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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.
Bradley J. Knutson, Richard A. Harris
Nuclear Technology | Volume 89 | Number 1 | January 1990 | Pages 9-17
Technical Paper | Fission Reactor | doi.org/10.13182/NT90-A34355
Articles are hosted by Taylor and Francis Online.
Experience using an automated core reactivity monitoring technique at the Fast Flux Test Facility (FFTF) through eight operating cycles is described. This technique relies on comparing predicted-to-measured rod positions to detect any anomalous (or unpredicted) core reactivity changes. Reactivity worth predictions of core state changes (e.g., temperature and irradiation changes) and compensating control rod movements are required for the rod position comparison. A substantial data base now exists to evaluate changes in temperature feedback reactivity effects operational in the FFTF, rod worth changes due to core loading, temperature and irradiation effects, and burnup effects associated with transmutation of fuel materials. This preliminary work focuses on resolving observed reactivity anomalies by evaluating the prediction models using additional zero-power rod worth measurement data along with calculations of rod worths and burnup rates for each cycle using cross-section data processed from the latest ENDF/B-V data set.