Earthquake early warning systems based on low-cost ground motion sensors: A systematic literature review

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Natural and Technological Hazards in Urban Areas

Natural hazard events and technological accidents are separate causes of environmental impacts. Natural hazards are physical phenomena active in geological times, whereas technological hazards result from actions or facilities created by humans. In our time, combined natural and man-made hazards have been induced. Overpopulation and urban development in areas prone to natural hazards increase the impact of natural disasters worldwide. Additionally, urban areas are frequently characterized by intense industrial activity and rapid, poorly planned growth that threatens the environment and degrades the quality of life. Therefore, proper urban planning is crucial to minimize fatalities and reduce the environmental and economic impacts that accompany both natural and technological hazardous events

Earthquake Early Warning System (EEWs) for the New Madrid Seismic Zone

Part 1: Research in the last decade on Earthquake Early Warning Systems (EEWSs) has undergone rapid development in terms of theoretical and methodological advances in real time data analysis, improved telemetry, and computer technology and is becoming a useful tool for practical real time seismic hazard mitigation. The main focus of this study is to undertake a feasibility study of an EEWS for the New Madrid Seismic Zone (NMSZ) from the standpoint of source location. Magnitude determination is addressed in a separate paper. The NMSZ covers a wide area with several heavily populated cities, vital infrastructures, and facilities located within a radius of less than 70 km from the epicenters of the 1811-1812 earthquakes. One of the challenges associated with the NMSZ is that while low to moderate levels of seismic activity are common, larger earthquakes are rare (i.e. there are no instrumentally recorded data for earthquakes with magnitudes greater than M5.5 in the NMSZ). We also recognize that it may not be realistic to provide early warning for all possible sources as is done on the west coast U.S. and we therefore focus on a specific source zone. We examine the stations within the NMSZ in order to answer the question What changes should be applied to the NMSZ network to make it suitable for earthquake early warning (EEW). We also explore needed changes to the Advanced National Seismic System (ANSS) Earthquake Monitoring System Real Time (AQMS RT) data acquisition system to make it useful for EEW. Our results show that EEW is feasible, though several technical challenges remain in incorporating its use with the present network.Part 2: Increasing vulnerability of metropolitan areas within stable continental regions (SCR), such as Memphis, TN and St. Louis, MO near the New Madrid Seismic Zone (NMSZ), to earthquakes and the very low probability level at which short term earthquake forecasting is possible make an earthquake early warning system (EEWS) a viable alternative for effective real-time risk reduction in these cities. In this study, we explore practical approaches to earthquake early warning (EEWS), and test the adaptability and potential of the real-time monitoring system in the NMSZ. We determine empirical relations based on amplitude and frequency magnitude proxies from the initial four seconds of the P-waveform records available from the Cooperative New Madrid Seismic Network (CNMSN) database for magnitude ????\u3e2.1. The amplitude-based proxies include low pass filtered peak displacement (Pd), peak velocity (Pv), and integral of the velocity squared (IV2), whereas the frequency-based proxies include predominant period (????????), characteristic period (????????), and log average period (????????????????). Very few studies have considered areas with lower magnitude events. With an active EEW system in the NMSZ, damage resulting from the catastrophic event, as witnessed in 1811-1812, may be mitigated in real-time

Investigating the cross-disciplinary components of earthquake early warning systems

Earthquake early warning (EEW) systems typically provide early estimates of earthquake magnitude, hypocentre location and/or ground-shaking estimates, as well as alerts ranging from a few seconds to tens of seconds, before the arrival of the damaging ground shaking at a target site. The warnings provided by these systems allow for the implementation of fast protection actions carried out by individuals like ‘drop, cover, and hold-on’, or the evacuation of buildings if the lead time is long enough. Nevertheless, the information and warning time provided by an EEW system could also be used by earthquake engineers as EEW seems to bear a powerful potential for the automatic activation of protection measures for infrastructure and critical systems, aiming at the reduction of risk due to earthquakes. Such automatic actions may include stopping elevators at the nearest floor, opening firehouse doors, slowing rapid-transit vehicles and high-speed trains to avoid accidents, to mention some. Few are the attempts found in literature about engineering applicability of EEW. This scarcity might be related to the fact that the real-time estimation of earthquake source parameters contains considerable uncertainty that may lead to potential economic losses if false or missed alarms are not avoided. However, different state-of-the-art studies regarding decision-making procedures for EEW have suggested more reliable approaches that can potentially reduce the uncertainty in the estimates provided by the system (e.g., earthquake source parameters and ground shaking), reducing the probability of triggering missed/false alarms, and therefore minimising the expected losses. The potential of designing new real-time advanced building protection applications for EEW is the motivation of this thesis. Mainly, two applications are considered: 1) Design of controlled structural systems using the early warning information, particularly, the use of semi-active devices denominated magnetorheological dampers. A control algorithm that governs the behaviour of the dampers is calibrated to obtain the most favourable response of a benchmark structure equipped with one damper. The results reveal that the developed EEW-based control algorithm can effectively reduce the expected loss of the considered case-study structure. 2) Prediction of shaking demands that can be expected in mid-rise to high-rise buildings, using a simplified continuum building model. A series of illustrative examples show how the newly developed prediction models can be efficiently used, in a Bayesian framework, for building-specific EEW applications based on the (acceleration) response in buildings, such as a) early warning of floor-shaking sensed by occupants; and b) control of elevator in buildings. The progress of technology and advances in the scientific understanding of engineering and seismology have promoted the rapid development of EEW systems around the world. However, their effectiveness is often limited as they lack the integration between their technical and social components. This thesis also aims at filling this gap to investigate which measures could be needed to increase the organisational resilience of local community stakeholders and the private sector. This topic is explored by implementing a mixed-method approach on the case study Mexico City (Mexico), that can be considered an area at risk due to the combination of high seismic hazard, structural and social vulnerabilities. This thesis shows the promising applicability of engineered applications of EEW systems and suggests a robust framework for the integration of the technical and societal components of EEW

