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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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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
William E. Kastenberg, Paul L. Chambré
Nuclear Science and Engineering | Volume 31 | Number 1 | January 1968 | Pages 67-79
Technical Paper | doi.org/10.13182/NSE68-A18009
Articles are hosted by Taylor and Francis Online.
The spatial and temporal behavior of neutron distributions governed by the nonlinear diffusion equation approximation to neutron transport theory are considered in this paper. Stability criteria for the equilibrium states of various reactor feedback models are determined by the method of comparison functions. The comparison functions are used to construct simple solutions with error bounds to the equations considered. The two reactor models considered are the prompt feedback and the adiabatic model. The stability of the equilibrium state was found to be governed by the generalized buckling κ and its relationship to μ the lowest eigenvalue of the associated linear Helmholtz equation. Negative feedback is considered in both cases. Since the comparison functions bound the true solution from above and below, one can determine absolute errors of the approximations involved when constructing solutions. In a similar fashion, a bound on the maximum value of the excursion can also be obtained with little extra effort.