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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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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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NRC cuts fees by 50 percent for advanced reactor applicants
The Nuclear Regulatory Commission has announced it has amended regulations for the licensing, inspection, special projects, and annual fees it will charge applicants and licensees for fiscal year 2025.
Nicholas W. Touran, John C. Lee
Nuclear Science and Engineering | Volume 179 | Number 1 | January 2015 | Pages 85-103
Technical Paper | doi.org/10.13182/NSE13-85
Articles are hosted by Taylor and Francis Online.
We developed a simulation tool that accelerates the evaluation of design changes on the equilibrium cycle of fast-spectrum nuclear reactors. Within the tool, an implicit equilibrium cycle search is accelerated by a modal expansion perturbation method that expands arbitrary flux perturbations on a large basis of λ-eigenmode harmonics. The harmonics are computed only at the reference state using Krylov subspace iterative methods, and substantial perturbations from this state are shown to be well approximated by computationally efficient algebraic expressions. The modal expansion method is coupled to the equilibrium method to produce the later-in-time response of each design perturbation, resulting in an explicit perturbation-accelerated equilibrium cycle method. Because the method determines the perturbed flux explicitly, a wide variety of core performance metrics may be tracked within optimization frameworks, including the performance of thermal hydraulics, fuel, economics, core mechanical, and transients. This capability strongly differentiates the method from traditional generalized perturbation theory approaches. The motivating end-use of the method is to evaluate objective functions in multidisciplinary optimization of advanced reactor designs, though many other applications are envisioned.