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Division Spotlight
Education, Training & Workforce Development
The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
Meeting Spotlight
2021 Student Conference
April 8–10, 2021
Virtual Meeting
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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Latest News
Climate change needs an Operation Warp Speed
The government of the United States should throw its muscle behind ramping up a mammoth, rapid rollout of all forms of renewable energy through Operation Warp Speed, similar to what is being done with COVID-19, Clive Thompson writes in an Ideas column for Wired.
The rollout should include energy sources that we already know how to build—like solar and wind — but also experimental emerging sources such as geothermal and small nuclear, and cutting-edge forms of energy storage or transmission.
Thomas M. Sutton
Nuclear Science and Engineering | Volume 185 | Number 1 | January 2017 | Pages 174-183
Technical Paper | dx.doi.org/10.13182/NSE15-131
Articles are hosted by Taylor and Francis Online.
In the study of Monte Carlo statistical uncertainties for iterated-fission-source calculations, an important distinction is made between the real and the apparent variances. The former is the actual variance of a Monte Carlo calculation result, while the latter is an estimate of the former obtained using the results of the fission generations in the formula for uncorrelated random variates. For years it has been known that the apparent variance is a biased estimate of the real variance, and the reason for the bias has been understood. More recently, several authors have noted various interesting phenomena regarding the apparent and the real variances and the relationships among them. Some of these are an increase in the apparent variance near surfaces with reflecting boundary conditions, a nonuniform spatial distribution of the ratio of the apparent-to-real variance, the dependence of this ratio on the size of the region over which the result is tallied, and a rate of convergence of the real variance that is less than the inverse of the number of neutron histories run. This paper discusses a theoretical description of the Monte Carlo process using a discretized phase-space and then uses it to explain the causes of these phenomena.
