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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 Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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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Fusion Science and Technology
Latest News
Zap Energy hits 37-million-degree electron temperatures in compact fusion device
Zap Energy announced April 23 that it has reached 1-3 keV plasma electron temperatures—roughly the equivalent of 11 to 37 million degrees Celsius—using its sheared-flow-stabilized Z-pinch approach to fusion. Reaching temperatures above that of the sun’s core (which is 10 million degrees Celsius temperature) is just one hurdle required before any fusion confinement concept can realistically pursue net gain and fusion energy.
Dimitar Altiparmakov, Robert Wiersma
Nuclear Science and Engineering | Volume 182 | Number 4 | April 2016 | Pages 395-416
Technical Paper | doi.org/10.13182/NSE15-28
Articles are hosted by Taylor and Francis Online.
The size and the density of the collision probability matrix have been recognized as major deficiencies since the early era of development of the collision probability method. The computing time of the matrix inversion is proportional to the third degree of the number of unknowns per group and increases rapidly with the increase of the problem size. This is a severe limitation that restricts the capabilities of the method and makes it inapplicable to large-size neutron transport problems. This paper presents a new solution method that overcomes these deficiencies and extends the capabilities of the collision probability approximation. To reduce the matrix inversion time, a block partition is applied, and the solution is obtained by block iteration. Owing to the partition, the method is suitable for parallel calculations on contemporary computers. To illustrate the potential advantages, the following three groups of calculations are presented. In the first group, results of sequential calculations reveal the advantage over traditional methods of direct solution and point iteration. In the second group, memory shared parallelism results present the speedup that can be achieved in solving medium-size problems on a standard multicore desktop computer. In the third group, distributed memory calculations show an example of the solution of a large-size two-dimensional model problem of a heavy water power reactor invoking 100 thousand unknowns per group.