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Sueoka, Shigeru; Kawakami, Tetsuo*; Suzuki, Kota*; Kagami, Saya; Yokoyama, Tatsunori; Shibazaki, Bunichiro*; Nagata, Mitsuhiro; Yamazaki, Ayu*; Higashino, Fumiko*; King, G. E.*; et al.
Fisshion, Torakku Nyusureta, (36), p.1 - 3, 2023/12
no abstracts in English
Ohshima, Hiroyuki; Morishita, Masaki*; Aizawa, Kosuke; Ando, Masanori; Ashida, Takashi; Chikazawa, Yoshitaka; Doda, Norihiro; Enuma, Yasuhiro; Ezure, Toshiki; Fukano, Yoshitaka; et al.
Sodium-cooled Fast Reactors; JSME Series in Thermal and Nuclear Power Generation, Vol.3, 631 Pages, 2022/07
This book is a collection of the past experience of design, construction, and operation of two reactors, the latest knowledge and technology for SFR designs, and the future prospects of SFR development in Japan. It is intended to provide the perspective and the relevant knowledge to enable readers to become more familiar with SFR technology.
Yuguchi, Takashi*; Sueoka, Shigeru; Iwano, Hideki*; Izumino, Yuya*; Ishibashi, Masayuki; Danhara, Toru*; Sasao, Eiji; Hirata, Takafumi*; Nishiyama, Tadao*
Journal of Asian Earth Sciences, 169, p.47 - 66, 2019/01
Times Cited Count:15 Percentile:64.05(Geosciences, Multidisciplinary)This study presents position-by-position paths within a granitic pluton based on thermochronological data, and describes their constraints and their relationship with fracture frequency, as an example from the Toki granite, central Japan. The cooling paths have position-specific characteristics; a single path does not represent the cooling behavior of the entire pluton. Such position-specific paths enable us to evaluate three-dimensional thermal evolution within the granitic pluton, and thus can clarify the detailed formation history of the entire pluton after the incipient intrusion of the granitic magma into the shallow crust. This study reveals the relationship between position-specific paths and fracture frequency, and thus provides a criterion for evaluating the fracture population in terms of thermal stress.
Kobayashi, Tatsuya*; Ito, Kimitaka*; Ido, Takeshi*; Kamiya, Kensaku; Ito, Sanae*; Miura, Yukitoshi; Nagashima, Yoshihiko*; Fujisawa, Akihide*; Inagaki, Shigeru*; Ida, Katsumi*; et al.
Scientific Reports (Internet), 6, p.30720_1 - 30720_7, 2016/08
Times Cited Count:13 Percentile:64.47(Multidisciplinary Sciences)In this Letter, we report model verifications for a key physics for the L-H transition. Radial electric field excitation, using discharges having a two-step transition. Examining time derivative of Poissons equation, it is found that the sum of the loss cone loss current and neoclassical bulk viscosity current agrees the experimentally observed current in the order of magnitude at the first transition. Following second transition and an ambipolar condition in the L-mode cannot be explained by the models.
Shibata, Masahiro; Sawada, Atsushi; Tachi, Yukio; Makino, Hitoshi; Wakasugi, Keiichiro; Mitsui, Seiichiro; Kitamura, Akira; Yoshikawa, Hideki; Oda, Chie; Ishidera, Takamitsu; et al.
JAEA-Research 2014-030, 457 Pages, 2015/03
JAEA and NUMO have conducted a collaborative research work which is designed to enhance the methodology of repository design and post-closure performance assessment in preliminary investigation stage. With regard to (1) study on rock suitability in terms of hydrology, based on some examples of developing method of hydro-geological structure model, acquired knowledge are arranged using the tree diagram, and model uncertainty and its influence on the evaluation items were discussed. With regard to (2) study on scenario development, the developed approach for "defining conditions" has been reevaluated and improved from practical viewpoints. In addition, the uncertainty evaluation for the effect of use of cementitious material, as well as glass dissolution model, was conducted with analytical evaluation. With regard to (3) study on setting radionuclide migration parameters, based on survey of precedent procedures, multiple-approach for distribution coefficient of rocks was established, and the adequacy of the approach was confirmed though its application to sedimentary rock and granitic rock. Besides, an approach for solubility setting was developed including the procedure of selection of solubility limiting solid phase. The adequacy of the approach was confirmed though its application to key radionuclides.
