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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
Standards Program
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.
Yasunori Yamamura
Nuclear Science and Engineering | Volume 58 | Number 3 | November 1975 | Pages 328-331
Technical Note | doi.org/10.13182/NSE75-A26782
Articles are hosted by Taylor and Francis Online.
The macroscopic representation of complicated moderating processes has been investigated to describe the collision integral in the Legendre polynomial expansion of the neutron transport equation in terms of the macroscopic moderating parameter, defined as the ratio of the l'th-order Legendre component of the slowing-down density to the corresponding collision integral. This approach is similar in form to the Wigner-type continuous slowing-down theory, but the present moderating parameter is a function of lethargy, space, and time. For practical applications a new Greuling-Goertzel approximation is proposed based on the factorization of the angular flux. The present parameter, γl(u), is defined so as to compensate the difference between the lethargy spectrum of the space- and time-independent flux and the exact spectrum.