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Division Spotlight
Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
Meeting Spotlight
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, Jaakko Leppänen
Nuclear Science and Engineering | Volume 164 | Number 2 | February 2010 | Pages 140-150
Technical Paper | dx.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.