To cope with the problem of frequency aliasing in mallat algorithm, which makes traditional discrete wavelet transform (DWT) inappropriate for feature extraction in some cases, an improved algorithm composed of sub-ba...
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To cope with the problem of frequency aliasing in mallat algorithm, which makes traditional discrete wavelet transform (DWT) inappropriate for feature extraction in some cases, an improved algorithm composed of sub-band reconstruction and Fourier transform is suggested through which the original signal could be split into a series of sub-bands of different frequencies with little distortion both in time and frequency domains. This strategy is developed to extract local features from analytical signals accurately as well as straightforwardly. Some NIR spectra have been selected as examples to demonstrate the availability and application of the proposed method.
An algorithm based on Biorthogonal Spline Wavelet is developed for detecting ECG characters points. In the algorithm, the Biorthogonal Spline Wavelet Transform of the ECG signal is first calculated using mallat Algori...
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ISBN:
(纸本)9781424464968
An algorithm based on Biorthogonal Spline Wavelet is developed for detecting ECG characters points. In the algorithm, the Biorthogonal Spline Wavelet Transform of the ECG signal is first calculated using mallat algorithm. And then the R-peak is located by finding the best modulus maximum pair of the wavelet transform in the scale of 2(3). A more robust method to find the modulus maximum pair is put forward in this paper. The methods finding the onsets and offsets of QRS complexes, P and T waves are also provided. The detection rate of QRS complexes for the algorithm is above 99.7% for MIT/BIH database and the processing time is considerably little.
The application of Wavelet-based still image compression is becoming more and more perfect as the wavelet theory research proceeds in latest *** on the analysis of the basic theory of wavelet transform, the applicatio...
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ISBN:
(纸本)9781424458219;9781424458240
The application of Wavelet-based still image compression is becoming more and more perfect as the wavelet theory research proceeds in latest *** on the analysis of the basic theory of wavelet transform, the application of wavelet transform is studied in still image compression, and implement the Daubechies 9/7 wavelet transform of three decomposition by using the VC++ platform *** experimental results are given in the corresponding part of the reconstructed image and compression ratio and PSNR values.
This paper takes financial data as one-dimensional random signal and uses wavelet mallat algorithm to denoise the original signal in order to get a more accurate signal which fits market situation *** the empirical an...
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This paper takes financial data as one-dimensional random signal and uses wavelet mallat algorithm to denoise the original signal in order to get a more accurate signal which fits market situation *** the empirical analysis,this paper applies closing price of Baoshan Iron and Steel shares for example to verify the capacity of wavelet multi-resolution analysis on financial data processing,and the result is satisfactory.
Support Vector Machines (SVM) is a new type of machine learning algorithm. Compared with conventional learning algorithms, SVM enhances the generalization ability of the models by employing structural risk minimizatio...
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ISBN:
(纸本)0769525288
Support Vector Machines (SVM) is a new type of machine learning algorithm. Compared with conventional learning algorithms, SVM enhances the generalization ability of the models by employing structural risk minimization criterion to minimize the sample errors and simultaneously decrease the upper bound of the predict error of the models. The global optimal solution can be uniquely obtained owing to that SVM converts machine learning into quadratic programming. Based on the local data from hydrogenation equipment, a predictive model using Least Squares Support Vector Machines (LS-SVM) is established for three important quality targets of diesel oil in this paper, and compared with neural network and stands SVM on precision. Finally, it is proved that the proposed predictive models based on LS-SVM can predict the quality target more efficiently and rapidly than stands SVM and neural network. It provided a method for online diagnosing fault of quality targets.
Wheel speed is a critical parameter in vehicle roadway test. However, because of the internal defects of the wheel speed sensor structure and some electromagnetic inference, this signal is inevitably influenced by kin...
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ISBN:
(纸本)9780769535838
Wheel speed is a critical parameter in vehicle roadway test. However, because of the internal defects of the wheel speed sensor structure and some electromagnetic inference, this signal is inevitably influenced by kinds of awful noises during the measurement process. These wide band stochastic noises badly influence the analysis of vehicle performance. It is difficult to eliminate these noises with traditional way based on Fourier transform. Wavelet transform is an analytical method of time-frequency, which is especially suitable for the analysis of non-stable signals. This method contains a characteristic of multi-resolution analysis as well as the ability of identifying partial characteristics of signals in time-frequency domain. According to different characteristics of signals and noises at every scale spaces after wavelet transform, the method of soft-threshold is applied to eliminate the noises in this paper. The result suggests this method is effective in wheel speed signal denoising.
While in the process of decomposition of the mallat discrete wavelet transform (DWT) fast algorithm, the algorithm has a drawback, that is, there is frequency distortion in the high frequency subband. In this paper, a...
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While in the process of decomposition of the mallat discrete wavelet transform (DWT) fast algorithm, the algorithm has a drawback, that is, there is frequency distortion in the high frequency subband. In this paper, a new algorithm of decomposition and reconstruction in the discrete wavelet is presented. The algorithm can solve the frequency distortion in the high frequency subband in the process of decimation in each level. The simulation of numerical value example tests the validity of the algorithm.
Synthetic aperture sonar (SAS) is actively used in sea bed imagery. Indeed high resolution images provided by SAS are of great interest, especially for the detection, localization and eventually classification of obje...
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Synthetic aperture sonar (SAS) is actively used in sea bed imagery. Indeed high resolution images provided by SAS are of great interest, especially for the detection, localization and eventually classification of objects lying on sea bed. SAS images are highly corrupted by a granular multiplicative noise, called speckle noise which reduces spatial and radiometric resolutions. The purpose of this article is to present a new adaptive processing that allows image filtering, for both the additive and multiplicative noise case. This new process is based on the marriage between a multi-resolution transformation and a filtering method. The filtering technique used here is based on the two-dimensional stochastic matched filtering method, which maximizes the signal-to-noise ratio after processing and minimizes mean square error between the signal's approximation and the original one. Results obtained on real SAS data are presented and compared with those obtained using classical processing. (c) 2006 Elsevier B.V. All rights reserved.
In this paper based on 3d wavelet moments we present a new method called fractal scale descriptors for 3d objects. Just like wavelet moments, they are still robust to translation, rotation and scale, and have the mult...
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ISBN:
(纸本)9781424410651
In this paper based on 3d wavelet moments we present a new method called fractal scale descriptors for 3d objects. Just like wavelet moments, they are still robust to translation, rotation and scale, and have the multi-resolution features in the radial direction, which can handle noise to some extent and provide multi-level features to satisfy, various requirements. Furthermore the new method is prior to the original 3d wavelet moments in computational complexity by using the fast algorithm of the spherical harmonics together with the mallat algorithm of the wavelets.
While in the process of decomposition of the mallat discrete wavelet transform(DWT) fast algoritm, the algorithm have a drawback, that is, there is frequency distortion in the high frequency subband In this paper, a n...
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ISBN:
(纸本)9781424410651
While in the process of decomposition of the mallat discrete wavelet transform(DWT) fast algoritm, the algorithm have a drawback, that is, there is frequency distortion in the high frequency subband In this paper, a new discrete wavelet decomposition and reconstruction algorithm is presented The algorithm can solve the frequency distortion in the high frequency subband in the process of decimation in each level. The simulation of numerical value example had verified the validity of the algorithm.
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