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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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DOE issues new NEPA rule and procedures—and accelerates DOME reactor testing
Meeting a deadline set in President Trump’s May 23 executive order “Reforming Nuclear Reactor Testing at the Department of Energy,” the DOE on June 30 updated information on its National Environmental Policy Act (NEPA) rulemaking and implementation procedures and published on its website an interim final rule that rescinds existing regulations alongside new implementing procedures.
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.