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ANS hosts webinar on criticality safety standards
A diagram depicting the NRC’s regulatory structure for nuclear criticality safety. (Image: Oak Ridge National Laboratory)
The American Nuclear Society’s Risk-informed, Performance-based Principles and Policy Committee (RP3C) held another presentation in its monthly Community of Practice (CoP) series last month. RP3C chair Steven Krahn opened the meeting with brief introductory remarks about the importance of risk-informed, performance based (RIPB) decision-making and the need for new approaches to nuclear design that go beyond conventional and deterministic methods.
W. Seifritz
Nuclear Technology | Volume 7 | Number 6 | December 1969 | Pages 513-522
Reactor | doi.org/10.13182/NT69-A28370
Articles are hosted by Taylor and Francis Online.
A newly developed special two-detector cross-correlation experiment of zero-power reactor-noise analysis is applied to determining characteristic kinetic-reactor parameters. This method-called polarity correlation in the frequency domain-is based on the detailed analysis of the stochastic Coherence Function, in contrast to the analysis of auto and/or cross power spectral density functions. The coherence function is easily obtained by polarity correlation of two filtered random-neutron-noise signals simultaneously sampled in a reactor system using neutronsensitive detectors in the current mode of operation. The advantage and the progress in using this technique is both its simplicity and the automatic elimination of the equipment frequency response, which is of special importance when analyzing fast-reactor-noise spectra. A series of prompt-neutron-decay constant measurements was performed on several configurations of the STARK and SNEAK facilities. Moreover, special attention and effort is dedicated to reactivity shutdown measurements by the polarity correlation method. An on-line reactivity meter is described which is particularly suited to making reactivity measurements in large plutonium fueled reactors. Shutdown reactivity measurements were performed down to -8 dollars.