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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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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.
Kosuke Aizawa, Kaoru Fujita, Hideki Kamide, Naoto Kasahara
Nuclear Technology | Volume 189 | Number 2 | February 2015 | Pages 111-121
Technical Paper | Fission Reactors | doi.org/10.13182/NT13-156
Articles are hosted by Taylor and Francis Online.
The Japan Sodium-cooled Fast Reactor (JSFR) is studied as an advanced loop-type sodium-cooled reactor. A selector-valve (SV) mechanism is adopted in the design of JSFR for its failed fuel detection and location (FFDL) system. JSFR has only two FFDL units for 562 core fuel subassemblies to reduce construction cost by decreasing the reactor vessel diameter. Consequently, one SV-FFDL unit must handle about 300 subassemblies. Because of the large number of subassemblies per unit, it is predicted that the total duration for measuring all the fuel subassemblies becomes long. In addition, JSFR adopts an upper internal structure (UIS) with a slit above the core. In order to detect the fission products from the subassemblies below the slit, additional sampling nozzles for the FFDL are set in the UIS around the slit. In previous water experiments and numerical simulation, the sampling performance for the subassemblies under the UIS slit has been evaluated to be lower than those under the normal UIS position. In this paper, the outline of the FFDL system is shown, which can be applied to a large number of fuel subassemblies in a compact reactor vessel. The detection capability of the FFDL system was studied to achieve the design conditions. Operation modes and procedures of the FFDL system were also investigated.
