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Conference Spotlight
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.
Edward W. Larsen
Nuclear Science and Engineering | Volume 83 | Number 1 | January 1983 | Pages 90-99
Technical Paper | doi.org/10.13182/NSE83-A17992
Articles are hosted by Taylor and Francis Online.
A parameter ∊ is introduced into the discrete ordinates equations in such a way that as ∊ tends to zero, the solution of these equations tends to the solution of the standard diffusion equation. The behavior of spatial differencing schemes for the discrete ordinates equations is then studied, for fixed spatial and angular meshes, in the limit as ∊ tends to zero. We show that numerical solutions obtained by the diamond difference, linear characteristic, linear discontinuous, linear moments, exponential, and Alcouffe schemes all converge, in this limit, to the correct transport or diffusion result, while numerical solutions obtained by the weighted-diamond and Takeuchi schemes do not converge to the correct limiting result.