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Matsuda, Norihiro; Izumi, Yuichi*; Yamanaka, Yoshiyuki*; Gando, Toshiyuki*; Yamada, Masaaki*; Oishi, Koji*
EPJ Web of Conferences, 153, p.07001_1 - 07001_6, 2017/09
Times Cited Count:0 Percentile:0.03Iwamoto, Yosuke; Sato, Tatsuhiko; Hashimoto, Shintaro; Ogawa, Tatsuhiko; Furuta, Takuya; Abe, Shinichiro; Kai, Takeshi; Matsuda, Norihiro; Hosoyamada, Ryuji*; Niita, Koji*
Journal of Nuclear Science and Technology, 54(5), p.617 - 635, 2017/05
Times Cited Count:83 Percentile:99.73(Nuclear Science & Technology)We performed a benchmark study for 58 cases using the recent version 2.88 of the Particle and Heavy Ion Transport code System (PHITS) in the following fields: particle production cross-sections for nuclear reactions, neutron transport calculations, and electro-magnetic cascade. This paper reports details for 22 cases. In cases of nuclear reactions with energies above 100 MeV and electro-magnetic cascade, overall agreements were found to be satisfactory. On the other hand, PHITS did not reproduce the experimental data for an incident proton energy below 100 MeV, because the intranuclear cascade model INCL4.6 in PHITS is not suitable for the low-energy region. For proton incident reactions over 100 MeV, PHITS did not reproduce fission product yields due to the problem of high-energy fission process in the evaporation model GEM. To overcome these inaccuracies, we are planning to incorporate a high-energy version of the evaluated nuclear data library JENDL-4.0/HE, and so on.
Nishinaka, Ichiro; Yokoyama, Akihiko*; Washiyama, Koshin*; Maeda, Eita*; Watanabe, Shigeki; Hashimoto, Kazuyuki; Ishioka, Noriko; Makii, Hiroyuki; Toyoshima, Atsushi; Yamada, Norihiro*; et al.
Journal of Radioanalytical and Nuclear Chemistry, 304(3), p.1077 - 1083, 2015/06
Times Cited Count:9 Percentile:61(Chemistry, Analytical)Production cross sections of astatine isotopes At in the 29-57 MeV Li induced reaction with Pb target have been measured by - and -ray spectrometry. Excitation functions of production cross sections have been compared with a statistical model calculation to study the reaction mechanism of Li + Pb. Considerably small experimental cross sections of At and At compared with the calculation were clearly observed at incident energies higher than 44 MeV, indicating that the effects of breakup reaction play a role. A chemical separation of astatine from an irradiated lead target has been studied with a dry-distillation method. A complementary way to produce astatine isotopes has been developed.
Nishida, Akemi; Suzuki, Yoshio; Yamada, Tomonori; Kino, Chiaki; Uzawa, Ken*; Miyamura, Hiroko; Kawamura, Takuma; Takemiya, Hiroshi; Nakajima, Norihiro
RIST News, (54), p.33 - 37, 2013/01
Nuclear plants are complicated and huge structures and consist of a large number of parts. To simulate the behavior of such a complicated huge structure, it becomes important the viewpoint as a general system including pre-post-processing. Therefore, the CCSE proposed an approach for assembly structure analysis and implemented a framework of a full-scale 3D vibration simulator for an entire nuclear plant. Until now, we performed numerical experiments using the data of a building and equipment of HTTR, Oarai R&D Center, JAEA, and demonstrated that earthquake response simulation of large-scale structure as an entire nuclear plant was possible so far. In this report, the framework of the full-scale 3D vibration simulator, the assembly structure analysis approach and visualization technology for an evaluation of the results are shown. And finally, an example of application of the simulator for probabilistic risk assessment, PRA, started from 2011, is shown.
