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Conference Spotlight
2025 ANS Winter Conference & Expo
November 8–12, 2025
Washington, DC|Washington Hilton
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
DNFSB’s Summers ends board tenure, extending agency’s loss of quorum
Lee
Summers
The Defense Nuclear Facilities Safety Board, the independent agency responsible for ensuring that Department of Energy facilities are protective of public health and safety, announced that the board’s acting chairman, Thomas Summers, has concluded his service with the agency, having completed his second term as a board member on October 18.
Summers’ departure leaves Patricia Lee, who joined the DNFSB after being confirmed by the Senate in July 2024, as the board’s only remaining member and acting chair. Lee’s DNFSB board term ends in October 2027.
Hideko Komoriya, Wallace F. Walters
Nuclear Science and Engineering | Volume 64 | Number 2 | October 1977 | Pages 576-581
Technical Paper | doi.org/10.13182/NSE77-A27391
Articles are hosted by Taylor and Francis Online.
The effectiveness of the energy-dependent finite element method (EDFEM) as applied to two-dimensional multigroup diffusion problems is investigated. The EDFEM couples the finite element method (FEM) formalism with the energy-dependent element size scheme. The EDFEM allows the elements to straddle material interfaces if certain conditions are satisfied; this method is especially suitable for heterogeneous reactor calculations. Comparisons of the results obtained by the EDFEM, the FEM, and the finite difference method for a ZION I pressurized water reactor model are presented. A significant reduction of the total number of unknowns involved in the problem is accomplished by using the EDFEM, which yields a reduction of the computing time by 30%.
