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The Biorthogonality of Multiple Vector-valued Bivariate Wavelet Packets
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作者 CHEN Shao-dong HUANG Na 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第2期208-213,共6页
The notion of a sort of biorthogonal multiple vector-valued bivariate wavelet packets,which are associated with a quantity dilation matrix,is introduced.The biorthogonality property of the multiple vector-valued wavel... The notion of a sort of biorthogonal multiple vector-valued bivariate wavelet packets,which are associated with a quantity dilation matrix,is introduced.The biorthogonality property of the multiple vector-valued wavelet packets in higher dimensions is studied by means of Fourier transform and integral transform biorthogonality formulas concerning these wavelet packets are obtained. 展开更多
关键词 BIVARIATE multiple vector-valued multiresolution analysis multiple vectorvalued scaling function multiple vector-valued wavelet packets biorthogonality
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Construction of Orthogonal Vector-valued Wavelets and Characteristics of Vector-valued Wavelet Packets 被引量:1
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作者 CHEN Qing-jiang LIU Hong-yun 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第3期360-367,共8页
The notion of vector-valued multiresolution analysis is introduced and the concept of orthogonal vector-valued wavelets with 3-scale is proposed. A necessary and sufficient condition on the existence of orthogonal vec... The notion of vector-valued multiresolution analysis is introduced and the concept of orthogonal vector-valued wavelets with 3-scale is proposed. A necessary and sufficient condition on the existence of orthogonal vector-valued wavelets is given by means of paraunitary vector filter bank theory. An algorithm for constructing a class of compactly supported orthogonal vector-valued wavelets is presented. Their characteristics is discussed by virtue of operator theory, time-frequency method. Moreover, it is shown how to design various orthonormal bases of space L^2(R, C^n) from these wavelet packets. 展开更多
关键词 ORTHOGONAL Hermitian matrix vector-valued multiresolution analysis vector-valued scaling functions vector-valued wavelets vector-valued wavelet packets
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Multiple Time Scale Analysis of River Runoff Using Wavelet Transform for Dagujia River Basin, Yantai, China 被引量:10
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作者 LIU Delin LILT Xianzhao +2 位作者 LI Bicheng ZHAO Shiwei LI Xiguo 《Chinese Geographical Science》 SCIE CSCD 2009年第2期158-167,共10页
Based on monthly river runoff and meteorological data, a method of Morlet wavelet transform was used to analyze the multiple time scale characteristics of river runoff in the Dagujia River Basin, Yantai City, Shandong... Based on monthly river runoff and meteorological data, a method of Morlet wavelet transform was used to analyze the multiple time scale characteristics of river runoff in the Dagujia River Basin, Yantai City, Shandong Province. The results showed that the total annual river runoffin the Dagujia River Basin decreased significantly from 1966 to 2004, and the rate of decrease was 48× 10^6ma/10yr, which was higher than the mean value of most rivers in China. Multiple time scale characteristics existed, which accounted for different aspects of the changes in annual river runoff, and the major periods of the runofftime series were identified as about 28 years, 14 years and 4 years with decreasing levels of fluctuation. The river runoff evolution process was controlled by changes in precipitation to a certain extent, but it was also greatly influenced by human activities. Also, for different time periods and scales, the impacts of climate changes and human activities on annual river runoff evolution occurred at the same time. Changes in the annual river runoffwere mainly associated with climate change before the 1980s and with human activities after 1981. 展开更多
关键词 multiple time scale river runoff climate change Morlet wavelet transform Dagujia River
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Multiple description scalable video coding based on 3D lifted wavelet transform 被引量:3
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作者 KIM Yong-deak 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第5期857-863,共7页
In this work, a new method to deal with the unconnected pixels in motion compensated temporal filtering (MCTF) is presented, which is designed to improve the performance of 3D lifted wavelet coding. Furthermore, multi... In this work, a new method to deal with the unconnected pixels in motion compensated temporal filtering (MCTF) is presented, which is designed to improve the performance of 3D lifted wavelet coding. Furthermore, multiple description scalable coding (MDSC) is investigated, and novel MDSC schemes based on 3D wavelet coding are proposed, using the lifting imple- mentation of temporal filtering. The proposed MDSC schemes can avoid the mismatch problem in multiple description video coding, and have high scalability and robustness of video transmission. Experimental results showed that the proposed schemes are feasible and adequately effective. 展开更多
