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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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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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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.
Taewan Noh, Warren F. Miller, Jr., Jim E. Morel
Nuclear Science and Engineering | Volume 123 | Number 1 | May 1996 | Pages 38-56
Technical Paper | doi.org/10.13182/NSE96-A24211
Articles are hosted by Taylor and Francis Online.
The finite element and lumped finite element methods for the spatial differencing of the even-parity discrete ordinates neutron transport equations (EPSN) in two-dimensional x-y geometry are applied. In addition, the simplified even-parity discrete ordinates equations (SEPSN) as an approximation to the EPSN transport equations are developed. The SEPSN equations are more efficient to solve than the EPSN equations due to a reduction in angular domain of one-half, the applicability of a simple five-point diffusion operator, and directionally uncoupled reflective boundary conditions. Furthermore, the SEPSN equations satisfy the same diffusion limits as EPSN in an optically thick regime, appear to have no ray effect, and converge faster than EPSN when using a diffusion synthetic acceleration (DSA). Also, unlike the case of EPSN, the SEPSN solutions are strictly positive, thus requiring no negative flux fixups. It is also demonstrated that SEPSN is a generalization of the simplified PN method. Most importantly, in these second-order approaches, an unconditionally effective DSA scheme can be achieved by simply integrating the differenced EPSN and SEPSN equations over the angles. It is difficult to obtain a consistent DSA scheme with the first-order SN equations. This is because a second-order DSA equation must generally be derived directly from the differenced first-order SN equations.