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基于小波非线性自回归网络的水文预测模型 被引量:7
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作者 衣学军 魏守科 +4 位作者 石玉好 付常璐 邢昱臻 闫杰 赵金东 《计算机技术与发展》 2021年第3期70-77,共8页
不同时间尺度上的水文序列预测在水资源调配和防洪减灾决策中起着重要的作用。提出了一种基于小波分解和非线性自回归神经网络相结合的水文时间序列预测模型(WNARN)。运用Daubechies 5(db5)离散小波将水文序列数据分解为低频和高频子序... 不同时间尺度上的水文序列预测在水资源调配和防洪减灾决策中起着重要的作用。提出了一种基于小波分解和非线性自回归神经网络相结合的水文时间序列预测模型(WNARN)。运用Daubechies 5(db5)离散小波将水文序列数据分解为低频和高频子序列,作为非线性自回归神经网络模型(NARN)的输入变量,贝叶斯正则化优化算法用来泛化网络,训练模型对各子序列进行模拟预测,预测值经db5小波重构后得到原序列预测值。利用渭河流域三个水文站40多年的月径流量序列对所提出的WNARN模型进行验证和向前48步的预测能力测试,并与单一NARN模型的验证和预测结果进行对比。结果显示在相同的网络结构下所提出的方法能够显著提高水文序列的预测精度、预测周期及对重大水文事件的预测性,具有较高的泛化能力。 展开更多
关键词 水文预测 小波变换 daubechies 非线性自回归网络 贝叶斯正则化 渭河
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基于Daubechies小波变换在GPS信号处理中的应用 被引量:7
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作者 王英红 王冬霞 杨洪升 《辽宁工学院学报》 2004年第2期7-8,共2页
利用小波变换理论对带有噪声的GPS定位信号进行滤波,用多尺度分析特性对其信号进行轮廓和细节部分的逐步分解,将分解后的小波系数进行反变换可求出原始纯净信号。实验表明,Daubechies小波滤波器在对GPS信号滤波中达到满意效果。
关键词 daubechies 小波变换 GPS 信号处理 滤波 多尺度分析 全球定位系统
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CHARACTERIZATION OF MULTIPLIER SPACES WITH DAUBECHIES WAVELETS 被引量:2
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作者 杨奇祥 《Acta Mathematica Scientia》 SCIE CSCD 2012年第6期2315-2321,共7页
We characterize the multiplier spaces from Sobolev spaces to L2 with Daubechles wavelets without using capacity.
关键词 daubechies wavelet multiplier spaces Morrey spaces
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Non-classical Algorithm for Time Series Prediction of the Range of Economic Phenomena With Regard to the Interaction of Financial Market Indicators 被引量:2
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作者 Monika Hadas-Dyduch 《Chinese Business Review》 2014年第4期221-231,共11页
The aim of the article is to present non-clasical copyrighted algorithm for prediction of time series, presenting macroeconomic indicators and stock market indices. The algorithm is based on artificial neural networks... The aim of the article is to present non-clasical copyrighted algorithm for prediction of time series, presenting macroeconomic indicators and stock market indices. The algorithm is based on artificial neural networks and multi-resolution analysis (the algorithm is based on Daubechies wavelet). However, the main feature of the algorithm, which gives a good quality of the forecasts, is all included in the series analysis division into, a few partial under-series and prediction dependence on a number of other economic series. The algorithm used for the prediction, is copyrighted algorithm, labeled M.H-D in this article. Application of the algorithm was performed on a series presenting WIG 20. The forecast of WIG 20 was conditional on trading the Dow Jones, DAX, Nikkei, Hang Seng, taking into account the sliding time window. As an example application of copyrighted model, the forecast of WIG 20 for a period of two years, one year, six month was appointed. An empirical example is described. It shows that the proposed model can predict index with the scale of two years, one year, a half year and other intervals. Precision of prediction is satisfactory. An average absolute percentage error of each forecast was: 0.0099%---for two-year forecasts WIG 20; 0.0552%--for the annual forecast WIG 20; and 0.1788%---for the six-month forecasts WIG 20. 展开更多
关键词 macroeconomic indicators stock index forecasting WAVELET neural network wavelet transform daubechies wavelet
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A CHARACTERIZATION OF N-DIMENSIONAL DAUBECHIES TYPE TENSOR PRODUCT WAVELET 被引量:2
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作者 李登峰 彭思龙 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2001年第3期382-392,共11页
