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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.
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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
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.
Jeffrey A. Favorite
Nuclear Science and Engineering | Volume 155 | Number 2 | February 2007 | Pages 321-329
Technical Paper | Mathematics and Computation, Supercomputing, Reactor Physics and Nuclear and Biological Applications | doi.org/10.13182/NSE07-A2666
Articles are hosted by Taylor and Francis Online.
Standard variational estimates for perturbations in inhomogeneous transport problems were applied to internal-interface perturbations in coupled neutron-photon problems. Absolute gamma-ray line leakages and ratios of line leakages were the quantities of interest. Gamma-ray spectroscopy using the deterministic multigroup discrete-ordinates code PARTISN was accomplished with a 130-group neutron library and a 120-group photon library with narrow bins centered around gamma lines of interest. Perturbed integrals were evaluated using a volume and a surface formulation, and issues involving negative fluxes (required in the adjoint calculation for line ratios) were addressed. Numerical test problems used a 252Cf source surrounded by a material containing nitrogen and hydrogen; the thickness of this material was perturbed ±86%. The ratios of the 1.8848-, 2.2246-, and 5.2692-MeV thermal neutron capture lines were very well estimated using the variational estimates, even for macroscopic-size perturbations of internal interface locations; the volume-integral formulation for the perturbed integrals was generally more accurate than the surface-integral formulation for estimating ratios. For estimating absolute leakages, the Roussopolos functional in the surface-integral formulation was clearly superior when the gamma-producing shell was thickened, but it produced negative estimates when the shell was thinned.