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ultrathin films on van der Waals ferromagnet CrSiTe
Kato, Takemi*; Sugawara, Katsuaki*; Ito, Naohiro*; Yamauchi, Kunihiko*; Sato, Takumi*; Oguchi, Tamio*; Takahashi, Takashi*; Shiomi, Yuki*; Saito, Eiji; Sato, Takafumi*
Physical Review Materials (Internet), 4(8), p.084202_1 - 084202_6, 2020/08
Times Cited Count：4 Percentile：23.49(Materials Science, Multidisciplinary) and CrGeTeIto, Naohiro*; Kikkawa, Takashi*; Barker, J.*; Hirobe, Daichi*; Shiomi, Yuki*; Saito, Eiji
Physical Review B, 100(6), p.060402_1 - 060402_6, 2019/08
Times Cited Count：36 Percentile：87.87(Materials Science, Multidisciplinary)Ishizawa, Akihiro*; Idomura, Yasuhiro; Imadera, Kenji*; Kasuya, Naohiro*; Kanno, Ryutaro*; Satake, Shinsuke*; Tatsuno, Tomoya*; Nakata, Motoki*; Nunami, Masanori*; Maeyama, Shinya*; et al.
Purazuma, Kaku Yugo Gakkai-Shi, 92(3), p.157 - 210, 2016/03
The high-performance computer system Helios which is located at The Computational Simulation Centre (CSC) in The International Fusion Energy Research Centre (IFERC) started its operation in January 2012 under the Broader Approach (BA) agreement between Japan and the EU. The Helios system has been used for magnetised fusion related simulation studies in the EU and Japan and has kept high average usage rate. As a result, the Helios system has contributed to many research products in a wide range of research areas from core plasma physics to reactor material and reactor engineering. This project review gives a short catalogue of domestic simulation research projects. First, we outline the IFERC-CSC project. After that, shown are objectives of the research projects, numerical schemes used in simulation codes, obtained results and necessary computations in future.
Ito, Kimitaka*; Ito, Sanae*; Kamiya, Kensaku; Kasuya, Naohiro*
Plasma Physics and Controlled Fusion, 57(7), p.075008_1 - 075008_7, 2015/07
Times Cited Count：19 Percentile：69.72(Physics, Fluids & Plasmas)The solitary radial electric field in the edge of toroidal plasma is studied based on the electric field bifurcation model. Results are applied to tokamak and helical plasmas, and the dependence of the electric field structure on the plasma parameters and geometrical factors is analyzed. The order of magnitude estimate for tokamak plasma is not far from experimental observations. It is shown that, in helical plasmas, the height of electric field structure is reduced substantially owing to the ripple particle transport, while the width is influenced less. The implications of the results for the limit of achievable gradient in the H-mode pedestal are also discussed.
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：78.21(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.
Kurihara, Osamu; Hato, Shinji; Kanai, Katsuta; Takada, Chie; Takasaki, Koji; Ito, Kimio; Ikeda, Hiroshi*; Oeda, Mikihiro*; Kurosawa, Naohiro*; Fukutsu, Kumiko*; et al.
Journal of Nuclear Science and Technology, 44(10), p.1337 - 1346, 2007/10
Times Cited Count：0 Percentile：0.01(Nuclear Science & Technology)In the case of internal contamination of radionuclides, it is necessary to perform internal dose assessment for radiation protection. For this purpose, the ICRP has given the dose coefficients and the retention and excretion rates for various radionuclides. However, these dosimetric quantities are calculated only in typical conditions, therefore, are not necessarily covered enough in the case of dose assessment in which specific information on the incident or/and individual biokinetic characteristics should be taken into account retrospectively. This paper describes a developed PC-based package of software REIDAC to meet the needs in retrospective dose assessment. REIDAC was verified by comparisons with dosimetric quantities given on the ICRP publications and several examples of practical use were also shown.
Ito, Hisayoshi; Hayakawa, Naohiro; Nashiyama, Isamu*; *
Journal of Applied Physics, 66(9), p.4529 - 4531, 1989/11
Times Cited Count：119 Percentile：97.34(Physics, Applied)no abstracts in English
Ito, Hisayoshi; Hayakawa, Naohiro; Nashiyama, Isamu*; *
JAERI-M 89-094, 13 Pages, 1989/07
no abstracts in English
Sato, Masuo*; Fukawa, Naohiro*; Tamaoki, Tetsuo*; Takahashi, Hideji*; Ito, Atsushi*; Yoshida, Megumi*; Sonoda, Yukio*; Yamamoto, Kazuhiko*; Maruyama, Fumi*
PNC TJ9164 89-003, 200 Pages, 1989/03
In nuclear power plant, we need to realize the computerization for the management of the plant operation and maintenance. Especially, in a periodic inspection, lots of works are concentrated. A great deal of man power is required for examining the permission of works, publishing the component isolation tags and making or revising the documents to control the schedules. Recently, in Light Water Reactor, a lot or computerization systems are developed. We design the plant management system in consideration of the characteristics of a Fast Breeder Reactor. We embody the softwear methods and hardwear systems widely to systematize the plant management technology that is accumulated at the experimental reactor JOYO. We can expect an economization and an inprovment of realiability and efficiency of the plant management.
