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Nuclear Energy Strategy announced at CNA2026
At the Canadian Nuclear Association Conference (CNA2026) in Ottawa, Ontario, on April 29, Minister of Energy and Natural Resources Tim Hodgson announced that Natural Resources Canada (NRCan) is developing a new Nuclear Energy Strategy for the country. The strategy, which is slated to be released by the end of this year, will be based on four objectives: 1) enabling new nuclear builds across Canada, 2) being a global supplier and exporter of nuclear technology and services, 3) expanding uranium production and nuclear fuel opportunities, and 4) developing new Canadian nuclear innovations, including in both fission and fusion technologies.
Maria Pusa
Nuclear Science and Engineering | Volume 182 | Number 3 | March 2016 | Pages 297-318
Technical Paper | doi.org/10.13182/NSE15-26
Articles are hosted by Taylor and Francis Online.
The burnup equations can, in principle, be solved by computing the exponential of the burnup matrix. However, the problem is extremely stiff, and the matrix exponential solution was long considered infeasible for entire burnup systems containing short-lived nuclides. After discovering that the eigenvalues of burnup matrices are confined to the vicinity of the negative real axis, the Chebyshev rational approximation method (CRAM) was introduced for solving the burnup equations and it was shown to be capable of providing accurate and efficient solutions without the need to exclude the short-lived nuclides. The main difficulty in using CRAM is determining the coefficients of the rational approximant for a given approximation order, with the previously published coefficients enabling only approximations up to order 16 for computing the matrix exponential. In this paper, a Remez-type method is presented for the computation of higher-order CRAM approximations. The optimal form of CRAM for the solution of burnup equations is discussed, and the method of incomplete partial fractions is proposed for this purpose. The CRAM coefficients based on this factorization are provided for approximation orders 4, 8, 12, . . ., 48. The accuracy of the method is demonstrated by applying it to large burnup and decay systems. It is shown that higher-order CRAM can be used to solve the burnup equations accurately for time steps of the order of 1 million years.