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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.
Bau-Shei Pei, Ge-Ping Yu, Guei-Ching Lin, Yin-Pang Ma
Nuclear Technology | Volume 90 | Number 1 | April 1990 | Pages 49-62
Technical Paper | Nuclear Safety | doi.org/10.13182/NT90-A34385
Articles are hosted by Taylor and Francis Online.
Due to the potential threat of reactor coolant system (RCS) overpressurization, loss-of-normal-feed-water (LONF) transients without reactor trip have received special attention in the analysis of pressurized water reactor (PWR) anticipated transients without trip (ATWT). The U.S. Nuclear Regulatory Commission requires every PWR to be equipped with an ATWT mitigation system actuation circuitry (AMSAC) so that the turbine will be tripped and auxiliary feedwater (AFW) added when an LONF transient occurs. An AMSAC design proposed by Westinghouse Electric Corporation will be installed in both units of the Maanshan Nuclear Power Station (MNPS) to deal with ATWTs under LONF transient conditions. A best-estimate transient analysis performed with the RETRAN-02/MOD3 code is used to assess the safety function of the actuation circuitry designed for MNPS. Analytical results show that the peak RCS pressure will not exceed the 22.16-MPa safety limit if the moderator temperature coefficient is sufficiently negative and the actuation circuitry functions normally. Effects of the moderator temperature coefficient, the Doppler coefficient, pressurizer power-operated relief valves, effective time of the AFW system, the steam dump system, and the automatic control rod system are discussed.
