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Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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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.
W. R. Rhyne, A. C. Lapsley
Nuclear Science and Engineering | Volume 40 | Number 1 | April 1970 | Pages 91-100
Technical Paper | doi.org/10.13182/NSE70-A18881
Articles are hosted by Taylor and Francis Online.
A numerical method for the solution of the time- and space-dependent multigroup diffusion equations is presented. The method permits a significant reduction in the computer time required to solve these equations by substantially increasing the allowable time step size. In the point reactor case, a form of the method considerably simplifies the calculation by removing the explicit dependence on the generation time and the delayed-neutron terms. The space-time equations are transformed into the Laplace domain and after multiplication by a weighting function they are transformed back into the time domain. By appropriate choice of the weighting function the equations appear either as coupled convolution integrals, where numerically difficult (e.g., generation time and delayed neutron) terms have been canceled, or as coupled integral equations in the weighted residual form, which permits very large time steps to be taken.