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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.
P. Barbucci, F. Di Pasquantonio
Nuclear Science and Engineering | Volume 63 | Number 2 | June 1977 | Pages 179-187
Technical Paper | doi.org/10.13182/NSE77-A27021
Articles are hosted by Taylor and Francis Online.
The use of supplementary exponential equations to solve the transport equation by means of the discrete ordinate method has been studied. It is shown that the set of final equations so obtained can be easily and quickly solved on the computer using the same iterative procedure employed in standard SN codes. The new method is implemented on ANISN and DOT-III codes. This work refers only to the one-dimensional case. Extensive numerical experiments for neutrons and gamma rays showed that the exponential scheme increases the convergence rate of the iterative procedure and always overestimates the “reference solution” by very small amounts for the finest mesh size and by reasonable amounts for the largest mesh size. For its own structure, the exponential method always gives positive angular fluxes without any adjustment techniques provided the source is non-negative.