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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.
Junli Li, Shenjin Ming, Yanfeng Cao, Yanli Deng
Nuclear Technology | Volume 168 | Number 2 | November 2009 | Pages 391-398
Shielding | Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection | doi.org/10.13182/NT09-A9215
Articles are hosted by Taylor and Francis Online.
The X-ray container/vehicle inspection system is a large and complex radiation application facility. To evaluate and optimize the shielding design for the system, a Monte Carlo method including two-step simulation, biasing sampling, and a scattering flag technique has been used to perform the shielding analysis - instead of the traditional empirical formula calculation.When the Monte Carlo method is applied to a complicated large system, some special techniques shall be used to obtain high accuracy and high efficiency in calculation. A special Monte Carlo method based on Geant4, including two-step simulation, biasing sampling, and scattering flag techniques, has been developed in this paper. For the two-step simulation, the first step is to simulate the electron transport inside the tungsten target of a linac and generate X-ray photons; the second step is to simulate the X-ray photon transport in the inspection system. For the biasing sampling, only the photons inside the X-ray beam are simulated and tracked. This allows more photons to reach the inspection system boundary. For the scattering flag, the trace of every photon reaching the inspection system boundary is recorded and stored, thus providing the possibility to tag the main dose contributors to the system boundary and allowing optimization of the shielding design.The simulation results on the inspection system boundary agree well with the measured results, and the key radiation contributors to the radiation dose on the system boundary are found with the scattering flag technique.A special Monte Carlo method combined with two-step simulation, biasing sampling and scattering flag techniques, has been developed and successfully used in the shielding design and optimization in an X-ray container/vehicle inspection system.