In this paper, we consider the problem of the existence of general non-separable variate orthonormal compactly supported wavelet basis when the symbol function has a special form. We prove that the general non-separab... In this paper, we consider the problem of the existence of general non-separable variate orthonormal compactly supported wavelet basis when the symbol function has a special form. We prove that the general non-separable variate orthonormal wavelet basis doesn't exist if the symbol function possesses a certain form. This helps us to explicate the difficulty of constructing the non-separable variate wavlet basis and to hint how to construct non-separable variate wavlet basis. 展开更多
关键词 daubechies type wavelet symbol function tensor product orthonormality
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Spectral Analysis and Validation of Parietal Signals for Different Arm Movements
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作者 Umashankar Ganesan A.Vimala Juliet R.Amala Jenith Joshi 《Intelligent Automation & Soft Computing》 SCIE 2023年第6期2849-2863,共15页
Brain signal analysis plays a significant role in attaining data related to motor activities.The parietal region of the brain plays a vital role in muscular movements.This approach aims to demonstrate a unique techniq... Brain signal analysis plays a significant role in attaining data related to motor activities.The parietal region of the brain plays a vital role in muscular movements.This approach aims to demonstrate a unique technique to identify an ideal region of the human brain that generates signals responsible for muscular movements;perform statistical analysis to provide an absolute characterization of the signal and validate the obtained results using a prototype arm.This can enhance the practical implementation of these frequency extractions for future neuro-prosthetic applications and the characterization of neurological diseases like Parkinson’s disease(PD).To play out this handling method,electroencepha-logram(EEG)signals are gained while the subject is performing different wrist and elbow movements.Then,the frontal brain signals and just the parietal signals are separated from the obtained EEG signal by utilizing a band pass filter.Then,feature extraction is carried out using Fast Fourier Transform(FFT).Subse-quently,the extraction process is done by Daubechies(db4)and Haar wavelet(db1)in MATLAB and classified using the Levenberg-Marquardt Algorithm.The results of the frequency changes that occurred during various wrist move-ments in the parietal region are compared with the frequency changes that occurred in frontal EEG signals.This proposed algorithm also uses the deep learn-ing pattern analysis network to evaluate the matching sequence for each action that takes place.Maximum accuracy of 97.2%and maximum error range of 0.6684%are achieved during the analysis.Results of this research confirm that the Levenberg-Marquardt algorithm,along with the newly developed deep learn-ing hybrid PatternNet,provides a more accurate range of frequency changes than any other classifier used in previous works of literature.Based on the analysis,the peak-to-peak value is used to define the threshold for the prototype arm,which performs all the intended degrees of freedom(DOF),verifying the results.These results would aid the speci 展开更多
关键词 Parietal EEG signals fast fourier transform Levenberg-Marquardt algorithm haar wavelet daubechies wavelet statistical analysis
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基于ARM的人脸识别系统的研究与实现 被引量:1
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作者 王仕民 叶继华 +2 位作者 黄亮 杨庆红 余敏 《东南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2010年第S1期244-248,共5页
