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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.
Wataru Shinoda, Susumu Mitake
Nuclear Science and Engineering | Volume 36 | Number 3 | June 1969 | Pages 372-388
Technical Paper | doi.org/10.13182/NSE69-A18735
Articles are hosted by Taylor and Francis Online.
We investigated the xenon-induced spatial oscillations in boiling-water cooled reactors by the use of a three-dimensional xenon dynamics code FILE-6, which solves the one-group neutron diffusion equation simultaneously with the steady state thermo-hydrodynamics equations and with the iodine-to-xenon equations in the time domain. The stability limit of the first azimuthal mode in terms of the void coefficient of reactivity was found to be in a 500 MWe heavy-water-moderated boiling-light-water-cooled reactor. When the height of the reactor core is larger than 7 m, the first axial mode becomes unstable for a void coefficient of +0.05. It has also been shown that (i) a positive (negative) void coefficient may have a stabilizing (destabilizing) effect on the axial higher modes depending on the inlet subcooling, (ii) the mode coupling between the axially zeroth and the first modes through voids has a stabilizing effect, and (iii) when the first azimuthal mode is oscillating, higher harmonics are excited in some of higher modes through the nonlinear reactivity feedback.
