLC's). JAEA also made software with 3600 ladder lines by JAEA itself based on commercial basic programs. In addition to the simple replacement of the hardware and software, the function of remote operation has been newly added. At present, the auxiliary pumping facility and the primary water cooling facility have been stably operated without troubles. The remote operation enables to collect the detailed information on the trouble more easily, resulting in a quick countermeasure for the trouble.
Honda, Atsushi; Okano, Fuminori; Oshima, Katsumi; Akino, Noboru; Kikuchi, Katsumi; Tanai, Yutaka; Takenouchi, Tadashi; Numazawa, Susumu*; Ikeda, Yoshitaka
Fusion Engineering and Design, 83(2-3), p.276 - 279, 2008/04
Times Cited Count:11 Percentile:58.02(Nuclear Science & Technology)The control system of the cryogenic facility in the JT-60 NBI system has been renewed by employing the PLC (Programmable Logic Controller) and SCADA (Supervisory Control And Data Acquisition) system. The original control system was constructed about 20 years ago by specifying the DCS (Distributed Control System) computer to deal with 400 feedback loops. Recently, troubles on this control system have increased due to its aged deterioration. To maintain a high reliability of the cryogenic facility, a new control system has been intended with PLC and SCADA system. By optimizing the function blocks and connecting them in the FBD language, the feedback loops in the new control system have been successfully replaced from DCS to PLC without software developer. At present, the new control system has worked well. This is the first application of the marketable PLC to the actual system with feedback loops of 400 produced by the user itself.
Hanada, Masaya; Kamada, Masaki; Akino, Noboru; Ebisawa, Noboru; Honda, Atsushi; Kawai, Mikito; Kazawa, Minoru; Kikuchi, Katsumi; Komata, Masao; Mogaki, Kazuhiko; et al.
Review of Scientific Instruments, 79(2), p.02A519_1 - 02A519_4, 2008/02
Times Cited Count:6 Percentile:31.68(Instruments & Instrumentation)A long pulse production of high-current, high-energy D ion beams was studied in the JT-60U negative ion source that was designed to produce 22 A, 500 keV D
ion beams. Prior to the long pulse production, the short pulse beams were produced to examine operational ranges for a stable voltage holding capability and an allowable grid power loading. From a correlation between the voltage holding capability and a light intensity of cathodoluminescence from the insulator made of Fiber Reinforced Plastic insulator, the voltage holding was found to be stable at
340 kV where the light was sufficiently suppressed. The grid power loading for the long pulse operation was also decreased to the allowable level of
1 MW without a significant reduction of the beam power by tuning the extraction voltage (Vext) and the arc power (Parc). These allow the production of 30 A D
ion beams at 340 keV from two ion sources at Vacc = 340 kV. The pulse length was extended step by step, and finally reached up to 21 s, where the beam pulse length was limited by the surface temperature of the beam scraper without water cooling. The D
ion beams were neutralized to via a gas cell, resulting in a long pulse injection of 3.2 MW D
beams for 21 s. This is the first long injection of
20 s in a power range of
3 MW.
Ikeda, Yoshitaka; Akino, Noboru; Ebisawa, Noboru; Hanada, Masaya; Inoue, Takashi; Honda, Atsushi; Kamada, Masaki; Kawai, Mikito; Kazawa, Minoru; Kikuchi, Katsumi; et al.
Fusion Engineering and Design, 82(5-14), p.791 - 797, 2007/10
Times Cited Count:24 Percentile:82.10(Nuclear Science & Technology)Modification of JT-60U to a superconducting device (so called JT-60SA) has been planned to contribute to ITER and DEMO. The NBI system is required to inject 34 MW for 100 s. The upgraded NBI system consists of twelve positive ion based NBI (P-NBI) units and one negative ion based NBI (N-NBI) unit. The injection power of the P-NBI units are 2 MW each at 85 keV, and the N-NBI unit will be 10 MW at 500 keV, respectively. On JT-60U, the long pulse operation of 30 s at 2 MW (85 keV) and 20 s at 3.2 MW (320 keV) have been achieved on P-NBI and N-NBI units, respectively. Since the temperature increase of the cooling water in both ion sources is saturated within 20 s, further pulse extension up to 100 s is expected to mainly modify the power supply systems in addition to modification of the N-NBI ion source for high acceleration voltage. The detailed technical design of the NBI system for JT-60SA is presented.
Ikeda, Yoshitaka; Umeda, Naotaka; Akino, Noboru; Ebisawa, Noboru; Grisham, L. R.*; Hanada, Masaya; Honda, Atsushi; Inoue, Takashi; Kawai, Mikito; Kazawa, Minoru; et al.
