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September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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The RAIN scale: A good intention that falls short
Radiation protection specialists agree that clear communication of radiation risks remains a vexing challenge that cannot be solved solely by finding new ways to convey technical information.
Earlier this year, an article in Nuclear News described a new radiation risk communication tool, known as the Radiation Index, or, RAIN (“Let it RAIN: A new approach to radiation communication,” NN, Jan. 2025, p. 36). The authors of the article created the RAIN scale to improve radiation risk communication to the general public who are not well-versed in important aspects of radiation exposures, including radiation dose quantities, units, and values; associated health consequences; and the benefits derived from radiation exposures.
Taewan Noh, Warren F. Miller, Jr.
Nuclear Science and Engineering | Volume 124 | Number 1 | September 1996 | Pages 18-30
Technical Paper | doi.org/10.13182/NSE96-A24221
Articles are hosted by Taylor and Francis Online.
Using the operator form of a synthetic acceleration, the P1 acceleration [diffusion synthetic acceleration (DSA)] and P2 acceleration schemes for one-dimensional slab and the P1 and simplified P2 acceleration schemes for two-dimensional x-y geometry are derived. The convergence rate of each scheme for a simple model problem is compared, and the result is generalized by performing a Fourier analysis. In the one-dimensional case, the new second-moment P2 acceleration outperforms an earlier third-moment P2 acceleration developed by Miller and Larsen. However, it is still less efficient than P1 acceleration. Similar results show that the P1 acceleration converges faster than the simplified P2 acceleration in two-dimensional x-y geometry. These results confirm that one cannot simply assume that replacement of the DSA method with a higher order operator will lead to a smaller spectral radius.