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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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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.
G. Th. Analytis, J. K.-H. Karlsson {ti}Spatial Neutronic Decoupling of Large Fast Breeder Reactor Cores: Application to Nuclear Core Design Method
Nuclear Science and Engineering | Volume 131 | Number 2 | February 1999 | Pages 286-292
Technical Note | doi.org/10.13182/NSE99-A2036
Articles are hosted by Taylor and Francis Online.
It is well known that after one of the spatial harmonics of a boiling water reactor (BWR) is driven toward limit-cycle oscillations with a decay ratio very close to 1, the nonlinear behavior of the system starts to manifest itself, and a series of resonances appears at frequencies that are multiples of the characteristic oscillation frequency (commonly called harmonic frequencies). Several such resonances have been clearly identified during measurements in BWRs during which the system is in the unstable, limit-cycle oscillations regime. The ability to identify three and possibly four of these harmonic resonance peaks in the neutron spectra of Ringhals-1 is reported. For the measurements to be analyzed, these resonances are due to the limit-cycle oscillations not of the fundamental but of the first spatial harmonic of the neutron flux.
