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The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
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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.
M. Natelson
Nuclear Science and Engineering | Volume 43 | Number 2 | February 1971 | Pages 131-144
Technical Paper | doi.org/10.13182/NSE71-A21261
Articles are hosted by Taylor and Francis Online.
The derivation of discrete ordinate and discrete ordinate-like approximations from variational principles for the one-speed transport equation is explored here. Standard discrete ordinate approximations are derived from a first-order stationary variational principle. The derivation yields a prescription for ordinates to be used given a selection of weights. Resultant quadrature schemes are compared numerically with those in common use. These new schemes derived using the weights of SN quadratures do not show significant variations in performance from the parent SN schemes. In the second portion of the paper, a new “modified” discrete ordinate approximation, MDN, is found by applying the same techniques as in the derivation of the standard approximation, this time, however, using an extremum second-order variational principle. The new approximation is compared through several numerical examples with standard discrete ordinate, simplified PN, and standard PN approximations. The MDN results do show a mitigation of the ray effects associated with standard discrete ordinate calculations (DN), but for gross region-wise absorption rates its accuracy for low orders is more like that of simplified PN rather than of PN or DN approximations. It is concluded that a low-order MDN approximation should not be a candidate to replace diffusion theory. The approximation may, however, have some application as a calculational standard.