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Journal Articles

Measurements and analyses of the distribution of the radioactivity induced by the secondary neutrons produced by 17-MeV protons in compact cyclotron facility

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:0.03

Journal Articles

Benchmark study of the recent version of the PHITS code

Iwamoto, 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:99.74(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.

Journal Articles

Production and separation of astatine isotopes in the $$^7$$Li + $$^{nat}$$Pb reaction

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:61.38(Chemistry, Analytical)

Production cross sections of astatine isotopes $$^{207-211}$$At in the 29-57 MeV $$^7$$Li induced reaction with $$^{nat}$$Pb target have been measured by $$alpha$$- and $$gamma$$-ray spectrometry. Excitation functions of production cross sections have been compared with a statistical model calculation to study the reaction mechanism of $$^7$$Li + $$^{nat}$$Pb. Considerably small experimental cross sections of $$^{210}$$At and $$^{209}$$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.

Journal Articles

Research and development of full-scale three-dimensional vibration simulator for nuclear plant

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.

Journal Articles

Component-wise meshing approach and evaluation of bonding strategy on the interface of components for assembled finite element analysis of structures

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.

Journal Articles

Structural simulation and modeling for assembly in real space

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.

Journal Articles

A Script generator API for the full-scale three-dimensional vibration simulation of an entire nuclear power plant within AEGIS

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

Journal Articles

Development and application research of vibration simulator for full-scale nuclear power station

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.

Journal Articles

A Large scale simulation for impact and blast loading issues

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.

Journal Articles

Real space simulation with reality modeling for vibration table by an assembly structural analysis

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.

Journal Articles

Proposal of vibration table in an extended world by grid computing technology for assembled structures

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.

Journal Articles

Generation of broadband mid-infrared pulses by noncollinear difference frequency mixing

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:30.22(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$$_{2}$$ 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.

Journal Articles

Selective transition to the closely-lying states Cs(7$$D$$$$_{3/2}$$) and Cs(7$$D$$$$_{5/2}$$) by femtosecond laser pulses

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:31.32(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$$D$$$$_{3/2}$$) and Cs(7$$D$$$$_{5/2}$$) 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$$^3$$ with the delay less than 400 fs.

Journal Articles

Optimal control of ultrafast selection

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:18.84(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 $$rightarrow$$ 7D$$_{J}$$, 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 $$sim$$ 30 % from the simple "Ramsey fringes" experiment.

Oral presentation

For realization of the vibration simulation of the nuclear power plant scale

Nakajima, Norihiro; Yamada, Tomonori; Nakajima, Kohei; Nishida, Akemi; Suzuki, Yoshio; Araya, Fumimasa; Kushida, Noriyuki

no journal, , 

no abstracts in English

Oral presentation

Cerebral methodology based computing for estimating validity of simulation results

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.

Oral presentation

Vibration simulation for component and piping structures of nuclear plants

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.

Oral presentation

Nuclear and radiochemical study of production and utilization of radioactive astatine isotopes using lithium ion beams at the tandem accelerator of JAEA-Tokai

Nishinaka, Ichiro; Yokoyama, Akihiko*; Washiyama, Koshin*; Amano, Ryohei*; Yamada, Norihiro*; Ishiguro, Rika*; Makii, Hiroyuki; Hashimoto, Kazuyuki

no journal, , 

An $$alpha$$ radioactive nuclide $$^{211}$$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 $$^7$$Li+$$^{nat}$$Pb and studied a chemical behavior of carrier-free radioactive astatine isotopes with a dry-chemistry method. Details will be shown in the presentation.

Oral presentation

Research and development in Center of Computational Science and e-Systems, JAEA

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.

Oral presentation

Production of astatine radioisotopes in the $$^7$$Li+$$^{nat}$$Pb reaction and simple chemical separation of astatine

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 $$alpha$$ radioactive nuclide $$^{211}$$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 $$^7$$Li+$$^{nat}$$Pb by $$alpha$$-ray and $$gamma$$-ray spectrometry at the tandem accelerator of JAEA-Tokai. Besides, we developed a simple dry-chemical method for separation of astatine.

28 (Records 1-20 displayed on this page)