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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.”
Massimiliano Rosa, James S. Warsa, Jae H. Chang
Nuclear Science and Engineering | Volume 164 | Number 3 | March 2010 | Pages 248-263
Technical Paper | doi.org/10.13182/NSE09-26
Articles are hosted by Taylor and Francis Online.
A Fourier analysis is conducted for the discrete ordinates, or SN, approximation of the neutron transport problem solved with Richardson iteration (source iteration) and Richardson iteration preconditioned with transport synthetic acceleration (TSA), using the inexact parallel block-Jacobi (IPBJ) algorithm both in slab and two-dimensional Cartesian geometry. Both traditional, or “beta,” TSA (TTSA) and a modified TSA (MTSA), in which only the scattering in the low-order equations is reduced by some nonnegative factor < 1, are considered.The results for the unaccelerated algorithm show that convergence of IPBJ can degrade, leading in particular to stagnation of the generalized minimum residual method with restart parameter m, GMRES(m), in problems containing optically thin subdomains. The IPBJ algorithm preconditioned with TTSA can be effective, provided the parameter is properly tuned for a given scattering ratio c, but is potentially unstable. Compared to TTSA, MTSA is less sensitive to the choice of , more effective for the same computational effort, measured in terms of the effective scattering ratio c′, and it is unconditionally stable.
