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Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
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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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General Kenneth Nichols and the Manhattan Project
Nichols
The Oak Ridger has published the latest in a series of articles about General Kenneth D. Nichols, the Manhattan Project, and the 1954 Atomic Energy Act. The series has been produced by Nichols’ grandniece Barbara Rogers Scollin and Oak Ridge (Tenn.) city historian David Ray Smith. Gen. Nichols (1907–2000) was the district engineer for the Manhattan Engineer District during the Manhattan Project.
As Smith and Scollin explain, Nichols “had supervision of the research and development connected with, and the design, construction, and operation of, all plants required to produce plutonium-239 and uranium-235, including the construction of the towns of Oak Ridge, Tennessee, and Richland, Washington. The responsibility of his position was massive as he oversaw a workforce of both military and civilian personnel of approximately 125,000; his Oak Ridge office became the center of the wartime atomic energy’s activities.”
Ser Gi Hong, Kang-Seog Kim, Jae Seung Song
Nuclear Science and Engineering | Volume 164 | Number 1 | January 2010 | Pages 33-52
Technical Paper | doi.org/10.13182/NSE09-18
Articles are hosted by Taylor and Francis Online.
This paper analyzes the convergence of the rebalance iteration methods for accelerating the power iteration method of the discrete ordinates transport equation in the eigenvalue problem. The rebalance iteration methods include the coarse mesh rebalance (CMR), the coarse mesh finite difference (CMFD), and the partial current-based CMFD methods. The convergence analysis is performed with the well-known Fourier analysis through linearization. In the linearized form, these rebalance methods are formulated in a unified way where the rebalance methods are different only in a parameter. The analyses are applied for both one- and two-group problems in a homogeneous infinite medium and a finite medium having periodic boundary conditions. The theoretical analysis shows that the convergences of the rebalance methods for the eigenvalue problems are closely related with the ones for the fixed source problems and that the convergences for the eigenvalue problems can be analyzed with the formula for the fixed source problem after transforming the scattering cross sections into a different cross-section set. The numerical tests show that the Fourier convergence analysis provides a reasonable estimate for the numerical spectral radii for the model problems.
