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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.
Yoshiko Harima, Yukio Sakamoto, Naohiro Kurosawa, Akinao Shimizu
Nuclear Technology | Volume 168 | Number 3 | December 2009 | Pages 861-866
Shielding | Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (PART 3) / Radiation Protection | doi.org/10.13182/NT09-A9319
Articles are hosted by Taylor and Francis Online.
The geometric-progression (G-P) formula can accurately reproduce buildup factor data up to depths of 40 mean free paths (mfp) within a few percent. This formula was improved to apply to depths up to 100 mfp, using the buildup factor data of Shimizu et al. (2004) calculated with the Invariant Embedding method.The behavior of the K parameter as a function of distance was examined, and a new formula was introduced from the depth of Xm ([approximately]40 mfp). The fitting parameters were determined using a minimizing procedure of the maximum fractional deviation (MMD). Within some sets of parameters determined by the MMD fit, one set of parameters was selected that realized the interpolation of the buildup factor with regard to energy, using interpolated G-P parameters. Consequently, discrete buildup factor data were converted to continuous data with regard to both energy and distance.
