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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.
M. Dhandhang Purwadi, M. Tsuji, M. Narita, M. Itagaki
Nuclear Science and Engineering | Volume 129 | Number 1 | May 1998 | Pages 88-96
Technical Note | doi.org/10.13182/NSE98-A1966
Articles are hosted by Taylor and Francis Online.
A technique is presented for solving neutron diffusion equations with the boundary element method (BEM) based on a hierarchical domain decomposition technique. In this method, the reactor domain is decomposed into homogeneous regions and the boundary condition on the common boundary of regions is initially assumed. The neutron diffusion equation is solved iteratively at two levels of hierarchical structure: First, BEM is applied to solve the neutron diffusion equation of each homogeneous region under the given assumed boundary conditions and an assumed multiplication factor. Then, these assumed values are modified to satisfy the continuity conditions for the neutron flux and neutron current.The proposed technique is useful for multiregion problems with a large number of regions of complex geometry, where the finite difference approximation cannot be applied properly.
