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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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.
Mark R. Gilbert
Nuclear Science and Engineering | Volume 199 | Number 1 | April 2025 | Pages S744-S753
Research Article | doi.org/10.1080/00295639.2024.2342506
Articles are hosted by Taylor and Francis Online.
Modern nuclear physics software is well validated, providing advanced capabilities to support the engineering of the future generations of fission and fusion reactors. Transport simulators can model the transport of neutrons through reactor geometries, and inventory codes can accurately predict transmutation and activation. Meanwhile, material modeling applies a variety of techniques to understand how structural damage and composition changes will alter the properties of materials, ultimately limiting their usable lifetime in a reactor. Bridging the gap between nuclear simulation tools and materials modeling is a necessary step if these lifetimes are to be accurately predicted, which, for fusion, is critical to provide the necessary assurance of commercial viability. SPECTRA-PKA is a tool developed to compute the rates of structural damage source events, i.e. the primary knock-on atoms (PKAs), using the same nuclear data as used by transport and inventory simulations. Now, it has been interfaced with the binary collision approximation code SDTrimSP, allowing those PKA events, distributed spatially and temporally in an atomic system, to be converted into damage cascades. This computational infrastructure provides insight into the variation in damage distributions between different materials under the same nuclear environment. Example simulations for materials under fusion reactor conditions demonstrate how the rich detail of the nuclear environment can be applied directly to modeling, without the need for integral-average measures that omit those details.