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Robotics & Remote Systems
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.
B. R. Wienke, R. E. Hiromoto
Nuclear Science and Engineering | Volume 90 | Number 1 | May 1985 | Pages 116-123
Technical Note | doi.org/10.13182/NSE85-1
Articles are hosted by Taylor and Francis Online.
The iterative, multigroup, discrete ordinates Sn representation for the linear transport equation enjoys widespread computational use and popularity. Serial iteration schemes and numerical algorithms developed over the years provide a timely framework for parallel extension. On the Denelcor heterogeneous element processor, three parallel iteration schemes (two chaotic, one ordered) are investigated for solving the one-dimensional Sn transport equation. Concurrent inner sweeps, coupled acceleration techniques, synchronized inner-outer loops, and chaotic iteration are described and results of computations are contrasted. The multigroup representation and serial iteration methods are also reviewed. The basic iterative Sn approach lends itself to parallel tasking, portably affording an effective medium for performing transport calculations on future architectures. This analysis represents a first attempt to extend serial Sn algorithms to parallel environments and provides good baseline estimates on ease of parallel implementation, relative algorithm efficiency, comparative speedup, and some future directions. An ordered and chaotic strategy is examined, with and without concurrent rebalance and diffusion acceleration, which efficiently support high degrees of parallelization and appear to be robust and viable parallel iteration techniques. The standard inner-outer technique, presently employed in a majority of production Sn codes, is a weaker parallel iteration strategy. Modifications, extensions, and recoding effort to parallelize existing serial algorithms are also simple. Chaotic iteration, heretofore difficult to simulate on serial machines, holds promise and appears to converge faster than ordered schemes. Actual parallel speedup and efficiency are high and payoff appears substantial.