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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Deep Fission raises $30M in financing
Since the Department of Energy kicked off a 10-company race with its Nuclear Reactor Pilot Program to bring test reactors on line by July 4, 2026, the industry has been waiting for new headlines proclaiming progress. Aalo Atomics broke ahead of the pack first by announcing last week that it had broken ground on its 50-MWe Aalo-X at Idaho National Laboratory.
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.