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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.
Douglas R. Smith, Robert W. Albrecht
Nuclear Technology | Volume 79 | Number 1 | October 1987 | Pages 35-50
Technical Paper | Fission Reactor | doi.org/10.13182/NT87-A16003
Articles are hosted by Taylor and Francis Online.
A recent development in passive safety devices for advanced liquid-metal reactors is the installation of manometerlike core assemblies called gas enhancement modules (GEMs). Knowledge of the liquid sodium level within the GEMs is required to monitor GEM operation. A microwave, resonant cavity level measurement technique has been laboratory tested on a scale model of a GEM assembly in a nonsodium environment. The theory behind this method is discussed, and the experimental results are shown to compare well with those predicted by theoretical calculation. The resonant cavity level detector tracked extremely well over the desired 0.1524- to 1.1176-m range of operation and provided accurate, reproducible results well within the desired ±25.4-mm actual level. When tested for vibrational stability, level errors of only 0.254 mm were observed. The effects of material differences between the experimental GEM (copper) and the actual GEM (Type 304 stainless steel) are calculated. The actual GEM will have poorer resolution but still be within ±25.4-mm actual level. Temperature effects are also calculated and produce a 10.5 kHz/°C shift in resonant frequency, which could cause the indicated level to exceed the ±25.4 mm allowed if large (∼149°C) temperature changes occur.
