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Conference Spotlight
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.
Randy L. Simmons, Niel D. Jones, Frank D. Popa, Donald E. Mueller, James E. Pritchett
Nuclear Technology | Volume 80 | Number 3 | March 1988 | Pages 343-348
Technical Paper | Fission Reactor | doi.org/10.13182/NT88-A34058
Articles are hosted by Taylor and Francis Online.
The design advantages achievable from the use of zirconium diboride (ZrB2) integral fuel burnable absorbers (IFBAs) in two- and three-loop pressurized water reactor (PWR) cores are examined. The ZrB2 IFBAs were designed and have been extensively tested for use in PWRs. Two fuel loading patterns that utilize IFBAs are analyzed: (a) a three-loop core with an 18-month cycle, very low radial leakage loading pattern, and reduced vessel fluence concerns; and (b) a two-loop core with an annual cycle, very low radial leakage loading pattern, and natural uranium axial blankets (low axial leakage). Both designs demonstrate the versatility of IFBAs in difficult fuel loading patterns. Both designs demonstrate well-behaved radial and axial power peaking factors for annual (two-loop core) and 18-month (three-loop core) cycles. The ZrB2 IFBAs also provide added flexibility in the placement of fresh fuel. This flexibility can improve shutdown margin by placing fresh fuel under control rod locations and can improve fuel cycle cost. Neither design would have been possible with discrete burnable absorbers. By analyzing the two very different designs, it can be seen that ZrB2 IFBAs can be used in tightly constrained fuel loading patterns and will provide added flexibility and/or fuel cycle cost savings in future fuel management strategies.
