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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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Hanford looks inside sealed nuclear reactors using modern technology
A new imaging technology is being used on decommissioned reactors at the Department of Energy's Hanford Site in Washington state, revealing a detailed look inside the sealed enclosures.
W. Bennett, R. G. McClarren
Nuclear Science and Engineering | Volume 199 | Number 1 | April 2025 | Pages S808-S817
Research Article | doi.org/10.1080/00295639.2024.2333092
Articles are hosted by Taylor and Francis Online.
Verification solutions for uncertainty quantification (UQ) are presented for time-dependent transport problems where , the scattering ratio, is uncertain. The method of polynomial chaos expansions is employed for quick and accurate calculation of the quantities of interest (QoIs), and uncollided solutions are used to treat part of the uncertainty calculation analytically. We find that approximately six moments in the polynomial expansion are required to represent the solutions to these problems accurately. Additionally, the results show that if the uncertainty interval spans c = 1, which means it is uncertain whether the system is multiplying or not, the confidence interval will grow in time. Finally, since the QoI is a strictly increasing function, the percentile values are known and can be used to verify the accuracy of the expansion. These results can be used to test UQ methods for time-dependent transport problems.