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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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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.
I. Kiss, Sz. Vass
Nuclear Science and Engineering | Volume 69 | Number 1 | January 1979 | Pages 1-5
Technical Paper | doi.org/10.13182/NSE79-A21278
Articles are hosted by Taylor and Francis Online.
An attempt is made to describe the in-process inventory of enrichment cascades with a close separation process as a product of gas in-flow and the average holdup time of gas molecules. The holdup time is calculated on the basis of a simple random-walk model of the transients and the output response to input perturbation. Calculations are carried out for a gaseous diffusion plant producing slightly enriched uranium. Experimental determination is proposed for safeguards purposes.
