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Division Spotlight
Nuclear Nonproliferation Policy
The mission of the Nuclear Nonproliferation Policy Division (NNPD) is to promote the peaceful use of nuclear technology while simultaneously preventing the diversion and misuse of nuclear material and technology through appropriate safeguards and security, and promotion of nuclear nonproliferation policies. To achieve this mission, the objectives of the NNPD are to: Promote policy that discourages the proliferation of nuclear technology and material to inappropriate entities. Provide information to ANS members, the technical community at large, opinion leaders, and decision makers to improve their understanding of nuclear nonproliferation issues. Become a recognized technical resource on nuclear nonproliferation, safeguards, and security issues. Serve as the integration and coordination body for nuclear nonproliferation activities for the ANS. Work cooperatively with other ANS divisions to achieve these objective nonproliferation policies.
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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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
Louis M. Shotkin, David L. Hetrick, Theodore R. Schmidt
Nuclear Science and Engineering | Volume 42 | Number 1 | October 1970 | Pages 10-15
Technical Paper | doi.org/10.13182/NSE70-A19321
Articles are hosted by Taylor and Francis Online.
In a reactor with feedback linearly proportional to the power level, the delayed neutrons permit the existence of unstable limit cycles. This means that, for linearly stable systems, the delayed neutrons can cause the system to become unstable for large enough disturbances. We demonstrate this analytically when the frequency of the limit cycle is near to the linear critical frequency. General criteria, based on the feedback transfer function, are given for the necessary existence of periodic solutions. Techniques for determining the stability of these periodic solutions are then shown. Examples are given for several reactor models.