使用人脸类Haar特征进行人脸检测,采用Daubechies小波去噪变换和PCA降维算法提取人脸特征,将经过PC机变换后的训练样本特征子空间文件通过网络传输到嵌入式平台,并结合最近邻算法识别人脸.实现了一种嵌入式人脸识别系统,解决了嵌入式人... 使用人脸类Haar特征进行人脸检测,采用Daubechies小波去噪变换和PCA降维算法提取人脸特征,将经过PC机变换后的训练样本特征子空间文件通过网络传输到嵌入式平台,并结合最近邻算法识别人脸.实现了一种嵌入式人脸识别系统,解决了嵌入式人脸识别系统由于图像处理数据巨大而造成处理效率低的难点.基于MagicARM2410开发板实现了该系统,结合实际图片进行了人脸识别测试,实践结果表明系统效果良好. 展开更多
关键词 嵌入式操作系统 人脸识别 HAAR daubechies PCA
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Noise Reduction in White Light Lidar Signal Using a One-Dim and Two-Dim Daubechies Wavelet Shrinkage Method
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作者 Toshihiro Somekawa Maria Cecilia D. Galvez +2 位作者 Masayuki Fujita Edgar A. Vallar Chihiro Yamanaka 《Advances in Remote Sensing》 2013年第1期10-15,共6页
A 1-D and 2-D Daubechies 5 (db5) discrete wavelet shrinkage methods using a 10 level decomposition was applied to white light lidar data particularly at 350 nm and 550 nm backscattered signal. At 350 nm, the backscatt... A 1-D and 2-D Daubechies 5 (db5) discrete wavelet shrinkage methods using a 10 level decomposition was applied to white light lidar data particularly at 350 nm and 550 nm backscattered signal. At 350 nm, the backscattered signal is very weak as compared to 550 nm backscattered signal because of the spectral intensity distribution of the generated white light. The 1-D and 2-D wavelet shrinkage method gave a much better result as compared with the moving average method. However, the 2-D wavelet shrinkage method produced a much better denoised lidar signal compared with the 1-D wavelet shrinkage method. This is indicated by the 142% increase in correlation coefficient between the 2-D denoised lidar signal and the 800 nm original lidar signal as compared with only 12% increase in correlation coefficient for the 1-D denoised lidar signal. The 2-D wavelet shrinkage method also gave a much higher SNR value of 65.9 compared to 1-D which is 38.8. 展开更多
关键词 WHITE Light LIDAR MULTI-WAVELENGTH WAVELET daubechies
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Continuity of a Class of Calderón-Zygmund Operators on Certain Besov Spaces
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作者 杨占英 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第4期530-534,共5页
In this paper, we introduce a class of non-convolution-type Calderón-Zygmund operators, whose kernels are certain sums involving the products of the Daubechies wavelets and their convolutions. And we obtain the c... In this paper, we introduce a class of non-convolution-type Calderón-Zygmund operators, whose kernels are certain sums involving the products of the Daubechies wavelets and their convolutions. And we obtain the continuity on the Besov spaces B 0,q p (1 ≤ p, q ≤∞), which is mainly dependent on the properties of the Daubechies wavelets and Lemari's T1 theorem for Besov spaces. 展开更多
关键词 Calderón-Zygmund operators Besov spaces daubechies wavelets
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Wavelet based detection of ventricular arrhythmias with neural network classifier
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作者 Sankara Subramanian Arumugam Gurusamy Gurusamy Selvakumar Gopalasamy 《Journal of Biomedical Science and Engineering》 2009年第6期439-444,共6页
This paper presents an algorithm based on the wavelet decomposition, for feature extraction from the Electrocardiogram (ECG) signal and recognition of three types of Ventricular Arrhythmias using neural networks. A se... This paper presents an algorithm based on the wavelet decomposition, for feature extraction from the Electrocardiogram (ECG) signal and recognition of three types of Ventricular Arrhythmias using neural networks. A set of Discrete Wavelet Transform (DWT) coefficients, which contain the maximum information about the arrhythmias, is selected from the wavelet decomposition. These coefficients are fed to the feed forward neural network which classifies the arrhythmias. The algorithm is applied on the ECG registrations from the MIT-BIH arrhythmia and malignant ventricular arrhythmia databases. We applied Daubechies 4 wavelet in our algorithm. The wavelet decomposition enabled us to perform the task efficiently and produced reliable results. 展开更多
