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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.
F. Carloni, M. Marseguerra
Nuclear Science and Engineering | Volume 71 | Number 3 | September 1979 | Pages 319-326
Technical Paper | doi.org/10.13182/NSE79-A19069
Articles are hosted by Taylor and Francis Online.
The problem of determining the neutron and count distributions in a multiplying assembly has been independently solved by many authors over the past 30 years. In all cases, the quadratic approximation is used for the probability generating function of the neutrons emitted per fission. In the present paper, this approximation is interpreted as one that almost exactly accounts for the fluctuations of two small samples, one of which is withdrawn from the totality of the neutrons existing at a given time, while the second is taken from all those that have been absorbed up to that time. The observed counts constitute the sample taken from the absorbed neutron population, while the usual distribution of the whole neutron population is obtained from that of the sampled neutrons by performing a suitable change of variable. According to this interpretation, the neutron distribution so obtained may contain rather large errors, and the only case for which we can say that the approximation is safe is that of the count distribution, provided the detector efficiency is kept very small. Indeed, numerical examples show that the relative errors in most cases are of one or two orders of magnitude larger for the neutron distribution than those for the count distribution.