Yamada, Tomonori; Kushida, Noriyuki; Araya, Fumimasa; Nishida, Akemi; Nakajima, Norihiro
Key Engineering Materials, 452-453, p.701 - 704, 2011/01
The paper describes a component-wise meshing approach and bonding strategy on the interface of components. In order to assemble component-wise meshes, the penalty method is introduced not only to constrain the displacements, but also to introduce classical spring connection on the joint interface. The convergence performance of an iterative solver with penalty method is investigated and the detailed component-wise distributed computation scheme is described with numerical examples.
Nakajima, Norihiro; Nishida, Akemi; Suzuki, Yoshio; Yamada, Tomonori; Takemiya, Hiroshi; Iyoku, Tatsuo
Proceedings of Joint International Conference of 7th Supercomputing in Nuclear Application and 3rd Monte Carlo (SNA + MC 2010) (USB Flash Drive), 4 Pages, 2010/10
FIESTA is a large scale simulation, which concerns a simulation space to bring real world in digital space, such as so named either virtual reality or virtual facility. In order to establish a huge and complex object like nuclear facilities of a real world, there are lack of methodology and technology for reproducing facilities in digital space. FIESTA attempts to realize an assembly structural analysis for supplying one of the methodologies to reproduce facilities in digital space. The first attempt of the structural analysis for assembly is accomplished by finite element analysis by integrating parts of facilities. Since the structural analysis for assembly requests massive calculation, parallel and distributed computing was applied for the computational environment. The structural analysis for assembly by finite element method is confirmed to be able to analyze a huge and complex facility and show results of numerical experiment by applying to a test reactor driven by JAEA.
Kim, G.; Suzuki, Yoshio; Teshima, Naoya; Nishida, Akemi; Yamada, Tomonori; Araya, Fumimasa; Takemiya, Hiroshi; Nakajima, Norihiro; Kondo, Makoto
Proceedings of 1st International Conference on Parallel, Distributed and Grid Computing for Engineering (PARENG 2009) (CD-ROM), 12 Pages, 2009/04
Nishida, Akemi; Araya, Fumimasa; Yamada, Tomonori; Kushida, Noriyuki; Takemiya, Hiroshi; Nakajima, Norihiro
Anzen Kenkyu Foramu 2009 Shiryoshu, p.25 - 29, 2009/02
The development of a vibration simulator has been planned for used in a full-scale nuclear power station; this simulator will implement the latest computational technologies and will allow comparisons to be made among the conventional spring-mass models and the actually observed data obtained from experiment and practice. This simulator will be used for evaluating the conservativeness of conventional models and the fragility of components through a seismic PSA (probabilistic safety assessment). This simulator will be used for analyzing the seismic responses of the entire nuclear facility by modeling each component independently. The numerical capability of the simulator has already been confirmed; presently, the accuracy of the dynamic response results is being investigated by means of a comparison with the recorded data of an actual plant system.
Nakajima, Norihiro; Araya, Fumimasa; Nishida, Akemi; Suzuki, Yoshio; Ida, Masato; Yamada, Tomonori; Kushida, Noriyuki; Kim, G.; Kino, Chiaki; Takemiya, Hiroshi
Proceedings of International Symposium on Structures under Earthquake, Impact, and Blast Loading 2008, p.119 - 123, 2008/10
Japan is so said an energy consumption country of the fourth place world, but the energy resources such as petroleum, the natural gas are poor and depend on import for the most, and stable supply becomes a big problem. For the greenhouse gas restraint, the promotion of the energy saving is featured. A nuclear power plant for commerce in Japan has been started in 1966. The supply occupies about 30 percent of the now Japanese electricity generating. Due to the nature of Japan, earthquake proof is an important subject for social infrastructure operation. To encourage its proofing, many approaches have been applied into many infrastructures, not only computational approach. A computational science approach for earthquake proof is suggested with FIESTA(Finite Element Structural analysis for Assembly), a large scale simulation. A methodology is discussed from the point of view of impact and blast loadings. Examples of loadings in the nuclear engineering are introduced.
