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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.
H. Rief, H. Kschwendt
Nuclear Science and Engineering | Volume 30 | Number 3 | December 1967 | Pages 395-418
Technical Paper | doi.org/10.13182/NSE67-A18401
Articles are hosted by Taylor and Francis Online.
A detailed Monte Carlo analysis in one, two, and three dimensions and with different multigroup scattering kernels is presented for a number of actual reactor systems. Several variance reducing sampling techniques, which we believe to be unusual, are employed and, in addition to the prediction of reactivity, much emphasis is placed on generation time calculations with reference to the “life cycle” point of view. One of the main points of interest in the numerical results obtained is the comparison of the reactivity and time eigenvalues with those obtained from the equivalent SN and jN calculations. The excellent agreement with these two methods establishes the necessary confidence in the Monte Carlo procedure described here. As a further illustration of the method, it was thought to be of interest to compare the numerical results obtained from different scattering kernels (transport approximation, linear anisotropy, and exact anisotropy) with a view to assessing the influence of these different approximations on the reactivity, absorption, leakage, generation time, etc. Simultaneously, an examination of two different Monte Carlo sampling techniques is presented. To apply a physical test to the method, some highly enriched uranium spheres, some cylinders of extreme geometry reflected by a variety of materials, and some cylindrical annuli were analyzed and the results compared with experiments. In addition, some systems requiring the full use of the three-dimensional scope of the method are studied. The efficiency of the Monte Carlo procedure is finally illustrated by listing, for several calculations, the probable errors in the reactor eigenvalues and other parameters after 10 min of IBM-7090 computer time. This analysis proves that statistical methods can be used to carry out threedimensional assessments of reactor assemblies with sufficient accuracy without the expenditure of a prohibitive amount of computer time. Such a goal has not yet been achieved by the numerical or analytical methods which solve the neutron transport equation.