关键词 multiple DESCRIPTION SCALABLE coding (MDSC) MOTION compensated temporal filtering (MCTF) Block-split bidi-rectional MOTION estimation 3D lifted wavelet transform
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Characterizations of Orthogonal Vector-valued Multivariate Wavelet Packets
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作者 HUA De-lin FENG Jin-shun 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第4期606-614,共9页
In this paper, the notion of orthogonal vector-valued wavelet packets of space L2 (R^s, C^n) is introduced. A procedure for constructing the orthogonal vector-valued wavelet packets is presented. Their properties ar... In this paper, the notion of orthogonal vector-valued wavelet packets of space L2 (R^s, C^n) is introduced. A procedure for constructing the orthogonal vector-valued wavelet packets is presented. Their properties are characterized by virtue of time-frequency analysis method, matrix theory and finite group theory, and three orthogonality formulas are obtained. Finally, new orthonormal bases of space L2(R^s,C^n) are extracted from these wavelet packets. 展开更多
关键词 ORTHOGONALITY refinement equation vector-valued multiresolution analysis vector-valued scaling function vector-valued wavelet packets
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Triadic Synchrony: Application of Multiple Wavelet Coherence to a Small Group Conversation
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作者 Ken Fujiwara 《Applied Mathematics》 2016年第14期1477-1483,共7页
By applying multiple wavelet coherence (MWC) to data from human body movements in triadic interaction, this study quantified triadic synchrony, rhythmic similarity among three interactants. Thirty-nine Japanese underg... By applying multiple wavelet coherence (MWC) to data from human body movements in triadic interaction, this study quantified triadic synchrony, rhythmic similarity among three interactants. Thirty-nine Japanese undergraduates were randomly assigned in a triad, and engaged in a brain-storming task. Triadic synchrony was quantified by calculating MWC to the time-series movement data collected by Kinect v2 sensor. The existence of synchrony was statistically tested by using a pseudo-synchrony paradigm. Results showed that the averaged value of MWC was higher in the experimental participant trio than in those of the pseudo trio in the frequency band of 0.5 - 1 Hz. The result supports the possible utility of applying multiple wavelet coherence to evaluate triadic synchrony in a small group interaction. 展开更多
关键词 multiple wavelet Coherence Nonverbal Behavior Synchrony Small Group Automated Method
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Multiple descriptions based wavelet image coding
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作者 陈海林 杨宇航 《Journal of Zhejiang University Science》 EI CSCD 2004年第1期55-61,共7页
We present a simple and efficient scheme that combines multiple descriptions coding with wavelet transform under JPEG2000 image coding architecture. To reduce packet losses, controlled amounts of redundancy are added ... We present a simple and efficient scheme that combines multiple descriptions coding with wavelet transform under JPEG2000 image coding architecture. To reduce packet losses, controlled amounts of redundancy are added to the wavelet transform coefficients to produce multiple descriptions of wavelet coefficients during the compression process to produce multiple descriptions bit-stream of a compressed image. Even if areceiver gets only parts of descriptions (other descriptions being lost), it can still reconstruct image with acceptable quality. Specifically, the scheme uses not only high-performance wavelet transform to improve compression efficiency, but also multiple descriptions technique to enhance the robustness of the compressed image that is transmitted through unreliable network channels. 展开更多
关键词 multiple descriptions Discrete wavelet transform (DWT) JPEG2000
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Multiple Time-scale Characteristics of Runoff Variations in Middle Reaches of Huolin River and Their Effects 被引量:3
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作者 LU Xiaoning DENG Wei ZHANG Shuqing 《Chinese Geographical Science》 SCIE CSCD 2007年第2期143-150,共8页