关键词 daubechies 4 WAVELET ECG FEED FORWARD Neural Network VENTRICULAR ARRHYTHMIAS WAVELET De-composition
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A TVD Type Wavelet-Galerkin Method for Hamilton-Jacobi Equations
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作者 Ling-yan Tang Song-he Song 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2007年第2期303-310,共8页
In this paper, we use Daubechies scaling functions as test functions for the Galerkin method, and discuss Wavelet-Galerkin solutions for the Hamilton-Jacobi equations. It can be proved that the schemes are TVD schemes... In this paper, we use Daubechies scaling functions as test functions for the Galerkin method, and discuss Wavelet-Galerkin solutions for the Hamilton-Jacobi equations. It can be proved that the schemes are TVD schemes. Numerical tests indicate that the schemes are suitable for the Hamilton-Jacobi equations. Furthermore, they have high-order accuracy in smooth regions and good resolution of singularities. 展开更多
关键词 Hamilton-jacobi equation wavelet-galerkin method daubechies wavelet TVD method
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Selection of a Suitable Wavelet for Cognitive Memory Using Electroencephalograph Signal
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作者 S. Z. Mohd Tumari R. Sudirman A. H. Ahmad 《Engineering(科研)》 2013年第5期15-19,共5页
The aim of this study is to recognize the best and suitable wavelet family for analyzing cognitive memory using Electroencephalograph (EEG) signal. The participant was given some visual stimuli during the study phase,... The aim of this study is to recognize the best and suitable wavelet family for analyzing cognitive memory using Electroencephalograph (EEG) signal. The participant was given some visual stimuli during the study phase, which were a sequence of pictures that had to be remembered to acquire the EEG signal. The Neurofax EEG 9200 was used to record the acquisition of cognitive memory at channel Fz. The raw EEG signals were analyzed using Wavelet Transform. A lot of mother wavelets can be used for analyzing the signal, but do not lose any information on the wavelet, some predictions must be made beforehand. The criteria of the EEG signal were narrowed down to the Daubechies, Symlets and Coiflets, and it is the final selection depending on their Mean Square Error (MSE). The best solution would have the least difference between the original and constructed signal. Results indicated that the Daubechies wavelet at a level of decomposition of 4 (db4) was the most suitable wavelet for pre-processing the raw EEG signal of cognitive memory. To conclude, choosing the suitable wavelet family is more important than relying on the MSE value alone to successfully perform a wavelet transformation. 展开更多
关键词 EEG WAVELET Families MSE Visual Stimuli daubechies
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Two Very Accurate and Efficient Methods for Solving Time-Dependent Problems
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作者 Mohamed El-Gamel Waleed Adel M. S. El-Azab 《Applied Mathematics》 2018年第11期1270-1280,共11页
In this paper, collocation method based on Bernoulli and Galerkin method based on wavelet are proposed for solving nonhomogeneous heat and wave equations. The two methods have the linear systems solved by suitable sol... In this paper, collocation method based on Bernoulli and Galerkin method based on wavelet are proposed for solving nonhomogeneous heat and wave equations. The two methods have the linear systems solved by suitable solvers. Several examples are given to examine the performance of these methods and a comparison is made. 展开更多
