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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.
Meeting Spotlight
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.”
William E. Kastenberg
Nuclear Science and Engineering | Volume 37 | Number 1 | July 1969 | Pages 19-29
Technical Paper | doi.org/10.13182/NSE69-A20895
Articles are hosted by Taylor and Francis Online.
A general formalism for the determination of stability criteria by the method of comparison functions is derived for nuclear reactors whose system dynamics are governed by a coupled set of space-dependent nonlinear differential equations. The results obtained are applicable to the nonlinear multigroup diffusion equations with temperature feedback. A stability criterion for the nontrivial equilibrium state is presented in a theorem. In addition, two corollaries are presented for the particular cases of negative feedback. The criteria so obtained represent a measure of the “dissipative” forces as estimated by the eigenvalues of the linearized problem vs a measure of the “disruptive” forces caused by the feedback. If the net effect is dissipative then the system is asymptotically stable in the sense of Lyapunov. Two examples are presented to illustrate the formalism and use of the criteria. In the second example, a stability criteria for two-group theory with linear temperature feedback is derived directly from the equations of motion by this method.
