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Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Division Spotlight
Aerospace Nuclear Science & Technology
Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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
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.
Miguel Ceceñas-Falcón, Robert M. Edwards
Nuclear Technology | Volume 143 | Number 2 | August 2003 | Pages 125-131
Technical Paper | Nuclear Plant Instrumentation, Control, and Human-Machine Interface Technologies | doi.org/10.13182/NT03-A3402
Articles are hosted by Taylor and Francis Online.
The study of the first harmonic mode of the neutron spectrum in a boiling water reactor (BWR) yields the capability to assess the decay ratio for the harmonic mode and anticipate the impact on the fundamental mode when an out-of-phase oscillation is about to take place. In this work, the neutron spectrum for a BWR is approximated as a linear combination of the fundamental and first harmonic modes, and these two modes are studied applying reduced order modal models. A stability estimator is constructed to monitor the development of the harmonic mode instability through the calculation of the decay ratio. To achieve an estimation of the decay ratio for each mode, the estimator requires the separation of both modes from the neutron spectrum, and a method to obtain these modes based on a bare homogeneous reactor is presented. The Reduced Order Modal Estimator is tested with computer-generated data and with data from the Ringhals Stability Benchmark.
