ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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.
George Apostolakis, Ali Mosleh
Nuclear Science and Engineering | Volume 70 | Number 2 | May 1979 | Pages 135-149
Technical Paper | doi.org/10.13182/NSE79-A19646
Articles are hosted by Taylor and Francis Online.
A model for the evaluation of probabilities of rare events by combining the available experience with expert opinion is developed, using the core melt frequency of nuclear power reactors as an example. A distribution for this frequency is assessed using the statistical evidence and including “near misses.” This distribution is subsequently modified, via Bayes' theorem, to include the estimate derived by the Reactor Safety Study, which is treated as an expert's opinion. A probabilistic model for the credibility of this opinion that includes the critics' point of view is presented. The resulting (posterior) distribution is the assessed distribution of the frequency of reactor core melts based on a body of knowledge that includes the available experience and the WASH-1400 estimate.