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Yamamoto, Keiichi; Takeuchi, Tomoaki; Hayashi, Takayasu*; Kosuge, Fumiaki*; Tsuchiya, Kunihiko
JAEA-Testing 2016-002, 25 Pages, 2016/11
JAEA-Testing-2016-002.pdf:4.97MB
Development of the reactor measurement system has been carried out to obtain the real-time in-core nuclear and thermal information, where the quantitative measurement of brightness of Cherenkov light was investigated. The system would be applied as a monitoring system in severe accidents and for the advanced operation management technology in existing LWRs. This report summarized the modification of Cherenkov light estimation system described JAEA-Testing 2015-001 and the result of the burn-up evaluation by Cherenkov light image emitted from spent fuel elements of LWRs with the modified system.
Yamamoto, Keiichi; Takeuchi, Tomoaki; Hayashi, Takayasu*; Kosuge, Fumiaki*; Sano, Tadafumi*; Tsuchiya, Kunihiko
JAEA-Testing 2015-001, 25 Pages, 2015/11
JAEA-Testing-2015-001.pdf:3.52MB
Development of the reactor measurement system was started to obtain the real-time in-core nuclear and thermal information, where the quantitative measurement of brightness of Cherenkov light was investigated. This report was summarized the results of design and trial fabrication of the Cherenkov light estimation system from thermal power evaluation from Cherenkov light image emitted from the fuel elements. The developed Cherenkov light estimation system was verified with the Cherenkov light image emitted from the fuels in the core of Kyoto University Research Reactor (KUR). From the results, it is necessary to improve the observation method of Cherenkov light in the reactor and the evaluation method of the brightness of Cherenkov light. In future, the system will be applied for the evaluation of burn-up of spent fuels from the Cherenkov light emitted from the spent fuel assemblies in LWRs.
Mikami, Satoshi; Matsuda, Norihiro; Ando, Masaki; Kinase, Sakae; Kitano, Mitsuaki; Kawase, Keiichi; Matsumoto, Shinichiro; Yamamoto, Hideaki; Saito, Kimiaki
Radioisotopes, 64(9), p.589 - 607, 2015/09
This article presents the features of regional distributions and temporal changes in air dose rate and radionuclide deposition densities in Fukushima on the basis of analyses on large-scale environmental monitoring results using diverse methods. The continuity of decontamination effects is discussed according to repeated monitoring data after the decontamination model project. Further, some examples are shown on the projection of air dose rates together with the ecological half lives for different land uses.
Takeuchi, Tomoaki; Yamamoto, Keiichi; Otsuka, Noriaki; Shibata, Hiroshi; Shibata, Akira; Takemoto, Noriyuki; Tsuchiya, Kunihiko; Sano, Tadafumi*; Unesaki, Hironobu*; Fujihara, Yasuyuki*; et al.
KURRI Progress Report 2014, P. 108, 2015/07
Investigation of a relation between output power and brightness of Cherenkov light of a specific fuel element at KUR by a CCD camera was performed due to a development of a real-time in-core measurement technique using Cherenkov light. The results indicate that the inhomogeneous distribution of output power and the shadow of the control-rod guide tubes and the other irradiation equipment have significant effects on the brightness of the Cherenkov light. These effects could be suppressed by using a number of cameras located at various positions.
SGo, Shintaro*; Ideguchi, Eiji*; Yokoyama, Rin*; Kobayashi, Motoki*; Kisamori, Keiichi*; Takaki, Motonobu*; Miya, Hiroyuki*; Ota, Shinsuke*; Michimasa, Shinichiro*; Shimoura, Susumu*; et al.
JPS Conference Proceedings (Internet), 6, p.030005_1 - 030005_4, 2015/06
Yamamoto, Keiichi; Takeuchi, Tomoaki; Sano, Tadafumi*; Homma, Ryohei*; Kimura, Nobuaki; Otsuka, Noriaki; Kosuge, Fumiaki*; Nakajima, Ken*; Tsuchiya, Kunihiko
JAEA-Technology 2014-028, 56 Pages, 2015/01
JAEA-Technology-2014-028.pdf:9.23MB
Development of the reactor measurement system was started to obtain real-time in-core nuclear and thermal information, where the quantity measurement of brightness of Cherenkov light was applied. The system would be applied as monitoring system in severe accidents and for advanced operation management technology in existing LWRs. In this report, the calculation and the observation results were summarized about the quantity of the Cherenkov light caused by the 
and 
ray emitted from the fuels in the core of Kyoto University Research Reactor.
Otsuka, Noriaki; Takeuchi, Tomoaki; Yamamoto, Keiichi; Shibata, Akira; Kimura, Nobuaki; Takemoto, Noriyuki; Tanimoto, Masataka; Tsuchiya, Kunihiko; Sano, Tadafumi*; Unesaki, Hironobu*; et al.
KURRI Progress Report 2013, P. 215, 2014/10
Investigation of a relation between reactor power and brightness of Cherenkov light at Kyoto University Research reactor (KUR) by a CCD camera was performed due to a development of a real-time in-core measurement technique using Cherenkov light. Analyzing the brightness value of individual RGB color component at each pixel, some of the G and B brightness values reached the maximum value of 8-bit binary number, i.e. 255, above about 2-3 MW. Therefore, we corrected the G and B brightness values by the R signals whose brightness value did not saturate even at 5 MW, the maximum reactor power of KUR. Then, the total brightness value was in proportion to the reactor power after the correction. These results indicate the reactor power can be estimated by the observation of Cherenkov light.
