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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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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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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Glass strategy: Hanford’s enhanced waste glass program
The mission of the Department of Energy’s Office of River Protection (ORP) is to complete the safe cleanup of waste resulting from decades of nuclear weapons development. One of the most technologically challenging responsibilities is the safe disposition of approximately 56 million gallons of radioactive waste historically stored in 177 tanks at the Hanford Site in Washington state.
ORP has a clear incentive to reduce the overall mission duration and cost. One pathway is to develop and deploy innovative technical solutions that can advance baseline flow sheets toward higher efficiency operations while reducing identified risks without compromising safety. Vitrification is the baseline process that will convert both high-level and low-level radioactive waste at Hanford into a stable glass waste form for long-term storage and disposal.
Although vitrification is a mature technology, there are key areas where technology can further reduce operational risks, advance baseline processes to maximize waste throughput, and provide the underpinning to enhance operational flexibility; all steps in reducing mission duration and cost.
M. Assawaroongruengchot, G. Marleau
Nuclear Science and Engineering | Volume 155 | Number 1 | January 2007 | Pages 37-52
Technical Paper | doi.org/10.13182/NSE07-A2643
Articles are hosted by Taylor and Francis Online.
Most perturbation theory calculation methods for neutron transport problems are based on the assumption that the solution to the adjoint transport problem is known. Here we develop an adjoint transport solution based on the method of cyclic characteristics (MOCC) for two-dimensional fuel assembly problems with isotropic scattering. The main advantages of the MOCC method are (a) it requires lower computing time and memory spaces than the collision probability (CP) method and (b) it does not require the boundary surface currents as for the method of characteristics with isotropic tracking. In the MOCC the adjoint characteristics equations associated with a cyclic tracking line are formulated in such a way that a closed form for the adjoint angular function can be obtained. The mathematical relationship between the adjoint function obtained by CP method and the adjoint function by MOCC is also presented. In order to speed up the MOCC solution algorithm, group-reduction and group-splitting techniques based on the structure of the adjoint scattering matrix are implemented. In addition, a combined forward flux/adjoint function iteration scheme, based on the group-splitting technique and the common use of large numbers of variables storing tracking-line data and exponential values, is proposed to reduce the computing time. To demonstrate the efficiency of these algorithms, calculations are performed on a 17 × 17 pressurized water reactor lattice, a 37-pin CANDU [Canada deuterium uranium reactor] cell, and the Watanabe-Maynard benchmark. Comparisons of adjoint function and keff results obtained by the MOCC and the CP method are presented.