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Mathematics & Computation
Division members promote the advancement of mathematical and computational methods for solving problems arising in all disciplines encompassed by the Society. They place particular emphasis on numerical techniques for efficient computer applications to aid in the dissemination, integration, and proper use of computer codes, including preparation of computational benchmark and development of standards for computing practices, and to encourage the development on new computer codes and broaden their use.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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
First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
V. Jagannathan, R. P. Jain, Vinod Kumar, H. C. Gupta, P. D. Krishnani
Nuclear Science and Engineering | Volume 104 | Number 3 | March 1990 | Pages 222-238
Technical Paper | doi.org/10.13182/NSE90-A23722
Articles are hosted by Taylor and Francis Online.
A diffusion iterative scheme has been developed to analyze the basic three-dimensional supercell problem encountered in pressurized heavy water reactors (PHWRs). Multigroup transport calculations are performed essentially in one dimension for the fuel cluster cell and the reactivity device (RD) supercell problems. Iterative diffusion calculations are done in one and two dimensions such that the net transport leakages into the fuel cluster or RD are reproduced. The few-group parameters of the fuel cluster or the boundary conditions on the RD surface are modified for this purpose. With these modifications, the three-dimensional supercell problem is treated by diffusion theory. The accuracy of the new scheme is demonstrated against the corresponding transport solutions in both one and three dimensions. A half-bundle-sized constant mesh is proposed for core diffusion analyses. Since the RDs in a PHWR are rather arbitrarily located, it is difficult to perturb the lattice parameters of controlled meshes properly when a constant mesh size is employed. A flux-related weighting scheme is devised to distribute the δ∑’s in meshes falling within the zone of influence of an RD. This core model is compared with a direct method where the supercell concept is avoided and RDs are simulated by internal boundary conditions directly in the core diffusion simulation. Analysis of certain low-power criticals provides the experimental validation of the calculational schemes.