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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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ANS joins others in seeking to discuss SNF/HLW impasse
The American Nuclear Society joined seven other organizations to send a letter to Energy Secretary Christopher Wright on July 8, asking to meet with him to discuss “the restoration of a highly functioning program to meet DOE’s legal responsibility to manage and dispose of the nation’s commercial and legacy defense spent nuclear fuel (SNF) and high-level radioactive waste (HLW).”
Wm. A. Thomas, E. E. Lewis
Nuclear Science and Engineering | Volume 84 | Number 1 | May 1983 | Pages 67-71
Technical Note | doi.org/10.13182/NSE83-A17459
Articles are hosted by Taylor and Francis Online.
Two iterative algorithms are formulated for the solution of the within-group neutron diffusion equation in three dimensions. The algorithms are highly vectorizable, operating, respectively, on vectors with lengths of order N3/2 and of N2/2, where N is the number of mesh points in each of the three directions. The methods are well suited for present day pipeline computers. On a Cyber-205, they yield floating point operation rates that are higher by a factor of 20 to 30 than those achieved with scalar operations of the same algorithms. Convergence rates, as well as acceleration by two-cyclic overrelaxation, are investigated. For fixed source test problems with 30 X 30 X 30 grids, solutions are obtained in ∼1 s.