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Division Spotlight
Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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Utility Working Conference and Vendor Technology Expo (UWC 2022)
August 7–10, 2022
Marco Island, FL|JW Marriott Marco Island
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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Unapologetically Pronuclear
Steven Arndtpresident@ans.org
By the time you read this, I will have celebrated my 41st anniversary as a member of the American Nuclear Society. In thinking about this time, I find myself realizing that I have never been part of anything else (besides my immediate family) for as long. I joined ANS when I started graduate school and have been an active member ever since. In that time, I have worked for several employers, been active in other professional and social organizations, lived in four different states, and worked on projects that have taken me all over the world—but my ties to ANS and the people I have met here have been the most influential I have ever known. In thinking about this, I can only come to one conclusion: there is something special about ANS. Is it the technology? The people? For me, it is both.
Maria Pusa
Nuclear Science and Engineering | Volume 169 | Number 2 | October 2011 | Pages 155-167
Technical Paper | dx.doi.org/10.13182/NSE10-81
Articles are hosted by Taylor and Francis Online.
The topic of this paper is solving the burnup equations using dedicated matrix exponential methods that are based on two different types of rational approximation near the negative real axis. The previously introduced Chebyshev Rational Approximation Method (CRAM) is now analyzed in detail for its accuracy and convergence, and correct partial fraction coefficients for approximation orders 14 and 16 are given to facilitate its implementation and improve the accuracy. As a new approach, rational approximation based on quadrature formulas derived from complex contour integrals is proposed, which forms an attractive alternative to CRAM, as its coefficients are easy to compute for any order of approximation. This gives the user the option to routinely choose between computational efficiency and accuracy all the way up to the level permitted by the available arithmetic precision. The presented results for two test cases are validated against reference solutions computed using high-precision arithmetics. The observed behavior of the methods confirms the previous conclusions of CRAM's excellent suitability for burnup calculations and establishes the quadrature-based approximation as a viable and flexible alternative that, like CRAM, has its foundation in the specific eigenvalue properties of burnup matrices.