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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.
José March-Leuba
Nuclear Technology | Volume 75 | Number 1 | October 1986 | Pages 15-22
Technical Paper | Fission Reactor | doi.org/10.13182/NT86-A15973
Articles are hosted by Taylor and Francis Online.
The development of a reduced-order linear model of the linear dynamic behavior of boiling water reactors (BWRs) is reported. The model is based on a detailed study of the various physical dynamic processes involved. The major results of the work are (a) the pole-zero configuration of the transfer function of this type of reactor has been determined, (b) a minimum of three zeros and four poles is needed to properly represent this transfer function, (c) these poles and zeros have been associated with reactor physical processes such as fuel heat transfer dynamics, and (d) a reduced-order linear model composed of only five equations has been developed. With the appropriate parameters, the model very accurately represents the dynamic behavior of BWRs predicted by fine-mesh computer calculations.
