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Division Spotlight
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.
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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Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
Masaharu Kitamura, Kunihiko Matsubara, Ritsuo Oguma
Nuclear Science and Engineering | Volume 70 | Number 1 | April 1979 | Pages 106-110
Technical Note | doi.org/10.13182/NSE79-A18934
Articles are hosted by Taylor and Francis Online.
The feasibility of reactor noise analysis by autoregressive (AR) modeling is studied from the viewpoint of system identifiability. A condition is derived in which only a part of the identified model becomes meaningful. A practical checking method termed “RRV checking” is proposed, with which the occurrence of the condition is recognized a posteriori for the estimated AR model. This method is applied to AR models obtained by processing the experimental data from the Japan Power Demonstration Reactor II. These models would have been discarded from a conventional viewpoint, since some parts of the model showed physically implausible characteristics. It is verified that the RR V checking method and the empirical evaluation of the usability of the model resulted in the same conclusion about the acceptability of the parts of the models. The processes evaluated to be identifiable from the reactor noise are the response of the fuel temperature to the neutron density and the response of the steam control valve to the reactor pressure. The present method is particularly useful if a priori knowledge about the dynamics of the objective process is limited before the identification experiment.