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Vibration signal of asynchronous motors are detected with multiple sensors and used to identifying multiple faults of motors in this paper. Independent components analysis method (ICA) is applied to compress measurements from several channels into a smaller amount of channel combinations and separate related vibration signal from interfering vibration sources, and support vector machine (SVM) based multi-class classifiers are used to identify multiple faults of asynchronous motors. Adventures of the proposed methods are that they are data-based and are not necessary to build an analytical model, and SVM-based identification can provide better performance with few datasets. Experiment results are provided to illustrate the performance of the detection and identification methods.

Transfer functions of power transformer can be used for detection and localization of partial discharges. There is no access to sectional windings when transformer insulation has been impregnated into oil, so the parameter identification of transformer windings is difficult without the knowledge of sectional winding voltages. In this paper, genetic algorithms (GAs) based approach are proposed to identify the parameters of transformer windings. An impulse signal was injected into the bushings of transformer, then the responses at neutral terminals were measured, and thee acquired data were used to identify the parameters using GAs. To accelerate GAs’ convergence, a zooming operator was introduced in genetic programming process. The experimental results show that the proposed ZGA approach is effective.

For solving signal restoration distortion affected by the signal spectrum composition changes and tested baseline drift, this papers methods mainly involve time-frequency energy analysis, wavelet soft threshold de-noising algorithm and baseline drift cancellation method. The result shows that these methods can effectively eliminate the interference of different micro-variable fault signals. The restored high-fidelity signals provide base for subsequent identification of fault reasons.

This paper proposes a cam curve synthesis method based on classical splines. The cam curve is described by the classical spline of order 6. Corresponding equations and boundary conditions are given to satisfy the specific requirements of the cam design problem. Then, a universal computation method is given and an example to illustrate the effectiveness of the proposed method is presented. It is shown that excellent design result can be gained easily, and the designer can adjust the interpolation values of the interior knots of the spline to change the cam curve in a local influence without any violation of the specific constraints.

Brushes-type blanket washer’s function is rubbing a high speed spinning brush roller against blanket roller, so as to clean the paper-lints and ink which adhere to the surface of blanket cylinder. It is very important to do a research into the dynamic structural analysis of the washer which determines the stability of this equipment. With the gyroscopic effect dynamic analysis of brush blanket, we get the relation curve between central offset of the washer and the load of permanent joint. The result show that a minute alteration of the central offset causes effect change of the load. This result provides a theoretical basis to control the effect change and then improve the stability and decrease the cost.

This paper proposes a method for the design of governor foot mechanism on high-speed printing press. According to the technological conditions, an optimal design model is presented to achieve the minimum deviation between the desired and actual track points. The physical dimensions of the linkages and the angular stroke of the driven cam can be gained by solving the presented optimum model.Then the driven cam's profile is calculated. The effectiveness of the proposed method is proved through an illustrative design example of a governor foot mechanism for high-speed operation.