Ligang Cai

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A nonlinear redundant lifting wavelet packet algorithm was put forward in this study. For the node signals to be decomposed in different layers, predicting operators and updating operators with different orders of vanishing moments were chosen to take norm l(p) of the scale coefficient and wavelet coefficient acquired from decomposition, the predicting(More)
A least square method based on data fitting is proposed to construct a new lifting wavelet, together with the nonlinear idea and redundant algorithm, the adaptive redundant lifting transform based on fitting is firstly stated in this paper. By variable combination selections of basis function, sample number and dimension of basis function, a total of nine(More)
In order to develop reasonable modular product architecture with physically detachable modules, a new systematic method for product modularization is proposed based on axiomatic design (AD). In the proposed method, the product is decomposed hierarchically in its functional, physical and process domains according to AD. After the transformation from design(More)
—Based on the issue of torsional vibration, this article analyzes the structure of the drive part of coaxial drive printing system, constructs its mathematic model, and explores the mechanism of generation of torsional vibration of press-that is the coupling of inherent frequency between input signal and machine drive system which leads to torsional(More)
—Directing at the problem of torsional vibration occurred in the start-up procedures of long shaft drive transmission existed in printing equipment, we raised a variable structure control method based on Variable parameters fuzzy. The method not only displays feature of traditional non-linear variable structure control like non-deference derivation,(More)
The carrying capacity of hydrostatic turntable was influenced by the profile error. A direct method to solve the static equilibrium was proposed to obtain the axial motion error and the angular motion error components of the turntable based on the structural characteristic of the heavy duty CNC hydrostatic turntable and under the assumption that the(More)
This study theoretically analyzes the effect of surface roughness on the pressure distribution and load-carrying capacity of hydrostatic circular pads. The average pressure was expressed by establishing the volume flow rate of per unit width. In this study, we established two average Reynolds equations on radial direction and circumferential direction with(More)
An active tendon, consisting of a displacement actuator and a co-located force sensor, has been adopted by many studies to suppress the vibration of large space flexible structures. The damping, provided by the force feedback control algorithm in these studies, is small and can increase, especially for tendons with low axial stiffness. This study introduces(More)
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