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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.
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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.
Keiichi Saito
Nuclear Science and Engineering | Volume 37 | Number 3 | September 1969 | Pages 380-396
Technical Paper | doi.org/10.13182/NSE69-A19114
Articles are hosted by Taylor and Francis Online.
Input-noise sources in at-power reactors are formulated under the basic assumption that a set of macrostochastic variables characterizing the state of the reactors has Markoffian properties. An input-noise source is defined as the ratio between the power-spectral density of fluctuations in the reactor-power level and the square modulus of the source-transfer function. Random birth and death processes of neutrons give rise to a “white” contribution to the input source. Additional contributions are found which have the break (roll-off) angular frequencies determined by the relaxation time constants of the feedback effects on reactivity. These “non-white” terms come from fluctuations in neutron-reaction cross sections caused by temperature variations. The ratio of the non-white to the white terms increases as the reactor power increases. It also depends on the magnitude of the reactivity coefficients of feedback. Before one evaluates the magnitude of the non-white noise term, however, there should be knowledge of some statistical parameters relating the noise to random emission of energy by nuclear fissions, random exchange between the fuel and the coolant in heat transfer reactions and random removal through the coolant flow. The formula for analyzing the power-spectral density of the temperature fluctuations is also derived where the same unknown statistical parameters appear. Measurements of both the power and the temperature fluctuations will serve to determine these parameters whereby one will be able to obtain better information on the time constant and the reactivity coefficient of each feedback effect.