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In order to meet the require of high speed and comfort and low producing cost, semi-active suspension for high-speed railway vehicle is adopted to control the vibration of car body. But accurate mathematic model of vehicle dynamics system is difficult to establish for the particularity of wheel-rail interaction and non-linear of system sky damper control needs the absolute speed of car body that its exact value is difficult to obtain. So adaptive fuzzy control method based on the acceleration feedback is put forward in the paper. The method which can modify automatically the scaling factor and control rules according to the acceleration and its change rate of car body is simulated by using ADAMS and MATLAB software. The simulation results show that the method can attenuate the vibration of car body and improve the comfort and stationarity effectively. [ABSTRACT FROM AUTHOR]

This paper presents a novel method for constructing non-separable wavelet filters. The high frequency sub-bands of non-separable wavelet transform can reveal more features than that of the common used separable wavelet transform. Then, we describe a blind watermarking scheme which is based on discrete non-separable wavelet transform (DNWT). More coefficients of DNWT can add watermark than that of discrete separable wavelet transform (DSWT). Experiment results show that the DNWT watermarking scheme is robust to noising, JPEG compression, and cropping. Especially, it is more resistant to sharpening than DSWT scheme. Furthermore, by adjusting the threshold such that the number of the DSWT coefficients to embed watermark is not less than the number of the DNWT coefficients, the performance of DSWT to sharpening is still worse than the DNWT. Such adjustment also dramatically decreases the robustness of the DSWT scheme to noising. [ABSTRACT FROM AUTHOR]