Kobayashi, Tatsuya*; Ito, Kimitaka*; Ido, Takeshi*; Kamiya, Kensaku; Ito, Sanae*; Miura, Yukitoshi; Nagashima, Yoshihiko*; Fujisawa, Akihide*; Inagaki, Shigeru*; Ida, Katsumi*; et al.
Nuclear Fusion, 54(7), p.073017_1 - 073017_14, 2014/07
Times Cited Count:26 Percentile:77.22(Physics, Fluids & Plasmas)In the JFT-2M tokamak, limit-cycle oscillation among several variables is observed before L-to-H transition. Spatiotemporal dynamics of the LCO is analyzed in detail. Zonal fows are not seen, and modulation in edge-localized poloidal flow and density gradient is observed. Modulation is also seen in Reynolds stress, caused by that in turbulence intensity and turbulence wavenumber. However, flow acceleration is not able to be explained by the modulation in the Reynolds stress. Rapid inward propagation in density gradient and turbulence packet is also observed. Characteristics of the propagation are veried by means of turbulence spreading theory and diffusion theory.
Shibata, Masahiro; Sawada, Atsushi; Tachi, Yukio; Hayano, Akira; Makino, Hitoshi; Wakasugi, Keiichiro; Mitsui, Seiichiro; Oda, Chie; Kitamura, Akira; Osawa, Hideaki; et al.
JAEA-Research 2013-037, 455 Pages, 2013/12
Following FY2011, JAEA and NUMO have conducted a collaborative research work which is designed to enhance the methodology of repository design and performance assessment in preliminary investigation stage. With regard to (1) study on rock suitability in terms of hydrology, the tree diagram of methodology of groundwater travel time has been extended for crystalline rock, in addition, tree diagram for sedimentary rock newly has been organized. With regard to (2) study on scenario development, the existing approach has been improved in terms of a practical task, and applied and tested for near field focusing on the buffer. In addition, the uncertainty of some important processes and its impact on safety functions are discussed though analysis. With regard to (3) study on setting radionuclide migration parameters, the approaches for parameter setting have been developed for sorption for rocks and solubility, and applied and tested through parameter setting exercises for key radionuclides.
Kunimaru, Takanori; Mikake, Shinichiro; Nishio, Kazuhisa; Tsuruta, Tadahiko; Matsuoka, Toshiyuki; Ishibashi, Masayuki; Sasao, Eiji; Hikima, Ryoichi; Tanno, Takeo; Sanada, Hiroyuki; et al.
JAEA-Review 2013-018, 169 Pages, 2013/09
Japan Atomic Energy Agency (JAEA) at Tono Geoscience Center (TGC) is pursuing a geoscientific research and development project namely the Mizunami Underground Research Laboratory (MIU) Project in crystalline rock environment in order to construct scientific and technological basis for geological disposal of High-level Radioactive Waste (HLW). The MIU Project has three overlapping phases: Surface-based Investigation phase (Phase I), Construction phase (Phase II), and Operation phase (Phase III). The MIU Project has been ongoing the Phase II and the Phase III in 2011 fiscal year. This report shows the results of the investigation, construction and collaboration studies in fiscal year 2011, as a part of the Phase II and Phase III based on the MIU Master Plan updated in 2010.
Kobayashi, Tatsuya*; Ito, Kimitaka*; Ido, Takeshi*; Kamiya, Kensaku; Ito, Sanae*; Miura, Yukitoshi; Nagashima, Yoshihiko*; Fujisawa, Akihide*; Inagaki, Shigeru*; Ida, Katsumi*; et al.
Physical Review Letters, 111(3), p.035002_1 - 035002_5, 2013/07
Times Cited Count:94 Percentile:94.33(Physics, Multidisciplinary)In this Letter, we report analyses of spatiotemporal dynamics of turbulence and structure in the limit cycle oscillation that precedes L-to-H transition. Zonal flows are not observed during LCO, and the oscillation is the periodic generations/decays of barrier with edge localized mean flow. Oscillatory Reynolds stress is found too small to accelerate the LCO flow. Changes of the density gradient and turbulence amplitude are found to propagate into the core in a ballistic manner, suggesting a cause of fast change of core transport after H-mode transition.
Shibata, Masahiro; Sawada, Atsushi; Tachi, Yukio; Makino, Hitoshi; Hayano, Akira; Mitsui, Seiichiro; Taniguchi, Naoki; Oda, Chie; Kitamura, Akira; Osawa, Hideaki; et al.
