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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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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.”
Isao Murata, Detlef Filges, Frank Goldenbaum
Nuclear Science and Engineering | Volume 159 | Number 3 | July 2008 | Pages 273-283
Technical Paper | doi.org/10.13182/NSE159-273
Articles are hosted by Taylor and Francis Online.
A new importance estimation method, which is based on the adjoint function definition, has been proposed especially for the weight window (WW) technique of MCNP, which is well known as one of the most powerful variance-reduction techniques in Monte Carlo codes. The method employs the scattering point base importance estimation, unlike the WW generator (WWG) of MCNP for the point detector function. Every scattering point has an adjoint contribution to the detector, with which a space-, energy-, and angle-dependent importance for WW could be estimated. From the numerical test calculations, the basic performance was confirmed to be better than WWG by comparing figure-of-merit values. It would be expected that the performance of WWG would be well improved by using the present method instead of the current MCNP routine of accumulating the detector contribution for the F5 tally. The presently proposed method would be a strong tool to estimate the importance applicable to various variance-reduction techniques in Monte Carlo codes.
