Interperiod Correlation Model for Mexican Interface Earthquakes

2019 ◽  
Vol 35 (3) ◽  
pp. 1351-1365 ◽  
Author(s):  
Miguel A. Jaimes ◽  
Gabriel Candia
Keyword(s):  
Subduction Zones ◽  
Specific Model ◽  
Peak Ground Velocity ◽  
Correlation Model ◽  
Ground Acceleration ◽  
Mixed Effect ◽  
Ground Motion Model ◽  
Class B ◽  
Effect Regression ◽  
Mixed Effect Regression Model

This article presents a correlation model for pseudo-acceleration, peak ground acceleration, and peak ground velocity residuals using a database of Mexican subduction interface earthquakes at rock sites (NEHRP Class B). A mixed-effect regression model, a ground motion model, and 40 event recordings (418 records) with moment magnitude between five and eight were used to develop a magnitude-independent correlation model. This region-specific model yields consistently higher correlation values compared with similar studies developed for shallow crustal regions and other subduction zones worldwide, particularly for pseudo-acceleration values at distant periods. These results support the idea of using a region-specific and mechanism-specific correlation model for Mexico's subduction zone.

scholarly journals Lens densitometry for assessment and prediction of cataract progression after pars plana vitrectomy with C3F8-gas for retinal detachment

PLoS ONE ◽  
2021 ◽  
Vol 16 (7) ◽  
pp. e0254370
Author(s):  
Philipp Schindler ◽  
Luca Mautone ◽  
Eileen Bigdon ◽  
Vasyl Druchkiv ◽  
Martin Stefan Spitzer ◽  
...  
Keyword(s):  
Retinal Detachment ◽  
Regression Model ◽  
Pars Plana Vitrectomy ◽  
Quantitative Model ◽  
Average Deviation ◽  
Mixed Effect ◽  
Lens Opacification ◽  
Effect Regression ◽  
Pars Plana ◽  
Mixed Effect Regression Model

Purpose Lens opacification is a common complication after pars plana vitrectomy (PPV) and knowing its progression would facilitate consulting patients. The purpose of this study was to evaluate a quantitative model for lens-status-monitoring after PPV with C3F8 gas. Our model was evaluated in rhegmatogenous retinal detachment (RRD) patients of various age and lens densitometry (LD). Methods Data between March 2018 and March 2020 were evaluated retrospectively. LD measurements of the PentacamHR® Nucleus Staging mode (PNS) were used to quantify lens opacification over time. A mixed-effect regression model was designed, to enable LD predictions at any time postoperatively. Calculations were based on patient’s age and baseline LD as dependent variables. Six patients were randomly excluded during model development, to be used for testing its power afterwards. Results 34 patients (male 19 [55.9%], female 15 [44.1%]) matched the inclusion criteria. Average age was 58.5 years (32–77;±4.3) and average follow-up was 7.2 months (3,4–23.1;±1,8). Mean baseline LD of the treated and fellow eye before surgery were 10.9% (8.7%-14.8%;±0.8) and 10.7% (8.5%-14.1%;±0.6), respectively. Using our prediction model, LD values for the six pre-selected patients closely match the observed data with an average deviation of 1.07%. Conclusions Evaluation of age and baseline LD using a mixed-effect regression model might predict cataract progression in RRD patients treated with PPV and C3F8-gas. Such a tool could be considered during cataract surgery consultation in these patients.

NGA-Subduction research program

2021 ◽  
pp. 875529302110560
Author(s):  
Yousef Bozorgnia ◽  
Norman A Abrahamson ◽  
Sean K Ahdi ◽  
Timothy D Ancheta ◽  
Linda Al Atik ◽  
...  
Keyword(s):  
Ground Motion ◽  
Research Program ◽  
Epistemic Uncertainty ◽  
Specific Model ◽  
Peak Ground Velocity ◽  
Ground Acceleration ◽  
Motion Data ◽  
Motion Models ◽  
Aleatory Variability ◽  
Adjustment Factors

