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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.
Yoshihiro Yamane, Minoru Shinkawa, Kojiro Nishina
Nuclear Science and Engineering | Volume 72 | Number 2 | November 1979 | Pages 244-255
Technical Paper | doi.org/10.13182/NSE79-A19469
Articles are hosted by Taylor and Francis Online.
For single-core reflected neutronic systems, generalized neutron generation time is derived and given physical interpretations in terms of importance. A system kinetic equation containing the moderator region response function previously introduced is reduced by a slow-variation approximation to the form of a conventional one-point kinetic equation, in which a parameter can be identified as generalized neutron generation time by analogy with a bare system. In such a mathematical expression for the parameter, one can further identify the amount of increase due to reflection over the bare system generation time. This amount is found to be the reflection time multiplied by the number of migrations that neutrons undergo between reflector and core in one generation. The theoretical generation time of the SHE assembly, a thermal-energy, graphite-moderated critical assembly, calculated by such a formulation with cylindrical geometry, agreed well with that from pulsed neutron experiments.