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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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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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Latest News
First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
Todd J. Urbatsch, R. Arthur Forster, Richard E. Prael, Richard J. Beckman
Nuclear Technology | Volume 111 | Number 2 | August 1995 | Pages 169-182
Technical Paper | Nuclear Criticality Safety Special / Fission Reactor | doi.org/10.13182/NT95-A35128
Articles are hosted by Taylor and Francis Online.
The Monte Carlo code MCNP has three different, but correlated, estimators for calculating keff in nuclear criticality calculations: collision, absorption, and track length estimators. The combination of these three estimators, the three-combined keff estimator, is shown to be the best keff estimator available in MCNP for estimating keff confidence intervals. Theoretically, the Gauss-Markov theorem provides a solid foundation for MCNP’s three-combined estimator. Analytically, a statistical study, where the estimates are drawn using a known covariance matrix, shows that the three-combined estimator is superior to the estimator with the smallest variance. Empirically, MCNP examples for several physical systems demonstrate the three-combined estimator’s superiority over each of the three individual estimators and its correct coverage rates. Additionally, the importance of MCNP’s statistical checks is demonstrated.