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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.
Yukiharu Ohga, Kohyu Fukunishi
Nuclear Technology | Volume 71 | Number 2 | November 1985 | Pages 402-410
Technical Paper | Nuclear Safety | doi.org/10.13182/NT85-A33692
Articles are hosted by Taylor and Francis Online.
An on-line method of predicting reactor water level and pressure under small loss-of-coolant-accident (LOCA) conditions has been proposed. The method features initialization of a simplified reactor model in transient conditions. This is done by using plant data in time series and estimating unknown parameters, such as break area, by a nonlinear optimization method. Off-line simulations were performed for small LOCAs (break area: ∼100 cm2) using the results of a reference LOCA analysis code for plant data. These showed that the difference from the reference calculation during a 10-min period was within 10%, normalized by the value at the initialization time, and the estimation error for break area was below 11%. The overall CPU time required for the prediction was below 10 s in a general purpose computer of 10 million instructions per second.
