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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Latest News
Senate EPW Committee to hold Nieh nomination hearing
Nieh
The Senate Environment and Public Works Committee will hold a nomination hearing Wednesday for Ho Nieh, President Donald Trump’s nominee to serve as commission at the Nuclear Regulatory Commission.
Trump nominated Nieh on July 30 to serve as NRC commissioner the remainder of a term that will expire June 30, 2029, as Nuclear NewsWire previously reported.
Nieh has been vice president of regulatory affairs at Southern Nuclear since 2021, though since June 2024 he has been at the Institute of Nuclear Power Operations as a loaned executive.
A return to the NRC: If confirmed by the Senate, Nieh would be returning to the NRC after three previous stints totaling nearly 20 years.
Thomas M. Sutton
Nuclear Science and Engineering | Volume 197 | Number 2 | February 2023 | Pages 164-175
Technical Paper | doi.org/10.1080/00295639.2022.2065872
Articles are hosted by Taylor and Francis Online.
The results of neutron Monte Carlo (MC) transport calculations are subject to random fluctuations about their expected values. The term “neutron clustering” refers to situations in which these fluctuations exhibit particularly strong spatial correlations in iterated-fission-source calculations. Various idealized models of the MC process have been developed to study this phenomenon. Over time, these models have evolved to more realistically reflect the algorithms used in MC codes. This paper continues along this path by including the possibility that some neutrons will not terminate in an event that can potentially produce new neutrons and by considering an algorithm without replacement (WOR) for selecting the neutron source sites. It is shown that sampling source sites WOR versus with replacement can greatly reduce the degree of clustering.