Nakajima, Norihiro; Araya, Fumimasa; Nishida, Akemi; Suzuki, Yoshio; Kushida, Noriyuki; Yamada, Tomonori
Dai-57-Kai Riron Oyo Rikigaku Koenkai Koen Rombunshu, p.33 - 35, 2008/06
It has been disciplined to realize a simulation space, which can emulate real world in digital space, such as so named either virtual reality or virtual facility. In this paper, it is realized an assembly structural analysis for supplying one of the methodology to reproduce facilities in digital space. The first attempt of the assembly structural analysis is accomplished by finite element analysis by integrating parts of facilities. Since the assembly structural analysis requests massive calculation, grid computing was applied for the computational resource.
Yamada, Tomonori; Araya, Fumimasa; Nishida, Akemi; Kushida, Noriyuki; Nakajima, Norihiro
Theoretical and Applied Mechanics Japan, 57, p.81 - 87, 2008/00
We realize a vibration table in an extended world for simulation, which is capable of emulating the real world's earthquake in digital space and brings concurrent experiments between real and digital one. In this paper, a methodology for reproducing facilities in an extended world is proposed through analysis of assembled structures, as well as introduction of the computing framework used.
Sugita, Akihiro; Yokoyama, Keiichi; Yamada, Hidetaka; Inoue, Norihiro*; Aoyama, Makoto; Yamakawa, Koichi
Japanese Journal of Applied Physics, Part 1, 46(1), p.226 - 228, 2007/01
Times Cited Count:7 Percentile:30.15(Physics, Applied)Generation of broadband mid-infrared (MIR) laser pulses by difference frequency mixing (DFM) is reported. Two-color femtosecond pulses from a Ti: Sapphire laser system is mixed in an AgGaS crystal utilizing a noncollinear phase matching scheme. The relative bandwidth of the generated MIR pulse has been measured to be 23 % to the central frequency, the broadest in DFM-based MIR sources reported so far. It is found that the type-I crystal can give broader phase matching range of spectrum than the type-II crystal within this scheme.
Yamada, Hidetaka; Yokoyama, Keiichi; Teranishi, Yoshiaki*; Sugita, Akihiro; Shirai, Toshizo*; Aoyama, Makoto; Akahane, Yutaka; Inoue, Norihiro*; Ueda, Hideki*; Yamakawa, Koichi; et al.
Physical Review A, 72(6), p.063404_1 - 063404_5, 2005/12
Times Cited Count:6 Percentile:31.26(Optics)A demonstration of coherent quantum control for ultrafast precise selection of closely-lying states is reported. A phase-locked pair of femtosecond laser pulses is generated through a pulse shaper to excite the ground-state cesium atom to the Cs(7) and Cs(7) states by two-photon absorption. The excited state population is measured by detecting fluorescence from each spin-orbit state. By controlling the phase-difference of the pulse pair, an ultrafast precise selection is accomplished. The contrast ratio of the maximal to minimal selection ratio exceeds 10 with the delay less than 400 fs.
Yokoyama, Keiichi; Teranishi, Yoshiaki; Toya, Yukio; Shirai, Toshizo; Fukuda, Yuji; Aoyama, Makoto; Akahane, Yutaka; Inoue, Norihiro*; Ueda, Hideki; Yamakawa, Koichi; et al.
Journal of Chemical Physics, 120(20), p.9446 - 9449, 2004/05
Times Cited Count:6 Percentile:18.8(Chemistry, Physical)Optimal laser control for ultrafast selection of closely-lying excited states, whose energy separation is smaller than the laser bandwidth, is reported on the two-photon transition of atomic cesium; Cs(6S 7D, J = 5/2 and 3/2). Selective excitation was carried out by pulse shaping of ultrashort laser pulses which were adaptively modulated in a closed-loop learning system handling eight parameters representing the electric field. Two-color fluorescence from the respective excited states was monitored to measure the selectivity. The fitness used in the learning algorithm was evaluated from the ratio of the fluorescence yield. After fifty generations, a pair of nearly transform-limitted pulses were obtained as an optimal pulse shape, proving the effectiveness of "Ramsey fringes" mechanism. The contrast of the selection ratio was improved by 30 % from the simple "Ramsey fringes" experiment.
