ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Explore membership for yourself or for your organization.
Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
Standards Program
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!
Latest Magazine Issues
Jul 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
August 2025
Nuclear Technology
Fusion Science and Technology
Latest News
Sandia and Aeva evaluate intrusion detection system
Sandia National Laboratories is collaborating with the California-based Aeva Technologies, a developer of next-generation sensing and perception systems, on the development of technology for strengthening security at U.S. nuclear reactor sites.
Rei Kimura, Yuki Nakai, Satoshi Wada
Nuclear Science and Engineering | Volume 195 | Number 12 | December 2021 | Pages 1279-1290
Technical Paper | doi.org/10.1080/00295639.2021.1908081
Articles are hosted by Taylor and Francis Online.
A novel ex-core-detector–based core power reconstruction method is presented. The method uses power correlations between fuel regions and can be applied to a real-time small reactor core monitoring system especially for the detection of abnormal behavior. The use of ex-core detectors reduces the installation and maintenance costs of small modular reactors (SMRs) compared to conventional in-core detectors. To construct the power distribution with ex-core-detector count rates, it is necessary to account for the scattering and absorption reactions of neutrons within the core that make it difficult to extract information directly from the central core region. In the proposed method, detector responses and power correlations are preevaluated and revised by mathematical transformation. Monte Carlo simulations using the realistic SMR core design MoveluXTM demonstrated that the present method is capable of reconstructing the core power distributions within an average error of 10% using the count rates of the ex-core detectors. Also, the reconstruction successfully identified the position of abnormal power peaks in the central core region and an unbalanced power distribution.
