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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.
R. K. S. Rathore, P. Munshi, R. K. Jarwal, I. D. Dhariyal
Nuclear Technology | Volume 82 | Number 2 | August 1988 | Pages 227-234
Technical Paper | Heat Transfer and Fluid Flow | doi.org/10.13182/NT88-A34109
Articles are hosted by Taylor and Francis Online.
Computerized tomography (CT) has been demonstrated to be a good technique for measuring point density (void fraction) in two-phase flow systems. Recently, improvements have been suggested regarding the choice of filter functions in CT methods. These methods are essentially based on the discrete implementation of the radon inversion formulas that are widely used in the medical imaging area. Such methods do not require any a priori information regarding the distribution of the density (or the void fraction). A very simple method involving the tomographic chord-segment inversion has been developed and tested for two-phase flows having radially symmetric density distributions. This method is much simpler and consumes less CPU time than more general methods of tomographic reconstruction. For test functions, the reconstructed density distributions are almost exact. For air/water bubbly flow data, the reconstructed values have a maximum deviation of ±0.03 g/cm3. The range of investigation of the air/water flow data was 0.6 to 0.9 g/cm3, i.e., a void fraction range of 40 to 10%. These results are comparable to the results obtained by the more general methods based on the radon inversion formulas.
