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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.
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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.
R. N. Hwang
Nuclear Science and Engineering | Volume 56 | Number 2 | February 1975 | Pages 119-130
Technical Paper | doi.org/10.13182/NSE75-A26651
Articles are hosted by Taylor and Francis Online.
This paper describes some general characteristics of the uncertainties in various fast-reactor parameters as a function of the corresponding uncertainties in nuclear data on the basis of statistical theory. By using the variational formalism, it is possible to relate the mean-square deviation of any reactivity coefficient (or reaction-rate ratio) to the covariance matrix of cross sections. The qualitative behavior of the uncertainties in fast-reactor parameters can be best illustrated geometrically in terms of the region of tolerance. The latter is the volume bound by a “hyper-ellipsoid” surface specified by the designer’s tolerance limit, the coefficients characteristic of the type of parameter in the system under consideration, and the correlation matrix. Exploratory studies and graphical illustrations are given for some cases of practical interest.