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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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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
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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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Latest News
Dragonfly, a Pu-fueled drone heading to Titan, gets key NASA approval
Curiosity landed on Mars sporting a radioisotope thermoelectric generator (RTG) in 2012, and a second NASA rover, Perseverance, landed in 2021. Both are still rolling across the red planet in the name of science. Another exploratory craft with a similar plutonium-238–fueled RTG but a very different mission—to fly between multiple test sites on Titan, Saturn’s largest moon—recently got one step closer to deployment.
On April 25, NASA and the Johns Hopkins University Applied Physics Laboratory (APL) announced that the Dragonfly mission to Saturn’s icy moon passed its critical design review. “Passing this mission milestone means that Dragonfly’s mission design, fabrication, integration, and test plans are all approved, and the mission can now turn its attention to the construction of the spacecraft itself,” according to NASA.
I. Maya, Hugh D. Campbell
Fusion Science and Technology | Volume 4 | Number 2 | September 1983 | Pages 135-140
Plasma Engineering | doi.org/10.13182/FST83-A22857
Articles are hosted by Taylor and Francis Online.
An analysis of the thermal balance of a fusioning plasma from a control system perspective has been performed. The requirements for stability and the response characteristics of the thermal balance have been evaluated. The results show that open-loop equilibria are characterized by restrictively narrow stable operating temperature regimes and generally poor system performance. Closed-loop proportional feedback using the fuel feedrate and injection energy can be used to extend the stable operating temperature regime and significantly improve the system response. Thus, high open-loop temperature overshoots without neutral beam injection can be reduced to acceptable levels at temperatures as low as 20 keV, with a decrease in the settling time to under 30 sec. With 75 keV injection energy, acceptable overshoot can be obtained at plasma temperatures as low as 10 keV, with the time-to-peak below 20 sec and settling times less than 30 sec. It is still difficult to simultaneously satisfy overshoot and speed of response requirements at low temperatures with low feedback fractions. Additional improvement is available using proportional-integral-derivative (PID) control.