Ito, Hisayoshi; Yoshikawa, Masahito; Hayakawa, Naohiro; *; Nashiyama, Isamu*
EIM-88-120, p.25 - 34, 1988/12
no abstracts in English
Sato, Masuo*; Fukawa, Naohiro*; Tamaoki, Tetsuo*; Iwashita, Tsuyoshi*; Ito, Atsushi*; Sekiguchi, Mineo*; Yamanaka, Toshikatsu*; Yoshida, Megumi*; Maruyama, Fumi*; Yamamoto, Kazuhiko*
PNC TJ9164 88-007, 96 Pages, 1988/11
The automatic reactor operation syste for JOYO is evaluated. In JOYO, by realizing the automatic operation of control rod, the reduction of the operator's load will be performed, and by improving the man-machine interface, the operability will be also improved, Still, in order to improve the reliability and safety of operator, following items are evaluated. In these evaluations, two kinds of automatic reactor operation systems are considered, one is limited to a control rod operation and the other is to an overall plant operation with steam generators. (1)Configuration of the automatic control rod operation system and the automatic plant operation system. (2)Control algorithm by using the knowledge engineering. (3)Methods of the man-machine interface and the operation against emergency conditions. (4)Scope of modification of the present control rod drive system and central control panels. And, the problems which are necessary to be solved to implement this system, are evaluated. Basic configuration of the automatic control rods operation system and the automatic plant operation system are established, and it is ascertained that the present control rod drive system will be useful to the control rod position control to realize the automatic control rod operation without any modification of the control rod drive mechanism.
Makuuchi, Keizo; Katakai, Akio; Ito, Hiroshi; Hayakawa, Naohiro; Araki, Kunio
Shikizai Kyokai-Shi, 56(6), p.381 - 388, 1983/00
no abstracts in English
Kinase, Sakae; Takahashi, Tomoyuki*; Sato, Satoshi; Saito, Kimiaki; Kurosawa, Naohiro*; Ryufuku, Susumu*; Hayashi, Hiroko*; Ishibashi, Kazufusa*
no journal, ,
no abstracts in English
Sato, Satoshi; Kinase, Sakae; Saito, Kimiaki; Takahashi, Tomoyuki*; Kurosawa, Naohiro*; Ryufuku, Susumu*; Hayashi, Hiroko*; Ishibashi, Kazufusa*; Sakamoto, Ryuichi*; Nemoto, Hisashi*
no journal, ,
no abstracts in English
Sato, Satoshi; Kinase, Sakae; Saito, Kimiaki; Takahashi, Tomoyuki*; Kanno, Mitsuhiro*; Hayashi, Hiroko*; Ishibashi, Kazufusa*; Kurosawa, Naohiro*; Sakamoto, Ryuichi*; Nemoto, Hisashi*
no journal, ,
no abstracts in English
Ryufuku, Susumu*; Ishibashi, Kazufusa*; Hayashi, Hiroko*; Kurosawa, Naohiro*; Sato, Satoshi; Kinase, Sakae; Saito, Kimiaki; Takahashi, Tomoyuki*
no journal, ,
no abstracts in English
SR studies on PrRhZn
Higemoto, Wataru; Ito, Takashi; Nagasawa, Naohiro*; Onimaru, Takahiro*; Takabatake, Toshiro*
no journal, ,
In caged structural compound PrRhZn, superconductivity and other unknown phase transition occur at the same temperature 0.06K. This phase transition is speculated as quadrupole phase transition. However, no any microscopic study is carried out up to now and detail of the phase transition is not known at all. We have studied quadrupole ordering and superconductivity in PrRhZn by using muon spin relaxation method at J-PARC muon science facility. As a result, we have not observed any significant change of the signal above and below phase transition temperature. This fact indicate the no magnetic phase transition occur and support the quadrupole phase transition. In addition, no trace of an unconventional superconductivity was detected in our measurements. In the presentation, we will mention detail of the measurements.
Chigira, Tomoyuki*; Shiina, Tatsuo*; Saito, Hayato*; Manago, Naohiro*; Kuze, Hiroaki*; Hanyu, Toshinori; Kanayama, Fumihiko; Fukushima, Mineo
no journal, ,
The compact Raman Lidar is developed for the atmosphere measurement under nuclear environment, in which radiation ionize the water vapor and generate the water-cluster. In this study, the Raman lidar throws the NUV-beam of 349 nm and detects the backscattering echoes of water-Raman (396 nm) and the water-vapor-Raman (400 nm). Am-241 of 9 MBq was used for the radiation source. The results showed that the water-Raman increased and the water-vapor-Raman decreased under the nuclear environment. Its ratio becomes 3 times. It is well coincide with the estimation. The radius of water cluster was estimated 200 nm by the experiment.
Shiina, Tatsuo*; Chigira, Tomoyuki*; Saito, Hayato*; Manago, Naohiro*; Kuze, Hiroaki*; Hanyu, Toshinori; Kanayama, Fumihiko; Fukushima, Mineo
no journal, ,
Shiina, Tatsuo*; Saito, Hayato*; Manago, Naohiro*; Kuze, Hiroaki*; Hanyu, Toshinori; Kanayama, Fumihiko; Fukushima, Mineo
no journal, ,
no abstracts in English
