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ANS Student Conference 2025
April 3–5, 2025
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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.”
S. Nakamura
Nuclear Science and Engineering | Volume 61 | Number 1 | September 1976 | Pages 98-106
Technical Paper | doi.org/10.13182/NSE76-A28465
Articles are hosted by Taylor and Francis Online.
The accelerating effect of coarse-mesh rebalancing on the low-order Chebyshev polynomial iterations to obtain the fundamental eigenvector of large homogeneous linear systems associated with elliptic partial-differential equations is mathematically analyzed. Coarse-mesh rebalancing is shown to have a positive accelerating effect if one of the following conditions is met: (a) the weighting vectors are not contaminated with high eigenvector components, (b) Galerkin's weighting vectors are used, or (c) the non-Galerkin weighting vectors are similar to the trial vectors. As another interesting result, it is shown that the overshooting effect is related to the fourth and higher eigenvector components that have spatially odd parities. If the above condition, (c), is met, there is no overshooting; otherwise, the acceleration effect with non-Galerkin weighting vectors is unpredictable.