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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
Meeting Spotlight
2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
Standards Program
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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Latest News
Tank waste operations resume at Idaho’s IWTU
The Department of Energy’s Office of Environmental Management announced yesterday that waste processing operations have resumed at the Integrated Waste Treatment Unit (IWTU) at the Idaho National Laboratory Site. The resumption of operations follows the completion of two maintenance campaigns at the radioactive liquid waste treatment facility.
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.