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Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.”
Edward W. Larsen
Nuclear Science and Engineering | Volume 83 | Number 1 | January 1983 | Pages 90-99
Technical Paper | doi.org/10.13182/NSE83-A17992
Articles are hosted by Taylor and Francis Online.
A parameter ∊ is introduced into the discrete ordinates equations in such a way that as ∊ tends to zero, the solution of these equations tends to the solution of the standard diffusion equation. The behavior of spatial differencing schemes for the discrete ordinates equations is then studied, for fixed spatial and angular meshes, in the limit as ∊ tends to zero. We show that numerical solutions obtained by the diamond difference, linear characteristic, linear discontinuous, linear moments, exponential, and Alcouffe schemes all converge, in this limit, to the correct transport or diffusion result, while numerical solutions obtained by the weighted-diamond and Takeuchi schemes do not converge to the correct limiting result.