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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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Deep Space: The new frontier of radiation controls
In commercial nuclear power, there has always been a deliberate tension between the regulator and the utility owner. The regulator fundamentally exists to protect the worker, and the utility, to make a profit. It is a win-win balance.
From the U.S. nuclear industry has emerged a brilliantly successful occupational nuclear safety record—largely the result of an ALARA (as low as reasonably achievable) process that has driven exposure rates down to what only a decade ago would have been considered unthinkable. In the U.S. nuclear industry, the system has accomplished an excellent, nearly seamless process that succeeds to the benefit of both employee and utility owner.
Sergey S. Gorodkov
Nuclear Science and Engineering | Volume 172 | Number 2 | October 2012 | Pages 193-201
Technical Paper | doi.org/10.13182/NSE11-105
Articles are hosted by Taylor and Francis Online.
Significant underprediction bias in uncertainties of neutron flux is observed in Monte Carlo criticality calculations of large cores. It is universally recognized that this underprediction is closely associated with the ratio of the second-largest eigenvalue to the largest eigenvalue, or the dominance ratio, of the fission kernel. In this paper a close analogy is presumed between neutron flux autocorrelations in Monte Carlo calculations and flux variances due to stochastic uncertainties of the properties of fuel assemblies within the manufacturing tolerance limits. Interesting consequences following from this analogy are confirmed in quite realistic calculations. A useful expression is derived for fast evaluation of the minimal number of histories to be modeled to achieve preset confidence limits of flux distribution in large cores.