西安电子科技大学 first passage of fractional-derivative stochastic systems with power-form...
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First Passage of Fractional-derivative Stochastic Systems with Power-form
Restoring Force1)Wei. Li (李伟 ), 2)Natasa. Trisovic
1)School of Mathematics and Statistics, Xidian University, China2)Faculty of Mechanical Engineering, University of Belgrade, Serbia
04/20/23
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Part 1 Background and Introduction
Part 2 Mathematical model and formulations
Part 3 BK equation and GP equation associated with first-passagePart 4 Numerical results and Monte-Carlo simulation
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Background of Stochastic Dynamical System
Background
• Whether the structures can keep safe and
stable?
•Is it possible to break down during the
vibration?
•How much probability the structures can
survive from stochastic vibration?
SDSDSS
DampiDampingng
RestorinRestoring forceg force
Random Random excitatioexcitatio
nn
Fractional Fractional derivative derivative
IntegerInteger
orderorder
Power-Power-formform
polynomipolynomialal
Gaussian Gaussian whitewhite
Background
•R. L. Bagley, P. J. Torvik. (1980)•Ivana Kovacic, Zvonko Rakaric (2012, 2013)
whitewhite
colorcolor
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Background
Fractional derivative has been successfully used in
• Environmental Engineering;
• Viscoelasticity Material;
• Biomedical Science
• Vibrated dynamical systems.
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L. C. Chen, W. Q. Zhu. ——fractional derivative damping——stochastic averaging method ——Stochastic jump and bifurcation
•Z. L. Huang, X. L. Jin——fractional derivative damping——stochastic averaging method——stationary response and stability•P. D. Spanos, G. I. Evangelatos——fractional derivative restoring force——time domain simulation and statistical linearization——response
Applications in SDS
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Aims to determine the probability that the response of a randomly excited dynamical system reaches the boundary of a bounded domain of state space within its lifetime.
First Passage
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Our Work
Fractional derivative
Power-formrestoring force
Gaussianexcitation
First passage of Stochastic dynamical
system
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Mathematical model
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0( ) ( ) ( )
tt a d t
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Reliability function
Energy process H(t) of the system
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Reliability function satisfies a Backward Kolmogorov (BK) equation
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Moment of first-passage time
Satisfies the Generalized Pontryagin (GP)
equation
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Example
0 0.05, 3.5, 11 0.05,D 1,c 5,cH
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First passage of SDS with fractional derivative and power-form restoring fore
Conclusions
Bigger boundary value of safe domain and strong nonlinearity of restoring force are advantageous to improve system reliability
Monte-Carlo simulation proved that the proposed methods and procedures are correct and efficient.
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Thank you for your attention!