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NRC proposes changes to its rules on nuclear materials
In response to Executive Order 14300, “Ordering the Reform of the Nuclear Regulatory Commission,” the NRC is proposing sweeping changes to its rules governing the use of nuclear materials that are widely used in industry, medicine, and research. The changes would amend NRC regulations for the licensing of nuclear byproduct material, some source material, and some special nuclear material.
As published in the May 18 Federal Register, the NRC is seeking public comment on this proposed rule and draft interim guidance until July 2.
M. M. R. Williams, Edward W. Larsen
Nuclear Science and Engineering | Volume 139 | Number 1 | September 2001 | Pages 66-77
Technical Paper | doi.org/10.13182/NSE01-A2222
Articles are hosted by Taylor and Francis Online.
The majority of earlier work on neutron transport in spatially random media has relied on special models of the random process, closure techniques or perturbation theory. The purpose of the present paper is to further develop a technique, which employs the source-sink method and simulation, and which in principle leads to exact probability distributions, to assess the accuracy of such approximate methods. To this end, we also use perturbation theory, and extend it to eigenvalue problems thereby enabling random fluctuations in reactivity to be studied and some measures of their statistical properties to be calculated. We have found, by comparing results for the variance in the reactivity fluctuations with essentially exact values, that the perturbation method is an accurate way to deal with stochastic equations and is far more efficient numerically than the more exact simulation method.