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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.
Dov Ingman, Leib Reznik
Nuclear Technology | Volume 74 | Number 3 | September 1986 | Pages 243-259
Technical Paper | Fission Reactor | doi.org/10.13182/NT86-A33827
Articles are hosted by Taylor and Francis Online.
A multicomponent system, specified by a high level of power generation and transformation as a thermodynamics system with strong interaction between the elements, is considered in the reliability analysis. The reliability of each system element is dependent on the average energy of the system. The approach, which aims to give proper consideration to the system / element interaction, is based on the energy accumulation aspects of various processes of the element and the system deterioration. The phenomena of coherent blockages of core coolant channels for different geometrical configurations serve to demonstrate that there exists, in principle, a possibility of failure of the system through cooperative failures of its elements. The investigation is based on statistical thermodynamics, particularly on the approach of “phase transitions,” and also on the percolation theory results. The developed model has been employed to evaluate the propagation rate of the subchannel blockages under critical conditions. In spite of the simplified character of the model, it has demonstrated the necessity of including consideration of collective phenomena in the reliability analysis of multicomponent systems characterized by a high power level. The developed approach permits construction of a minimum set of generalized system parameters that describe the critical system behavior. A quantitative determination of these parameters and an application of the model to specific reactor core designs and severe transient scenarios will be the subject of further investigation.