关键词 WAVELET GALERKIN daubechies BERNOULLI COLLOCATION
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SEMG-based fighter pilot muscle fatigue analysis and operation performance research 被引量:1
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作者 Biyun Zhou Bo Chen +3 位作者 Huijuan Shi Lihao Xue Yingfang Ao Li Ding 《Medicine in Novel Technology and Devices》 2022年第4期345-349,共5页
Fatigue has a tremendously adverse impact on pilot performance.This study aims to explore the Biceps Brachii(BB),Rectus Femoris(RF),Flexor Carpi Radialis(FCR),and Tibialis Anterior(TA)activities of fighter pilots in t... Fatigue has a tremendously adverse impact on pilot performance.This study aims to explore the Biceps Brachii(BB),Rectus Femoris(RF),Flexor Carpi Radialis(FCR),and Tibialis Anterior(TA)activities of fighter pilots in the early and late combat stages,and the target hitting time.A total of 13 volunteers were recruited to conduct simulated combats inside a real fighter cockpit.The surface Electromyography(sEMG)was collected from all volunteers in the initial and final 20s of flight,and the target hitting time during three simulated combats was recorded.The root mean square(RMS)values of right BB and TA were significantly higher than the left side values(p<0.001),while insignificant differences were found in the RMS values between the bilateral RF and FCR.Compared to the early flight period,the median frequency(MF)values of BB and TA were significantly lower during the late flight period,and the RMS values were significantly higher(p<0.047).Contrastively,the RMS values of FCR and RF differed insignificantly during the late flight period.Regarding the target hitting time,a significant difference was noted between task 1 and rask3.Subjects exhibit varying levels of muscle fatigue for different muscle groups before and after the flight.The muscle fatigue levels are asymmetrical on the left and right sides.Muscle fatigue might reduce the pilots'operational ability.This study provides a reference for fighter pilot fatigue protection and treatment. 展开更多
关键词 Surface electromyography Flight fatigue Operation performance daubechies wavelet
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Using the Wavelet as the Private Key for Encrypting the Watermark
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作者 何小帆 《Journal of Chongqing University》 CAS 2002年第1期16-20,共5页
Watermarking is an effective approach to the copyright protection of digital media such as audio, image, and video. By inspiration from cryptography and considering the immensity of the set of all possible wavelets, i... Watermarking is an effective approach to the copyright protection of digital media such as audio, image, and video. By inspiration from cryptography and considering the immensity of the set of all possible wavelets, it is presented that in wavelet domain watermarking, the associated wavelet can be considered as the private key for encrypting the watermark so as to enhance the security of the embedded mark. This idea is partly supported by the fact that from computational complexity viewpoint, it is very time-consuming to search over the immense set of all candidate wavelets for the right one if no a priori knowledge is known about it. To verify our proposal, the standard image 'Lena' is first watermarked in a specific wavelet domain, the watermark recovery experiments are then conducted in the wavelet domain for a set of wavelets with the one used for mark embedded in it,separately. It follows from the experimental results that the mark can be recovered only in the right wavelet domain, which justifies the suggestion. 展开更多
