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Development of an earthquake early warning system using real-time strong motion signals

Wu, Yih-Min and Kanamori, Hiroo (2008) Development of an earthquake early warning system using real-time strong motion signals. Sensors, 8 (1). pp. 1-9. ISSN 1424-8220. doi:10.3390/s8010001.

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As urbanization progresses worldwide, earthquakes pose serious threat to lives and properties for urban areas near major active faults on land or subduction zones off shore. Earthquake Early Warning (EEW) can be a useful tool for reducing earthquake hazards, if the spatial relation between cities and earthquake sources is favorable for such warning and their citizens are properly trained to respond to earthquake warning messages. An EEW system forewarns an urban area of forthcoming strong shaking, normally with a few sec to a few tens of sec of warning time, i.e., before the arrival of the destructive S-wave part of the strong ground motion. Even a few second of advanced warning time will be useful for pre-programmed emergency measures for various critical facilities, such as rapid-transit vehicles and high-speed trains to avoid potential derailment; it will be also useful for orderly shutoff of gas pipelines to minimize fire hazards, controlled shutdown of high-technological manufacturing operations to reduce potential losses, and safe-guarding of computer facilities to avoid loss of vital databases. We explored a practical approach to EEW with the use of a ground-motion period parameter τ_c and a high-pass filtered vertical displacement amplitude parameter Pd from the initial 3 sec of the P waveforms. At a given site, an earthquake magnitude could be determined from τ_c and the peak ground-motion velocity (PGV) could be estimated from Pd. In this method, incoming strong motion acceleration signals are recursively converted to ground velocity and displacement. A P-wave trigger is constantly monitored. When a trigger occurs, τ_c and Pd are computed. The earthquake magnitude and the on-site ground-motion intensity could be estimated and the warning could be issued. In an ideal situation, such warnings would be available within 10 sec of the origin time of a large earthquake whose subsequent ground motion may last for tens of seconds.

Item Type:Article
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URLURL TypeDescription DOIArticle
Kanamori, Hiroo0000-0001-8219-9428
Additional Information:© 2008 by MDPI. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Received: 20 December 2007; Accepted: 5 January 2008; Published: 9 January 2008. The authors wish to thank the two anonymous reviewers for their constructive comments which helped improve the manuscript. This research was supported by the National Science Council of the Republic of China (NSC95-2625-Z-002-028, NSC95-2119-M-002-043-MY3) with TEC contribution number 00027. We would like to thank the NIED (Japan), Central Weather Bureau (Taiwan), and Southern California Earthquake Center for providing us with seismic data.
Funding AgencyGrant Number
National Science CouncilNSC95-2625-Z-002-028
National Science CouncilNSC95-2119-M-002-043-MY3
Subject Keywords:earthquake; early warning system; seismic hazard mitigation
Issue or Number:1
Record Number:CaltechAUTHORS:20141114-144307781
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Official Citation:Wu, Y.-M.; Kanamori, H. Development of an Earthquake Early Warning System Using Real-Time Strong Motion Signals. Sensors 2008, 8, 1-9.
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:51801
Deposited By: Tony Diaz
Deposited On:15 Nov 2014 00:56
Last Modified:10 Nov 2021 19:15

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