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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.
Yoichi Watanabe and Charles W. Maynard
Nuclear Science and Engineering | Volume 92 | Number 2 | February 1986 | Pages 212-217
Technical Paper | doi.org/10.13182/NSE86-A18168
Articles are hosted by Taylor and Francis Online.
A hybrid method for two-dimensional neutron transport calculations in (r-z) geometry has been developed. In this method the equation in void regions is solved by the discrete cones (DCN) method, whereas the equation in nonvoid regions is solved by the standard discrete ordinates (SN) method. The two methods are incorporated in one computer program so that a user does not see the difference from a program applying only the SN method. This DCN-SN hybrid method significantly mitigates the ray effects in a void compared with a solution by the same order SN. The method, however, requires a little more computing effort and it is difficult for the method to yield a sufficiently accurate solution for narrow duct streaming problems.