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Nakajima, Toru; Kawakami, Tetsuo*; Iwano, Hideki*; Danhara, Toru*; Sakai, Harutaka*
Journal of Geophysical Research; Solid Earth, 127(5), p.e2021JB023630_1 - e2021JB023630_33, 2022/05
Times Cited Count：1 Percentile：22.72(Geochemistry & Geophysics)The thermochronological methods were applied to the Higher Himalayan Crystalline (HHC) nappe and the underlying Lesser Himalayan sediments (LHS) to elucidate the denudation process of the middle- and upper-crust of eastern Nepal over the geological time scale. The thermochronological inverse analysis was undertaken for new results of fission-track (FT) age and FT length data of zircon and apatite in order to reconstruct the time-temperature (
) paths in the temperature range of 60-350 degree. Eight paths obtained along the across-strike section showed that the cooling process of the HHC nappe was characterized by following three aspects: (1) gradual cooling followed by rapid cooling and subsequent gradual cooling, (2) northward-younging of the timing of the rapid cooling, (3) gradual cooling followed by ca. 2 Myr rapid cooling in the frontmost part of the HHC nappe. The observed FT ages and paths were then compared with those predicted by forward thermokinematic modeling. The results of the thermokinematic modeling for the Flat-Ramp-Flat MHT model, in which the HHC and the underlying LHS are denudated accompanied with the movement of the Main Himalayan Thrust (MHT), well reproduced the observed paths and FT ages in eastern Nepal. This suggests that the observed FT ages and paths reflect a denudation process driven by the movement of the MHT showing the flat-ramp-flat geometry, and that the denudation rate and its spatial distribution have roughly been constant in eastern Nepal since ca. 9 Ma.
Kobata, Masaaki; Okane, Tetsuo; Nakajima, Kunihisa; Suzuki, Eriko; Owada, Kenji; Kobayashi, Keisuke*; Yamagami, Hiroshi; Osaka, Masahiko
Journal of Nuclear Materials, 498, p.387 - 394, 2018/01
Times Cited Count：17 Percentile：86.67(Materials Science, Multidisciplinary)In this study, for the understandings of Cesium (Cs) adsorption behavior on structure materials in severe accidents at a light water nuclear reactor, the chemical state of Cs and its distribution on the surface of SUS304 stainless steel (SS) with different Si concentration were investigated by hard X-ray photoelectron spectroscopy (HAXPES) and scanning electron microscope / energy dispersive X-ray spectroscopy (SEM/EDX). As a result, it was found that Cs is selectively adsorbed at the site where Si distributes with high concentration. CsFeSiO
is a dominant Cs products in the case of low Si content, mainly formed, while Cs
SiO
and CsSiO
are formed in addition to CsFeSiO in the case of high Si content. The chemical forms of the Cs compounds produced in the adsorption process on the SS surface has a close correlation with the concentration and chemical states of Si originally included in SS.
Osaka, Masahiko; Nakajima, Kunihisa; Miwa, Shuhei; Di Lemma, F. G.*; Miyahara, Naoya; Suzuki, Chikashi; Suzuki, Eriko; Okane, Tetsuo; Kobata, Masaaki
Proceedings of 8th European Review Meeting on Severe Accident Research (ERMSAR 2017) (Internet), 11 Pages, 2017/05
Fundamental research on fission product (FP) chemistry is underway at Japan Atomic Energy Agency. The purpose is to establish a FP chemistry database in each region of a LWR under severe accident conditions. Improvement of FP chemical models based on this database is also an important task of the research. Research outputs are reflected to the research and development of decommissioning of Fukushima Daiichi Nuclear Power Station (1F) and the enhancement of LWR safety. Four research items have thus been established considering the specific issues of 1F and the priority in the source term research area, as follows: - Effects of boron (B) release kinetics and thermal-hydraulic conditions on FP behavior, - Cesium (Cs) chemisorption and reactions with structural materials, - Establishment of a thermodynamic and thermophysical properties database for FP compounds, - Development of experimental and analytical techniques for the reproduction of FP behavior. In this paper, results and progress of the research are presented.
