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Division Spotlight
Decommissioning & Environmental Sciences
The mission of the Decommissioning and Environmental Sciences (DES) Division is to promote the development and use of those skills and technologies associated with the use of nuclear energy and the optimal management and stewardship of the environment, sustainable development, decommissioning, remediation, reutilization, and long-term surveillance and maintenance of nuclear-related installations, and sites. The target audience for this effort is the membership of the Division, the Society, and the public at large.
Meeting Spotlight
Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
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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Fusion Science and Technology
Latest News
Taking shape: Fusion energy ecosystems built with public-private partnerships
It’s possible to describe fusion in simple terms: heat and squeeze small atoms to get abundant clean energy. But there’s nothing simple about getting fusion ready for the grid.
Private developers, national lab and university researchers, suppliers, and end users working toward that goal are developing a range of complex technologies to reach fusion temperatures and pressures, confounded by science and technology gaps linked to plasma behavior; materials, diagnostics, and electronics for extreme environments; fuel cycle sustainability; and economics.
Hyung Jin Shim, Chang Hyo Kim
Nuclear Science and Engineering | Volume 157 | Number 2 | October 2007 | Pages 132-141
Technical Paper | doi.org/10.13182/NSE06-33
Articles are hosted by Taylor and Francis Online.
Two new stopping criteria designed to terminate automatically inactive cycle runs in Monte Carlo (MC) neutronics eigenvalue calculations are derived in terms of the covariance matrix of stochastic error components inherent in the stationary fission source distribution (FSD) from each stationary MC cycle run. A practical way to determine the covariance matrix using nonstationary FSD in the course of inactive cycle MC runs is presented. The effectiveness of the new stopping criteria including the way to calculate the covariance matrix is examined through continuous energy MC neutronics calculations for ten pressurized water reactor test problems with varying dominance ratios. It is shown that the empiricism-free new stopping criteria stop inactive cycle MC runs effectively and that FSDs from the termination of inactive MC runs are stationary consistent with the available posterior source convergence diagnosis.