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Division Spotlight
Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
Meeting Spotlight
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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Latest News
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.
D. G. Cacuci, J.J. Wagschal, A. Yaari
Nuclear Science and Engineering | Volume 81 | Number 3 | July 1982 | Pages 443-450
Technical Paper | doi.org/10.13182/NSE82-A20285
Articles are hosted by Taylor and Francis Online.
The concept of a leakage importance function is introduced and analyzed for physical systems governed by the Boltzmann transport equation. The homogeneous equation with inhomogeneous boundary conditions satisfied by the importance function is derived by using adjoint operators. A standard discrete ordinates transport code is used to solve this equation, and some important numerical aspects are highlighted. Idealized nuclear systems are analyzed to illustrate that the leakage importance function gives a measure of the relative importance of each source particle in phase space in contributing to the leakage, and that the leakage importance function provides insight regarding the specific physical process that leads to leakage.