Osaka, Masahiko; Miwa, Shuhei; Nakajima, Kunihisa; Di Lemma, F. G.*; Suzuki, Chikashi; Miyahara, Naoya; Kobata, Masaaki; Okane, Tetsuo; Suzuki, Eriko
JAEA-Review 2016-026, 32 Pages, 2016/12
JAEA-Review-2016-026.pdf:6.18MB
A fundamental research program on fission product (FP) chemistry has started since 2012 for the purpose of establishment of a FP chemistry database in each region of LWR under severe accident and improvement of FP chemical models based on the database. Research outputs are reflected as fundamental knowledge to both the research and development of decommissioning of Fukushima Daiichi Nuclear Power Station (1F) and enhancement of LWR safety. Four research items have thus been established considering the specific issues of 1F and the priority in the source term research area, as follows: effects of boron (B) release kinetics and thermal-hydraulic conditions on FP behavior, cesium (Cs) chemisorption and reactions with structural materials, enlargement of a thermodynamic and thermophysical properties database for FP compounds and development of experimental and analytical techniques for the reproduction of FP behavior and for direct measurement methods of chemical form of FP compounds. In this report, the research results and progress for the year 2015 are described. The main accomplishment was the installation of a reproductive test facility for FP release and transport behavior. Moreover, basic knowledge about the Cs chemisorption behavior was also obtained. In addition to the four research items, a further research item is being considered for deeper interpretation of FP behavior by the analysis of samples outside of the 1F units.
Suzuki, Yoshio; Tatekawa, Takayuki; Kim, G.; Kino, Chiaki; Miyamura, Hiroko; Teshima, Naoya; Hayashi, Sachiko*; Aoyagi, Tetsuo; Takemiya, Hiroshi; Nakajima, Norihiro
Keisan Kogaku Koenkai Rombunshu, 15(2), p.1051 - 1054, 2010/05
We have developed the Atomic Energy Grid InfraStructure (AEGIS) for establishing computational infrastructure for nuclear field. In this R&D we have inherited the knowledge and skills in ITBL Infrastructure developed in the national project ITBL (Information Technology Based Laboratory), which aims at establishment of virtual research environment where supercomputers and data bases are connected by network. Here we have focused on two issues: improvements of safety and usability. For the safety, we have made the authentication mechanism double with both the personal certification and the machine certification. For the usability, we have developed the grid-enabled client API to use grid functions on a user terminal. By those R&Ds, we have successfully contributed to various nuclear researches, such as "full scale 3D vibration simulator for an entire nuclear power plant", "simulation for predicting quake-proof capability of nuclear power plants", and so on.
Sakanaka, Shogo*; Akemoto, Mitsuo*; Aoto, Tomohiro*; Arakawa, Dai*; Asaoka, Seiji*; Enomoto, Atsushi*; Fukuda, Shigeki*; Furukawa, Kazuro*; Furuya, Takaaki*; Haga, Kaiichi*; et al.
Proceedings of 1st International Particle Accelerator Conference (IPAC '10) (Internet), p.2338 - 2340, 2010/05
Future synchrotron light source using a 5-GeV energy recovery linac (ERL) is under proposal by our Japanese collaboration team, and we are conducting R&D efforts for that. We are developing high-brightness DC photocathode guns, two types of cryomodules for both injector and main superconducting (SC) linacs, and 1.3 GHz high CW-power RF sources. We are also constructing the Compact ERL (cERL) for demonstrating the recirculation of low-emittance, high-current beams using above-mentioned critical technologies.
Teshima, Naoya; Aoyagi, Tetsuo; Hashimoto, Kiyoharu*; Manabe, Atsushi*; Yuasa, Fukuko*; Nakajima, Norihiro
JAEA-Data/Code 2009-004, 24 Pages, 2009/06
JAEA-Data-Code-2009-004.pdf:1.65MB
The authentication System Group of J-PARC Information System Group carried out the feasibility study about PKI authentication method that used IC card. Its purpose was that we validated its practical utility to choose an authentication method to adjust a security level desired at the information system of J-PARC. As a target of the feasibility studies, we chose following four validation items. (1) "The EAP-TLS wireless LAN authentication method" (2) "The Web-SSL client authentication method when accessed via SSL-VPN device" (3) "The PKI authentication method that used IC card stored the certificate which issued by NAREGI-CA software. (4) "The PKI authentication method that used Dual card type FeliCa". We established validation point for each validation item, and carried out it. So, we got the results and useful information. This report is that we organized a validation procedure, result and knowledge that we got by feasibility studies.
