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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.
T. A. Gabriel, B. L. Bishop
Nuclear Science and Engineering | Volume 68 | Number 1 | October 1978 | Pages 94-99
Technical Note | doi.org/10.13182/NSE78-A27274
Articles are hosted by Taylor and Francis Online.
The sensitivity of primary knock-on atom (PKA) spectra and displacement per atom (dpa) cross sections to different secondary neutron energy and angular distributions and “in-group” weighting schemes is investigated. It is shown that the sensitivity of the PKA spectra and dpa cross sections for the (n, n′ unresolved) and (n, 2n) reactions in iron to different angular distributions and the same secondary neutron spectrum is reasonably large (∼15%). For grossly different secondary neutron spectra and the same angular distribution, the change in the dpa cross section is smaller than one would initially expect. It is also shown that for aluminum, the sensitivity of dpa cross sections to different in-group weighting schemes is, for the most part, small.
