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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.
M. M. R. Williams
Nuclear Science and Engineering | Volume 174 | Number 2 | June 2013 | Pages 172-178
Technical Paper | doi.org/10.13182/NSE12-45
Articles are hosted by Taylor and Francis Online.
A new approach is developed for solving stochastic eigenvalue problems that arise when uncertainty is present in the cross-section data in a critical assembly. The method has been shown to agree with values obtained from a direct quadrature. The new approach, which uses a polynomial chaos expansion (PCE), does not involve the nonlinear equations associated with the classical method of PCE, but rather a linear equation obtained by considering an equivalent time-dependent problem; it therefore leads to much simpler calculational procedures. The convergence of the method is rapid, and it is illustrated by numerical examples based upon a criticality problem and also by comparison with a problem that uses the nonlinear method.