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Seya, Michio; Kureta, Masatoshi; Soyama, Kazuhiko; Nakamura, Hironobu; Harada, Hideo; Hajima, Ryoichi
Proceedings of INMM 55th Annual Meeting (Internet), 10 Pages, 2014/07
JAEA has been implementing development programs of basic technologies of the following advanced NDA (non-destructive assay) of nuclear material (NM) for nuclear safeguards and security. (1) Alternative to He neutron detection using ZnS/BO ceramic scintillator, (2) NRD (neutron resonance densitometry) using NRTA (neutron resonance transmission analysis) and NRCA (neutron resonance capture analysis), (3) NRF (nuclear resonance fluorescence)-NDA using laser Compton scattered (LCS) -rays (intense mono-energetic -rays). The development program (1) is for NDA systems that use ZnS/BO ceramic scintillator as alternative neutron detector to He for coming shortage of its supply. The program (2) is for a NDA system of isotopic composition measurement (non-destructive mass spectroscopy) in targets such as particle-like melted fuel debris using NRTA and NRCA. The program (3) is for NDA systems using a specific NRF reaction of certain Pu/U isotope caused by mono-energetic LCS -ray with energy tuned to the specific excited state of the isotope. This paper introduces above three programs.
Ueta, Shohei; Emori, Koichi; Tobita, Tsutomu*; Takahashi, Masashi*; Kuroha, Misao; Ishii, Taro*; Sawa, Kazuhiro
JAERI-Research 2003-025, 59 Pages, 2003/11
In the safety design requirements for the High Temperature Engineering Test Reactor (HTTR) fuel, it is determined that "the as-fabricated failure fraction shall be less than 0.2%" and "the additional failure fraction shall be small through the full service period". Therefore the failure fraction should be quantitatively evaluated during the HTTR operation. In order to measure the primary coolant activity, primary coolant radioactivity signals the in safety protection system, the fuel failure detection (FFD) system and the primary coolant sampling system are provided in the HTTR. The fuel and fission product behavior was evaluated based on measured data in the rise-to-power tests (1) to (4). The measured fractional releases are constant at 210 up to 60% of the reactor power, and then increase to 710 at full power operation. The prediction shows good agreement with the measured value. These results showed that the release mechanism varied from recoil to diffusion of the generated fission gas from the contaminated uranium in the fuel compact matrix.
Oishi, Tetsuya; Tsutsumi, Masahiro; Sugita, Takeshi*; Yoshida, Makoto
Journal of Nuclear Science and Technology, 40(6), p.441 - 445, 2003/06
Times Cited Count:1 Percentile:10.87(Nuclear Science & Technology)An EGS4 user code has been developed to design and optimize ray detection systems for several types of radiation sources. The code is fundamentally based on the PRESTA-CG, which is improved on the electron transport in the EGS4 and specialized for the utilization of a combinatorial geometry (CG) method. The main additional functions in the present user code are classified into two parts of the definition of radiation sources and the transport of photons. The developed user code was applied to two types of detection systems in order to demonstrate its availability. As the result, it was found that the present code allows the detailed response analysis of complicated detection systems for several sources with just a simple handling.
Nabeshima, Kunihiko; Ayaz, E.*; Seker, S.*; Barutcu, B.*; Trkcan, E.*
Proceedings of International Conference on Artificial Neural Networks and the International Conference on Neural Information Processing (ICANN/ICONIP 2003), p.406 - 409, 2003/06
On-line plant monitoring system with neural networks and an expert system has been developed for Borssele Nuclear Power Plant (NPP) in the Netherlands. The feedforward and the recurrent neural networks are utilized for plant modeling and anomaly detection. The rule-based expert system is applied for plant diagnosis with the outputs of the neural networks. The off-line results showed that the neural network could model the plant dynamics precisely. The on-line results indicated that the monitoring system could sufficiently diagnose the plant status in real time.
Haruyama, Mitsuo; Shitomi, Hajimu; Nakamura, Kiyoshi
JAERI-Tech 2003-025, 29 Pages, 2003/03
As one of the technical cooperation activity based on the Annex III, the Cooperation in the Area of Reactor Physics and Technology, of the Arrangement between the National Nuclear Energy Agency (BATAN) and the Japan Atomic Energy Research Institute (JAERI), the modification of the Fuel Failure Detection System (FFDS) was carried out by the joint work at the Multi-purpose Reactor RSG-G.A. Siwabessy (RSG-GAS). The system takes the delayed neutron detection method. The design requirements of the modification are, (1) to save the system units currently used and the spares on hand as long as practicable, and / or (2) to replace the system units with those easy to maintain or to obtain at the markets. The modified system obtained around twice of higher sensitivity for delayed neutron detection than before and more reliable monitoring possibility with redundancy. The specification, installation, adjustment methods and characteristics of the modified system and the modus operandi of FFDS at high power reactor operation are described in this paper.
Oishi, Tetsuya; Tsutsumi, Masahiro; Sugita, Takeshi*; Yoshida, Makoto
Proceedings of 1st Asian and Oceanic Congress for Radiation Protection (AOCRP-1) (CD-ROM), 9 Pages, 2002/10
An EGS4 user code has been developed to design gamma ray detection systems for complex shapes of radioactive sources. The code is fundamentally based on the PRESTA-CG, which is improved on the electron transport in the EGS4 and specialized for using a combinatorial geometry (CG) method. The newly added functions are classified mainly into two parts of the transport of particles and the definition of sources. This user code was applied to some detectors used for low-level radioactive wastes monitoring in order to demonstrate the availability of this code. As the result, it was found that the response of anti-Compton spectrometer and the radiation background in a concrete building could be suitably estimated.
Matsubayashi, Masahito; *; J.T.Lindsay*
Nuclear Instruments and Methods in Physics Research A, 424(1), p.165 - 171, 1999/00
Times Cited Count:2 Percentile:27.54(Instruments & Instrumentation)no abstracts in English
Murakami, Yoshio
Fuijikusu, 7(8), p.528 - 531, 1986/08
no abstracts in English
Murakami, Yoshio; ; ; *
JAERI-M 8513, 40 Pages, 1979/10
no abstracts in English
Sanada, Yukihisa; Torii, Tatsuo; Muraoka, Koji*
no journal, ,
Lee, H.-J.; Rodriguez, D.; Rossi, F.; Koizumi, Mitsuo; Takahashi, Tone
no journal, ,