The Huolin River is one of the most important water sources for Xianghai wetland, Horqin wetland, and Chaganhu wetland in the western Songnen Plain of Northeast China. The annual runoff series of 46 years at Baiyunhus... The Huolin River is one of the most important water sources for Xianghai wetland, Horqin wetland, and Chaganhu wetland in the western Songnen Plain of Northeast China. The annual runoff series of 46 years at Baiyunhushuo Hydrologic Station, which is located in the middle reaches of the Huolin River, were analyzed by using wavelet analysis. Main objective was to discuss the periodic characteristics of the runoff, and examine the temporal patterns of the Huolin River recharging to the floodplain wetlands in the lower reaches of the river, and the corresponding effects of recharging variation on the environmental evolution of the wetlands. The results show that the annual runoff varied mainly at three time scales. The intensities of periodical signals at different time scales were strongly characterized by local distribution in its time frequency domain. The interdecadal variation at a scale of more than 30yr played a leading role in the temporal pattern ofrnnoffvariation, and at this scale, the runoffat Baiyunhushuo Hydrologic Station varied in turn of flood, draught and flood. Accordingly, the landscape of the floodplain wetlands presented periodic features, especially prominent before the 1990s. Compared with intense human activities, the runoff periodic pattern at middle (10-20yr) and small (1-10yr) scales, which has relatively low energy, exerted unobvious effects on the environmental evolution of the floodplain wetlands, especially after the 1990s. 展开更多
关键词 floodplain wetland RUNOFF multiple time-scale wavelet analysis Huolin River
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Synergistic effects of multiple driving factors on the runoff variations in the Yellow River Basin,China 被引量:4
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作者 WANG Junjie SHI Bing +2 位作者 ZHAO Enjin CHEN Xuguang YANG Shaopeng 《Journal of Arid Land》 SCIE CSCD 2021年第8期835-857,共23页
River runoff plays an important role in watershed ecosystems and human survival,and it is controlled by multiple environmental factors.However,the synergistic effects of various large-scale circulation factors and met... River runoff plays an important role in watershed ecosystems and human survival,and it is controlled by multiple environmental factors.However,the synergistic effects of various large-scale circulation factors and meteorological factors on the runoff on different time-frequency scales have rarely been explored.In light of this,the underlying mechanism of the synergistic effects of the different environmental factors on the runoff variations was investigated in the Yellow River Basin of China during the period 1950-2019 using the bivariate wavelet coherence(WTC)and multiple wavelet coherence(MWC)methods.First,the continuous wavelet transform(CWT)method was used to analyze the multiscale characteristics of the runoff.The results of the CWT indicate that the runoff exhibited significant continuous or discontinuous annual and semiannual oscillations during the study period.Scattered inter-annual time scales were also observed for the runoff in the Yellow River Basin.The meteorological factors better explained the runoff variations on seasonal and annual time scales.The average wavelet coherence(AWC)and the percent area of the significant coherence(PASC)between the runoff and individual meteorological factors were 0.454 and 19.89%,respectively.The circulation factors mainly regulated the runoff on the inter-annual and decadal time scales with more complicated phase relationships due to their indirect effects on the runoff.The AWC and PASC between the runoff and individual circulation factors were 0.359 and 7.31%,respectively.The MWC analysis revealed that the synergistic effects of multiple factors should be taken into consideration to explain the multiscale characteristic variations of the runoff.The AWC or MWC ranges were 0.320-0.560,0.617-0.755,and 0.819-0.884 for the combinations of one,two,and three circulation and meteorological factors,respectively.The PASC ranges were 3.53%-33.77%,12.93%-36.90%,and 20.67%-39.34%for the combinations one,two,and three driving factors,respectively.The combinations of precipitation,evapotranspiration(or the number of rainy days),and the Arctic Oscillation performed well in explaining the variability in the runoff on all time scales,and the average MWC and PASC were 0.847 and 28.79%,respectively.These findings are of great significance for improving our understanding of hydro-climate interactions and water resources prediction in the Yellow River Basin. 展开更多
关键词 synergistic effects PRECIPITATION runoff variations atmospheric circulations multiple wavelet coherence Yellow River Basin
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Orthogonal Multiple Vector-Valued Wavelet Packets 被引量:3
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作者 陈清江 程正兴 李学志 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2007年第2期289-297,共9页
The multiple vector-valued wavelet packets are defined and investigated. A procedure for constructing the multiple vector-valued wavelet packets is presented. The properties of multiple vector-valued wavelet packets a... The multiple vector-valued wavelet packets are defined and investigated. A procedure for constructing the multiple vector-valued wavelet packets is presented. The properties of multiple vector-valued wavelet packets are discussed by using integral transformation and operator theory. Finally, new orthogonal bases of L^2(R, C^s×s) is constructed from the orthogonal multiple vector-valued wavelet packets. 展开更多
关键词 vector-valued multiresolution analysis multiple vector-valued scaling functions multiple vector-valued wavelet packets refinement equation.
