Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Tonoike, Kotaro; Okubo, Kiyoshi; Takada, Tomoyuki*
Proceedings of International Conference on Nuclear Criticality Safety (ICNC 2015) (DVD-ROM), p.292 - 300, 2015/09
The damaged Unit 1-3 reactors of the Fukushima Daiichi Nuclear Power Station may contain fuel debris of a significant amount that is in a form of molten-core-concrete-interaction (MCCI) product with porous structure. Such low density MCCI product including fissile material is a great concern for its criticality control, especially under submerged condition, due to its fairly good neutron moderation. This report shows computation results of basic criticality characteristics of the MCCI product, which will facilitate criticality risk assessments during decommissioning of the reactors. The results imply that water bound in concrete may raise the risk from the viewpoints of possibility of criticality events and of effectiveness of mitigation measures such as neutron poison injection into coolant water.
Shinohara, Masanori; Motegi, Toshihiro; Saito, Kenji; Haga, Hiroyuki; Sasaki, Shinji; Katsuyama, Kozo; Takada, Kiyoshi*; Higashimura, Keisuke*; Fujii, Junichi*; Ukai, Takayuki*; et al.
JAEA-Technology 2012-032, 29 Pages, 2012/11
JAEA-Technology-2012-032.pdf:6.57MB
An event, in which one of WRMs were disabled to detect the neutron flux in the reactor core, occurred during the period of reactor shut down of HTTR in March, 2010. The actual life time of WRM was unexpectedly shorter than the past developed life time. Investigation of the cause of the outage of WRM toward the recovery of the life time up to the past developed life is one of the issues to develop the technology basis of HTGR. Then, two experimental investigations were carried out to reveal the cause of the malfunction by specifying the damaged part causing the event in the WRM. One is an experiment using a mock-up sample test which strength degradation on assembly accuracy and heat cycle to specify the damaged part in the WRM. The other is a destructive test in FMF to specify the damaged part in the WRM. This report summarized the results of the destructive test and the experimental investigation using the mock-up to reveal the cause of malfunction of WRM.
Suyama, Kenya; Mochizuki, Hiroki*; Takada, Tomoyuki*; Ryufuku, Susumu*; Okuno, Hiroshi; Murazaki, Minoru; Okubo, Kiyoshi
JAEA-Data/Code 2009-002, 124 Pages, 2009/05
JAEA-Data-Code-2009-002.pdf:14.09MB
Integrated burnup calculation code system SWAT is a system that combines neutronics calculation code SRAC widely used in Japan and point burnup calculation code ORIGEN2. It has been used to evaluate the composition of the uranium, plutonium, minor actinide and the fission products in the spent nuclear fuel. Because of the ability to treat the arbitrary fuel geometry and no requirement of generating the effective cross section data, there is a great advantage to introduce continuous energy Monte Carlo Code into the burnup calculation code. Based on this idea, the integrated burnup calculation code system SWAT3.1 was developed by combining the continuous energy Monte Carlo code MVP and MCNP and ORIGEN2. This report describes the outline, input data instruction and several example of the calculation.
Endo, Satoru*; Tanaka, Kenichi*; Takada, Masashi*; Onizuka, Yoshihiko*; Miyahara, Nobuyuki*; Sato, Tatsuhiko; Ishikawa, Masayoshi*; Maeda, Naoko*; Hayabuchi, Naofumi*; Shizuma, Kiyoshi*; et al.
Medical Physics, 34(9), p.3571 - 3578, 2007/09
Times Cited Count：7 Percentile：25.96(Radiology, Nuclear Medicine & Medical Imaging)Absorbed doses from main charged particle beams and charged-particle fragments have been measured with high accuracy for particle therapy but there are few reports for doses from neutron components produced as fragments. This study describes measurements on neutron dose produced by carbon beam, microdosimetric distributions of secondary neutrons produced by 290 MeV/nucleon carbon beams have been measured by using a tissue equivalent proportional counter (TEPC) at the Heavy Ion Medical Accelerator in Chiba (HIMAC) at the National Institute of Radiological Sciences (NIRS). The ratios of neutrons to charged particle fragments dominated to be 11 to 89 % in the absorbed doses at the side and below the faces of the acrylic phantom (300 mm height 
300 mm width 253 mm thickness).
