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An automated and adaptive feature extraction method is discussed in this paper. The method is based on the wavelet packet transform (WPT) and used to extract features of electroencephalogram (EEG) signals for brain computer interfaces (BCIs). The idea is to employ the best basis algorithm to select the most appropriate wavelet and the best wavelet packet basis automatically. Meanwhile, both the selected...
This paper presents an image content authentication algorithm resilient to geometric and some general operations. The original image is normalized into a standard prototype form according to the blind normalization arithmetic, and then the smooth-component and the edge-character are drawn from the prototype image with the dyadic wavelet transform multi-scale edge detection. After coded with 64 bits,...
Symmetrical wavelet and anti-symmetrical wavelet have characteristics of linear phase and generalized linear phase respectively. They are very important to signal decomposition and reconstruction, because they can avoid signal distortion. Daubechies wavelets and Symlets wavelets have being used widely. Unfortunately, they aren't symmetrical. In this paper, firstly, general symmetrical wavelet construction...
Shape, as one of the intrinsic features of weapons and the other military equipments, becomes the most important key factor of object recognition upon the different techniques of image formation, and the researches on techniques of image retrieval using contour, the important shape feature, have been a focus of attention in the domain of image engineering. The paper proposes a hierarchical image retrieval...
The purpose of image fusion is to combine information from several different source images to one image, which becomes reliable and much easier to be comprehended by people. Based on analyzing the relations of average and standard deviation of the two or more source images, a new strategy to improve image fusion effect and a new evaluation measure named RAS (the ratio between average and standard...
This paper presents a novelty electromotor fault diagnosis method based on wavelet packets and BP neural network. Wavelet packets transform can decompose original signal into different spectrums, the corresponding energy eigenvector can be obtained, it expresses the energy characteristics of original signal; BP (back propagation) neural network is an effective tool to recognize fault types, neural...
It is one of main measures for safe operation of the fast reactor to use acoustic leak detecting technology to realize early detection for water/steam leak of steam generator in fast reactor nuclear power station. Based on experimental data about sodium loop experiment completed by Liquid Metal Laboratory of Tsinghua University, this paper investigates the application of wavelet noise elimination...
This paper proposes a kind of combination forecast model based on the wavelet analysis. First, the insurance income time series is decomposed under a multi-scale by using the Mallat algorithm. So the approximate (low frequency) component and the detail (high frequency) component under the corresponding scale are obtained. Then, the trend and cycle are distilled from the decomposition and modeled separately...
In this paper, a new image fusion method based on M-band wavelet is proposed. M-band wavelet transform domain has its superiority to 2-band wavelet transform domain in energy compaction and direction selection. Considering both the multi-scale-multi-direction information and the correlation property in M-band wavelet domain, an image fusion scheme based on cross-band-window is brought forward. The...
Approximate query processing has emerged as a cost-effective approach for dealing with the large database system. Recent work has demonstrated the effectiveness of the wavelet transform in reducing large amounts of data to compact set of wavelet coefficients. In this paper, we extend related works about approximate query processing using wavelet. Two algorithms about how to do union and difference...
In this study, we proposed a contextual filter edge detector and a multiscale edge tracker to extract edges for further analysis of computer vision. The contextual filter detected significant edges in the finest scale gradient image. Many noised or blurred cases were suppressed with higher decision levels. The edge tracker further improves the detected results using the multiscale gradient images...
A new hybrid approach to improving generalization of feedforward neural networks is presented. The hybrid approach combines several efficient methods, such as feature extraction via wavelet transform, construction of optimal networks architecture via fast cascade-correlation, dynamic optimization of learning parameters via simultaneous determination, avoiding overfitting problem via fast cross-validation...
A fast and automatic video object segmentation algorithm based on wavelet transform and moving edge detection is proposed in this paper. First, the wavelet transform is applied to two consecutive frames. The change detection method with different thresholds in four wavelet sub-bands and Canny edge detection are used in wavelet domain. After the inverse wavelet transform, the robust difference edge...
The region of interest (ROI) coding is an important application of region-based still image coding and can encode these significant regions with higher quality than others (background). In this paper, we present a new region-based image coding method called partial subbands maximum bitplanes shift (PSMBShift). The new method applies different scaling strategies for the different frequency subbands...
Experimental platform is used to simulate typical faults of turbine. Based on the frequency domain feature, energy eigenvector of frequency domain is presented in the wavelet packet analysis method, and the way of best tree is used to choose symptom. Finally, the fault states are recognized using neural network, and the simulations show that it makes a good performance with the method
The precision of cable fault location of traveling wave method is subjected to the uncertainty of the traveling wave speed. To solve this problem, the central distance theorem is presented after three new concepts of scaling time, scaling speed and central distance are defined based on wavelet analysis and multiresolution analysis. The relationship between the central distance, the scaling speed,...
This paper presents a new method for discussing persistence of financial risk based on volatility impulse response function. The new definition of volatility persistence and common persistence is established. Further more, the corresponding topics are introduced into the area of nonlinear common persistence through wavelet neural network. The proposed methods here are easy to be conducted, and can...
Distributed fiber optic sensing technique is considered as a promising tool to monitor continuously structural state in civil engineering. Distributed sensors produce large quantities of tempo-spatial data. The ability of wavelet transforms to detect abrupt changes, make them well suited for the analysis of monitoring data. This paper presents tempo-spatial wavelet-based data processing method for...
A method using DT-CWT spectral histograms and support vector machine (SVM) for face detection is proposed in this paper. In this face detection method, dual tree complex wavelets transform (DT-CWT) filter is used instead of Gabor filter. DT-CWT is a novel wavelet transform recently studied, which provides good directional selectivity in six different fixed orientations at different scales. It has...
In this paper, a systematic guideline is introduced to design a stable adaptive fuzzy wavelet controller with sliding mode for a class of uncertain nonlinear systems. Based on the Lyapunov synthesis approach, we construct the fuzzy wavelet controller such that it can basically control and guarantee the stability of the whole control system. On the other hand, a robust controller is designed to restrain...
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