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Accelerator Applications
The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
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International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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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Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
Sumeet Chhibber, George E. Apostolakis, David Okrent
Nuclear Technology | Volume 105 | Number 1 | January 1994 | Pages 87-103
Technical Paper | Special on Nuclear Criticality Safety / Nuclear Reactor Safety | doi.org/10.13182/NT94-A34913
Articles are hosted by Taylor and Francis Online.
The use of expert judgments in probabilistic risk assessments has become common. Simple aggregation methods have often been used with the result that expert biases and interexpert dependence are often neglected. Sophisticated theoretical models for the use of expert opinions have been proposed that offer ways of incorporating expert biases and dependence, but they have not found wide acceptance because of the difficulty and rigor of these methods. Practical guidance on the use of the versatile Bayesian expert judgment aggregation model is provided. In particular, the case study of pressure increment due to vessel breach in the Sequoyah nuclear power plant is chosen to illustrate how phenomenological uncertainty can be addressed by using the Bayesian aggregation model. The results indicate that the Bayesian aggregation model is a suitable candidate model for aggregating expert judgments, especially if there is phenomenological uncertainty. Phenomenological uncertainty can be represented through the dependence parameter of the Bayesian model. This is because the sharing of assumptions by the experts tends to introduce dependence between the experts. The extent of commonality in the experts’ beliefs can be characterized by assessing their interdependence. The results indicate that uncertainty is possibly underestimated by ignoring dependence. Two Bayesian approaches are used. The first approach uses the experts’ opinions as evidence to update the decision maker’s state of knowledge. The second approach, in recognition of the fact that the experts are highly dependent on a common information source, assumes that the common information source is the actual expert and the participants are assessing its biases and credibility. The results lend validity to the use of weighted averaging schemes because the Bayesian aggregation method encompasses simple arithmetic and geometric averaging techniques.