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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Remembering ANS member Gil Brown
Brown
The nuclear community is mourning the loss of Gilbert Brown, who passed away on July 11 at the age of 77 following a battle with cancer.
Brown, an American Nuclear Society Fellow and an ANS member for nearly 50 years, joined the faculty at Lowell Technological Institute—now the University of Massachusetts–Lowell—in 1973 and remained there for the rest of his career. He eventually became director of the UMass Lowell nuclear engineering program. After his retirement, he remained an emeritus professor at the university.
Sukesh Aghara, chair of the Nuclear Engineering Department Heads Organization, noted in an email to NEDHO members and others that “Gil was a relentless advocate for nuclear energy and a deeply respected member of our professional community. He was also a kind and generous friend—and one of the reasons I ended up at UMass Lowell. He served the university with great dedication. . . . Within NEDHO, Gil was a steady presence and served for many years as our treasurer. His contributions to nuclear engineering education and to this community will be dearly missed.”
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.
