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Division Spotlight
Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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!
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Latest News
Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
S. Varet, P. Dossantos-Uzarralde, N. Vayatis
Nuclear Science and Engineering | Volume 179 | Number 4 | April 2015 | Pages 398-410
Technical Paper | doi.org/10.13182/NSE14-07
Articles are hosted by Taylor and Francis Online.
For evaluated nuclear cross-section uncertainties, most standard approaches are based on experimental cross-section measurements, reflecting that these measurements have uncertainty on their own and, in particular, undetermined correlations. We propose here focusing on the estimation of experimental covariances and bypassing the direct empirical estimator, which cannot be used due to the small amount of available data. Because of the nonlinearity of experimental cross sections, an alternative method to the classical propagation error formula is presented. This method exploits a regression model of the experimental cross sections to generate pseudomeasurements and thereby allows an empirical estimation of experimental covariances. Moreover, thanks to a bootstrap, a quality measure for the estimation is provided. The empirical matrix estimation is then improved with shrinkage. The validity of the approach is confirmed through numerical experiments on a toy model. Finally, the procedure is applied to the real case of the 5525Mn nucleus.