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Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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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.”
Taro Ueki
Nuclear Science and Engineering | Volume 160 | Number 2 | October 2008 | Pages 242-252
Technical Paper | doi.org/10.13182/NSE160-242
Articles are hosted by Taylor and Francis Online.
The stationarity diagnostics of source distribution in the iterated-source Monte Carlo computation for nuclear criticality and static nuclear reactor analysis have been studied using relative entropy and the Wilcoxon signed rank sum. Novel aspects of the diagnostics are (a) the relative entropy of permuted and nonpermuted source distributions and (b) a series of differenced relative entropies. Item (a) combined with averaging over random permutations has some smoothing effect on the fluctuation through iteration cycles. The benefit of item (b) is twofold: The differencing works as decorrelation, and the mean in stationarity of a differenced series is exactly zero. Therefore, the Wilcoxon signed rank sum has been applied to check the stationarity of the differenced relative entropy series. Another novel aspect of the diagnostics is the use of a problem-independent number of iteration cycles preceding the current iteration cycle upon the computation of the Wilcoxon signed rank sum. In addition, it has been shown that the progressive relative entropy in previous work can be used and the moving average of the Wilcoxon signed rank sums of its differenced series is a stringent measure of stationarity. Numerical results are presented for two- and three-dimensional modeling of an initial core of pressurized water reactors.