Suzuki, Yoshio; Nishida, Akemi; Araya, Fumimasa; Kushida, Noriyuki; Akutsu, Taku; Teshima, Naoya; Nakajima, Kohei; Kondo, Makoto; Hayashi, Sachiko; Aoyagi, Tetsuo; et al.
Journal of Power and Energy Systems (Internet), 3(1), p.60 - 71, 2009/00
Center for computational science and e-systems of Japan Atomic Energy Agency is carrying out R&D in the area of extra large-scale simulation technologies for solving nuclear plant structures in its entirety. Specifically, we focus on establishing a virtual plant vibration simulator on inter-connected supercomputers intended for seismic response analysis of a whole nuclear plant. The simulation of a whole plant is a very difficult task because an extremely large dataset must be processed. To overcome this difficulty, we have proposed and implemented a necessary simulation framework and computing platform. The computing platform enables an extra large-scale whole nuclear plant simulation to be carried out on a grid computing platform ITBL-IS and AEGIS. The simulation framework based on the computing platform has been applied to a linear elastic analysis of the reactor pressure vessel and cooling systems of the nuclear research facility, HTTR.
Suzuki, Yoshio; Nakajima, Norihiro; Araya, Fumimasa; Hazama, Osamu; Nishida, Akemi; Kushida, Noriyuki; Akutsu, Taku; Teshima, Naoya; Nakajima, Kohei; Kondo, Makoto; et al.
Proceedings of 16th International Conference on Nuclear Engineering (ICONE-16) (CD-ROM), 9 Pages, 2008/05
Suzuki, Yoshio; Nakajima, Kohei; Kushida, Noriyuki; Kino, Chiaki; Aoyagi, Tetsuo; Nakajima, Norihiro; Iba, Katsuyuki*; Hayashi, Nobuhiko; Ozeki, Takahisa; Totsuka, Toshiyuki; et al.
Fusion Engineering and Design, 83(2-3), p.511 - 515, 2008/04
Times Cited Count：3 Percentile：23.55(Nuclear Science & Technology)In collaboration with the Naka Fusion Institute of Japan Atomic Energy Agency (NFI/JAEA) and the National Institute for Fusion Science of National Institute of Natural Science (NIFS/NINS), Center for Computational Science and E-systems of Japan Atomic Energy Agency (CCSE/JAEA) aims at establishing an integrated framework for experiments and analyses in nuclear fusion research based on the Atomic Energy Grid InfraStructure (AEGIS). AEGIS has been being developed by CCSE/JAEA aiming at providing the infrastructure that enables atomic energy researchers in remote locations to carry out R&D efficiently and collaboratively through the Internet. Toward establishing the integrated framework, we have been applying AEGIS to pre-existing three systems.
Hazama, Osamu; Kushida, Noriyuki; Matsubara, Hitoshi; Nishida, Akemi; Suzuki, Yoshio; Araya, Fumimasa; Aoyagi, Tetsuo; Nakajima, Norihiro; Kondo, Makoto
Proceedings of 9th MpCCI User Forum, p.118 - 124, 2008/00
In order to safely and stably supply energy by nuclear means, structural integrity and design standards of the plant including factors such as aging must be confirmed, and its future conditions must be predicted with high reliability. Although full-scale experimentations are favorable for acquiring necessary information and carrying out investigative studies of the nuclear structures, such experiments are for most cases physically and financially impossible. Our objective is to establish an integrated full-scale simulation framework for simulating and quantitatively investing the vibration behavior of nuclear power plant equipments under earthquakes.
Sasao, Mamiko*; Kusama, Yoshinori; Kawano, Yasunori; Kawahata, Kazuo*; Mase, Atsushi*; Sugie, Tatsuo; Fujita, Takaaki; Fukuda, Takeshi*; Fukuyama, Atsushi*; Sakamoto, Yoshiteru; et al.
Purazuma, Kaku Yugo Gakkai-Shi, 83(9), p.779 - 782, 2007/09
This is a report of highlights from 2007 spring meetings of seven Topical Groups (TG) of International Tokamak Physics Activity (ITPA). In each meeting, high priority issues in physics of International Thermonuclear Experimental Reactor (ITER) and other burning plasma experiments have been discussed and investigated. Twenty-seven scientists from Japan have participated in those meetings. Dates and places of the meetings are shown below. (1) Diagnostics TG: 26-30 March, Princeton (USA), (2) Transport Physics TG: 7-10 May, Lausanne (Switzerland), (3) Confinement Database and Modeling TG: 7-10 May, Lausanne (Switzerland), (4) Edge Pedestal Physics TG: 7-10 May, Garching (Germany) (5) Steady State Operation TG: 9-11 May, Daejeon (South Korea), (6)MHD TG: 21-24 May, San Diego (USA), (7) Scrape-off-layer and Divertor Physics TG: 7-10 May, Garching (Germany).