JAEA-Research 2012-032, 298 Pages, 2012/09
JAEA and NUMO have conducted a collaborative research work which is designed to enhance the methodology of repository design and performance assessment in preliminary investigation phase. The topics and the conducted research are follows; (1) Study on selection of host rock: in terms of hydraulic properties, items for assessing rock property, and assessment methodology of groundwater travel time has been organized with interaction from site investigation. (2) Study on development of scenario: the existing approach has been embodied, in addition, the phenomenological understanding regarding dissolution of and nuclide release from vitrified waste, corrosion of the overpack, long-term performance of the buffer are summarized. (3) Study on setting nuclide migration parameters: the approach for parameter setting has been improved for sorption and diffusion coefficient of buffer/rock, and applied and tested for parameter setting of key radionuclides. (4) Study on ensuring quality of knowledge: framework for ensuring quality of knowledge has been studied and examined aimed at the likely disposal facility condition.
Setoodehnia, K.*; Chen, A. A.*; Komatsubara, Tetsuro*; Kubono, Shigeru*; Binh, D. N.*; Carpino, J. F.*; Chen, J.*; Hashimoto, Takashi*; Hayakawa, Takehito; Ishibashi, Yoko*; et al.
Physical Review C, 83(1), p.018803_1 - 018803_4, 2011/01
Times Cited Count:12 Percentile:60.75(Physics, Nuclear)The structure of proton-unbound S states strongly determines the thermonuclear P(, )S reaction rate at temperatures characteristic of explosive hydrogen burning in classical novae and type I X-ray bursts. Specifically, the rate had been previously predicted to be dominated by two low-lying, unobserved, levels in the =4.7-4.8 MeV region, with spin and parity assignments of 3 and 2. In recent experimental work, two candidate levels were observed with energies of 4.699 MeV and 4.814 MeV, but no experimental information on their spins and parities was obtained. We have performed an in-beam -ray spectroscopy study of S with the Si(He, )S reaction. The spin and parities were inferred from a comparison to the known decay schemes of the corresponding mirror states.
Kawamura, Makoto; Makino, Hitoshi; Sasao, Eiji; Niizato, Tadafumi; Yasue, Kenichi; Asamori, Koichi; Umeda, Koji; Ishimaru, Tsuneari; Osawa, Hideaki; Ebashi, Takeshi; et al.
JAEA-Research 2010-027, 85 Pages, 2010/09
Japan Atomic Energy Agency (JAEA) have developed a formal evaluation method to assess the potential impacts of natural phenomena (earthquakes and faulting; volcanism; uplift, subsidence, denudation and sedimentation; climatic and sea-level changes) on a high level radioactive waste (HLW) disposal system for the purpose of maintenance of evaluation method for potential impacts of natural phenomena within more realistic view. In this report, we developed a framework as a part of the total system performance assessment for two purposes: the first one is quantification of relationship of characteristic of natural phenomena between geological environmental conditions (T-H-M-C-G), and the other one is quantification of relationship of T-H-M-C-G condition between parameters of performance assessment. We tried to apply the framework to all natural phenomena to confirm the effectiveness of the framework. On the other hand, we applied an argument-diagram that was developed one of the methods of the knowledge management to elicit future tasks. As a result, to apply the framework, we could show that information integration could carry out efficiently, and information integration was attained by the common framework by combining information on geohistory and existing information of natural phenomena and geological environmental conditions as modern-analogue. We could show that suitable scenarios might be chosen by information integration. Furthermore, we were able to elicit future tasks to this study by applying the argument-diagram.
Saito, Shigeru; Kikuchi, Kenji*; Hamaguchi, Dai; Usami, Koji; Ishikawa, Akiyoshi; Nishino, Yasuharu; Endo, Shinya; Kawai, Masayoshi*; Dai, Y.*
Journal of Nuclear Materials, 398(1-3), p.49 - 58, 2010/03
Times Cited Count:6 Percentile:40.28(Materials Science, Multidisciplinary)In several institutes, R&D for an ADS have been progressed. Ferritic / martensitic (F/M) steels are the candidate material for the beam window. To obtain the irradiation data, the PIE work of the SINQ target irradiation program (STIP) specimens was carried out at JAEA. In this study, the results of PIE on F/M steel F82H and its welded joint will be reported. The results of tensile tests indicate that the irradiation hardening occurred with increasing dpa up to 10.1 dpa below 320C irradiation. At higher dose (- 11.8 dpa) and higher temperature (- 380C), irradiation hardening and degradation of ductility relaxed. In this study, all specimens kept its ductility after irradiation and fractured in ductile manner. The fatigue life of F82H base metal is almost the same as that of unirradiated specimens. Though the number of specimen is limited, the fatigue life of F82H EB welded joints seems to increase after irradiation. The fracture surfaces of the specimens showed transgranular morphology. While F82H TIG welded specimens were not fractured by 10 cycles.
