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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Ho Nieh nominated to the NRC
Nieh
President Trump recently nominated Ho Nieh for the role of commissioner in the Nuclear Regulatory Commission through the remainder of a term that will expire June 30, 2029.
Nieh has been the vice president of regulatory affairs at Southern Nuclear since 2021, though he is currently working as a loaned executive at the Institute of Nuclear Power Operations, where he has been for more than a year.
Nieh’s experience: Nieh started his career at the Knolls Atomic Power Laboratory, where he worked primarily as a nuclear plant engineer and contributed as a civilian instructor in the U.S. Navy’s Nuclear Power Program.
From there, he joined the NRC in 1997 as a project engineer. In more than 19 years of service at the organization, he served in a variety of key leadership roles, including division director of Reactor Projects, division director of Inspection and Regional Support, and director of the Office of Nuclear Reactor Regulation.
M. M. R. Williams
Nuclear Science and Engineering | Volume 199 | Number 7 | July 2025 | Pages 1107-1161
Research Article | doi.org/10.1080/00295639.2024.2444147
Articles are hosted by Taylor and Francis Online.
An extension of the work of Pázsit, Dykin, and Darby on multiplet evaluation has been made using a different method of solution and with the addition of an external reflecting material. The method of solution uses the scalar form of the transport equation to calculate the singlet, doublet, and triplet moments, and in the case when the source configuration requires it, the angular distribution can be obtained in terms of the scalar quantities by direct quadrature. The main contribution of this work is to demonstrate that the scalar approach is convenient, and if energy and anisotropic scattering are required, it is reasonably easy to make use of existing computer codes for solutions of the neutron transport equation. Also, it is shown that the addition of an external reflecting region can have a significant effect on the three multiplicity moments. Some numerical results are given to enable direct comparison to be made with other methods of solution.