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Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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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Securing the advanced reactor fleet
Physical protection accounts for a significant portion of a nuclear power plant’s operational costs. As the U.S. moves toward smaller and safer advanced reactors, similar protection strategies could prove cost prohibitive. For tomorrow’s small modular reactors and microreactors, security costs must remain appropriate to the size of the reactor for economical operation.
Dong Hoon Kim, Gwang Seop Son, Choul Woong Son, Dong Young Lee
Nuclear Technology | Volume 189 | Number 1 | January 2015 | Pages 87-102
Technical Paper | Nuclear Plant Operations and Control | doi.org/10.13182/NT13-142
Articles are hosted by Taylor and Francis Online.
This paper presents the architecture of the reactor protection system (RPS) in a nuclear integrated safety system (NISS) and describes the evaluation and analysis of reliability for NISS-RPS using the Markov model. NISS-RPS has four-channel redundancy like existing digital RPSs. However, a channel is configured based on triple modular redundancy and can be reconfigured on detecting faults. To analyze and evaluate the reliability of NISS-RPS, the Markov model for NISS-RPS and RPSs that are in operation or under construction in Korea were developed. Their reliability was evaluated and analyzed using the models. From the reliability analyses for NISS-RPS, it was observed that the failure rate of each module in NISS-RPS should be <2 × 10−5/hour, and the mean time to failure (MTTF) is ∼20 000 hours, which is two times better than the MTTF requirement of 10 000 hours. The MTTF average increase rate, which depends on the fault coverage factor (FCF) increment, ΔMTTF/ΔFCF, is 1850 hours/0.1. The results of comparison with other RPSs show that the reliability of NISS-RPS is at least 1.5 times better than that of the other three types of RPS architecture, and the MTTF is at least 14 months longer than that of the other types.