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Division Spotlight
Human Factors, Instrumentation & Controls
Improving task performance, system reliability, system and personnel safety, efficiency, and effectiveness are the division's main objectives. Its major areas of interest include task design, procedures, training, instrument and control layout and placement, stress control, anthropometrics, psychological input, and motivation.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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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Latest News
TerraPower begins U.K. regulatory approval process
Seattle-based TerraPower signaled its interest this week in building its Natrium small modular reactor in the United Kingdom, the company announced.
TerraPower sent a letter to the U.K.’s Department for Energy Security and Net Zero, formally establishing its intention to enter the U.K. generic design assessment (GDA) process. This is TerraPower’s first step in deployment of its Natrium technology—a 345-MW sodium fast reactor coupled with a molten salt energy storage unit—on the international stage.
Fahir Borak
Nuclear Technology | Volume 13 | Number 1 | January 1972 | Pages 20-28
Technical Paper | Reactor | doi.org/10.13182/NT72-A31063
Articles are hosted by Taylor and Francis Online.
Using one-group diffusion theory, linear extrapolation distances for centrally and eccentrically located black control rods in cylindrical geometries have been determined by the pulsed neutron method. It is found that for a given radius control rod, the extrapolation distance increases with increasing moderator radius. Linear extrapolation distance is also found to increase with eccentrical location of control rods. In general, the values of the extrapolation distances determined for central rods in diffusion theory, in the range of moderator radii studied, are higher in value by 10 to 100% than the classical values based on the theoretical calculations of Davison and Zaretsky. The values of the linear extrapolation distances for eccentric control rods, in the range of the moderator radii studied, are also higher than the central control rod extrapolation distances up to a factor of 6, the increase depending on the location of the control rods.
