Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Imamoto, Nobuo; Koiso, Keiichi
JAEA-Technology 2012-016, 27 Pages, 2012/06
The shaking table tests have been employed to evaluate the seismic fragilities of the machine-electric equipments. Through the shaking table test, in ordinarily it is depending on resonance frequency, repetitive adjustments are needed to search a normal/malfunction boundary. However, a small relay used for the electric panel and the control system, can not be measured the resonance frequency because the acceleration sensor installation affects the vibration characteristic of the test body. And more, the moving parts leading to a relay malfunction is settled in the case, it can not be carried out direct measurement of the vibration. To improve the shaking table test methods, magnetization current perturbation method was invented and developed. Instead the mechanical shaking force, magnetization current perturbation method employs vibrating electromagnet force. Moreover, obtained impedance characteristic curve, the resonance frequency can be obtained by fitting to a theoretical curve. This paper deals with the principle of the magnetization current perturbation method, theoretical derivation of impedance, measurement electronics circuit, and system design and test results.
Sakaguchi, Shinobu; Tachibana, Ikuya; Koshino, Katsuhiko; Shirozu, Hidetomo; Shirai, Nobutoshi; Imamoto, Nobuo; Tomita, Tsuneo; Tobita, Hiroo; Yamanaka, Atsushi; Kobayashi, Daisuke; et al.
JAEA-Technology 2011-006, 24 Pages, 2011/03
In the Niigataken Chuetsu-oki Earthquake on 2007, observed earthquake motion exceeded design base at the Kashiwazaki Kariwa nuclear plant. However, there was no earthquake damage in safety important equipments to stop reactor, to cool reactor, and to contain radioactive materials. One of this reason is said that many safety margin are included in the design and the permissible value. To know more accurate safety margin, shearing force examinations for the base bolts were conducted. In examinations, delegate test-bolts were made; the test bolts were selected from heavier equipment in Tokai Reprocessing Plant. In this report, the shearing strength obtained from the examinations shows more accurate safety margin.
Imamoto, Nobuo
Gijutsushi, 21(6), p.12 - 15, 2009/06
Recently, interest in the nuclear power generation is becoming large globally. The nuclear fuel cycle facility is required to possess safety measures in the design and the operation. In addition, it is required to obtain the relief, the PE of Nuclear and Radiation is expected to play a role in risk communication.
Motohashi, Masahiro; Kyue, Tadashi; Imamoto, Nobuo; Ichinosawa, Hitoshi; Inanobe, Kazuhide*
Saikuru Kiko Giho, (27), p.96 - 97, 2005/06
The general-condition report of LWTF is carried to
Masahiro, Motohashi,; Tadashi, Kyue,; Imamoto, Nobuo; Ichinosawa, Hitoshi; Inanobe, Kazuhide*
Saikuru Kiko Giho, (26), p.131 - 132, 2005/00
The general-condition report of LWTF is carried to "JNC Technical Review No.26 2005.3"
Masahiro, Motohashi,; Tadashi, Kyue,; Imamoto, Nobuo; Ichinosawa, Hitoshi; Inanobe, Kazuhide*
Saikuru Kiko Giho, (24), p.82 - 83, 2004/00
The general-condition report of LWTF is carried to "JNC Technical Review No.24 2004.9"
Masahiro, Motohashi,; Tadashi, Kyue,; Imamoto, Nobuo; Ichinosawa, Hitoshi; Inanobe, Kazuhide*
Saikuru Kiko Giho, (25), 132- Pages, 2004/00
The general-condition report of LWTF is carried to "JNC Technical Review No.25 2004.12"
Saito, Yasuo; ; ;
Proceedings of 8th International Conference on Nuclear Engineering (ICONE-8) (CD-ROM), 0 Pages, 2000/00
None
; Saito, Yasuo; ;
Proceedings of 8th International Conference on Nuclear Engineering (ICONE-8) (CD-ROM), 0 Pages, 2000/00
None
Miura, Akihiko;
JNC TN8410 99-044, 189 Pages, 1999/10
This report includes several results that were made by calculation with several methods to clarify the cause of the fire and explosion incident. In the early times, we didn't have exact information of chemicaI property, reaction rate and any physical constants that we needed. But because the only data that indicate the cooling process of bituminized product was reported, we made heat-transporting calculation with taking this data. Based on the theory of the thermal hazard evaluation that was called Semenov theory or Frank-Kamenetskii theory, the amount of heat generation was estimated using the heat transporting calculation. Common theories were introduced in first section. In the second section, several results of heat transporting calculation were indicated. Calculations were made as follows. First, the model of bituminized product that was filled in the drum was created with the data of cooling process. Second, when the heat was generated in the drum, time-dependent temperature distribution was calculated. And last, judging from the balance of heat generation and heat radiation the critical heat rate was estimated.
Shigetome, Yoshiaki; ; Yamanouchi, Takamichi; Oda, Yoshihiro;
PNC TN8410 98-088, 48 Pages, 1998/05
At the fire and explosion incident of Bituminization Demonstration Facility, the fault of cell ventilation system (plugging of the HEPA filter) occurred in a short time. In addition the breakdown of the filter occurred at the explosion which happened ten hours after the extinguishment of the fire. Investigation of filter damage was conducted in order to know the extent of the breakdown, the contamination by radioactivity and soot mass gain of HEPA filter. Scanning electron micrograph (SEM) was also used to observe the appearance of soot adhesion on the filter media. This report shows the result of the investigation.
Imamoto, Nobuo; Koiso, Keiichi
no journal, ,
no abstracts in English