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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.
Kiyonobu Yamashita, Isao Murata, Ryuichi Shindo
Nuclear Science and Engineering | Volume 110 | Number 2 | February 1992 | Pages 177-185
Technical Notes | doi.org/10.13182/NSE92-A23887
Articles are hosted by Taylor and Francis Online.
The accuracy of the nuclear design code system for the High-Temperature Engineering Test Reactor (HTTR) is evaluated for the neutronic characteristics that depend on core temperature by analyzing the overall temperature coefficients of reactivity and the effective multiplication factors obtained by an experiment in which the Very High Temperature Reactor Critical Assembly (VHTRC) is heated from ambient temperature to 200°C. The core of the VHTRC consists of block-type fuel containing low-enriched uranium (LEU). The nuclear design code system for the HTTR includes the DELIGHT, TWOTRAN-2, and CITATION-1000VP computer codes. The DELIGHT code is a one-dimensional cell burnup code developed to evaluate the nuclear characteristics of HTTR fuel and to calculate the group constants. The calculated overall temperature coefficients of reactivity between ambient temperature and 200°C agree well with the measured coefficients, and the calculated effective multiplication factors for different temperatures agree with measured factors within an uncertainty of 0.6%. From the results, it is concluded that the nuclear design code system for the HTTR predicts well the temperature-dependent neutronic characteristics of a core containing LEU fuel.
