scholarly journals Estimating Parametric Line-Source Models With Electroencephalography

2006 ◽  
Vol 53 (11) ◽  
pp. 2156-2165 ◽  
Author(s):  
Nannan Cao ◽  
I.S. Yetik ◽  
A. Nehorai ◽  
C.H. Muravchik ◽  
J. Haueisen
Keyword(s):  
Line Source ◽  
Parametric Line ◽  
Source Models

Comparative study of line source models for estimating lead levels due to vehicular traffic in Delhi

1995 ◽  
Vol 10 (4) ◽  
pp. 289-299 ◽  
Author(s):  
P. Goyal ◽  
M.P. Singh ◽  
T.K. Bandopadhyay ◽  
T.V.B.P.S.Rama Krishna
Keyword(s):  
Comparative Study ◽  
Line Source ◽  
Vehicular Traffic ◽  
Source Models ◽  
Lead Levels

scholarly journals Real-Time Characterization of Finite Rupture and Its Implication for Earthquake Early Warning: Application of FinDer to Existing and Planned Stations in Southwest China

2021 ◽  
Vol 9 ◽  
Author(s):  
Jiawei Li ◽  
Maren Böse ◽  
Yu Feng ◽  
Chen Yang
Keyword(s):  
Real Time ◽  
Early Warning ◽  
Line Source ◽  
Average Distance ◽  
Strong Motion ◽  
Earthquake Early Warning ◽  
Time Data ◽  
Yunnan Region ◽  
Motion Time ◽  
Source Models

Earthquake early warning (EEW) not only improves resilience against the risk of earthquake disasters, but also provides new insights into seismological processes. The Finite-Fault Rupture Detector (FinDer) is an efficient algorithm to retrieve line-source models of an ongoing earthquake from seismic real-time data. In this study, we test the performance of FinDer in the Sichuan-Yunnan region (98.5oE–106.0oE, 22.0oN–34.0oN) of China for two datasets: the first consists of seismic broadband and strong-motion records of 58 earthquakes with 5.0 ≤ MS ≤ 8.0; the second comprises additional waveform simulations at sites where new stations will be deployed in the near future. We utilize observed waveforms to optimize the simulation approach to generate ground-motion time series. For both datasets the resulting FinDer line-source models agree well with the reported epicenters, focal mechanisms, and finite-source models, while they are computed faster compared to what traditional methods can achieve. Based on these outputs, we determine a theoretical relation that can predict for which magnitudes and station densities FinDer is expected to trigger, assuming that at least three neighboring stations must have recorded accelerations of 4.6 cm/s2 or more. We find that FinDer likely triggers and sends out a report, if the average distance between the epicenter and the three closest stations, Depi, is equal or smaller than log10 (Ma + b) + c, where a = 1.91, b = 5.93, and c = 2.34 for M = MW ≥ 4.8, and c = 2.49 for M = MS ≥ 5.0, respectively. If the data used in this study had been available in real-time, 40–70% of sites experiencing seismic intensities of V-VIII (on both Chinese and MMI scales) and 20% experiencing IX-X could have been issued a warning 5–10 s before the S-wave arrives. Our offline tests provide a useful reference for the planned installation of FinDer in the nationwide EEW system of Chinese mainland.

PERFORMANCE EVALUATION OF GAUSSIAN BASED LINE SOURCE MODELS AT URBAN ROADWAYS IN THE BANGALORE CITY

2004 ◽  
Vol 3 (3) ◽  
pp. 465-475 ◽  
Author(s):  
Shiva Nagendra ◽  
Megha Prakash ◽  
Renny Monilal ◽  
Mukesh Khare
Keyword(s):  
Performance Evaluation ◽  
Line Source ◽  
Bangalore City ◽  
Source Models

CORRECTION FACTORS FOR MORE ACCURATE ESTIMATES OF EXPOSURE RATES NEAR RADIOACTIVE PATIENTS: EXPERIMENTAL, POINT, AND LINE SOURCE MODELS

2007 ◽  
Vol 93 (6) ◽  
pp. 678-688 ◽  
Author(s):  
J Willegaignon ◽  
Maria I. C. Guimarães ◽  
Michael G. Stabin ◽  
Marcelo T. Sapienza ◽  
Luiz F. Malvestiti ◽  
...  
Keyword(s):  
Line Source ◽  
Experimental Point ◽  
Correction Factors ◽  
Source Models

