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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.
Ely M. Gelbard, Yen-Wan H. Liu, Laura Olvey
Nuclear Science and Engineering | Volume 101 | Number 2 | February 1989 | Pages 166-178
Technical Paper | doi.org/10.13182/NSE89-A23605
Articles are hosted by Taylor and Francis Online.
Embedded in multidimensional nodal transport computations is the solution of transverse-integrated one-dimensional transport equations. Since, in these embedded one-dimensional computations, fluxes on boundaries are double P1 (DP1), it is generally assumed that the one-dimensional solutions, in the small-mesh limit, approach DP1 solutions. It is shown that this is not necessarily true. Small-mesh limits of nodal equations are derived, and it is shown that these are substantially worse than the DP1 equations under certain circumstances. Alternative nodal equations (which do have a DP1 small-mesh limit) are proposed.