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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.
Yung-An Chao, Anthony Attard
Nuclear Science and Engineering | Volume 90 | Number 1 | May 1985 | Pages 40-46
Technical Paper | doi.org/10.13182/NSE85-A17429
Articles are hosted by Taylor and Francis Online.
The stiffness problem in reactor kinetics is overcome by the stiffness confinement method for solving the kinetic equations. The idea is based on the observation that the stiffness characteristic is present only in the time response of the prompt neutron density, but not in that of the delayed neutron precursors. The method is, therefore, devised to have the stiffness decoupled from the differential equations for precursors and confined to the one for the prompt neutrons, which can be analytically solved. Numerical examples of applying the method to a variety of problems confirm that the time step increment size can be greatly increased and that much computing time can be saved, as compared to other conventional methods. The theory is of general validity and involves no approximation other than the discretization of the time variable.