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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.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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General Kenneth Nichols and the Manhattan Project
Nichols
The Oak Ridger has published the latest in a series of articles about General Kenneth D. Nichols, the Manhattan Project, and the 1954 Atomic Energy Act. The series has been produced by Nichols’ grandniece Barbara Rogers Scollin and Oak Ridge (Tenn.) city historian David Ray Smith. Gen. Nichols (1907–2000) was the district engineer for the Manhattan Engineer District during the Manhattan Project.
As Smith and Scollin explain, Nichols “had supervision of the research and development connected with, and the design, construction, and operation of, all plants required to produce plutonium-239 and uranium-235, including the construction of the towns of Oak Ridge, Tennessee, and Richland, Washington. The responsibility of his position was massive as he oversaw a workforce of both military and civilian personnel of approximately 125,000; his Oak Ridge office became the center of the wartime atomic energy’s activities.”
Tunc Aldemir, Steven A. Arndt, Don. W. Miller
Nuclear Technology | Volume 76 | Number 2 | February 1987 | Pages 248-259
Technical Paper | Technique | doi.org/10.13182/NT87-A33879
Articles are hosted by Taylor and Francis Online.
Ionization chambers (ICs) are used in reactor protection instrument channels for monitoring neutron flux levels. These neutron sensors may degrade during the operation of the reactor through a change in their fill-gas characteristics. The comparison of the simulated and measured transient IC response to bias voltage perturbations can lead to the identification of these mechanisms. Once the mechanisms are identified, their impact on instrument channel response can be assessed by parametric studies. The charge transport model for such an identification and assessment process consists of three coupled nonlinear parabolic differential equations. The initial conditions for these equations are found by solving for the steady-state charge distribution in the IC fill gas prior to bias voltage perturbation. The space-time charge distribution in the IC is determined by a fully explicit-semi-implicit numerical scheme. The model is implemented to determine the transient response of a N2- and a xenon-filled IC to a 500- V bias voltage perturbation. In this implementation, good agreement is observed between the predicted and measured responses, with substantial improvement over the previously proposed models. The comparison of the numerical scheme to the interactive continuous system modeling program technique used in the previous studies indicates a twentyfold reduction in the number of time steps required for the simulation of a 5-ms transient. The model is also capable of quantifying the effect of fill-gas impurities on the transient IC response.