Stochastic estimation of radionuclide composition in wastes generated at Fukushima Daiichi Nuclear Power Station using Bayesian inference

Sugiyama, Daisuke*; Nakabayashi, Ryo*; Tanaka, Shingo*; Koma, Yoshikazu; Takahatake, Yoko

Journal of Nuclear Science and Technology, 58(4), p.493 - 506, 2021/04

https://doi.org/10.1080/00223131.2021.1884137

Experimental verification for real-time environmental emergency response system; WSPEEDI by European tracer experiment

Furuno, Akiko; Terada, Hiroaki; Chino, Masamichi; Yamazawa, Hiromi*

Atmospheric Environment, 38(40), p.6989 - 6998, 2004/12

https://doi.org/10.1016/j.atmosenv.2004.02.074

We have been developing the computer-based emergency response system WSPEEDI which predicts long-range atmospheric dispersion of radionuclides discharged into the atmosphere due to a nuclear accident. The first version of WSPEEDI has a shortage that the spatial and temporal variation of the atmospheric boundary layer was very simply parameterized. Therefore we have developed the new version accomplished with the atmospheric dynamic model, in which the turbulent diffusivity in the mixing layer is calculated with a turbulence closure model. This paper describes the results of performance evaluation of the new version of WSPEEDI by comparing the simulation results with the European Tracer Experiment data. As a result of the verification, it was shown that the increase in the horizontal resolution largely improved the accuracy of the model prediction. The use of the turbulence closure model instead of the simple parameterization largely contributed to improve reproducibility of horizontal distribution of plumes.

Effects of model complexity on uncertainty estimates

M.Elert*; A.Butler*; J.Chen*; C.Dovlete*; A.Konoplev*; A.Golubenkov*; M.Sheppard*; Togawa, Orihiko; T.Zeevaert*

Journal of Environmental Radioactivity, 42, p.255 - 270, 1999/00

https://doi.org/10.1016/S0265-931X(98)00058-7

no abstracts in English

Development elementary models of comprehensive safety assessment model for shallow land disposal of low-level radioactive wastes, IV; Modeling of radionuclide leaching from a double barriered waste package

; Matsuzuru, Hideo;

JAERI-M 88-089, 36 Pages, 1988/05

JAERI-M-88-089.pdf:1.08MB

no abstracts in English

Parameter optimization of the solute transport equations from in situ tracer test of the excavation damaged zone

Fairat, K.; Takeda, Masaki; Ozaki, Yusuke

no journal, , 

Excavation damaged zones (EDZs) formed around a tunnel may allow nuclides to migrate along the pathways. The characteristics of solute transport in fracture and rock matrix inside EDZs were investigated by in situ tracer test. The parameters of solute transport equations were optimized to satisfy the measured breakthrough curve (BTC) and estimate the advective and dispersive effect along with the diffusional transfer. The result shows that most tracers likely move along the fracture and do not diffuse into the matrix under the in situ experimental condition.