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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.
Ge-Ping Yu, Bau-Shei Pei, Ying-Pang Ma
Nuclear Technology | Volume 85 | Number 2 | May 1989 | Pages 147-159
Technical Paper | Fission Reactor | doi.org/10.13182/NT89-A34237
Articles are hosted by Taylor and Francis Online.
A best-estimate transient analysis performed with the RETRAN-02 code is used to demonstrate that two reactor trip setpoints can be modified to improve plant operating margin and eliminate unnecessary reactor trips in the Maanshan three-loop Westinghouse pressurized water reactor. The trip setpoint relaxation analyses involve the steam generator water level and turbine trip. Analytical results show that for a loss-of-secondary-heat-sink event, the steam generator low-low-level reactor trip signal (SGLLRTS) setpoint can be adjusted down from 17 to 5% narrow-range water level span at low power level (<50%) without opening the primary-side power operated relief valves (PORVs). The effects of the automatic control rod on a loss-of-normalfeedwater transient are discussed. The reactor can be tripped by other signals if the SGLLRTS is inhibited at high power level. The turbine trip reactor trip signal setpoint can be lowered from 10 to 30% power. American National Standard design conditions and the prevention of pressurizer PORV opening to avoid a small loss-of-coolant accident are considered the safety criteria for the relaxation of trip setpoints.