Μελέτη, σχεδιασμός, κατασκευή και πειραματική διερεύνηση Σεισμογραφικού Συστήματος Έγκαιρης Προειδοποίησης

Οι σεισμοί ήταν πάντα ένα φαινόμενο που απασχολούσε την ανθρωπότητα ανά τους αιώνες λόγω της καταστροφικής τους δύναμης, πράγμα που επηρέαζε τις ίδιες τις κοινωνίες. Σήμερα η ραγδαία ανάπτυξη των υπολογιστικών συστημάτων, έχει δώσει την δυνατότητα στους επιστήμονες για ταχύτερη και αποδοτικότερη επεξεργασία των σεισμικών δεδομένων έτσι ώστε να μειώνονται οι επιπτώσεις ενός καταστρεπτικού σεισμού. Σε αυτή τη διατριβή παρουσιάζεται ο σχεδιασμός και η κατασκευή ενός σεισμογραφικού συστήματος έγκαιρης προειδοποίησης. Το παραπάνω σύστημα βασίζεται σε σταθμούς, κάθε ένας από τους οποίους είναι ένα φορητό ενσωματωμένο σύστημα χαμηλής κατανάλωσης, εξοπλισμένο με τους αισθητήρες χαμηλού κόστους, και με πολυπύρηνο επεξεργαστή, ώστε να εκτελεί υπολογισμούς τοπικά και σε πραγματικό χρόνο. Με αυτόν τον τρόπο, και λόγω της ασύρματης επικοινωνίας των σταθμών, μια περιοχή μπορεί να παρακολoυθείται εύκολα και γρήγορα, αφού η παρουσία του εξυπηρετητή αλλάζει ρόλο, και πλέον δεν χρησιμοποιείται για την έκδοση των προειδοποιήσεων, αλλά για τον υπολογισμό του επικέντρου και του μεγέθους του σεισμού.Earthquakes have always been a phenomenon that was observed by mankind throughout the centuries because of their destructive power, as they directly affect societies. Today, with the rapid development of computer systems, scientists have the opportunity for faster and more efficient processing of seismic data, so that the effects of a devastating earthquake can be mitigated. In this thesis the design and construction of a seismic early warning system is presented. This system is based on nodes, wherein each node is a portable low-power embedded system, equipped with low cost sensors, and processing power capable to perform calculations locally and in real time. In this way, and due to the fact that the nodes are being wirelessly communicating, a region can be monitored easily. The main application server now serves a different role, not for issuing the earthquake warning, but for calculating the location and the magnitude of the earthquake

A formal agent-based personalised mobile system to support emergency response

Communication may be seen as a process of sending and accepting information among individuals. It is a vital part of emergency response management, sharing the information of situations, victims, family and friends, rescue organisations and others. The obtained contextual information during a disaster event, however, is often dynamic, partial and may be conflicting with each other. Current communication strategies and solutions for emergency response have limitations - in that they are often designed to support information sharing between organisations and not individuals. As a result, they are often not personalisable. They also cannot make use of opportunistic resources, e.g. people nearby the disaster-struck areas that are ready to help but are not a part of any organisation. However, history has told us such people are often the first responders that provide the most immediate and useful help to the victims. On the other hand, the advanced and rich capabilities of mobile smartphones have become one of the most interesting topics in the field of mobile technologies and applied science. It is especially interesting when it can be expanded to become an effective emergency response tool to discover affected people and connect them with the first responders and their families, friends and communities. At present, research on emergency response is ineffective for handling large-scale disasters where professional rescuers could not reach victims in disaster struck-areas immediately. This is because current approaches are often built to support formal emergency response teams and organizations. Individual emergency response efforts, e.g. searching for missing people (inc. families and friends), are often web-based applications that are also not effective. Other works focus on sensory development that lacks integrated search and rescue approaches. In this thesis, I developed a distributed and personalisable Mobile Kit Disaster Assistant (MKA) system that is underpinned by a formal foundation. It aims at gathering emergency response information held by multiple resources before, during and after a large-scale disaster. As a result, contextual and background information based on a formal framework would be readily available, if a disaster indeed strikes. To this end, my core contribution is to provide a structural formal framework to encapsulate important information that is used to support emergency response at a personal level. Several (conceptual) structures were built to allow an individual to express his/her own individual circumstances, inc. relationships with others and health status that will determine how he/she may communicate with others. The communication framework is consisting of several new components: a rich and holistic Emergency Response Communication Framework, a newly developed Communication and Tracking Ontology (CTO), a newly devised Emergency Response Agent Communication Language (ER-ACL) and a brand-new Emergency Response Agent Communication Protocol (ER-ACP). I have framed the emergency response problem as a multi-agent problem where each smartphone would act as an agent for its user; each user would take on a role depending on requirements and/or the tasks at hand and the above framework is aimed to be used within a peer to peer distributed multiagent system (MAS) to assist emergency response efforts. Based on this formal framework, I have developed a mobile application, the MKA system, to capture important features of EM and to demonstrate the practicalities and value of the proposed formal framework. This system was carefully evaluated by both domain experts and potential users of targeted user groups using both qualitative and quantitative approaches. The overall results are very encouraging. Evaluators appreciated the importance of the tool and believe such tools are vital in saving lives – that is applicable for large-scale disasters as well as for individual life-critical events