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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.
Jason Chao, V. K. Chexal, William H. Layman, Gary Vine, Peter J. Jensen, Adi R. Dastur
Nuclear Technology | Volume 83 | Number 3 | December 1988 | Pages 289-301
Technical Paper | Fifth International Retran Meeting / Heat Transfer and Fluid Flow | doi.org/10.13182/NT88-A34142
Articles are hosted by Taylor and Francis Online.
The two power peaks during the Chernobyl accident were analyzed using the system thermal-hydraulic code RETRAN-02. The time and magnitude of the first power peak predicted by the RETRAN model compared well with the data presented by the Soviets. The analysis also revealed that one of the contributing factors to the second power peak was the depressurization of the system. Depressurization occurred upon rupture of the pressure boundary, which was caused by the first power peak. The depressurization of the system generated more voids, resulting in additional reactivity insertion, which produced a second peak. A parametric study showed that the positive reactivity introduced by the scram rods and the reactivity caused by the positive void coefficient were both important in contributing to the accident.
