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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.
J. R. Hofmann
Nuclear Science and Engineering | Volume 68 | Number 1 | October 1978 | Pages 73-90
Technical Paper | doi.org/10.13182/NSE78-A27272
Articles are hosted by Taylor and Francis Online.
A model has been developed to describe the transient pressure field within the interconnected porosity of solid mixed-oxide fast reactor fuel during a reactor transient. The pore gas may be composed of up to two distinct chemical species, so that gas released from fuel grains may differ chemically from the fill gas originally present within the porosity of the fuel. The volume expansion of fuel upon melting is accounted for, but mechanical deformation of the solid fuel is not modeled. Results are presented for a hypothetical unprotected transient over-power accident in a gas-cooled fast reactor with ramp rates of 0.10, 1.0, and 10.0 dollar/s. In these calculations, fuel cladding failure is computed from a linear accumulative damage law and a Larson-Miller parameter correlation.