This article summarizes the Next Generation Attenuation (NGA) Subduction (NGA-Sub) project, a major research program to develop a database and ground motion models (GMMs) for subduction regions. A comprehensive database of subduction earthquakes recorded worldwide was developed. The database includes a total of 214,020 individual records from 1,880 subduction events, which is by far the largest database of all the NGA programs. As part of the NGA-Sub program, four GMMs were developed. Three of them are global subduction GMMs with adjustment factors for up to seven worldwide regions: Alaska, Cascadia, Central America and Mexico, Japan, New Zealand, South America, and Taiwan. The fourth GMM is a new Japan-specific model. The GMMs provide median predictions, and the associated aleatory variability, of RotD50 horizontal components of peak ground acceleration, peak ground velocity, and 5%-damped pseudo-spectral acceleration (PSA) at oscillator periods ranging from 0.01 to 10 s. Three GMMs also quantified “within-model” epistemic uncertainty of the median prediction, which is important in regions with sparse ground motion data, such as Cascadia. In addition, a damping scaling model was developed to scale the predicted 5%-damped PSA of horizontal components to other damping ratios ranging from 0.5% to 30%. The NGA-Sub flatfile, which was used for the development of the NGA-Sub GMMs, and the NGA-Sub GMMs coded on various software platforms, have been posted for public use.

A Markov mixed effect regression model for drug compliance

1998 ◽  
Vol 17 (20) ◽  
pp. 2313-2333 ◽  
Author(s):  
Pascal Girard ◽  
Terrence F. Blaschke ◽  
Helen Kastrissios ◽  
Lewis B. Sheiner
Keyword(s):  
Regression Model ◽  
Drug Compliance ◽  
Mixed Effect ◽  
Effect Regression ◽  
Mixed Effect Regression Model

scholarly journals The role of hyoid muscles in biotremor production in Chamaeleo calyptratus

2020 ◽  
Vol 223 (22) ◽  
pp. jeb227603
Author(s):  
Samuel M. Tegge ◽  
Christopher V. Anderson ◽  
Michael E. Smith ◽  
Steve Huskey
Keyword(s):  
Body Temperature ◽  
Muscle Activation ◽  
Mixed Effect ◽  
Anatomical Structures ◽  
Levator Scapulae ◽  
Effect Regression ◽  
Activation Data ◽  
Chamaeleo Calyptratus ◽  
Mixed Effect Regression Model

ABSTRACTThe production of biotremors has been described in veiled chameleons (Chamaeleo calyptratus), but the mechanism by which they are produced is unknown. We gathered muscle activation data via electromyography (EMG), with simultaneous recordings of biotremors using an accelerometer, to test for the role of hyoid muscles in biotremor production. We recorded a mean biotremor frequency of 150.87 Hz for females and 136.01 Hz for males. The durations of activity and the latencies to onset and offset for the M. sternohyoideus profundus (SP), M. sternohyoideus superficialis (SS), Mm. mandibulohyoideus (MH) and M. levator scapulae (LS) were all significantly correlated with biotremor durations and biotremor onset and offset, respectively. Linear mixed-effect regression model comparisons of biotremor duration indicated that models containing either the MH and/or the SP and LS account for the most variation in biotremor duration. Twitch times for the SP (100 ms) and the SS (132 ms) at field active body temperature, however, were individually too slow to produce the biotremors at the observed frequency without alteration after production by other anatomical structures. These results implicate the SP, SS, MH and LS in the production of biotremors, but the exact mechanism of production requires further study.

scholarly journals Constancy of the angle between the Frankfort horizontal plane and the sella-nasion line: A nine-year longitudinal study

2013 ◽  
Vol 84 (2) ◽  
pp. 286-291 ◽  
Author(s):  
Young Jae Huh ◽  
Kyung-Hoe Huh ◽  
Hong-Kyun Kim ◽  
Shin-Eun Nam ◽  
Hye Yoon Song ◽  
...  
Keyword(s):  
Longitudinal Study ◽  
Horizontal Plane ◽  
Annual Change ◽  
Mixed Effect ◽  
Effect Regression ◽  
The Mean ◽  
Frankfort Horizontal Plane ◽  
Mixed Effect Regression Model ◽  
Over Time ◽  
Observation Period

