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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.
Jae Jun Jeong, Deog Yeon Oh, Hee Cheon No, Soon Heung Chang, Sung Jae Cho, Hwang Yong Jun, Yong Kwan Lee
Nuclear Technology | Volume 90 | Number 3 | June 1990 | Pages 356-370
Technical Paper | RELAP/MOD2 / Fission Reactor | doi.org/10.13182/NT90-A34400
Articles are hosted by Taylor and Francis Online.
A compact real-time simulator for two-loop pressurized water reactor plants, FISA-2/WS (Fully Implicit Safety Analysis-2 /Work Station), has been improved and adapted to the Sun 386i computer, which was developed for classroom training in support of full-scale simulators, for transient analysis, engineering studies, and emergency drills. The FISA-2/ WS simulator package is divided into three modules: plant, on-line graphic display, and interactive communication. The plant module consists of models for core kinetics, reactor coolant system, steam generator, main steam line, and control and safety systems. Each of the models is optimized to obtain the capability of real-time simulation. Simulation results are displayed periodically at a user-specified time interval on a color monitor by the on-line graphic display module. The FISA-2/WS interactive communication module enables the user to initiate or mitigate accidents and to select one of the menu-driven graphic displays with the mouse and keyboard. Several nuclear steam supply system transients have been simulated by FISA-2/WS. The results presented here are obtained from simulations of steady state, turbine load change transient, and small-break loss-of-coolant accidents. The results of FISA-2/WS are in good agreement with plant data and the results of RELAP5/MOD2, and the fast running capability is also confirmed.
