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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.
W. W. Marr, M. M. El-Wakil
Nuclear Science and Engineering | Volume 41 | Number 2 | August 1970 | Pages 271-280
Technical Paper | doi.org/10.13182/NSE70-A20713
Articles are hosted by Taylor and Francis Online.
A serial (discrete-time continuous-space) method is employed to solve the unsteady-state energy equations in porous systems on a hybrid computer. The nonlinear, coupled partial-differential equations are solved by replacing the time derivatives with backward finite-difference approximations. To increase the order of accuracy in the time increment of the solution, the Crank-Nicholson scheme is used. The resulting difference-differential equations are solved in the direction opposite to that of the fluid flow to eliminate computational instability. The average temperatures over the consecutive time steps are solved on the analog portion of the hybrid computer. Solutions of the present time step are obtained by combining the analog solutions with those of the previous time step stored in the digital computer. The commonly encountered, mixed boundary conditions are satisfied by using a steepest descent iteration scheme based on least-squares-error minimization. A so-called binary-search technique provides reasonable initial trial values from which the iteration process converges. The trial values are improved by making use of the parameter influence coefficients that are obtained by taking finite differences through a number of test runs at the beginning of the solution and are taken to be constant during the entire solution time. In most cases, the iteration process converges in two to three iterations per boundary value searched. Comparisons of the hybrid computer solutions agree with those obtained by other numerical methods on a digital computer within 1%.