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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.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Taro Ueki
Nuclear Science and Engineering | Volume 178 | Number 1 | September 2014 | Pages 16-28
Technical Paper | doi.org/10.13182/NSE13-36
Articles are hosted by Taylor and Francis Online.
Fluctuation modeling of the macroscopic cross section is studied in the framework of a continuously distributed stochastic medium. In particular, spatial correlation is approached by fractional Brownian motion (FBM) and randomized Weierstrass function (RWF). Here, FBM is capable of modeling correlation due to coordinate increments while RWF has the same property as FBM on a small scale, is able to confine the influence of correlation within a certain range of increments, and is globally under a fixed variance. In numerical experiments, first flights of neutral particles are examined using Woodcock tracking. Results obtained indicate that the attenuation of an uncollided beam becomes slower than the exponential law of the corresponding nonstochastic homogeneous medium as the spatial correlation changes from negative to positive; this departure to the slower side is very small or negligible in the full antipersistency limit of negative correlation. It is also shown that the departure from the exponential law of attenuation is nearly negligible if the influence of correlation is confined within the mean free path (mfp) determined by the macroscopic cross section of the corresponding nonstochastic homogeneous medium. However, the mfp's for individual realizations of the medium distribute widely. FBM turns out not to be feasible for modeling positive correlation. Overall, RWF virtually eliminates the risk of negative values of the macroscopic cross section inherent in the FBM modeling.