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Nuclear Criticality Safety
NCSD provides communication among nuclear criticality safety professionals through the development of standards, the evolution of training methods and materials, the presentation of technical data and procedures, and the creation of specialty publications. In these ways, the division furthers the exchange of technical information on nuclear criticality safety with the ultimate goal of promoting the safe handling of fissionable materials outside reactors.
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Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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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
Westinghouse’s lunar microreactor concept gets a contract for continued R&D
Westinghouse Electric Company announced last week that NASA and the Department of Energy have awarded the company a contract to continue developing a lunar microreactor concept for the Fission Surface Power (FSP) project.
Scott D. Ramsey, Roy A. Axford
Nuclear Science and Engineering | Volume 166 | Number 1 | September 2010 | Pages 48-57
Technical Paper | doi.org/10.13182/NSE09-64
Articles are hosted by Taylor and Francis Online.
We implement direct and approximate local sensitivity analysis techniques within the context of stochastic point kinetics neglecting delayed neutrons and external neutron sources. After reviewing the derivation of certain probabilities that the neutron population in a nuclear assembly is exactly zero [probabilities of extinction (POEs)], we consider their dependence on physical data. We subsequently focus on fission number distribution dependence and draw comparisons between two different data sets. As various POEs are dependent upon these data through the solution of a nonlinear ordinary differential equation, local sensitivity analysis provides a useful means through which to assess the effects of data reevaluation. We first conduct this analysis generally (though approximately) using Gâteaux-derivative methodology. Following the generalized developments, exact and approximate results for 235U are presented with a discussion concerning important consequences related to criticality safety.