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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Latest News
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.
Ce Yi, Alireza Haghighat
Nuclear Science and Engineering | Volume 164 | Number 3 | March 2010 | Pages 221-247
Technical Paper | doi.org/10.13182/NSE09-110
Articles are hosted by Taylor and Francis Online.
In this paper, we present a hybrid formulation/algorithm to solve the linear Boltzmann equation, specifically for application to problems containing regions of low scattering. The hybrid approach uses the characteristics method in low scattering regions, while the remaining regions are treated with the discrete ordinates method (SN). A shared scattering kernel allows an arbitrary order of anisotropic scattering in both block-oriented solvers. A new three-dimensional transport code (TITAN) has been developed based on the hybrid approach. TITAN divides a problem model into coarse meshes (blocks) in the Cartesian geometry. The block-oriented structure allows different fine-meshing schemes (or characteristic ray densities) and angular quadrature sets for different coarse meshes. Angular and spatial projection techniques are developed to transfer angular fluxes on the interfaces of the coarse meshes. We have tested the performance and accuracy of the new hybrid algorithm within the TITAN code for a number of benchmark problems. The results of a computed tomography model and the Kobayashi benchmark problems are presented in this paper. It is demonstrated that while preserving high-level accuracy as compared to reference Monte Carlo simulations, the hybrid algorithm achieves significant computation efficiency as compared to the SN method only.
