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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.
Albert G. Gu
Nuclear Technology | Volume 177 | Number 2 | February 2012 | Pages 157-175
Technical Paper | Fission Reactors | doi.org/10.13182/NT12-A13363
Articles are hosted by Taylor and Francis Online.
This paper introduces a combined micro and macro (CMM) parameter perturbation theory for boiling water reactor (BWR) lattice design and optimization, which involves a large number of independent design variables and a large scale of variations. With this theory, engineers are able to meet the challenges from both accuracy and speed requirements. This theory was applied to the BWR fuel assembly lattice design in AREVA. A BWR fast lattice simulator (FLS) and a BWR fuel assembly lattice optimizer (BALO) were built and assisted engineers working on the lattice design and optimization. In addition to the discussion of this theory, the BALO/FLS calculation results are used to show that this theory can meet both speed and accuracy criteria of design as well as cover the large design range. Moreover, the results also show that two major perturbation issues in BWR lattice design and optimization, i.e., the large swing of average lattice enrichment and the thermal neutron black absorber's distribution as burnable poison can be resolved with the CMM perturbation theory. Finally, it is pointed out that the macro parameter perturbation combined with the micro parameter perturbation is extremely important to the accuracy.
