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The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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.
Yasunori Yamamura
Nuclear Science and Engineering | Volume 61 | Number 3 | November 1976 | Pages 377-387
Technical Paper | doi.org/10.13182/NSE76-A26924
Articles are hosted by Taylor and Francis Online.
To estimate analytically the effects of discrete model and evaporation model inelastic scattering on the fast neutron spectrum, the original Greuling-Goertzel (GG) approximation was developed with the help of the generalized function theory. In place of the collision density function ψ(u), the two-term Taylor's expansion of a test function of a functional ψ was proposed to obtain analytic expressions of lethargy moments of inelastic scattering kernels. By using these moments, the author derived the standard GG approximation including all inelastic events. By introducing an approximate separable kernel of the evaporation model inelastic scattering, another conventional treatment of inelastic scatterings was proposed, i.e., the external source approximation of inelastic scattering. In this approximate method, elastic scattering was treated by the ordinary GG approximation. The present standard GG theory was useful for the preliminary description of fast neutron spectrum in a mixture in which a large amount of fuel elements is not included, while the external source approximation was shown to estimate reasonably the effects of inelastic scattering on fast neutron spectrum in any medium.