The Experts below are selected from a list of 66180 Experts worldwide ranked by ideXlab platform
Emile A Okal - One of the best experts on this subject based on the ideXlab platform.
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gps for real time earthquake source determination and tsunami Warning Systems
Journal of Geodesy, 2009Co-Authors: G Blewitt, Corne Kreemer, William C Hammond, Hanspeter Plag, Seth Stein, Emile A OkalAbstract:We identify the key design aspects of a GPS-based system (and in the future, GNSS-based Systems) that could contribute to real-time earthquake source determination and tsunami Warning Systems. Our approach is based on models of both transient and permanent displacement of GPS stations caused by large earthquakes, while considering the effect of GPS errors on inverted earthquake source parameters. Our main conclusions are that (1) the spatial pattern, magnitude, and timing of permanent displacement of GPS stations can be inverted for the earthquake source and so predict the 3D displacement field of the ocean bottom, thus providing the initial conditions for tsunami models, and (2) there are no inherently limiting factors arising from real-time orbit and positioning errors, provided sufficient near-field GPS stations are deployed. This signal could be readily exploited by GPS networks currently in place, and will be facilitated by the IGS Real-Time Project as it comes to fruition.
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rapid determination of earthquake magnitude using gps for tsunami Warning Systems
Geophysical Research Letters, 2006Co-Authors: G Blewitt, Corne Kreemer, William C Hammond, Hanspeter Plag, Seth Stein, Emile A OkalAbstract:[1] The 26 December 2004 Sumatra earthquake (Mw 9.2–9.3) generated the most deadly tsunami in history. Yet within the first hour, the true danger of a major oceanwide tsunami was not indicated by seismic magnitude estimates, which were far too low (Mw 8.0–8.5). This problem relates to the inherent saturation of early seismic-wave methods. Here we show that the earthquake's true size and tsunami potential can be determined using Global Positioning System (GPS) data up to only 15 min after earthquake initiation, by tracking the mean displacement of the Earth's surface associated with the arrival of seismic waves. Within minutes, displacements of >10 mm are detectable as far away as India, consistent with results using weeks of data after the event. These displacements imply Mw 9.0 ± 0.1, indicating a high tsunami potential. This suggests existing GPS infrastructure could be developed into an effective component of tsunami Warning Systems.
G Blewitt - One of the best experts on this subject based on the ideXlab platform.
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gps for real time earthquake source determination and tsunami Warning Systems
Journal of Geodesy, 2009Co-Authors: G Blewitt, Corne Kreemer, William C Hammond, Hanspeter Plag, Seth Stein, Emile A OkalAbstract:We identify the key design aspects of a GPS-based system (and in the future, GNSS-based Systems) that could contribute to real-time earthquake source determination and tsunami Warning Systems. Our approach is based on models of both transient and permanent displacement of GPS stations caused by large earthquakes, while considering the effect of GPS errors on inverted earthquake source parameters. Our main conclusions are that (1) the spatial pattern, magnitude, and timing of permanent displacement of GPS stations can be inverted for the earthquake source and so predict the 3D displacement field of the ocean bottom, thus providing the initial conditions for tsunami models, and (2) there are no inherently limiting factors arising from real-time orbit and positioning errors, provided sufficient near-field GPS stations are deployed. This signal could be readily exploited by GPS networks currently in place, and will be facilitated by the IGS Real-Time Project as it comes to fruition.
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rapid determination of earthquake magnitude using gps for tsunami Warning Systems
Geophysical Research Letters, 2006Co-Authors: G Blewitt, Corne Kreemer, William C Hammond, Hanspeter Plag, Seth Stein, Emile A OkalAbstract:[1] The 26 December 2004 Sumatra earthquake (Mw 9.2–9.3) generated the most deadly tsunami in history. Yet within the first hour, the true danger of a major oceanwide tsunami was not indicated by seismic magnitude estimates, which were far too low (Mw 8.0–8.5). This problem relates to the inherent saturation of early seismic-wave methods. Here we show that the earthquake's true size and tsunami potential can be determined using Global Positioning System (GPS) data up to only 15 min after earthquake initiation, by tracking the mean displacement of the Earth's surface associated with the arrival of seismic waves. Within minutes, displacements of >10 mm are detectable as far away as India, consistent with results using weeks of data after the event. These displacements imply Mw 9.0 ± 0.1, indicating a high tsunami potential. This suggests existing GPS infrastructure could be developed into an effective component of tsunami Warning Systems.
Vasily V Titov - One of the best experts on this subject based on the ideXlab platform.
