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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.
Jang-Guen Park, Sung-Hee Jung, Jong Bum Kim, Jinho Moon, Chan Hyeong Kim
Nuclear Technology | Volume 192 | Number 2 | November 2015 | Pages 133-141
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT15-16
Articles are hosted by Taylor and Francis Online.
In industrial processes where multiphase flows are frequently encountered, it is important to examine the phase distribution and flow pattern to optimize process efficiency, safe operation, and cost savings. One of the most suitable techniques of industrial-process flow-dynamics visualization is the single photon emission computed tomography (SPECT) system, which provides, by means of a process-system-injected radioisotope source, cross-sectional images of the process flow. Obtaining reliable SPECT imaging results for a multiphase flow system, however, remains a significant challenge. In the present study, the use of a diverging collimator for improvement of industrial SPECT system performance is proposed. The advantages of the diverging-collimation industrial SPECT system as compared with a previous parallel-collimation version can be summarized as follows: (a) significant reduction of edge artifacts on a detection-efficiency map, and 19% improvement of average detection efficiency; (b) 36% improvement of image resolution; (c) accurate source region reconstruction even with the source positioned farther from the object’s center; and (d) a reduced system size.
