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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.
M. M. R. Williams
Nuclear Science and Engineering | Volume 173 | Number 2 | February 2013 | Pages 182-196
Technical Note | doi.org/10.13182/NSE12-11
Articles are hosted by Taylor and Francis Online.
A method has been developed that provides analytic solutions for two-dimensional cell problems for the neutron transport equation. This is made possible by assuming an infinite, repeating lattice of rectangular regions. The solution is effected by means of a finite Fourier transform, the periodicity of which is related to the size of the unit cell. In order to drive the flux, we assume that the cell is composed of two regions: an inner circular region and the remaining exterior part. Different sources are placed in each region thereby leading to a situation rather like the conventional reactor cell problem but with no spatial variation of the cross sections. The method is illustrated by two examples: the Levermore-Pomraning equations and the two-group equations. In the former case, we have obtained the stochastically averaged flux within the cell and also the Pomraning χ-function. In addition, we have calculated the ratio of the spatially averaged flux in the outer region to that in the inner circular region, i.e., the disadvantage factor. Fluxes and disadvantage factors are also obtained for the two-group equations, and the rate of convergence is shown. These results are exact transport theory solutions and are offered as benchmarks for checking transport theory codes. The calculations are also repeated using diffusion theory. The SPN method, which we show to be exact for our problem, is used to demonstrate the rate of convergence of the PN method for two-dimensional cell problems.