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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.
A. Dubi, S. A. W. Gerstl, Donald J. Dudziak
Nuclear Science and Engineering | Volume 68 | Number 1 | October 1978 | Pages 19-30
Technical Paper | doi.org/10.13182/NSE78-A27266
Articles are hosted by Taylor and Francis Online.
A method to calculate volumetric distributions of contributon flux and contributon current is developed utilizing only the forward Monte Carlo approach. Various aspects of tracking contributons are discussed. Basically, the new method consists of sampling secondary particles at collision points occurring within a prespecified volume. A simple connection between integrals over that volume and surface integrals of contributon current is derived, thus providing a means of calculating integral detector responses via a volume integration of the contributon current. This leads to a considerable improvement of the effectiveness with which deep penetration radiation transport problems can be solved relative to analog Monte Carlo. A theoretical and numerical comparison of the performance of this new method with the performance of analog Monte Carlo techniques is carried out. Numerical results are discussed, and a theoretical model to predict the relative advantage of the new method was found to give satisfactory answers. If no biasing techniques are employed in either method, our sample problems show that the contributon method can save up to 90% of computing time over the conventional Monte Carlo method in deep penetration problems when computing an integral response with the same target accuracy.