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The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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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.
Li Mao, J. P. Both, J. C. Nimal
Nuclear Science and Engineering | Volume 130 | Number 2 | October 1998 | Pages 226-238
Technical Paper | doi.org/10.13182/NSE98-A2002
Articles are hosted by Taylor and Francis Online.
The coefficients of a truncated Legendre series are usually used in multigroup cross-section sets to treat the angular distribution for a group-to-group scattering event. Fine energy meshes and low-order Legendre expansions result in negative values in the corresponding multigroup Legendre expansions; therefore, special transfer matrix treatments for multigroup cross sections are needed.The difficulties of the truncated Legendre series representation in treating multigroup transfer are explained. In TRIMARAN-II, two existing standard methods, the equally probable step function (EPSF) representation and the discrete angle representation, which are based on preservation (at least approximately) of the first moments, are studied. The discrete angle representation has the advantage of accurately preserving the moments, but it may cause ray effects; the EPSF representation can eliminate ray effects, but it is not suitable for the treatment of the transfer matrix for material mixtures, because both forward- and backward-peaked scattering are present in this kind of cross section. A new method, the nonequally probable step function (NEPSF) representation, which combines the advantages of both the discrete angle and EPSF representations, is introduced. It can eliminate ray effects and accurately preserve the moments. The conjugate gradient method, powerful for solving multidimensional minimization problems, is used to obtain both the EPSF and NEPSF representations. A problem of neutron transmission in a hydrogenous material is used to compare the three representations. Comparisons of the TRIMARAN-II results with the three representations to those of the TRIPOLI-4 pointwise cross-section Monte Carlo code are given.