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evolution of tsunami Warning Systems and products
Philosophical Transactions of the Royal Society A, 2015Co-Authors: E N Bernard, Vasily V TitovAbstract:Each year, about 60 000 people and $4 billion (US$) in assets are exposed to the global tsunami hazard. Accurate and reliable tsunami Warning Systems have been shown to provide a significant defence for this flooding hazard. However, the evolution of Warning Systems has been influenced by two processes: deadly tsunamis and available technology. In this paper, we explore the evolution of science and technology used in tsunami Warning Systems, the evolution of their products using Warning technologies, and offer suggestions for a new generation of Warning products, aimed at the flooding nature of the hazard, to reduce future tsunami impacts on society. We conclude that coastal communities would be well served by receiving three standardized, accurate, real-time tsunami Warning products, namely (i) tsunami energy estimate, (ii) flooding maps and (iii) tsunami-induced harbour current maps to minimize the impact of tsunamis. Such information would arm communities with vital flooding guidance for evacuations and port operations. The advantage of global standardized flooding products delivered in a common format is efficiency and accuracy, which leads to effectiveness in promoting tsunami resilience at the community level. Language: en
Sriram Ramgopal - One of the best experts on this subject based on the ideXlab platform.
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seizure detection seizure prediction and closed loop Warning Systems in epilepsy
Epilepsy & Behavior, 2014Co-Authors: Sriram Ramgopal, Sigride Thomesouza, Michele Jackson, Navah Ester Kadish, Ivan Sanchez Fernandez, Jacquelyn Klehm, William J BoslAbstract:article i nfo Nearly one-third of patients with epilepsy continue to have seizures despite optimal medication management. Systems employed to detect seizures may have the potential to improve outcomes in these patients by allowing more tailored therapies and might, additionally, have a role in accident and SUDEP prevention. Automated sei- zure detection and prediction require algorithms which employ feature computation and subsequent classifica- tion. Over the last few decades, methods have been developed to detect seizures utilizing scalp and intracranial EEG, electrocardiography, accelerometry and motion sensors, electrodermal activity, and audio/video captures. To date, itisunclear which combination of detection technologiesyieldsthe best results,and approaches may ul- timately need to be individualized. This review presents an overview of seizure detection and related prediction methods and discusses their potential uses in closed-loop Warning Systems in epilepsy.
Corne Kreemer - One of the best experts on this subject based on the ideXlab platform.
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gps for real time earthquake source determination and tsunami Warning Systems
Journal of Geodesy, 2009Co-Authors: G Blewitt, Corne Kreemer, William C Hammond, Hanspeter Plag, Seth Stein, Emile A OkalAbstract:We identify the key design aspects of a GPS-based system (and in the future, GNSS-based Systems) that could contribute to real-time earthquake source determination and tsunami Warning Systems. Our approach is based on models of both transient and permanent displacement of GPS stations caused by large earthquakes, while considering the effect of GPS errors on inverted earthquake source parameters. Our main conclusions are that (1) the spatial pattern, magnitude, and timing of permanent displacement of GPS stations can be inverted for the earthquake source and so predict the 3D displacement field of the ocean bottom, thus providing the initial conditions for tsunami models, and (2) there are no inherently limiting factors arising from real-time orbit and positioning errors, provided sufficient near-field GPS stations are deployed. This signal could be readily exploited by GPS networks currently in place, and will be facilitated by the IGS Real-Time Project as it comes to fruition.
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rapid determination of earthquake magnitude using gps for tsunami Warning Systems
Geophysical Research Letters, 2006Co-Authors: G Blewitt, Corne Kreemer, William C Hammond, Hanspeter Plag, Seth Stein, Emile A OkalAbstract:[1] The 26 December 2004 Sumatra earthquake (Mw 9.2–9.3) generated the most deadly tsunami in history. Yet within the first hour, the true danger of a major oceanwide tsunami was not indicated by seismic magnitude estimates, which were far too low (Mw 8.0–8.5). This problem relates to the inherent saturation of early seismic-wave methods. Here we show that the earthquake's true size and tsunami potential can be determined using Global Positioning System (GPS) data up to only 15 min after earthquake initiation, by tracking the mean displacement of the Earth's surface associated with the arrival of seismic waves. Within minutes, displacements of >10 mm are detectable as far away as India, consistent with results using weeks of data after the event. These displacements imply Mw 9.0 ± 0.1, indicating a high tsunami potential. This suggests existing GPS infrastructure could be developed into an effective component of tsunami Warning Systems.