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Multiple Image Watermarking with Discrete Cosine Transform 被引量:1
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作者 Mahbuba Begum Mohammad Shorif Uddin 《Journal of Computer and Communications》 2021年第3期88-94,共7页
Multiple image watermarking is an advanced concept of singular watermarking techniques. The existing singular digital image watermarking techniques cannot obtain all the design goals, such as imperceptibility, robustn... Multiple image watermarking is an advanced concept of singular watermarking techniques. The existing singular digital image watermarking techniques cannot obtain all the design goals, such as imperceptibility, robustness, security, and capacity simultaneously with perfection. Hence, the multiple image watermarking technique is designed that embeds several watermarks into the same host image for conveying multiple information. This paper proposed a multiple image watermarking technique with Discrete Cosine Transform (DCT) for ensuring the low computational time for embedding, encryption, decryption as well as extraction of the watermark images. Here, DCT is used to ensure the visual quality of the host image, and a random binary matrix is used to improve the security of the digital image. We have given a basic framework for multiple image watermarking. Our experimental results show satisfactory performance. 展开更多
关键词 multiple Watermarking Discrete Cosine Transform Discrete wavelet Transform Arnold Transform
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MULTIPLE TIME SCALE ANALYSIS OF CLIMATE VARIATION IN Macao DURING THE LAST 100 YEARS
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作者 冯瑞权 吴池胜 +5 位作者 王婷 何夏江 王安宇 刘吉 梁必骐 梁嘉静 《Journal of Tropical Meteorology》 SCIE 2012年第1期21-31,共11页
The multiple time scale climate changes are studied and calculated with statistical analysis and wavelet transformation on the basis of daily series of observed data over the period 1901-2007 in Macao.The result shows... The multiple time scale climate changes are studied and calculated with statistical analysis and wavelet transformation on the basis of daily series of observed data over the period 1901-2007 in Macao.The result shows that statistically significant oscillations with 2 to 5 years of period generally exist in the series of climate variables(e.g.annual mean surface air temperature and precipitation as well as evaporation etc.),but with obvious locality in time domain.The variation of annual mean surface air temperature has a quasi 60-year period.The phases of the 60-year variation approximately and consistently match that of Atlantic Multidecadal Oscillation(AMO).The oscillations of seasonal mean surface air temperature in summer and winter have the periods of quasi 30-year and quasi 60-year,respectively.These two periods of oscillations have statistically significant correlation with Pacific decadal oscillation(PDO) and AMO,individually.The multidecadal variations of the precipitation of the annually first flood period and annual evaporation are dominated by periods of quasi 30-year and quasi 50-year,respectively. 展开更多
