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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.
Nobuo Sasamoto, Kiyoshi Takeuchi
Nuclear Science and Engineering | Volume 71 | Number 3 | September 1979 | Pages 330-342
Technical Note | doi.org/10.13182/NSE79-A19071
Articles are hosted by Taylor and Francis Online.
An improvement in the approximation of the spatial distribution of the source term in the PALLAS discrete-ordinates code by a combination of linear and exponential functions results in a reduction of numerical errors compared with those due to the use of only a linear approximation based on a direct integration method. The results obtained by the improved approximation for one-dimensional radiation transport calculations are compared with those by the PALLAS code with the original linear approximation and by the SN code ANISN. For further verification, this improved approximation is applied to two-dimensional neutron transport calculations, in which numerical errors due to the spatial mesh sizes used in the calculations are studied. As a result, it is found that the use of the improved approximation gives reasonable solutions with small numerical errors, irrespective of the spatial mesh size in both one- and two-dimensional PALLAS calculations of radiation transport.
