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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.”
Hyun Chul Lee, Hyung Jin Shim, Chang Hyo Kim
Nuclear Technology | Volume 135 | Number 1 | July 2001 | Pages 39-50
Technical Paper | Fuel Cycle and Management | doi.org/10.13182/NT01-A3204
Articles are hosted by Taylor and Francis Online.
An adaptive control scheme of simulated annealing (SA) parameters derived from the polynomial-time cooling schedule is presented in terms of the efficiency enhancement of the SA algorithm. The parallel computing adaptive SA optimization scheme, which incorporates the optimization-layer-by-layer (OLL) neutronics evaluation model is then applied to determining the optimum fuel assembly (FA) loading pattern (LP) in the Korea Nuclear Unit 2 pressurized water reactor (PWR) using seven Pentium personal computers (three 266-MHz Pentium II and four 200-MHz Pentium Pro computers). It is shown that the parallel scheme enhances the efficiency of the SA optimization computation significantly but that it can get trapped in local optimum LPs more frequently than the single-processor SA scheme unless one takes preventive steps. As a way to prevent trapping of the parallel scheme in local optima, using multiple seed LPs is proposed instead of a single LP with which the individual processors start each stage, and how to determine the multiple seed LPs is discussed. Because of the high efficiency of the parallel scheme, the acceptability of a hybrid neutronics evaluation model, which is slower but more accurate than the OLL model, in the parallel optimization calculation is examined from the standpoint of computing time. By demonstrating that the FA LP optimization calculation for the equilibrium cycle core of the KNU-2 PWR can be completed in <1 h on seven Pentiums, we justify the routine utilization of the hybrid model in the parallel SA optimization scheme.