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2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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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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Seconds Matter: Rethinking Nuclear Facility Security for the Modern Threat Landscape
In today’s rapidly evolving threat environment, nuclear facilities must prioritize speed and precision in their security responses—because in critical moments, every second counts. An early warning system serves as a vital layer of defense, enabling real-time detection of potential intrusions or anomalies before they escalate into full-blown incidents. By providing immediate alerts and actionable intelligence, these systems empower security personnel to respond decisively, minimizing risk to infrastructure, personnel, and the public. The ability to anticipate and intercept threats at the earliest possible stage not only enhances operational resilience but also reinforces public trust in the safety of nuclear operations. Investing in such proactive technologies is no longer optional—it’s essential for modern nuclear security.
F. E. LeVert, M. A. Schultz
Nuclear Science and Engineering | Volume 49 | Number 2 | October 1972 | Pages 188-201
Technical Paper | doi.org/10.13182/NSE72-A35506
Articles are hosted by Taylor and Francis Online.
Local measurements of the inherent fluctuations in the gamma-ray density at specific locations in the core of the Pennsylvania State Triga Reactor have been conducted using two externally located detectors. Local power was determined for positions up to the center of the core from a distance of approximately 200 cm by measuring the zero-time cross correlation function in small intervals. Voids introduced by the removal of single fuel elements were readily located and mapped. Single collimator dc scans along diagonal rows in the core were successful in resolving the individual rows of fuel in the core. A comparison between the neutron distribution predicted by two dimensional multi-group diffusion theory and a single collimator measurement showed very good agreement in their respective shapes. Cospectral densities were obtained for the two cases where the collimators focused on and off a volume of fuel in the core. The frequency response data indicated, when interpreted in terms of an analytical model, that the observed output fluctuations were caused by temperature and coolant flow input fluctuations.