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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.
Dimitar Altiparmakov
Nuclear Science and Engineering | Volume 175 | Number 3 | November 2013 | Pages 239-249
Technical Paper | doi.org/10.13182/NSE12-71
Articles are hosted by Taylor and Francis Online.
This paper presents an extension of the equivalence principle to allow distributed resonance self-shielding in a multiregion fuel configuration. Rational expansion of fuel-to-fuel collision probability is applied to establish equivalence between the actual fuel configuration and a homogeneous mixture of hydrogen and resonant absorber, which is a commonly used model to calculate library tables of resonance integrals. The main steps in the derivation are given along with the basic physics assumptions on which the presented approach relies. The method has been implemented in the WIMS-AECL lattice code and is routinely used for calculation of CANDU-type reactor lattices. Its capabilities are illustrated by comparison of WIMS-AECL and MCNP results of 238U resonance capture in a CANDU lattice cell. To determine the optimal rational expansion of the fuel-to-fuel collision probability, the calculations were carried out by varying the number of rational terms from one to six. The results show that four terms are sufficient. Further increase of the number of terms affects the computing time, while the effect on accuracy is negligible. To illustrate the convergence of the results, the fuel subdivision is gradually refined varying the number of fuel pin subdivisions from 1 to 32 equal-area annuli. The results show very good agreement with the reference MCNP calculation.
