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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.
Klaus Penndorf
Nuclear Technology | Volume 80 | Number 2 | February 1988 | Pages 282-291
Technical Paper | Advanced Light Water Reactor / Fission Reactor | doi.org/10.13182/NT88-A34052
Articles are hosted by Taylor and Francis Online.
The maximum conversion ratio is relative to the highest degree of undermoderation, which is fixed by the necessities of heat removal. But before this utmost limit is reached, other conditions lowering the conversion become effective. Besides safety-relevant coefficients of reactivity and high fissile inventories, there are other symptoms of a potential economic disequilibrium, which can be visualized by examining the whole domain between the highest possible undermoderation and that of today. The physics underlying the changes in fuel recovery have been investigated by studying the neutron balances and the results have been summarized.