Takahiro, Katsumi*; Oizumi, Shinnosuke*; Morimoto, Keiichi*; Kawatsura, Kiyoshi*; Isshiki, Toshiyuki*; Nishio, Koji*; Nagata, Shinji*; Yamamoto, Shunya; Narumi, Kazumasa; Naramoto, Hiroshi*
Applied Surface Science, 256(4), p.1061 - 1064, 2009/11
Times Cited Count：8 Percentile：35.82(Chemistry, Physical)Wakai, Eiichi; Otsuka, Hideo*; Matsukawa, Shingo; Furuya, Kazuyuki*; Tanigawa, Hiroyasu; Oka, Keiichiro*; Onuki, Somei*; Yamamoto, Toshio*; Takada, Fumiki; Jitsukawa, Shiro
Fusion Engineering and Design, 81(8-14), p.1077 - 1084, 2006/02
Times Cited Count：11 Percentile：59.56(Nuclear Science & Technology)no abstracts in English
C in JMTRWakai, Eiichi; Jitsukawa, Shiro; Tomita, Hideki*; Furuya, Kazuyuki; Sato, Michitaka*; Oka, Keiichiro*; Tanaka, Teruyuki*; Takada, Fumiki; Yamamoto, Toshio*; Kato, Yoshiaki; et al.
Journal of Nuclear Materials, 343(1-3), p.285 - 296, 2005/08
Times Cited Count：51 Percentile：94.20(Materials Science, Multidisciplinary)The dependence of helium production on radiation-hardening and -embrittlement has been examined in a reduced-activation martensitic F82H steel doped with 
B, 
B and B+B irradiated at 250C to 2.2 dpa. The total amounts of doping boron were about 60 massppm. The range of He concentration produced in the specimens was from about 5 to about 300 appm. Tensile and fracture toughness tests were performed after neutron irradiation. 50 MeV-He
irradiation was also performed to implant about 85 appm He atoms at 120C by AVF cyclotron to 0.03 dpa, and small punch testing was performed to obtain DBTT. Radiation-hardening of the neutron-irradiated specimens increased slightly with increasing He production. The 100 MPam
DBTT for the F82H+B, F82H+B+B, and F82H+B were 40, 110, and 155C, respectively. The shifts of DBTT due to He production were evaluated as about 70C by 150 appmHe and 115C by 300 appmHe. The DBTT shift in the small punch testing was evaluated as 50C.
Wakai, Eiichi; Kikuchi, Kenji; Yamamoto, Shunya; Aruga, Takeo; Ando, Masami; Tanigawa, Hiroyasu; Taguchi, Tomitsugu; Sawai, Tomotsugu; Oka, Keiichiro*; Onuki, Somei*
Journal of Nuclear Materials, 318, p.267 - 273, 2003/05
Times Cited Count：74 Percentile：96.90(Materials Science, Multidisciplinary)no abstracts in English
Yamamoto, Keiichi*; Yoshida, Kiyoshi
JAERI-M 93-079, 29 Pages, 1993/03
no abstracts in English
Yamamoto, Keiichi*; Yoshida, Kiyoshi; Yasukawa, Yukio*; Tsukamoto, Hideo*; Sasaki, Takashi*; Okuno, Kiyoshi; Nishi, Masataka; Koizumi, Norikiyo; Isono, Takaaki; Sugimoto, Makoto; et al.
Proc. of the 17th Symp. on Fusion Technology, 0, p.971 - 975, 1993/00
no abstracts in English
-FeSi and SiAkutsu, Keiichi*; Hara, Yoshiaki*; Nakaoka, Kanichiro*; Yamamoto, Hiroyuki
no journal, ,
Near-infrared photoluminescence of eutectic mixture of -FeSi and Si has been investigated.
Otsuka, Noriaki; Yamamoto, Keiichi; Takeuchi, Tomoaki; Kimura, Nobuaki; Matsui, Yoshinori; Tsuchiya, Kunihiko; Sano, Tadafumi*; Nakajima, Ken*; Homma, Ryohei*
no journal, ,
no abstracts in English
Yamamoto, Keiichi; Takeuchi, Tomoaki; Otsuka, Noriaki; Tsuchiya, Kunihiko; Sano, Tadafumi*; Nakajima, Ken*; Hayashi, Takayasu*; Kosuge, Fumiaki*
no journal, ,
no abstracts in English
Tanaka, Kenichi*; Fukahori, Tokio; Yamamoto, Masahiro; Sato, Tomonori; Motooka, Takafumi; Okumura, Keisuke; Shibata, Keiichi; Iwamoto, Nobuyuki
no journal, ,
The meaning and plan on development of standard and fundamental databases for material compositions and activation cross sections are introduced. Those database is important for estimation of radioactive nuclide production, which is necessary for safety management and waste estimation for disusing procedure of nuclear plants.
Takahiro, Katsumi*; Morimoto, Keiichi*; Yasuda, Kenji*; Kawaguchi, Kazuhiro; Nagata, Shinji*; Yamamoto, Shunya; Narumi, Kazumasa; Naramoto, Hiroshi*
no journal, ,
no abstracts in English
Tsuchiya, Kunihiko; Takeuchi, Tomoaki; Otsuka, Noriaki; Shibata, Hiroshi; Nakano, Hiroko; Ishida, Takuya; Uehara, Toshiaki; Yamamoto, Keiichi; Saito, Takashi; Nakamura, Jinichi; et al.
no journal, ,
no abstracts in English