关键词 climate change in Macao wavelet transformation multiple time scales
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A multiple watermarks algorithm for image content authentication
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作者 蔡立军 李睿 易叶青 《Journal of Central South University》 SCIE EI CAS 2012年第10期2866-2874,共9页
A novel multiple watermarks cooperative authentication algorithm was presented for image contents authentication.This algorithm is able to extract multiple features from the image wavelet domain,which is based on that... A novel multiple watermarks cooperative authentication algorithm was presented for image contents authentication.This algorithm is able to extract multiple features from the image wavelet domain,which is based on that the t watermarks are generated.Moreover,a new watermark embedding method,using the space geometric model,was proposed,in order to effectively tackle with the mutual influences problem among t watermarks.Specifically,the incidental tampering location,the classification of intentional content tampering and the incidental modification can be achieved via mutual cooperation of the t watermarks.Both the theoretical analysis and simulations results validate the feasibility and efficacy of the proposed algorithm. 展开更多
关键词 multiple watermarks cooperation authentication wavelet transform image wavelet domain intentional contenttampering incidental modification
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多尺度小波联合空域估计的FMCW雷达呼吸心率检测
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作者 韦琳 熊浩 +1 位作者 祝太虎 张正文 《昆明理工大学学报(自然科学版)》 北大核心 2025年第5期69-79,共11页
FMCW(Frequency Modulated Continuous Wave)雷达呼吸心率检测具有便携、无感等特点,但在检测过程中存在空间杂波,易使呼吸心跳信号分离失真;呼吸信号的高次谐波处于心跳信号的低频带附近,也严重影响心率检测.针对以上问题,提出一种多... FMCW(Frequency Modulated Continuous Wave)雷达呼吸心率检测具有便携、无感等特点,但在检测过程中存在空间杂波,易使呼吸心跳信号分离失真;呼吸信号的高次谐波处于心跳信号的低频带附近,也严重影响心率检测.针对以上问题,提出一种多尺度小波联合空域估计的FMCW雷达呼吸心率检测方法.首先,采用单轮集成经验模态分解(SEEMD)算法将中频信号分解为多个尺度信号;其次,再通过离散小波变换(DWT)从最优尺度信号中分离呼吸信号和心跳信号;最后,采用多重信号分类(MUSIC)算法将呼吸信号和心跳信号转化到空域中以消除呼吸谐波的影响,准确估计呼吸率和心率.实验结果表明,所提方法下的呼吸率检测准确率达到94.62%,心率检测准确率达到97.81%.与传统算法相比,本文方法具有更高的检测准确率和鲁棒性,适用于强干扰环境. 展开更多
关键词 FMCW雷达 单轮集成经验模态分解 离散小波变换 多重信号分类
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抚仙湖流域多年气象水文演变规律及趋势研究 被引量:1
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作者 朱文祥 《水利建设与管理》 2025年第6期69-76,81,共9页