ABSTRACT Objective: To investigate the constancy of the angle between the Frankfort horizontal plane (FH) and the sella-nasion line (SN) using longitudinal data. Materials and Methods: Longitudinal lateral cephalometric data of 223 children (116 girls and 107 boys) from 6 to 14 years of age were used. The angle between FH and SN (SNFH), the distance from FH to the nasion (NFH), the distance from FH to the sella (SFH), and the differences between the NFH and SFH (Δ) were also measured. All data were analyzed statistically using independent t-tests and mixed-effect regression model analysis. Results: The mean SNFH values showed some minor fluctuations, ranging from 9.26° to 9.74° in girls and 8.45° to 8.95° in boys. The mean NFH and SFH values gradually increased according to age irrespective of sex. There were statistically significant differences by sex for all measurements at several ages. The annual change in SFH and Δ showed sexual dimorphism. Conclusions: There are variations among individuals in the angle between the FH and SN. However, within an individual, the angle does not vary significantly over time during the observation period.

A Far-Field Ground-Motion Model for the North Australian Craton from Plate-Margin Earthquakes

2021 ◽  
Author(s):  
Trevor I. Allen
Keyword(s):  
Ground Motion ◽  
Ground Motions ◽  
Peak Ground Velocity ◽  
Far Field ◽  
Motion Model ◽  
Ground Acceleration ◽  
Depth Dependence ◽  
Ground Motion Model ◽  
Plate Margin ◽  
Short Period

ABSTRACT The Australian territory is just over 400 km from an active convergent plate margin with the collision of the Sunda–Banda Arc with the Precambrian and Palaeozoic Australian continental crust. Seismic energy from earthquakes in the northern Australian plate-margin region are channeled efficiently through the low-attenuation North Australian craton (NAC), with moderate-sized (Mw≥5.0) earthquakes in the Banda Sea commonly felt in northern Australia. A far-field ground-motion model (GMM) has been developed for use in seismic hazard studies for sites located within the NAC. The model is applicable for hypocentral distances of approximately 500–1500 km and magnitudes up to Mw 8.0. The GMM provides coefficients for peak ground acceleration, peak ground velocity, and 5%-damped pseudospectral acceleration at 20 oscillator periods from 0.1 to 10 s. A strong hypocentral depth dependence is observed in empirical data, with earthquakes occurring at depths of 100–200 km demonstrating larger amplitudes for short-period ground motions than events with shallower hypocenters. The depth dependence of ground motion diminishes with longer spectral periods, suggesting that the relatively larger ground motions for deeper earthquake hypocenters may be due to more compact ruptures producing higher stress drops at depth. Compared with the mean Next Generation Attenuation-East GMM developed for the central and eastern United States (which is applicable for a similar distance range), the NAC GMM demonstrates significantly higher short-period ground motion for Banda Sea events, transitioning to lower relative accelerations for longer period ground motions.

Correlations of spectral accelerations in the Chilean subduction zone

2020 ◽  
Vol 36 (2) ◽  
pp. 788-805 ◽  
Author(s):  
Gabriel Candia ◽  
Alan Poulos ◽  
Juan Carlos de la Llera ◽  
Jorge G.F. Crempien ◽  
Jorge Macedo
Keyword(s):  
Subduction Zone ◽  
Subduction Zones ◽  
Peak Ground Velocity ◽  
Data Sets ◽  
Correlation Model ◽  
Crustal Earthquakes ◽  
Correlation Models ◽  
Spatially Distributed ◽  
Soil Site ◽  
Spectral Accelerations

