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Conference Spotlight
2025 ANS Winter Conference & Expo
November 8–12, 2025
Washington, DC|Washington Hilton
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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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Japan gets new U for enrichment as global power and fuel plans grow
President Trump is in Japan today, with a visit with new Prime Minister Sanae Takaichi on the agenda. Takaichi, who took office just last week as Japan’s first female prime minister, has already spoken in favor of nuclear energy and of accelerating the restart of Japan’s long-shuttered power reactors, as Reuters and others have reported. Much of the uranium to power those reactors will be enriched at Japan’s lone enrichment facility—part of Japan Nuclear Fuel Ltd.’s Rokkasho fuel complex—which accepted its first delivery of fresh uranium hexafluoride (UF₆) in 11 years earlier this month.
A. Z. Akcasu, A. Dalfes
Nuclear Science and Engineering | Volume 8 | Number 2 | August 1960 | Pages 89-94
Technical Paper | doi.org/10.13182/NSE60-A25783
Articles are hosted by Taylor and Francis Online.
The question of nonlinear stability of stationary reactor systems is investigated by two methods. The first method is analytic and sets the theory of nonlinear stability on a firm mathematical basis. The second method makes use of an electrical analogy and is based on the stability criterion stated by Weinberg and Ergen for nonlinear mechanical systems. Both methods deal with reactor systems in which feedback may be nonlinear as well as linear. The effect of delayed neutrons is included in the treatment. The stability conditions previously derived by others are shown to be special cases of the criteria proposed in this paper.
