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Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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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.
Stefano L. Paveri-Fontana, Harvey Amster
Nuclear Science and Engineering | Volume 44 | Number 1 | April 1971 | Pages 44-57
Technical Paper | doi.org/10.13182/NSE71-A18904
Articles are hosted by Taylor and Francis Online.
The double spherical harmonics method has hitherto been considered applicable only if two conditions are fulfilled: (a) the directions of the assumed angular discontinuities could be assigned a priori by symmetry, and (b) at every boundary surface, these directions lie in a tangent plane. In this paper, the DP-0 approximation is reformulated to cover all situations; for some new ones, the accuracy is predictably better than that from the P-1 approximation. The directions of the angular discontinuity now have to be calculated, but a straightforward generalization of the usual derivation fails to furnish such a procedure. This generalization also retains a former uncertainty about how much of a delta function is on each side of the angular discontinuity. A variational principle is used as one way to settle both of these issues. Anisotropic scattering is allowed. Remarkably, the completed formulation differs from ordinary diffusion theory, including boundary conditions, only in the definition of the diffusion coefficient. A standard diffusion theory calculation can accommodate whichever type of theory is preferred in any particular region of a single problem; the adjustment is made merely by assigning the corresponding diffusion coefficient there. The variational principle implies that the delta function should be divided evenly into two parts at the discontinuity. However, this division is not a mathematically inherent property of the delta function, as sometimes thought, and other formulations for spherical and cylindrical geometries have placed the delta function entirely in the forward hemisphere of directions. Examples showing superior accuracy and physical interpretations supported that choice, but they are matched here by other examples favoring different divisions.