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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.
José M. Aragonés
Nuclear Science and Engineering | Volume 68 | Number 3 | December 1978 | Pages 281-298
Technical Paper | doi.org/10.13182/NSE78-A27306
Articles are hosted by Taylor and Francis Online.
A method is developed for calculating effective neutron cross sections in the resolved resonance groups of homogeneous mixtures of cylindrical cells in regular reactor lattices. A rigorous treatment of the nucleonic and neutronic problems provides accurate numerical solutions with detailed dependence in energy and space for both Doppler-broadened cross sections and self-shielded neutron fluxes. The common simplifying approximations are not introduced, so that the method is used as a reference to analyze some of the detailed self-shielding effects that are commonly ignored or approximated in applications ranging from homogeneous mixtures of different resonant nuclides to cylindrical cells with nonuniform temperatures and concentrations within the fuel.
