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Yamane, Yuichi
Journal of Nuclear Science and Technology, 59(11), p.1331 - 1344, 2022/11
Times Cited Count：0 Percentile：0.01(Nuclear Science & Technology)The reactivity was estimated from a time profile of neutron count rate or a simulated data in a quasi-steady state after sudden change of reactivity or external neutron source strength. The estimation was based on the equation of power in subcritical quasi-steady state. The purpose of the study is to develop the method of timely reactivity estimation from complicated time profile of neutron count rate. The developed method was applied to the data simulating neutron count rate created by using one-point kinetics code, AGNES, and Poisson-distributed random noise and to the transient subcritical experiment data measured by using TRACY. The result shows that the difference of the estimated and reference value was within about 5% or less for (
-1) for simulated data and within about 7% or less for 
-1.4 and -3.1 for the experimental data. It was also shown that the possibility of the reactivity estimation several ten seconds after the status change.
Yamane, Yuichi
Journal of Nuclear Science and Technology, 57(8), p.926 - 931, 2020/08
Times Cited Count：1 Percentile：11.8(Nuclear Science & Technology)An equation of power in subcritical quasi-steady state has been derived based on one-point kinetics equations for the purpose of utilizing it for the development of timely reactivity estimation from complicated time profile of neutron count rate. It linearly relates power, 
, to a new variable 
, which is a function of time differential of the power. It has been confirmed by using one-point kinetics code, AGNES, that the calculated points (
) are perfectly in a line described by the new equation and that points () calculated from transient subcritical experiments by using TRACY made a line with a slope indicated by the new equation.
Nishihara, Kenji; Iwanaga, Kohei; Yamane, Tsuyoshi; Okajima, Shigeaki
JAERI-Research 2002-030, 63 Pages, 2002/12
JAERI-Research-2002-030.pdf:3.81MB
During the experiments using the critical assembly such that reactivity is added to the stationary state and the core shifts to the other stationary state, the neutron flux transitionally changes after some change of the reactivity or source. Inverse kinetics method (IK method) can generally adopted as the technique of obtaining the reactivity and/or source by analyzing the neutron flux. However, the conventional analysis method was not able to obtain the solution with the maximum likelihood considering the error of the measured neutron flux and to estimate the error of the solution. In the present research, by adopting the maximum likelihood methodology to the problem, developed is the technique to obtain the reactivity and source intensity with maximum likelihood and the errors of them. Moreover, the technique is applied to the rod drops experiment in FCA, and the validity of a technique is checked.
Yamashita, Kiyonobu; Takeuchi, Mitsuo; Fujimoto, Nozomu; Fujisaki, Shingo; Nakano, Masaaki*; Nojiri, Naoki; Tamura, Seiji*
Nihon Genshiryoku Gakkai-Shi, 41(1), p.35 - 38, 1999/00
Times Cited Count：0 Percentile：0.01(Nuclear Science & Technology)no abstracts in English
U at FCA, I; Reactivity worth measurement with a small heated sample up to 1500
COkajima, Shigeaki; Oigawa, Hiroyuki; Mukaiyama, Takehiko; Ando, Masaki
Journal of Nuclear Science and Technology, 33(3), p.202 - 210, 1996/03
Times Cited Count：3 Percentile：32.66(Nuclear Science & Technology)no abstracts in English
C in the fast critical facility FCAOkajima, Shigeaki; Oigawa, Hiroyuki; Ando, Masaki; Mukaiyama, Takehiko
Proc. of 9th Int. Symp. on Reactor Dosimetry, 0, p.172 - 179, 1996/00
no abstracts in English
Okajima, Shigeaki; Oigawa, Hiroyuki; Mukaiyama, Takehiko
Journal of Nuclear Science and Technology, 31(10), p.1097 - 1104, 1994/10
Times Cited Count：7 Percentile：56.56(Nuclear Science & Technology)no abstracts in English
optimal estimator for Linear time-invariant system; State space design approach and its application to reactivity estimationSuzuki, Katsuo; Shimazaki, Junya; Shinohara, Yoshikuni
JAERI-M 93-040, 25 Pages, 1993/03
no abstracts in English
C at FCAOkajima, Shigeaki; Oigawa, Hiroyuki; Mukaiyama, Takehiko; *; Kasahara, Y.*; *
Transactions of the American Nuclear Society, 66, p.523 - 524, 1992/11
no abstracts in English
; Fuketa, Toyoshi;
Proc. of the Int. Conf. on Multiphase Flows 91-TSUKUBA,Vol. 2, p.247 - 250, 1991/00
no abstracts in English
;
JAERI-M 89-097, 155 Pages, 1989/08
no abstracts in English
;
JAERI-M 86-012, 179 Pages, 1986/02
no abstracts in English
; ; ; ;
JAERI-M 85-047, 81 Pages, 1985/04
no abstracts in English
;
JAERI-M 84-168, 242 Pages, 1984/10
no abstracts in English
;
JAERI-M 83-193, 112 Pages, 1983/11
no abstracts in English
; ; Matsuura, Shojiro
Nihon Genshiryoku Gakkai-Shi, 19(6), p.380 - 390, 1977/06
Times Cited Count：2no abstracts in English
Journal of Nuclear Science and Technology, 12(7), p.402 - 412, 1975/07
Times Cited Count：5no abstracts in English
; ; ; *
Nihon Genshiryoku Gakkai-Shi, 4(12), p.825 - 834, 1962/00
no abstracts in English
