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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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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.
Frank E. Motley, Richard P. Jenks
Nuclear Technology | Volume 87 | Number 1 | August 1989 | Pages 302-309
Technical Paper | TMI-2: Materials Behavior / Nuclear Safety | doi.org/10.13182/NT89-A27658
Articles are hosted by Taylor and Francis Online.
Work has been performed to develop a Three Mile Island Unit 2 (TMI-2) simulation model for MELPROG/TRAC capable of predicting the observed plant behavior that occurred during the accident of March 1979. A description of the TMI-2 plant model is presented, and calculation results through 174 min of the accident are discussed. Using the boundary conditions recommended for the TMI-2 Analysis Exercise, the calculation predicts pressurizer draining and core recovering prior to fuel rod damage. A parametric calculation (with reduced makeup flow) was also performed and is in better agreement with the observed plant behavior. Efforts are under way to proceed with an accurate simulation through phases 3 and 4 of the accident (174 to 227 min and 227 to 300 min, respectively).
