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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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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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WIPP’s SSCVS: A breath of fresh air
This spring, the Department of Energy’s Office of Environmental Management announced that it had achieved a major milestone by completing commissioning of the Safety Significant Confinement Ventilation System (SSCVS) facility—a new, state-of-the-art, large-scale ventilation system at the Waste Isolation Pilot Plant, the DOE’s geologic repository for defense-related transuranic (TRU) waste in New Mexico.
Weston M. Stacey, Jr.
Nuclear Science and Engineering | Volume 40 | Number 1 | April 1970 | Pages 73-90
Technical Paper | doi.org/10.13182/NSE70-A18880
Articles are hosted by Taylor and Francis Online.
The multigroup neutron kinetics equations are derived and investigated for the case when the within-group weighting spectra, which are used in defining group constants, are space- and time-dependent. New terms are introduced by the space- and time-dependence of these weighting spectra. The derivation is carried through the hierarchy of operations by which the continuous space, time, and lethargy dependence is replaced by a discrete representation. The new terms do not alter the usual positivity properties associated with the discrete multigroup kinetics equations, provided that certain conditions are satisfied. Conditions are also established which are sufficient to ensure that the discrete representation is adjoint consistent; i.e., the discrete representation of the adjoint equation is mathematically adjoint to the discrete representation of the direct equation. A similar development is presented for the Spectral Synthesis approximation. Conditions are established for the adjoint consistency of the discrete representation. The type of positivity argument made for the multigroup equations is shown to be invalid for the Spectral Synthesis equations.