Kinoshita, Hirohisa; Nohara, Tsuyoshi; Nakata, Takashi*; Ikeda, Yasutaka*; Ito, Kiyoshi*; Otsuki, Kenshiro*; Sagiya, Takeshi*; Takada, Keita*; Toda, Shinji*
Katsudanso Kenkyu, (25), p.27 - 37, 2005/06
Results of numerical analyses and field studies in the epicenter area of the 2000 Tottoriken-seibu earthquake suggest that several research techniques are effective for identifying subsurface active faults unaccompanied with remarkable surface earthquake faults. Field observation of the lineaments found in the area by detailed air-photo interpretation revealed that most of them are accompanied by faults and/or dikes, and some of them show minor slips at the time of the earthquake. Crustal deformation caused by the activity of the subsurface seismogenic faults is deduced by numerical analyses based on seismic and geodetic data. The vertical deformation assumed from the height changes of the terraces along the river across the epicenter area suggests that cumulative uplift and subsidence associated with left-lateral strike-slip has been continuing. Offsets rate of the streams and uplift rate of the river terraces surfaces show good agreement with the estimate from the parameter of the earthquake faults model. Identification of active faults without clear surface evidence before occurrence of earthquakes is a difficult issue, and the techniques adopted in this study will probably provide relevant information effective to locate subsurface active faults.
Okoshi, Kiyonori; Takada, Isao; Mizuhashi, Kiyoshi; Uno, Sadanori; Chiba, Atsuya; Saito, Yuichi; Ishii, Yasuyuki; Sakai, Takuro; Tajima, Satoshi
Dai-16-Kai Tandemu Kasokuki Oyobi Sono Shuhen Gijutsu No Kenkyukai Hokokushu, p.36 - 39, 2004/02
no abstracts in English
Mizuhashi, Kiyoshi; Uno, Sadanori; Okoshi, Kiyonori; Chiba, Atsuya; Saito, Yuichi; Ishii, Yasuyuki; Sakai, Takuro; Kamiya, Tomihiro; Takada, Isao; Tajima, Satoshi
Dai-15-Kai Tandemu Kasokuki Oyobi Sono Shuhen Gijutsu No Kenkyukai Hokokushu, p.33 - 35, 2003/03
no abstracts in English
Saito, Shigeru; Fukaya, Kiyoshi*; Ishiyama, Shintaro; Amezawa, Hiroo; Yonekawa, Minoru; Takada, Fumiki; Kato, Yoshiaki; Takeda, Takashi; Takahashi, Hiroyuki*; Nakahira, Masataka
Journal of Nuclear Materials, 307-311(Part2), p.1573 - 1577, 2002/12
Times Cited Count：2 Percentile：17.03(Materials Science, Multidisciplinary)no abstracts in English
Inoue, Tomio*; Hayakawa, Kazushige*; Shiotari, Harutaka*; Takada, Eiichi*; Torikoshi, Masami*; Nagasawa, Kiyoshi*; Hagiwara, Kazuo*; Yanagisawa, Kazuaki
Journal of Nuclear Science and Technology, 39(10), p.1114 - 1119, 2002/10
Times Cited Count：4 Percentile：29.25(Nuclear Science & Technology)no abstracts in English
Mizuhashi, Kiyoshi; Uno, Sadanori; Chiba, Atsuya; Kitchen, R. L.*; Takada, Isao; Tajima, Satoshi
JNC TN7200 2001-001, p.80 - 83, 2002/01
no abstracts in English
Takada, Isao; Mizuhashi, Kiyoshi; Uno, Sadanori; Okoshi, Kiyonori; Nakajima, Yoshinori; Chiba, Atsuya; Saito, Yuichi; Ishii, Yasuyuki; Sakai, Takuro; Kamiya, Tomihiro; et al.
