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Copyright of Chinese Medical Equipment Journal is the property of Chinese Medical Equipment Journal Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Medical Equipment Journal is the property of Chinese Medical Equipment Journal Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aiming at the non-stationary and nonlinearity characteristics of reciprocating compressor vibration signal,a fault diagnosis method for bearing fault of reciprocating compressor based on LMD multiscale entropy and SVM is proposed.To improve the envelope approximation accuracy of local mean and envelope estimation,cubic Hermite interpolation method is used to construct envelope curves between extreme points according to the excellent characteristic of shape preservation.The vibration signals in each state are decomposed into a series of PF components with the improved LMD method,and the PF components which contain the main information of fault state are chosen according to the relative coefficient.By using the multiscale entropy,the quantitative description of the PF components is carried out,and the optimized scale factor is selected based on the maximum of average distances between different states,so the eigenvectors which have the best divisibility are extracted.The SVM is taken as pattern classifier,the type of bearing clearance fault is diagnosed,and the superiority of this method is verified by comparing the eigenvectors extracted by LMD and sample entropy and LMD and approximate entropy method.

This paper used the multiscale entropy analysis method to analyze the relationship. It quantitatively analyzed the network traffic complexities of the classical routing protocol AODV and the routing protocols AODV-FABL and AODV-CM, which were improved from AODV, at different time scales. Analysis results confirm that the network traffic complexity of those routing protocols are all higher and have large fluctuation in smaller time scales, and are all lower and shows the long-range dependence in larger time scales. This paper also pointed and analyzed the relationship between the network traffic complexity of those routing protocols and the changing speed of network topology. [ABSTRACT FROM AUTHOR]