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Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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2027 ANS Winter Conference and Expo
October 31–November 4, 2027
Washington, DC|The Westin Washington, DC 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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ANS event on 3DEXPERIENCE platform, powered by virtual twin technology
The American Nuclear Society will be presenting the online Supplier Showcase “5 Critical Approaches to Accelerate Advanced Nuclear Enterprise Success with Digital Transformation” on Thursday, December 5, from 11:00 a.m. to 12:00 p.m. (EST). The session will be hosted by Dassault Systèmes.
Registration for the program, which is open to all, is required.
Maria Pusa, Jaakko Leppänen
Nuclear Science and Engineering | Volume 164 | Number 2 | February 2010 | Pages 140-150
Technical Paper | doi.org/10.13182/NSE09-14
Articles are hosted by Taylor and Francis Online.
The topic of this paper is the computation of the matrix exponential in the context of burnup equations. The established matrix exponential methods are introduced briefly. The eigenvalues of the burnup matrix are important in choosing the matrix exponential method, and their characterization is considered. Based on the characteristics of the burnup matrix, the Chebyshev rational approximation method (CRAM) and its interpretation as a numeric contour integral are discussed in detail. The introduced matrix exponential methods are applied to two test cases representing an infinite pressurized water reactor pin-cell lattice, and the numerical results are presented. The results suggest that CRAM is capable of providing a robust and accurate solution to the burnup equations with a very short computation time.