JNC TN7200 2001-001, p.134 - 137, 2002/01
no abstracts in English
Saito, Shigeru; Fukaya, Kiyoshi; Ishiyama, Shintaro; Amezawa, Hiroo; Yonekawa, Minoru; Takada, Fumiki; Kato, Yoshiaki; Takeda, Takashi; Takahashi, Hiroyuki*; Koizumi, Koichi
JAERI-Tech 2001-035, 81 Pages, 2001/06
JAERI-Tech-2001-035.pdf:18.91MB
no abstracts in English
Takada, Isao; Mizuhashi, Kiyoshi; Uno, Sadanori; Okoshi, Kiyonori; Nakajima, Yoshinori; Chiba, Atsuya; Saito, Yuichi; Ishii, Yasuyuki; Sakai, Takuro; Kamiya, Tomihiro; et al.
JAERI-Conf 2000-019, p.46 - 49, 2001/02
no abstracts in English
Tajima, Satoshi; Takada, Isao; Mizuhashi, Kiyoshi; Uno, Sadanori; Okoshi, Kiyonori; Nakajima, Yoshinori; Saito, Yuichi; Ishii, Yasuyuki; Kamiya, Tomihiro; Sakai, Takuro
Dai-11-Kai Tandemu Kasokuki Oyobi Sono Shuhen Gijutsu No Kenkyukai Hokokushu, p.37 - 40, 1999/01
no abstracts in English
Ishii, Yasuyuki; Tajima, Satoshi; Takada, Isao; Mizuhashi, Kiyoshi; Saito, Yuichi; Uno, Sadanori; Okoshi, Kiyonori; Nakajima, Yoshinori; Kamiya, Tomihiro; Sakai, Takuro
Dai-11-Kai Tandemu Kasokuki Oyobi Sono Shuhen Gijutsu No Kenkyukai Hokokushu, p.72 - 74, 1999/01
no abstracts in English
Tajima, Satoshi; Takada, Isao; Mizuhashi, Kiyoshi; Uno, Sadanori; Okoshi, Kiyonori; Nakajima, Yoshinori; Saito, Yuichi; Ishii, Yasuyuki; Sakai, Takuro; Kamiya, Tomihiro
Dai-12-Kai Tandemu Kasokuki Oyobi Sono Shuhen Gijutsu No Kenkyukai Hokokushu, p.26 - 29, 1999/00
no abstracts in English
Tajima, Satoshi; Takada, Isao; Mizuhashi, Kiyoshi; Uno, Sadanori; Okoshi, Kiyonori; Nakajima, Yoshinori; Saito, Yuichi; Ishii, Yasuyuki; Sakai, Takuro; Kamiya, Tomihiro
F-113-'98/NIES, p.28 - 31, 1998/00
no abstracts in English
Hino, Ryutaro; Suzuki, Kunihiro; Haga, Katsuhiro; Nekoya, Shinichi; Fukaya, Kiyoshi; Shimizu, Saburo; Onuki, Kaoru; Takada, Shoji; Mogi, Haruyoshi; Sudo, Yukio
JAERI-Review 95-016, 115 Pages, 1995/10
no abstracts in English
Tajima, Satoshi; Takada, Isao; Mizuhashi, Kiyoshi; Saito, Yuichi; Uno, Sadanori; Okoshi, Kiyonori; Ishii, Yasuyuki; Nakajima, Yoshinori
Dai-8-Kai Tandemu Kasokuki Oyobi Sono Shuhen Gijutsu No Kenkyukai Hokokushu, p.10 - 14, 1995/07
no abstracts in English
Okubo, Kiyoshi; Suyama, Kenya; Kashima, Takao; Tonoike, Kotaro; Takada, Tomoyuki*
no journal, ,
Criticality safety analysis is necessary for the damaged-fuel handling in the Fukushima Daiichi NPP decommissioning. This presentation show influence of structural materials such as Zry-2, Fe, concrete expected to be present in the damaged fuel. Multiplication factor (kinf) decreases most by replacing moisture, in the damaged fuel, with iron. Replacement of all moisture with Zry-2 gives the same influence as iron, although decrease rate of kinf is lower because of the smaller absorb cross section of Zry-2. Concrete has much less influence due to the neutron moderation by hydrogen contained in concrete, which calls attention on handling of the concrete-fuel mixture. Effect as reflector of the materials is also evaluated.
Tonoike, Kotaro; Okubo, Kiyoshi; Takada, Tomoyuki*
no journal, ,
no abstracts in English
