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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
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.
John R. Travis, Francis H. Harlow, Anthony A. Amsden
Nuclear Science and Engineering | Volume 61 | Number 1 | September 1976 | Pages 1-10
Technical Paper | doi.org/10.13182/NSE76-A28455
Articles are hosted by Taylor and Francis Online.
The theoretical study of time-varying two-phase flow problems in several space dimensions introduces such a complicated set of coupled nonlinear partial differential equations that numerical solution procedures for a high-speed computer are required in almost all but the simplest examples. Efficient attainment of realistic solutions for practical problems requires a finite difference formulation that is simultaneously implicit in the treatment of mass convection, equations-of-state, and the momentum coupling between phases. We describe such a method, discuss the equations on which it is based, and illustrate its properties by means of examples. In particular, we emphasize the capability for calculating physical instabilities and other time-varying dynamics, at the same time avoiding numerical instability. The computer code is applicable to problems in reactor safety analysis, the dynamics of fluidized dust beds, raindrops or aerosol transport, and a variety of similar circumstances, including the effects of phase transitions and the release of latent heat or chemical energy.