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DOE launches UPRISE to boost nuclear capacity
The Department of Energy’s Office of Nuclear Energy has launched a new initiative to meet the government’s goal of increasing U.S. nuclear energy capacity by boosting the power output of existing nuclear reactors through uprates and restarts and by completing stalled reactor projects.
UPRISE, the Utility Power Reactor Incremental Scaling Effort, managed by Idaho National Laboratory, is to “deliver immediate results that will accelerate nuclear power growth and foster innovation to address the nation’s urgent energy needs,” DOE-NE said in its announcement.
R. N. Hwang
Nuclear Science and Engineering | Volume 167 | Number 1 | January 2011 | Pages 1-39
Technical Paper | doi.org/10.13182/NSE10-004
Articles are hosted by Taylor and Francis Online.
The fundamental basis regarding treatment of unresolved resonances and the construction of probability tables and the relevant issues with their application to reactor physics is critically examined. A theoretical model using integral transform techniques is developed that provides a viable alternative to the stochastic-based “ladder” method widely used to construct probability tables. A brief review of the statistical theory for treating the unresolved resonances is presented, followed by a critical examination of these methods. Then a reference method for computing various probability distributions at 0 K is derived analytically for Breit-Wigner resonances. This reference model provides the analytical insight and conceptual basis for extension to the general case of arbitrary temperature. The generalization to arbitrary temperature is accomplished using the Chebyshev expansion while maintaining the general forms of the distributions. Results of extensive benchmark calculations to verify the viability of the proposed method are presented. Finally, there is discussion of the remaining challenges in application of this new analytical approach, in particular, the issue of its extension beyond the Breit-Wigner approximation.