Li Hua

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—Vector wavelet transforms for vector-valued fields can be implemented directly from multiwavelets; however, existing multiwavelets offer surprisingly poor performance for transforms in vector-valued signal-processing applications. In this paper, the reason for this performance failure is identified, and a remedy is proposed. A multiwavelet design(More)
Spread-spectrum watermarking, in which random noise is added to transform coefficients and detected with a correlation operator, has become a preferred paradigm for many watermarking applications. This paper analyzes the performance of such a watermark-ing system when the underlying transform is a tight frame rather than a traditional orthonormal expansion.(More)
Vector wavelet transforms for vector-valued fields can be implemented directly from multiwavelets; however, existing multiwavelets offer surprisingly poor performance for transforms in vector-valued signal-processing applications. In this paper, the reason for this performance failure is identified, and a remedy is proposed. A multiwavelet design criterion,(More)
Skid steering of 4-wheel-drive electric vehicles has good maneuverability and mobility as a result of the application of differential torque to wheels on opposite sides. For path following, the paper utilizes the techniques of sliding mode control based on extended state observer which not only has robustness against the system dynamics not modeled and(More)
Aiming at the problem that traditional experiment method and means are very difficult to satisfy the requirement of experiment teaching for complex and cunning breechblock due to the hardware rest riction, experiment time and student number, virtual technology is applied in teaching to supply good learning environment of openness, euroky and interactivity(More)
—Geoscience applications often produce sizable datasets which are vector-valued and increasingly in need of compression algorithms to reduce storage and transmission burdens, particularly when the data is time-varying. In this paper, several advanced interframe-compression techniques are extended from the traditional realm of natural video to the coding of(More)