Nakajima, Norihiro; Yamada, Tomonori; Nakajima, Kohei; Nishida, Akemi; Suzuki, Yoshio; Araya, Fumimasa; Kushida, Noriyuki
no journal, ,
no abstracts in English
Suzuki, Yoshio; Nishida, Akemi; Yamada, Tomonori; Araya, Fumimasa; Hayashi, Sachiko; Nakajima, Norihiro; Hirayama, Toshio
no journal, ,
Our challenge is to estimate the validity of simulation results by establishing "Cerebral Methodology Based Computing (CMC)". The estimation of the validity is indispensable to accurately predict phenomena by using simulation. It is difficult to estimate the validity from a single simulation because the simulation contains uncertainties and ambiguities. We have proposed CMC as the computing methodology which enables us to estimate the validity of results with both deductive and inductive approaches, similar to the human thinking process. To realize CMC, we have constructed the system which enables us to execute both deductive simulations and inductive simulations, and then combine results of those simulations in an integration process. We have applied the system to a thermal displacement analysis of a nuclear power plant and confirmed the usefulness of the system.
Nishida, Akemi; Yamada, Tomonori; Kushida, Noriyuki; Araya, Fumimasa; Takemiya, Hiroshi; Nakajima, Norihiro
no journal, ,
We regarded component and piping structures of nuclear plants as a structure body by the accumulation of the part, and proposed an assembly structure analysis method as means to analyze the entire by assembling the data of the part unit. We applied this technique to finite element analysis and built a trial simulation system on parallel and distributed computer environment AEGIS in JAEA. Under the cooperation with department of HTTR, Oarai Research and Development Center, we carried out fundamental inspections by using some real plant data and confirmed the validity of the solution.
Nishinaka, Ichiro; Yokoyama, Akihiko*; Washiyama, Koshin*; Amano, Ryohei*; Yamada, Norihiro*; Ishiguro, Rika*; Makii, Hiroyuki; Hashimoto, Kazuyuki
no journal, ,
An radioactive nuclide At is a prospective candidate for utilization in targeted alpha radiotherapy. We have started nuclear and radiochemical study of production and utilization of radioactive astatine isotopes using lithium ion beams at the tandem accelerator of JAEA-Tokai. We determined the excitation functions of astatine isotopes in the reaction of 29-48 MeV Li+Pb and studied a chemical behavior of carrier-free radioactive astatine isotopes with a dry-chemistry method. Details will be shown in the presentation.
Nakajima, Norihiro; Kawamura, Takuma; Takemiya, Hiroshi; Uzawa, Ken; Idomura, Yasuhiro; Yamada, Susumu
no journal, ,
In the International Conference SC '11 (The Annual Conference for High Performance Computing, Networking, Storage and Analysis), it is exhibited and presented as the achievement of research and development in Center of Computational Science and e-Systems of JAEA, that is, in structural analyses, quake-proof analyses, materials simulations, computer science in nuclear engineering, and applications in nuclear science.
Nishinaka, Ichiro; Yokoyama, Akihiko*; Washiyama, Koshin*; Amano, Ryohei*; Ri, Keiko*; Yamada, Norihiro*; Ishiguro, Rika*; Maeda, Eita*; Makii, Hiroyuki; Hashimoto, Kazuyuki; et al.
no journal, ,
We have started to study production and utilization of an radioactive nuclide At which is a prospective candidate for targeted alpha radiotherapy. We determined production cross sections of astatine radioisotopes in the reaction of 29-48 MeV Li+Pb by -ray and -ray spectrometry at the tandem accelerator of JAEA-Tokai. Besides, we developed a simple dry-chemical method for separation of astatine.