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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
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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.
Keiichi Saito
Nuclear Science and Engineering | Volume 48 | Number 4 | August 1972 | Pages 467-474
Technical Paper | doi.org/10.13182/NSE72-A22514
Articles are hosted by Taylor and Francis Online.
Lehto and Carpenter performed a set of experiments concerning the temperature and the gamma-ray fluctuations in a relatively low power reactor with high fission product inventories. The results are uniformly and quantitatively analyzed by applying the theoretical approach previously developed by the present author. The new features of the present consideration are the following two points: (a) incorporation of the external noise source in the previous theory which includes only the inherent noise source theoretically determined with the use of the first-order linearized Markoffian model of the reactor noise phenomenon; (b) analysis of the cross power spectral density (CPSD) between the two state quantities characterizing the core performances. The first point gives a successful interpretation of most of the experimental results in spite of adopting a simple analytical model. The newly extended framework of the theory can include also a reactivity transfer-function analysis with the use of a proper driving function. The phase of the CPSD between the power and the temperature is calculated on a one-space-point, a one-delayed-group, and a one- or two-feedback-loop reactor model. The results suggest that the experimental determination of the phase will provide both a check point for the theoretical model of the dynamical behaviors of at-power reactors and some bits of information on the feedback parameters.