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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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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
G. I. Bell, G. E. Hansen, and H. A. Sandmeier
Nuclear Science and Engineering | Volume 28 | Number 3 | June 1967 | Pages 376-383
Technical Paper | doi.org/10.13182/NSE67-2
Articles are hosted by Taylor and Francis Online.
Much theoretical work has been done in the past to represent the angular dependence in the scattering source term of the Boltzmann equation by means of Legendre or other series expansions. However, relatively little work has been done to feed this information into our present-day SN codes. The SN transport codes at LASL allow a representation of anisotropy in the scattering source term by means of multi-table cross-section sets and two formalisms are given here to generate these sets. Both involve the expansion of scattering cross sections in a series of Legendre polynomials, and incorporation of the expansion coefficients in the tables of transfer cross sections. One, called a consistent P approximation, involves a simple truncation of the series; while the other, called an extended transport approximation, includes an attempt to approximate the next higher term in the series. A general expression is derived for the error in the neutron flux due to either approximation. The numerical evaluation of SN cross-section entries for these formalisms has been computerized. Convergence with respect to Number of Tables is numerically investigated for several different neutron-transport problems: a) deep penetration of high-energy neutrons in air; b) critical size of an enriched-uranium bare sphere; c) reflector savings for an enriched-uranium sphere immersed in H2O; and d) fast-reactor core mockup on ANL's ZPR-III. It is concluded from these problems that both approximations converge rapidly with increasing number of tables and that the simple transport approximation gives quite accurate results for a wide range of problems.