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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.
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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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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.
Stefan Taczanowski
Fusion Science and Technology | Volume 13 | Number 1 | January 1988 | Pages 125-130
Technical Paper | Blanket Engineering | doi.org/10.13182/FST88-A25089
Articles are hosted by Taylor and Francis Online.
The resonance self-shielding effects in heterogeneous fissile breeding systems have been investigated. In media having peaked resonance cross sections, the influence of heterogeneities is manifested in the energy and space neutron flux depressions. The outcomes of numerical calculations performed for various pellet sizes and fissile material concentrations are shown in the form of “het-to-hom” ratios of the results obtained by considering normalized heterogeneities in relation to those accounting for self-shielding in respective, computationally homogenized mixtures. The observed reduction in fissile breeding and the increase in tritium breeding, 233U fissions, and parasitic absorptions are of the order of several tens of percent, depending on the fertile content. It is emphasized that neglecting heterogeneities leads to serious errors and nonoptimum designs, thus proving to be inadmissible in neutronic calculations for emerging nuclear energy systems.