Makino, Takahiro; Kobayashi, Daisuke*; Hirose, Kazuyuki*; Takahashi, Daisuke*; Ishii, Shigeru*; Kusano, Masaki*; Onoda, Shinobu; Hirao, Toshio; Oshima, Takeshi
IEEE Transactions on Nuclear Science, 56(6), p.3180 - 3184, 2009/12
Times Cited Count:13 Percentile:64.74(Engineering, Electrical & Electronic)SET-induced soft-error rates (s) of logic LSIs are estimated from SET pulse-widths measured in logic cells used in logic LSIs. The estimated rates are consistent with directly measured s for logic LSIs.
Makino, Takahiro*; Kobayashi, Daisuke*; Hirose, Kazuyuki*; Yanagawa, Yoshimitsu*; Saito, Hirobumi*; Ikeda, Hirokazu*; Takahashi, Daisuke*; Ishii, Shigeru*; Kusano, Masaki*; Onoda, Shinobu; et al.
IEEE Transactions on Nuclear Science, 56(1), p.202 - 207, 2009/02
Times Cited Count:36 Percentile:90.64(Engineering, Electrical & Electronic)SET pulse-widths were measured as a function of LET by using pulse capture circuits and were simulated with mixed-mode 3-D device simulations. We found that the carrier recombination process dominates LET dependence of SET pulse-widths.
Rintsu, Yuko*; Serizawa, Shigeru*; Yamazaki, Tetsuo*; Umeyama, Nobuaki*; Moriuchi, Shigeru*; Handa, Hiroyuki*; Onishi, Ryoichi*; Takemura, Morio*; Chino, Masamichi; Nagai, Haruyasu; et al.
Proceedings of 16th Pacific Basin Nuclear Conference (PBNC-16) (CD-ROM), 6 Pages, 2008/10
no abstracts in English
Makino, Takahiro*; Yanagawa, Yoshimitsu*; Kobayashi, Daisuke*; Fukuda, Seisuke*; Hirose, Kazuyuki*; Ikeda, Hirokazu*; Saito, Hirobumi*; Onoda, Shinobu; Hirao, Toshio; Oshima, Takeshi; et al.
Shingaku Giho, 108(100), p.67 - 72, 2008/06
SET pulse-widths were measured as a function of LET by using pulse capture circuits. In addition, a scan flip-flop (FF) is designed to observe both single event transient (SET) and single event upset (SEU) soft errors in logic VLSI system.
Hoshino, Katsumichi; Suzuki, Takahiro; Isayama, Akihiko; Ide, Shunsuke; Takenaga, Hidenobu; Kubo, Hirotaka; Fujita, Takaaki; Kamada, Yutaka; Fujii, Tsuneyuki; Tsuda, Takashi; et al.
Fusion Science and Technology, 53(1), p.114 - 129, 2008/01
Times Cited Count:2 Percentile:16.99(Nuclear Science & Technology)We report on the applications of the ECH to the JT-60U tokamak. The ECH contributes to the advanced tokamak study in JT-60U in such respects as (1)NTM suppression, (2)Study on the internal transport barrier, (3)Impurity exhaust, (4)Tokamak start-up without center solenoid, (5)Current hole study, (6)Confinement and transport study, and (7)Start-up and shut-down assist. These contributions comes from the good local coupling of the ECH to the tokamak plasma.
Tsuchiya, Kunihiko; Hoshino, Tsuyoshi; Kawamura, Hiroshi; Mishima, Yoshinao*; Yoshida, Naoaki*; Terai, Takayuki*; Tanaka, Satoru*; Munakata, Kenzo*; Kato, Shigeru*; Uchida, Munenori*; et al.
Nuclear Fusion, 47(9), p.1300 - 1306, 2007/09
Times Cited Count:23 Percentile:62.01(Physics, Fluids & Plasmas)no abstracts in English
Tsuchiya, Kunihiko; Hoshino, Tsuyoshi; Kawamura, Hiroshi; Mishima, Yoshinao*; Yoshida, Naoaki*; Terai, Takayuki*; Tanaka, Satoru*; Munakata, Kenzo*; Kato, Shigeru*; Uchida, Munenori*; et al.
Proceedings of 21st IAEA Fusion Energy Conference (FEC 2006) (CD-ROM), 8 Pages, 2007/03
no abstracts in English