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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Empowering the next generation: ANS’s newest book focuses on careers in nuclear energy
A new career guide for the nuclear energy industry is now available: The Nuclear Empowered Workforce by Earnestine Johnson. Drawing on more than 30 years of experience across 16 nuclear facilities, Johnson offers a practical, insightful look into some of the many career paths available in commercial nuclear power. To mark the release, Johnson sat down with Nuclear News for a wide-ranging conversation about her career, her motivation for writing the book, and her advice for the next generation of nuclear professionals.
When Johnson began her career at engineering services company Stone & Webster, she entered a field still reeling from the effects of the Three Mile Island incident in 1979, nearly 15 years earlier. Her hiring cohort was the first group of new engineering graduates the company had brought on since TMI, a reflection of the industry-wide pause in nuclear construction. Her first long-term assignment—at the Millstone site in Waterford, Conn., helping resolve design issues stemming from TMI—marked the beginning of a long and varied career that spanned positions across the country.
Jin-Young Cho, Jae-Seung Song, Chung-Chan Lee, Sung-Quun Zee, Jae-Il Lee, Kil-Sup Um
Nuclear Technology | Volume 161 | Number 1 | January 2008 | Pages 57-68
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT08-A3913
Articles are hosted by Taylor and Francis Online.
A lumped-refined multichannel analysis scheme is developed for a high-fidelity thermal-hydraulic (T-H) calculation through neutronics code coupling and applied to a control element assembly (CEA) ejection accident of the Ulchin Unit 3 nuclear power plant to quantify the conservatism of the conventional scheme. The high-fidelity core minimum departure from nucleate boiling (DNB) ratio calculation is realized by coupling more than two TORC dynamic link libraries (DLLs) under the control of the neutronics code, one for the lumped multichannel calculation and the others for the refined subchannel calculations. Realistic radial boundary conditions are supplied from the lumped multichannel calculation to the refined TORC DLL through the neutronics code. The CEA ejection accident problem is simulated from the DNB limiting conditions for operation condition, which is searched by adjusting the core radial peaking factor at a 30% axial offset power shape. The results indicate that the simplified hot-channel model contains ~15 and 5% conservatism in the core minimum DNB ratio and in the number of failed fuel rods, respectively, and reveals that those conservatisms are mainly due to the unrealistic isolated boundary condition. Therefore, it is concluded that the developed scheme can be effectively used to quantify the conservatism of a conventional DNB evaluation scheme.
