An Estimation Method for First Excursion Probability of Nonlinear System Using Maximum Response

2004 ◽  
Author(s):  
Shigeru Aoki
Keyword(s):  
Failure Modes ◽  
Damping Ratio ◽  
Estimation Method ◽  
Maximum Response ◽  
Estimation Methods ◽  
Mechanical Equipment ◽  
Primary System ◽  
Secondary System ◽  
Restoring Force ◽  
Excursion Probability

The secondary system such as pipings, tanks and other mechanical equipment are installed in the primary system such as building. The important secondary systems should be designed to maintain their function even if they are subjected to destructive earthquake excitations. First excursion failure is one of the most important failure modes. The secondary system has many nonlinear characteristics. In this paper, an estimation methods of the first excursion probability of the secondary system with gap and friction subjected to earthquake excitation is proposed. Restoring force with gap and friction force is equivalently linearized. When the tolerance level is normalized by the maximum response of the secondary system without gap and friction characteristics, variation of the first excursion probability is very small for various values of mass ratio of the secondary system to the primary system, the damping ratio and the natural period.

Estimation Method for First Excursion Probability of System With Collision Characteristic

2006 ◽  
Author(s):  
Shigeru Aoki
Keyword(s):  
Failure Modes ◽  
Estimation Method ◽  
Pressure Vessels ◽  
Expected Value ◽  
Maximum Response ◽  
Seismic Excitations ◽  
Nonlinear Characteristics ◽  
Tolerance Level ◽  
Piping Systems ◽  
Excursion Probability

Safety of structures subjected to seismic excitations should be evaluated in probabilistic manner. First excursion failure is one of the most important failure modes of structures. Many structures have nonlinear characteristics. Collision characteristic is one of the most common nonlinear characteristics observed in pressure vessels and piping systems. In this paper, an estimation method for the first excursion probability of structure with collision characteristic is proposed. The first excursion probability is the function of many parameters. It is shown that when the tolerance level is normalized by the expected value of the maximum response of the structures, the first excursion probability can be shown to be in dependent of many parameters.

Reliability of System With Hysteresis Loop Characteristic Subjected to Earthquake Excitations

2007 ◽  
Author(s):  
Shigeru Aoki
Keyword(s):  
Hysteresis Loop ◽  
Failure Modes ◽  
Estimation Method ◽  
Pressure Vessels ◽  
Nonlinear Characteristics ◽  
Tolerance Level ◽  
Piping Systems ◽  
Time Histories ◽  
Expected Values ◽  
Excursion Probability

Estimation of reliability of system subjected to earthquake excitations is important problem for aseismic design. Reliability of such system should be evaluated in probabilistic manner. First excursion failure is one of the most important failure modes of structures and one of a factor of reliability. Many structures have nonlinear characteristics. Hysteresis loop characteristic caused by plastic deformation is one of the most common nonlinear characteristics observed in pressure vessels and piping systems. In this paper, an estimation method for the first excursion probability of structure with hysteresis loop characteristic is proposed. The first excursion probability is the function of many parameters. First excursion probability is obtained by using artificial time histories. It is shown that when the tolerance level is normalized by the expected values of the maximum response of the structures, the first excursion probability can be shown independent of many parameters.

Reliability of System With Hysteresis Loop Characteristic Subjected to Earthquake Excitations

2009 ◽  
Vol 131 (4) ◽  
Author(s):  
Shigeru Aoki
Keyword(s):  
Hysteresis Loop ◽  
Failure Modes ◽  
Estimation Method ◽  
Pressure Vessels ◽  
Nonlinear Characteristics ◽  
Tolerance Level ◽  
Piping Systems ◽  
Time Histories ◽  
Expected Values ◽  
Excursion Probability

The estimation of reliability of system subjected to earthquake excitations is an important problem for aseismic design. The reliability of such system should be evaluated in probabilistic manner. The first excursion failure is one of the most important failure modes of structures and also one factor of reliability. Many structures have nonlinear characteristics. Hysteresis loop characteristic caused by plastic deformation is one of the most common nonlinear characteristics observed in pressure vessels and piping systems. In this paper, an estimation method for the first excursion probability of structure with hysteresis loop characteristic is proposed. The first excursion probability is the function of many parameters, which is obtained by using artificial time histories. It is shown that when the tolerance level is normalized by the expected values of the maximum response of the structures, the first excursion probability can be shown to be independent of many parameters.

Using The Fully Modified M Method In Estimating The Effect Of Cultivated Area On Barley Production In Iraq For The Period 1970-2018

2020 ◽  
Vol 2020 (66) ◽  
pp. 101-110
Author(s):  
. Azhar Kadhim Jbarah ◽  
Prof Dr. Ahmed Shaker Mohammed
Keyword(s):  
Regression Model ◽  
Moving Average ◽  
Estimation Method ◽  
Estimation Methods ◽  
Autoregressive Moving Average ◽  
Moving Average Models ◽  
Error Terms ◽  
Relationship Of ◽  
The Relationship ◽  
Barley Crop

The research is concerned with estimating the effect of the cultivated area of barley crop on the production of that crop by estimating the regression model representing the relationship of these two variables. The results of the tests indicated that the time series of the response variable values is stationary and the series of values of the explanatory variable were nonstationary and that they were integrated of order one ( I(1) ), these tests also indicate that the random error terms are auto correlated and can be modeled according to the mixed autoregressive-moving average models ARMA(p,q), for these results we cannot use the classical estimation method to estimate our regression model, therefore, a fully modified M method was adopted, which is a robust estimation methods, The estimated results indicate a positive significant relation between the production of barley crop and cultivated area.

scholarly journals Comparative Analysis of Kinect-Based and Oculus-Based Gaze Region Estimation Methods in a Driving Simulator

Sensors ◽  
2020 ◽  
Vol 21 (1) ◽  
pp. 26
Author(s):  
David González-Ortega ◽  
Francisco Javier Díaz-Pernas ◽  
Mario Martínez-Zarzuela ◽  
Míriam Antón-Rodríguez
Keyword(s):  
Virtual Reality ◽  
Comparative Analysis ◽  
Driving Simulator ◽  
Estimation Method ◽  
Estimation Methods ◽  
Gaze Estimation ◽  
Driving Simulators ◽  
Oculus Rift ◽  
Gaze Patterns ◽  
And Performance

Driver’s gaze information can be crucial in driving research because of its relation to driver attention. Particularly, the inclusion of gaze data in driving simulators broadens the scope of research studies as they can relate drivers’ gaze patterns to their features and performance. In this paper, we present two gaze region estimation modules integrated in a driving simulator. One uses the 3D Kinect device and another uses the virtual reality Oculus Rift device. The modules are able to detect the region, out of seven in which the driving scene was divided, where a driver is gazing at in every route processed frame. Four methods were implemented and compared for gaze estimation, which learn the relation between gaze displacement and head movement. Two are simpler and based on points that try to capture this relation and two are based on classifiers such as MLP and SVM. Experiments were carried out with 12 users that drove on the same scenario twice, each one with a different visualization display, first with a big screen and later with Oculus Rift. On the whole, Oculus Rift outperformed Kinect as the best hardware for gaze estimation. The Oculus-based gaze region estimation method with the highest performance achieved an accuracy of 97.94%. The information provided by the Oculus Rift module enriches the driving simulator data and makes it possible a multimodal driving performance analysis apart from the immersion and realism obtained with the virtual reality experience provided by Oculus.

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