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Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
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.
A. M. Christie, C. G. Poncelet
Nuclear Science and Engineering | Volume 51 | Number 1 | May 1973 | Pages 10-24
Technical Paper | doi.org/10.13182/NSE73-A23253
Articles are hosted by Taylor and Francis Online.
The control of spatial xenon-induced oscillations in large power reactors is considered from the point of view of practical operator manual control. A control strategy is developed based on control theory concepts and considerations of the physics of the problem. It is shown that oscillations can be eliminated by a simple control action consisting of positioning a control rod in a specified location for a specified length of time; upon retrieval of the control rod to its equilibrium position, the flux, xenon and iodine distributions will have returned to equilibrium conditions. A control equation is derived from which the control rod insertion time and the duration of control can be calculated. For large pressurized water reactors of current and anticipated designs, control rod insertion times are in the range from one to four hours before the peak in the oscillation, while control times vary from one-half to two hours. Digital diffusion theory simulations are described which tend to verify the control concepts developed in the paper. Constraints in local power peaking are introduced by considering control at off-optimal times. The study provides guidelines for operator control which is near optimal in the sense that control actions are minimized in number and are most effective in terms of eliminating the oscillation.