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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.
R. T. Santoro, R. A. Lillie, R. G. Alsmiller, Jr., J. M. Barnes
Nuclear Science and Engineering | Volume 70 | Number 3 | June 1979 | Pages 225-242
Technical Paper | doi.org/10.13182/NSE79-A20145
Articles are hosted by Taylor and Francis Online.
Two- and three-dimensional radiation transport methods have been employed to estimate the nuclear performance of the neutral beam injectors being designed for the Tokamak Fusion Test Reactor. The nuclear heating rates and neutron and gamma-ray energy spectra have been calculated at various locations in a detailed calculational model of the injector using Monte Carlo methods. Calculations have also been carried out using discrete-ordinates methods to obtain estimates of these data in a two-dimensional model of the injector. The two-dimensional calculational procedure was developed as an analytic tool for more cost-efficient scoping and parametric studies of the effects of design changes on the injector performance due to the streaming of 14-MeV neutrons. The nuclear responses and spectra obtained using the two-dimensional calculational model agree with the more definitive data obtained using the three-dimensional model within a factor of ∼5.
