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Aerospace Nuclear Science & Technology
Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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
DOE extends Centrus’s HALEU production contract by one year
Centrus Energy has announced that it has secured a contract extension from the Department of Energy to continue—for one year—its ongoing high-assay low-enriched uranium (HALEU) production at the American Centrifuge Plant in Piketon, Ohio, at an annual rate of 900 kilograms of HALEU UF6. According to Centrus, the extension is valued at about $110 million through June 30, 2026.
Tsutomu Hoshino*
Nuclear Science and Engineering | Volume 49 | Number 1 | September 1972 | Pages 59-71
Technical Paper | doi.org/10.13182/NSE72-A22527
Articles are hosted by Taylor and Francis Online.
The optimization of the multistage refueling decision process was studied by the heuristic approach for four-region batch refueling including shuffling. The current state of the process is assumed to be well characterized by so called heuristic features, as excess reactivity or peaking factor. The features are summed up with each weight, defining the decision evaluation function which should be maximized at each refueling by the best decision. Thus the final criterion, i.e., the average discharge burnup at the end of the whole reactor life can be regarded as a function of the weight and is maximized in the weight space by the hill climbing algorithm. The approach can also be interpreted as an attempt to determine, through learning, the general importances of the rules of thumb in the refueling policy as maximization of the excess reactivity or power flattening. A numerical simulation is given, and the maximum burnup, the refueling scheme, and the optimal weight are discussed in relation to the power-peaking factor constraint. Though the method is not guaranteed as for the optimality, reasonable solutions are obtained and the intuitive understanding of the process is possible by discussing the optimum weight of each rule.