Minami, Takahiro; Suzuki, Yoshio; Aoyagi, Tetsuo; Ito, Toshinori*; Nakajima, Norihiro
FAPIG, (174), p.31 - 39, 2007/02
The Center for Computational Science and E-systems of the Japan Atomic Energy Agency (CCSE/JAEA) has started a program to construct an international computational infrastructure in atomic energy research field called the AEGIS (Atomic Energy Grid InfraStructure) in April, 2006. The development is based on numerous experiences and technologies acquired from the development of the STA (Seamless Thinking Aid) and the ITBL (Information Technology Based Laboratory) infrastructure software. In this paper, we will introduce two key achievements prior to the AEGIS program: "Interoperable system between UNICORE in Germany and ITBL" which achieves international sharing of computational resources, and the "STARPC Plus" which can construct a compact grid system.
Kushida, Noriyuki; Suzuki, Yoshio; Minami, Takahiro; Aoyagi, Tetsuo; Nakajima, Norihiro
Zen NEC C&C Shisutemu Yuzakai Heisei-19-Nendo Rombunshu (CD-ROM), 10 Pages, 2007/00
Interoperability establishment between two different GRIDs.
Suzuki, Yoshio; Aoyagi, Tetsuo; Tani, Masayuki; Nakajima, Norihiro; Hirayama, Toshio
Genshiryoku eye, 52(10), p.35 - 39, 2006/10
no abstracts in English
Asakura, Nobuyuki; Kato, Takako*; Nakano, Tomohide; Takamura, Shuichi*; Tanabe, Tetsuo*; Iio, Shunji*; Nakajima, Noriyoshi*; Ono, Yasushi*; Ozeki, Takahisa; Takechi, Manabu; et al.
Purazuma, Kaku Yugo Gakkai-Shi, 82(7), p.448 - 450, 2006/07
no abstracts in English
Ninomiya, Hiromasa; Asakura, Nobuyuki; Kato, Takako*; Takamura, Shuichi*; Tanabe, Tetsuo*; Nakano, Tomohide; Iio, Shunji*; Ozeki, Takahisa; Ono, Yasushi*; Sugihara, Masayoshi; et al.
Purazuma, Kaku Yugo Gakkai-Shi, 81(11), p.960 - 961, 2005/11
no abstracts in English
Kawano, Yasunori; Kawahata, Kazuo*; Kusama, Yoshinori; Sasao, Mamiko*; Sugie, Tatsuo; Mase, Atsushi*; Asakura, Nobuyuki; Kato, Takako*; Takamura, Shuichi*; Tanabe, Tetsuo*; et al.
Purazuma, Kaku Yugo Gakkai-Shi, 81(2), p.128 - 130, 2005/02
no abstracts in English
Asakura, Nobuyuki; Iio, Shunji*; Ozeki, Takahisa; Ono, Yasushi*; Kato, Takako*; Kawano, Yasunori; Sugihara, Masayoshi; Takamura, Shuichi*; Tanabe, Tetsuo*; Nakajima, Noriyoshi*; et al.
Purazuma, Kaku Yugo Gakkai-Shi, 80(7), P. 642, 2004/07
no abstracts in English
Nakajima, Norihiro; Kimura, Hideo; Higuchi, Kenji; Aoyagi, Tetsuo; Suzuki, Yoshio; Hirayama, Toshio; Yagawa, Genki
Dai-23-Kai Nihon Shimyureshon Gakkai Taikai Happyo Rombunshu, p.117 - 120, 2004/06
The pablic acceptance of nuclear power plants operations requests information of status for the safety and ease. Previous technology in computational scinece is generarlly carried out the analysis as an uniform structure, although the plants are assembled by thousand of parts. The proposed approach is to develope assembled structural analysis and fluid/heat analyis in assembled structures under the natural and actual environmnet such as daily operation, small quakeing which does not induce shut down procedure, and so on.