Nuclear Fusion, 46(6), p.S211 - S219, 2006/06
Times Cited Count:62 Percentile:87.42(Physics, Fluids & Plasmas)Recently, the extension of the pulse duration up to 30 sec has been intended to study quasi-steady state plasma on JT-60U N-NBI system. The most serious issue is to reduce the heat load on the grids for long pulse operation. Two modifications have been proposed to reduce the heat load. One is to suppress the beam spread which may be caused by beamlet-beamlet interaction in the multi-aperture grid due to the space charge force. Thin plates were attached on the extraction grid to modify the local electric field. The plate thickness was optimized to steer the beamlet deflection. The other is to reduce the stripping loss, where the electron of the negative ion beam is stripped and accelerated in the ion source and then collides with the grids. The ion source was modified to reduce the pressure in the accelerator column to suppress the beam-ion stripping loss. Up to now, long pulse injection of 17 sec for 1.6 MW and 25 sec for 1 MW has been obtained by one ion source with these modifications.
Honda, Atsushi; Okano, Fuminori; Oshima, Katsumi; Akino, Noboru; Kikuchi, Katsumi; Tanai, Yutaka; Takenouchi, Tadashi; Numazawa, Susumu*
JAEA-Technology 2006-020, 20 Pages, 2006/03
no abstracts in English
Matsuda, Makoto; Takeuchi, Suehiro; Tsukihashi, Yoshihiro; Hanashima, Susumu; Abe, Shinichi; Osa, Akihiko; Ishizaki, Nobuhiro; Tayama, Hidekazu; Nakanoya, Takamitsu; Kabumoto, Hiroshi; et al.
Proceedings of 3rd Annual Meeting of Particle Accelerator Society of Japan and 31st Linear Accelerator Meeting in Japan, p.275 - 277, 2006/00
no abstracts in English
Kikuchi, Katsumi*; Akino, Noboru; Ikeda, Yoshitaka; Oga, Tokumichi; Oshima, Katsumi*; Okano, Fuminori; Takenouchi, Tadashi*; Tanai, Yutaka*; Honda, Atsushi
Heisei-16-Nendo Osaka Daigaku Sogo Gijutsu Kenkyukai Hokokushu (CD-ROM), 4 Pages, 2005/03
no abstracts in English
Miura, Yukitoshi; ; ; Hoshino, Katsumichi; ; ; Kasai, Satoshi; Kawakami, Tomohide; Kawashima, Hisato; Maeda, M.*; et al.
Fusion Energy 1996, p.167 - 175, 1997/05
no abstracts in English
; ; ; ; ; ; ; Oikawa, Toshihiro; ; ; et al.
Fusion Energy 1996, p.885 - 890, 1997/05
no abstracts in English
Oga, Tokumichi; ; ; ; Ito, Takao; ; Kawai, Mikito; ; Komata, Masao; Kunieda, Shunsuke; et al.
JAERI-Tech 95-044, 147 Pages, 1995/09
no abstracts in English
; Ando, Toshiro; ; Arai, Takashi; Neyatani, Yuzuru; Yoshino, Ryuji; Tsuji, Shunji; Yagyu, Junichi; Kaminaga, Atsushi; ; et al.
Journal of Nuclear Materials, 220-222, p.390 - 394, 1995/00
Times Cited Count:16 Percentile:80.48(Materials Science, Multidisciplinary)no abstracts in English
Shibanuma, Kiyoshi; ; Dairaku, Masayuki; ; Matsuda, Shinzaburo; Ouchi, Yutaka; ; Shibata, Takemasa
Nihon Genshiryoku Gakkai-Shi, 33(12), p.1171 - 1179, 1991/12
Times Cited Count:1 Percentile:19.81(Nuclear Science & Technology)no abstracts in English
Shibanuma, Kiyoshi; ; Dairaku, Masayuki; Ouchi, Yutaka; Shibata, Takemasa
JAERI-M 91-180, 39 Pages, 1991/10
no abstracts in English
Shibanuma, Kiyoshi; ; Dairaku, Masayuki; Kunieda, Shunsuke; Kuriyama, Masaaki; Matsuda, Shinzaburo; Ouchi, Yutaka; Shibata, Takemasa; Shirakata, Hirofumi
Nihon Genshiryoku Gakkai-Shi, 33(10), p.960 - 974, 1991/10
Times Cited Count:1 Percentile:19.81(Nuclear Science & Technology)no abstracts in English
Matsuoka, Mamoru; ; ; ; Kawai, Mikito; Komata, Masao; Kunieda, Shunsuke; Kuriyama, Masaaki; Mizuno, Makoto; Oga, Tokumichi; et al.
JAERI-M 90-086, 112 Pages, 1990/06
no abstracts in English
; ; ; ; Ouchi, Yutaka; Ohara, Yoshihiro; Kunieda, Shunsuke; Kuriyama, Masaaki; Shibanuma, Kiyoshi; Seki, Masahiro; et al.
JAERI-M 90-056, 19 Pages, 1990/03
no abstracts in English