关键词 Digital watermark WATERMARKING CRYPTOGRAPHY Private key cryptographic system WAVELET daubechies wavelet
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Daubechies小波变换在石材加工过程信号分析中的应用
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作者 何奕南 尤芳怡 《福建电脑》 2006年第12期7-8,共2页
采用热电偶夹丝法测量白刚玉砂轮磨削石材时接触弧区的温度,用Daubechies小波对温度信号进行消噪处理,在有效去除干扰噪声的同时较好地保留了信号中的有用成分。通过一维连续小波变换对信号进行分解,绘制小波分解的系数图,结果表明热电... 采用热电偶夹丝法测量白刚玉砂轮磨削石材时接触弧区的温度,用Daubechies小波对温度信号进行消噪处理,在有效去除干扰噪声的同时较好地保留了信号中的有用成分。通过一维连续小波变换对信号进行分解,绘制小波分解的系数图,结果表明热电偶被磨削的时间段内小波系数在不同尺度存在明显的自相似性,磨削弧区温度信号的自相似性是大量磨粒热冲击作用叠加的结果。 展开更多
关键词 daubechies 小波 磨削温度 石材
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SERIES REPRESENTATION OF DAUBECHIES' WAVELETS
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作者 X.G. Lu (Department of Applied Mathematics, Tsinghua University, Beijing, China) 《Journal of Computational Mathematics》 SCIE CSCD 1997年第1期81-96,共16页
This paper gives a kind of series represeotation of the scaling functions φNand the associated wavelets . constructed by Daubechies. Based on Poission sununation formula, the functions gh. φN(x+N-1), φN (x+N),'... This paper gives a kind of series represeotation of the scaling functions φNand the associated wavelets . constructed by Daubechies. Based on Poission sununation formula, the functions gh. φN(x+N-1), φN (x+N),'''' φN (x+2N-2)(Ox 1) are linearly represented by φN(x), φN(x + 1),''', φN(x + 2N - 2) and some polynomials of order less than N, and φ0(x):= (φN (x), φN (x + 1),''', φN (x + N -2))t is translated into a solution of a nonhomogeneous vectorvalued functional equationwhere A0, A1 are (N - 1) x (N - 1)-dimensional matrices, the components of P0(x), P1 (x) are polynomials of order less than N. By iteration, .φ0(x) is eventualy represented as an (N - 1)-dimensional vector series with vector norm where and 展开更多
关键词 PRO ER MATH Si WAVELETS SERIES REPRESENTATION OF daubechies
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基于图像内容过滤的智能防火墙系统研究与实现 被引量:22
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作者 许强 江早 赵宏 《计算机研究与发展》 EI CSCD 北大核心 2000年第4期458-464,共7页
针对目前网络安全系统对于图像信息处理能力不足的问题 ,开发了一种基于图像内容过滤的智能防火墙系统 ,能够准确、实时地监测网络中的图像信息 ,提高了网络系统的运行可靠性和安全性 .提出了一种基于轮廓特征抽取与多智能体技术的图像... 针对目前网络安全系统对于图像信息处理能力不足的问题 ,开发了一种基于图像内容过滤的智能防火墙系统 ,能够准确、实时地监测网络中的图像信息 ,提高了网络系统的运行可靠性和安全性 .提出了一种基于轮廓特征抽取与多智能体技术的图像内容检索算法作为本系统的核心算法 .该算法首次将图像检索问题看作是一个分布式求解问题 ,并以智能体技术作为支撑技术 ,解决了目前多维索引算法在大型图像库检索效率低下的问题 ,在不降低图像识别率的情况下 。 展开更多
关键词 智能防火墙系统 图像内容过滤 INTERNET网
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流体饱和多孔隙介质二维弹性波方程正演模拟的小波有限元法 被引量:27
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作者 张新明 刘克安 刘家琦 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2005年第5期1156-1166,共11页
本文将小波有限元法引入到流体饱和多孔隙介质二维波动方程的正演模拟中,以二维Daubechies小波的尺度函数代替多项式函数作为插值函数,构造二维张量积小波单元.引入一类特征函数解决了Daubechies小波没有显式解析表达式所带来的基函数... 本文将小波有限元法引入到流体饱和多孔隙介质二维波动方程的正演模拟中,以二维Daubechies小波的尺度函数代替多项式函数作为插值函数,构造二维张量积小波单元.引入一类特征函数解决了Daubechies小波没有显式解析表达式所带来的基函数积分值计算问题,并推导出计算分数节点上Daubechies小波函数值的递推公式,从而构造出由小波系数空间到波场位移空间的快速小波变换.数值模拟结果表明该方法是有效的. 展开更多
关键词 小波有限元法 流体饱和多孔隙介质 daubechies小波 尺度函数 快速小波变换
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Daubechies复小波的生成及其在短时电能质量扰动检测中的应用 被引量:26
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作者 刘守亮 肖先勇 《电工技术学报》 EI CSCD 北大核心 2005年第11期106-110,共5页
在分析比较了现有用于短时电能质量扰动检测的方法后,研究了用正交紧支复小波进行检测与抑制噪声的原理,提出用Daubechies正交紧支实小波派生其复小波的实用方法,并结合复小波变换提供的相位信息构造了多种新型复合信息形式。仿真表明,... 在分析比较了现有用于短时电能质量扰动检测的方法后,研究了用正交紧支复小波进行检测与抑制噪声的原理,提出用Daubechies正交紧支实小波派生其复小波的实用方法,并结合复小波变换提供的相位信息构造了多种新型复合信息形式。仿真表明,采用本文方法派生的复小波及其复合信息形式进行电能质量扰动检测,具有良好的噪声鲁棒性且提高了应用Mallat算法的实时性。 展开更多
关键词 电能质量 短时扰动 daubechies复小波 检测 噪声鲁棒性 实时性
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