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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Senate EPW Committee to hold Nieh nomination hearing
Nieh
The Senate Environment and Public Works Committee will hold a nomination hearing Wednesday for Ho Nieh, President Donald Trump’s nominee to serve as commission at the Nuclear Regulatory Commission.
Trump nominated Nieh on July 30 to serve as NRC commissioner the remainder of a term that will expire June 30, 2029, as Nuclear NewsWire previously reported.
Nieh has been vice president of regulatory affairs at Southern Nuclear since 2021, though since June 2024 he has been at the Institute of Nuclear Power Operations as a loaned executive.
A return to the NRC: If confirmed by the Senate, Nieh would be returning to the NRC after three previous stints totaling nearly 20 years.
Hangbok Choi, Myunghee Choi, Ryan Hon
Nuclear Technology | Volume 205 | Number 3 | March 2019 | Pages 486-505
Technical Paper | doi.org/10.1080/00295450.2018.1495001
Articles are hosted by Taylor and Francis Online.
Calculations have been conducted for the KRITZ-2 (KRITZ-LWR-RESR-001/002/003) and the Fast Flux Test Facility (FFTF) (FFTF-LMFR-RESR-001) Nuclear Energy Agency benchmark problems using the PARCS reactor simulation code with lattice parameters generated by the DRAGON reactor physics code and with the MCNP6 Monte Carlo code. The benchmark analyses examined the DRAGON cross-section library, PARCS energy group structure, DRAGON fuel assembly modeling, and nuclide self-shielding effect. For KRITZ-2, the PARCS 2-group core calculations with a DRAGON 361-group library based on ENDF/B-VII.1 reproduced the benchmark keff with a root-mean-square (rms) error of 0.19% δk. DRAGON/PARCS also predicted the fission rates within 5%. The MCNP results are consistent with the DRAGON/PARCS results but with a small underestimation when compared to the benchmark value. For FFTF, the PARCS 33-group core calculations underpredicted the benchmark keff by 0.19% δk while the MCNP calculation overpredicted the benchmark keff by 0.23% δk. The neutron spectrum distributions calculated by PARCS and MCNP are consistent with measured data. Since the energy boundary values of the measured neutron spectrum are not available, the calculated spectra could not be directly compared to the measured value. The DRAGON/PARCS solution to a numerical benchmark of a gas-cooled fast reactor (GFR), i.e., the Energy Multiplier Module, predicted the keff and assembly power with 0.46% δk and 3.7% rms error, respectively, when compared to the MCNP simulation. The benchmark calculations of the selected thermal and fast reactors have shown that DRAGON/PARCS simulates small reactor cores with good accuracy.
