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Human Factors, Instrumentation & Controls
Improving task performance, system reliability, system and personnel safety, efficiency, and effectiveness are the division's main objectives. Its major areas of interest include task design, procedures, training, instrument and control layout and placement, stress control, anthropometrics, psychological input, and motivation.
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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
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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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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.
Kirk A. Mathews
Nuclear Science and Engineering | Volume 132 | Number 2 | June 1999 | Pages 155-180
Technical Paper | doi.org/10.13182/NSE99-A2057
Articles are hosted by Taylor and Francis Online.
Discrete ordinates calculations are presumed to translate particles from cell to cell in the directions specified in the angular set. This should result in uncollided particles from a small source propagating through the spatial mesh in narrow beams in these directions. Accurate high-order angular quadratures presume accurately attenuated propagation in the intended directions. This work examines the ability of various spatial quadratures to propagate rays correctly. Some widely used methods are shown to fail at this fundamental task. Diamond-difference approximations introduce undamped lateral oscillations, resulting in severely unphysical flux representations. Nonlinear fixups can prevent negativity but do not correct the underlying failure to properly propagate rays. First-moment conserving schemes tend to be successful but can be degraded in performance by simplifying approximations that are often used. Characteristic schemes are shown to have significant advantages. New characteristic methods are developed here that are exact (in a certain sense) in propagating rays and that uncouple the calculation of adjacent spatial cells in the mesh sweep. This enables DO loops to be converted to DO INDEPENDENT loops, with obvious implications for vector and/or parallel implementations.