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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.
Keiichiro Tsuchihashi, Yukio Ishiguro, Kunio Kaneko
Nuclear Science and Engineering | Volume 73 | Number 2 | February 1980 | Pages 164-173
Technical Paper | doi.org/10.13182/NSE80-A18696
Articles are hosted by Taylor and Francis Online.
A simplified method based on the intermediate resonance approximation is proposed to deal with the double heterogeneity encountered in design calculations of high-temperature gas-cooled reactors. First, a fuel rod with grain structure is homogenized by introducing an equivalent homogeneous material, in the form of an intermediate resonance approximation, that contains a fictitious moderator substituted for both the grain heterogeneity and the scattering in moderator region. Second, the cluster configuration of the homogenized rods is treated by use of the fictitious moderator. This method is shown to offer a convenient and simple means with good accuracy and short computing time when combined with the “table look-up” method of resonance shielding factors.
