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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.
Rei Kimura, Yuki Nakai, Satoshi Wada
Nuclear Science and Engineering | Volume 195 | Number 12 | December 2021 | Pages 1279-1290
Technical Paper | doi.org/10.1080/00295639.2021.1908081
Articles are hosted by Taylor and Francis Online.
A novel ex-core-detector–based core power reconstruction method is presented. The method uses power correlations between fuel regions and can be applied to a real-time small reactor core monitoring system especially for the detection of abnormal behavior. The use of ex-core detectors reduces the installation and maintenance costs of small modular reactors (SMRs) compared to conventional in-core detectors. To construct the power distribution with ex-core-detector count rates, it is necessary to account for the scattering and absorption reactions of neutrons within the core that make it difficult to extract information directly from the central core region. In the proposed method, detector responses and power correlations are preevaluated and revised by mathematical transformation. Monte Carlo simulations using the realistic SMR core design MoveluXTM demonstrated that the present method is capable of reconstructing the core power distributions within an average error of 10% using the count rates of the ex-core detectors. Also, the reconstruction successfully identified the position of abnormal power peaks in the central core region and an unbalanced power distribution.
