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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.
G. C. Pomraning
Nuclear Science and Engineering | Volume 22 | Number 3 | July 1965 | Pages 328-338
Technical Paper | doi.org/10.13182/NSE65-A20937
Articles are hosted by Taylor and Francis Online.
An approximation to the transport equation is presented, which is capable of arbitrary accuracy and yields the exact transport-theory asymptotic behavior in all orders for any geometry. Anisotropic scattering is treated explicitly, and the inclusion of energy and time dependences is straightforward. The approximation, which is very similar to the usual spherical-harmonic (PN) method, is derived by introducing a new truncation scheme into the infinite set spherical-harmonic equations. This truncation method consists of assuming that the higher spherical-harmonic components, equated to zero in the PN method, can be related to lower components by assuming the angular distribution to be in an asymptotic distribution. The resulting approximation is very similar in structure to the PN approximation (in particular, it is no more complex) but has the added advantage of yielding exact asymptotic behavior.