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Decommissioning & Environmental Sciences
The mission of the Decommissioning and Environmental Sciences (DES) Division is to promote the development and use of those skills and technologies associated with the use of nuclear energy and the optimal management and stewardship of the environment, sustainable development, decommissioning, remediation, reutilization, and long-term surveillance and maintenance of nuclear-related installations, and sites. The target audience for this effort is the membership of the Division, the Society, and the public at large.
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Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
Standards Program
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
Vogtle-3 shuts down for valve issue
One of the new Vogtle units in Georgia was shut down unexpectedly on Monday last week for a valve issue that has since been investigated and repaired. According to multiple local news outlets, Georgia Power reported on July 17 that Unit 3 was back in service.
Southern Company spokesperson Jacob Hawkins confirmed that Vogtle-3 went off line at 9:25 p.m. local time on July 8 “due to lowering water levels in the steam generators caused by a valve issue on one of the three main feedwater pumps.”
Luciano Burgazzi
Nuclear Technology | Volume 161 | Number 1 | January 2008 | Pages 1-7
Technical Paper | Reactor Safety | doi.org/10.13182/NT08-A3908
Articles are hosted by Taylor and Francis Online.
The focus of the present study is passive system reliability assessment, with reference to the thermal-hydraulic passive systems (i.e., relying on natural circulation). An approach based on system-relevant performance parameters is introduced to provide system-significant availability and reliability figures, within a reliability physics framework.The method exploits the fact that for thermal-hydraulic passive systems to perform as expected to accomplish the required mission, parameters must lie between certain limits according to defined safety criteria. Some relevant physical parameters are worth considering as significant indicators of thermal-hydraulic passive system performance, for instance coolant flow or exchanged thermal power. Within this methodology, the selected representative parameters defining the system performance are properly modeled through the construction of joint probability functions in order to assess the correspondent functional reliability. The application of the methodology to a realistic passive system design is illustrated.The results are shown to point out the relevance of the passive system functional reliability aspects with respect to the classical mechanical component malfunctions, serving as a foundation for continuous improvement of the passive system reliability assessment process.This paper aims to remedy some of the limitations following on from applying the functional reliability approach to the passive system reliability problem, as highlighted in an earlier paper [Nuclear Technology, Vol. 144, p. 145 (Nov. 2003)]. This concerns essentially the assumption of independence between the marginal distributions to construct the joint probability distributions to evaluate system reliability.