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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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Latest News
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.
S. Pearlstein
Nuclear Science and Engineering | Volume 68 | Number 1 | October 1978 | Pages 10-18
Technical Paper | doi.org/10.13182/NSE78-A27265
Articles are hosted by Taylor and Francis Online.
The probability table method (PTM), used in unresolved resonance region calculations, assumes that cross sections are not energy correlated. Strong cross-section energy auto-correlations are noted for some heavy nuclides that could affect the use of the PTM in the unresolved resonance region or its extension to the resolved resonance region. Uranium-238 has strong cross-section auto-correlations and is considered a severe test material for the PTM. Monte Carlo calculations of capture rates in 238U at 500, 1000, and 2000 eV do not show differences between the PTM and exact methods within an ∼1% calculational uncertainty. These results show that strong auto-correlations do not interfere with the use of the PTM in the resolved and unresolved resonance regions.
