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Conference Spotlight
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.
Hsiang-Shou Cheng, Ming-Shih Lu, David J. Diamond
Nuclear Technology | Volume 41 | Number 3 | December 1978 | Pages 283-298
Technical Paper | Reactor | doi.org/10.13182/NT78-A32114
Articles are hosted by Taylor and Francis Online.
The space-time effects associated with the void reactivity feedback in a commercial boiling water reactor were studied with the aid of the two-dimensional (R,Z) time-dependent coupled neutronics thermal-hydraulics computer code BNL-TWIGL. The statistical weight factor (SWF), which equates a point-reactor model to an appropriate space-dependent model, was used to quantify these effects. The SWF varied for the different reference reactor conditions and types of void perturbations considered. Its significant magnitude demonstrated that unless proper account is taken of multidimensional effects in plant transient calculations, the void feedback will be incorrect, and this will lead to errors in power and temperature. The presence of bypass void was found to increase the void reactivity feedback. The influence of other feedback mechanisms was studied, and a suggestion was offered for obtaining a measurement of the void reactivity coefficient.
