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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.”
B. R. Upadhyaya, M. Kitamura
Nuclear Science and Engineering | Volume 77 | Number 4 | April 1981 | Pages 480-492
Technical Paper | doi.org/10.13182/NSE81-A18961
Articles are hosted by Taylor and Francis Online.
A method of monitoring stability of boiling water reactors (BWRs) has been developed. The stability parameters were derived from empirical discrete-time modeling of process noise signals and neutron noise signals. Data were taken from an operating BWR-4, and used to perform univariate analysis of average power range monitor (APRM), and local power range monitor signals, and multivariate analysis of APRM and the process signals, reactor pressure, and core flow rate. The parameters such as decay ratio, damping ratio, and characteristic frequency of oscillation, which represent the system stability, were estimated from the impulse response of the system. The impulse response was determined by using the time series models and contains information about the closed loop dynamics of a BWR. The results indicate the feasibility of using APRM noise analysis for monitoring overall core stability and temporal variations in the stability margin of the reactor. Any significant variation in the stability parameters can be studied using multivariate noise signal algorithms, and cause and effect relationships can be obtained. Because the derived parameters depend on the random noise properties of the signals, this nonperturbing method is most useful for monitoring changes in stability. If an absolute measurement is necessary, a perturbation test must be performed.