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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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Latest News
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.
J. I. Duo, Y. Y. Azmy
Nuclear Science and Engineering | Volume 162 | Number 1 | May 2009 | Pages 41-55
Technical Paper | doi.org/10.13182/NSE08-28
Articles are hosted by Taylor and Francis Online.
This paper analyzes the spatial discretization of the discrete ordinates (DO) approximation of the transport equation. A new method, the singular characteristics tracking algorithm, is developed to account for potential nonsmoothness across the singular characteristics in the exact solution of the DO approximation to the transport equation. Numerical results in two-dimensional problems show improved rate of convergence of the exact solution of the DO equations in nonscattering and isotropic scattering media. Unlike the standard weighted diamond difference scheme, the new algorithm achieves local convergence in the case of discontinuous angular flux across the singular characteristics. The method also significantly reduces the error for problems where the angular flux presents discontinuous spatial derivatives across these lines. For purposes of testing the performance of the new method, the method of manufactured solutions is used to generate analytical reference solutions that permit accurate estimation of the local error in case of discontinuous flux.