The correlation between spectral accelerations is key in the construction of conditional mean spectra, the computation of vector-valued seismic hazard, and the assessment of seismic risk of spatially distributed systems, among other applications. Spectral correlations are highly dependent on the earthquake database used, and thus, region-specific correlation models have been developed mainly for earthquakes in western United States, Europe, Middle East, and Japan. Correlation models based on global data sets for crustal and subduction zones have also become available, but there is no consensus about their applicability on a specific region. This study proposes a new correlation model for 5% damped spectral accelerations and peak ground velocity in the Chilean subduction zone. The correlations obtained were generally higher than those observed from shallow crustal earthquakes and subduction zones such as Japan and Taiwan. The study provides two illustrative applications of the correlation model: (1) computation of conditional spectra for a firm soil site located in Santiago, Chile and (2) computation of bivariate hazard for spectral accelerations at two structural periods.

A ground-motion prediction model for small-to-moderate induced earthquakes for Central and Eastern United States

2021 ◽  
pp. 875529302110160
Author(s):  
Zoya Farajpour ◽  
Shahram Pezeshk
Keyword(s):  
United States ◽  
Ground Motion ◽  
Gulf Coast ◽  
Hazard Evaluation ◽  
Eastern United States ◽  
Induced Earthquakes ◽  
Ground Acceleration ◽  
Mixed Effect ◽  
Ground Motion Model ◽  
Tectonic Earthquakes

This study presents a new ground motion model (GMM) for small-to-moderate potentially induced earthquakes for Central and Eastern United States (CEUS). We used a hybrid empirical model as the base model, which was developed and calibrated for tectonic events in Central and Eastern North America (CENA) as part of the Next-generation Attenuation-East (NGA-East) project. We calibrated the base model using a comprehensive database of potentially induced ground motions with smaller magnitudes and shallower depths than tectonic earthquakes, excluding all earthquake events and stations within the Gulf Coast region. We determined the model functional form coefficients using a mixed-effect regression procedure. The proposed GMM is derived for the peak ground acceleration and response-spectral ordinates at periods ranging from 0.01 to 10.0s, moment magnitudes ranging from 3.0 to 5.8, and hypocentral distances up to 200km. The performance of the proposed GMM is evaluated through a set of comprehensive residual analyses. Furthermore, we compared the proposed GMM with recently published GMMs with the observed data for CEUS. The proposed GMM could apply in long-term and short-term US Geological Survey National Seismic Hazard Maps and for the hazard evaluation of induced seismicity.

Ground Motion Model for the Vertical-to-Horizontal (V/H) Ratios of PGA, PGV, and Response Spectra

2016 ◽  
Vol 32 (2) ◽  
pp. 951-978 ◽  
Author(s):  
Yousef Bozorgnia ◽  
Kenneth W. Campbell
Keyword(s):  
Ground Motion ◽  
Site Response ◽  
Hanging Wall ◽  
Strong Dependence ◽  
Response Spectra ◽  
Peak Ground Velocity ◽  
Motion Model ◽  
Fault Rupture ◽  
Ground Acceleration ◽  
Ground Motion Model

We present a ground motion model (GMM) for the vertical-to-horizontal (V/H) ratios of peak ground acceleration, peak ground velocity, and 5%-damped pseudo-acceleration response spectra at periods ranging from 0.01 s to 10 s. The V/H GMM includes formulations for the median V/H ratio and for the aleatory within-event, between-event, and total standard deviations. The V/H model is based on the GMMs we have developed for the vertical and “average” horizontal components of ground motion using a mathematical formation that accounts for the correlation between these two components. We validated the V/H model against the NGA-West2 empirical database. We consider our V/H model to be valid for worldwide shallow crustal earthquakes in active tectonic regions for moment magnitudes ranging from 3.3 to 8.5, depending on the style of faulting, and for fault rupture distances ranging from 0 km to 300 km. Our V/H model incorporates period-dependent effects of magnitude saturation, style of faulting, hypocentral depth, fault-rupture dip, geometric attenuation, regionally dependent anelastic attenuation and site response, hanging-wall geometry, and magnitude-dependent between-event and within-event aleatory variabilities. The V/H ratios predicted from the model show a strong dependence on spectral period and site response.

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