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941.
An experimental-numerical methodology is introduced to identify the parameters of a cohesive law of an adhesive layer within a joined assembly on the basis of kinematic data provided by digital image correlation. Non-conventional experiments on joined samples were designed to generate within the assembly and the adhesive film complex strain and stress states close to those expected in-service and up to complete debonding. The modeling is developed with reference to the observed sub-domain in which the experimental boundary conditions are prescribed. The nonlinear behavior of the adhesive layer is described as a finite-thickness interface endowed with a mixed-mode cohesive law whose parameters are identified so as to match at best the measured displacement field. 相似文献
942.
This paper studies how phase synchronization in complex networks
depends on random shortcuts, using the piecewise-continuous chaotic
Chua system as the nodes of the networks. It is found that for a
given coupling strength, when the number of random shortcuts is
greater than a threshold the phase synchronization is induced. Phase
synchronization becomes evident and reaches its maximum as the
number of random shortcuts is further increased. These phenomena
imply that random shortcuts can induce and enhance the phase
synchronization in complex Chua systems. Furthermore, the paper
also investigates the effects of the coupling strength and it is
found that stronger coupling makes it easier to obtain the
complete phase synchronization. 相似文献
943.
WANG Mao-Sheng 《理论物理通讯》2009,52(1):81-84
Effects of coupling distance on synchronization and coherence of chaotic neurons in complex networks are numerically investigated. We find that it is not beneficial to neurons synchronization if confining the coupling distance of random edges to a limit dmax but help to improve their coherence. Moreover, there is an optimal value of dmax at which the coherence is maximum. 相似文献
944.
Synchronization of a noise-perturbed generalized Lorenz system by
using sliding mode control method is investigated in this paper. Two
sliding mode control methods are proposed to synchronize the
noise-perturbed generalized Lorenz system. Numerical simulations are
also provided for the illustration and verification of the methods. 相似文献
945.
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949.
We present a generalized analytical solution to the normalized state equations of a class of coupled simple secondorder non-autonomous circuit systems. The analytical solutions thus obtained are used to study the synchronization dynamics of two different types of circuit systems, differing only by their constituting nonlinear element. The synchronization dynamics of the coupled systems is studied through two-parameter bifurcation diagrams, phase portraits, and time-series plots obtained from the explicit analytical solutions. Experimental figures are presented to substantiate the analytical results. The generalization of the analytical solution for other types of coupled simple chaotic systems is discussed. The synchronization dynamics of the coupled chaotic systems studied through two-parameter bifurcation diagrams obtained from the explicit analytical solutions is reported for the first time. 相似文献
950.
A fiber-based,multiple access timing signal synchronization scheme is demonstrated.By coupling out the bidirectional transmission signals,a highly stable timing signal can be recovered at arbitrary points along the fiber with the help of the loop delay message broadcasted via ethernet from the local module.The experiment is carried out on a 30-km fiber placed in a temperature-controlled box.In one-day period,when the round trip fiber transfer delay fluctuation is60 ns,the fluctuations of the stabilized timing signal from the download and the remote modules were only ±125 ps and±100 ps,respectively.Also,the system error caused by transmission path asymmetry and thermal drift is calibrated,and a100-ps magnitude synchronization accuracy is realized.This method could provide new insights into the construction of a fiber-based time transfer network. 相似文献