Estimating Rupture Dimensions of Three Major Earthquakes in Sichuan, China, for Early Warning and Rapid Loss Estimates

2020 ◽  
Vol 110 (2) ◽  
pp. 920-936 ◽  
Author(s):  
Jiawei Li ◽  
Maren Böse ◽  
Max Wyss ◽  
David J. Wald ◽  
Alexandra Hutchison ◽  
...  
Keyword(s):  
Real Time ◽  
Early Warning ◽  
Line Source ◽  
Source Parameters ◽  
Strong Motion ◽  
Preventive Action ◽  
Fault Rupture ◽  
S Wave ◽  
Finite Fault ◽  
Source Models

ABSTRACT Large earthquakes, such as Wenchuan in 2008, Mw 7.9, Sichuan, China, provide an opportunity for earthquake early warning (EEW), as many heavily shaken areas are far (∼50  km) from the epicenter and warning times could be sufficient (≥5  s) to take preventive action. On the other hand, earthquakes with magnitudes larger than ∼M 6.5 are challenging for EEW because source dimensions need to be defined to adequately estimate shaking. Finite-fault rupture detector (FinDer) is an approach to identify fault rupture extents from real-time seismic records. In this study, we playback local and regional onscale strong-motion waveforms of the 2008 Mw 7.9 Wenchuan, 2013 Mw 6.6 Lushan, and 2017 Mw 6.5 Jiuzhaigou earthquakes to study the performance of FinDer for the current layout of the China Strong Motion Network. Overall, the FinDer line-source models agree well with the observed spatial distribution of aftershocks and models determined from waveform inversion. However, because FinDer models are constructed to characterize seismic ground motions (as needed for EEW) instead of source parameters, the rupture length can be overestimated for events radiating high levels of high-frequency motions. If the strong-motion data used had been available in real time, 50%–80% of sites experiencing intensity modified Mercalli intensity IV–VII (light to very strong) and 30% experiencing VIII–IX (severe to violent) could have been issued a warning with 10 and 5 s, respectively, before the arrival of the S wave. We also show that loss estimates based on the FinDer line source are more accurate compared to point-source models. For the Wenchuan earthquake, for example, they predict a four to six times larger number of fatalities and injured, which is consistent with official reports. These losses could be provided 1/2∼3  hr faster than if they were based on more complex inversion rupture models.

scholarly journals How Reliable Are Standard Thermal Response Tests? An Assessment Based on Long-Term Thermal Response Tests Under Different Operational Conditions

Energies ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 3347 ◽  
Author(s):  
Javier Urchueguía ◽  
Lenin-Guillermo Lemus-Zúñiga ◽  
Jose-Vicente Oliver-Villanueva ◽  
Borja Badenes ◽  
Miguel Pla ◽  
...  
Keyword(s):  
Groundwater Flow ◽  
Line Source ◽  
Thermal Response ◽  
Parameter Estimates ◽  
Test Duration ◽  
Operational Conditions ◽  
Source Models ◽  
Finite Line ◽  
Heat Injection ◽  
Finite Line Source

In this contribution, we analyze the results of a number of thermal response test (TRT) experiments performed during several years at the same location at our university campus in Valencia (Spain), a permeable saturated soil area with possible groundwater flow conditions. A combination of different heat injection rates, TRT operation times of up to 32 days, and various methods for parameter estimation of ground thermal properties have been applied to study their influence on the result and accuracy of TRTs. Our main objective has been to experimentally quantify the influence of groundwater flow heat advection using moving infinite and finite line-source theories, as well as to analyze the influence of factors such as test duration, sensor accuracy, and external thermal influences. We have shown that the traditionally used infinite and finite line-source models, as well as the moving line-source models, can accurately represent experimental temperature evolution, but that there are many caveats regarding the significance parameters extracted and its reproducibility and stability. These features can be improved if data from the first test days are disregarded for the analysis, obtaining a much faster convergence to the definitive soil parameter estimates, including the effective Péclet number that represents groundwater flow in our particular case.

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