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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Hash Hashemian: Visionary leadership
As Dr. Hashem M. “Hash” Hashemian prepares to step into his term as President of the American Nuclear Society, he is clear that he wants to make the most of this unique moment.
A groundswell in public approval of nuclear is finding a home in growing governmental support that is backed by a tailwind of technological innovation. “Now is a good time to be in nuclear,” Hashemian said, as he explained the criticality of this moment and what he hoped to accomplish as president.
HyeongKae Park, Cassiano R. E. de Oliveira
Nuclear Science and Engineering | Volume 161 | Number 2 | February 2009 | Pages 216-234
Technical Paper | doi.org/10.13182/NSE161-216
Articles are hosted by Taylor and Francis Online.
This paper describes the development of a coupled space-angle a posteriori error analysis and adaptive method for radiation transport calculations based on the second-order, even-parity form of the transport equation discretized by a variational finite element-spherical harmonics method (FE-PN). Rigorous a posteriori error estimates for the global L2 norm in the even-parity angular flux are derived by utilizing duality arguments. Separate error components for the spatial and angular discretizations are obtained by the adaptive algorithm by first seeking convergence in the spatial variable and then by projecting the spatially converged solution onto the higher-order PN equation to estimate the angular truncation error. The validity of the developed coupled space-angle adaptive refinement strategy is assessed by comparing the developed error indicator with the true error for representative problems in one and two dimensions. The method of manufactured solutions and alternative transport solution methods are used to provide the true error. Comparisons indicate that the space-angle adaptivity framework is capable of guiding the FE-PN method toward the true solution.
