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Division Spotlight
Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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
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.
Ronald W. Badgley, Robert E. Uhrig
Nuclear Science and Engineering | Volume 19 | Number 2 | June 1964 | Pages 158-163
Technical Paper | doi.org/10.13182/NSE64-A28904
Articles are hosted by Taylor and Francis Online.
The power spectral density of the neutron density of a reactor is frequency dependent and related to the reactor transfer function and the power spectral density of the input disturbance. For a critical reactor, a power-spectral-density measurement can be used to evaluate the ratio (β/) where β is the effective delayed-neutron fraction and the effective neutron lifetime. For subcritical operation, an evaluation of the reactor shutdown margin can be obtained by determining the quantity where k, the effective reproduction constant, can be determined if the effective neutron lifetime and effective delayed neutron fraction are known. The output power spectral density of the University of Florida Training Reactor, operating in the subcritical region, has been measured using a plutonium/beryllium source to provide the input disturbance. The data are then fitted by a least-squares method to a theoretical model to obtain the quantity