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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 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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ANS joins others in seeking to discuss SNF/HLW impasse
The American Nuclear Society joined seven other organizations to send a letter to Energy Secretary Christopher Wright on July 8, asking to meet with him to discuss “the restoration of a highly functioning program to meet DOE’s legal responsibility to manage and dispose of the nation’s commercial and legacy defense spent nuclear fuel (SNF) and high-level radioactive waste (HLW).”
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.