为探寻抚仙湖水文气象演变和成因特点,本文基于流域1965—2023年年尺度水文气象资料,采用线性倾向估计法、Hurst指数法、小波分析法和多元回归分析法等探讨得到:1965年以来,抚仙湖流域降水量、蒸发量和水资源量均呈显著减少趋势,年均气... 为探寻抚仙湖水文气象演变和成因特点,本文基于流域1965—2023年年尺度水文气象资料,采用线性倾向估计法、Hurst指数法、小波分析法和多元回归分析法等探讨得到:1965年以来,抚仙湖流域降水量、蒸发量和水资源量均呈显著减少趋势,年均气温显著升高;流域内气温、降水量、蒸发量和水资源量的Hurst指数依次为0.72、0.69、0.69和0.79,变化过程均发生了突变且存在中等强度的变化趋势持续性。抚仙湖流域气温、降水量和蒸发量存在35年的小波变化主周期,流域水资源量存在25年的小波变化主周期。降水和气温对水资源影响显著,各气象要素大致能分别解释抚仙湖流域长系列(1965—2023年)、前期系列(1965—2008年)和近期系列(2009—2023年)约83.2%、82.0%和88.9%的水资源变异。未来流域内气温的持续升高、降水量和水资源量的持续减少还将使抚仙湖水位呈波动下降态势,抚仙湖水资源保护形势仍不容乐观。 展开更多
关键词 气象水文 演变规律 小波分析 多元回归 水资源 抚仙湖水位
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乘法组合赋权的小波去噪复合评价方法
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作者 唐盛华 蔡东亨 +1 位作者 张学兵 蒋嘉明 《湘潭大学学报(自然科学版)》 2025年第2期168-179,共12页
针对传统质量评价指标在纯净值未知情况下不能满足小波去噪质量评价的问题,提出了一种复合评价指标,为小波去噪参数的选择提供有效评价.该指标采用曲率平滑度与均方根误差作为分量,用熵权法与变异系数法将分量的归一化值进行定权,然后... 针对传统质量评价指标在纯净值未知情况下不能满足小波去噪质量评价的问题,提出了一种复合评价指标,为小波去噪参数的选择提供有效评价.该指标采用曲率平滑度与均方根误差作为分量,用熵权法与变异系数法将分量的归一化值进行定权,然后对其权值乘法组合赋权并对相应的赋权值线性组合.该指标值越小,所选参数越优.进一步采用统计分析方法,选取出最优的小波基与分解尺度.仿真信号分析表明,3种信噪比(8 dB、16 dB、24 dB)下,该指标的效果最好,在信噪比8 dB时,正确率大于50%的小波基个数由2个提升到7个,该指标的稳定性更好.心电信号表明,该指标得出的4层分解尺度使去噪信号更加光滑,波形更加平稳.因此,利用所提指标选取出的最佳参数指导小波去噪具有可行性,能使去噪效果更加理想. 展开更多
关键词 小波去噪 均方根误差 曲率平滑度 乘法组合赋权 统计分析 心电信号
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卫星与天线的神经网络去耦合控制
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作者 葛升民 何赟晟 王磊 《自动化技术与应用》 2025年第8期9-13,32,共6页
为了解决具有解耦机构卫星动力学模型中的非线性环节和系统不确定性,将小波神经网络控制应用于去耦合控制。所设计的系统包含两个神经网络,分别是小波神经网络辨识器和多变量神经网络控制器。小波神经网络辨识器和多变量神经网络比例积... 为了解决具有解耦机构卫星动力学模型中的非线性环节和系统不确定性,将小波神经网络控制应用于去耦合控制。所设计的系统包含两个神经网络,分别是小波神经网络辨识器和多变量神经网络控制器。小波神经网络辨识器和多变量神经网络比例积分微分(proportional-integral-derivative,PID)控制器均采用改进反向传播(backpropagation,BP)神经网络训练方法调整网络结构参数,并在原有梯度下降法的基础上增加动量项,并采用自适应调整学习率的方式。采用加入非线性环节和不确定性因素后的系统模型进行仿真分析。仿真结果表明,所提神经网络控制算法在不依赖于模型参数的情况下能够较好地完成对不确知控制对象的自适应控制,保证了解耦机构的主动阻尼作用。 展开更多
关键词 小波神经网络 多变量PID控制器 不确定性 去耦合控制
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基于小波变换和模糊理论的过电压识别 被引量:1
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作者 李双亮 王庆峰 +1 位作者 李相强 张健穹 《江苏大学学报(自然科学版)》 北大核心 2025年第2期194-199,共6页
为了识别高速动车组列车过电压类型、给故障溯源及列车改进优化提供数据支持,提出了一种模糊识别方法.首先,利用小波变换对过电压时域信号进行db4小波基下的17层分解,在此基础上提取各分解层数下的能量值,并进行数据标准化处理,获得过... 为了识别高速动车组列车过电压类型、给故障溯源及列车改进优化提供数据支持,提出了一种模糊识别方法.首先,利用小波变换对过电压时域信号进行db4小波基下的17层分解,在此基础上提取各分解层数下的能量值,并进行数据标准化处理,获得过电压信号特征量.其次,基于模糊理论,建立起列车升降弓、进分相、出分相、高频谐振、铁磁谐振和VCB操作过电压的标准模型.最后,使用贴近度计算与择近原则完成对过电压的识别.结果表明文中方法对过电压的识别准确率在90%以上. 展开更多
关键词 高速动车组 过电压 小波变换 模糊识别 贴近度 择近原则
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基于多特征空间自适应网络的谐波减速器故障诊断 被引量:2
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作者 陈仁祥 张晓 +2 位作者 李嘉琳 杨宝军 张旭 《振动工程学报》 北大核心 2025年第2期432-440,共9页
由于多测点位置不同引起的数据分布差异造成谐波减速器故障诊断效果不佳,提出基于多特征空间自适应网络(multiple feature spaces adaptation network,MFSAN)的谐波减速器故障诊断方法。对谐波减速器振动信号进行连续小波变换,以构造时... 由于多测点位置不同引起的数据分布差异造成谐波减速器故障诊断效果不佳,提出基于多特征空间自适应网络(multiple feature spaces adaptation network,MFSAN)的谐波减速器故障诊断方法。对谐波减速器振动信号进行连续小波变换,以构造时频图来描述其运行状态特征。将不同位置传感器所测数据划分为多个源域数据和目标域数据映射到不同特征空间,得到不同测点位置下的特征表示。利用自适应网络将源域中学习到的知识自动应用到目标域,以自动对齐特定领域的特征分布,从而学习多个域不变表示。利用领域特定的决策边界来对齐分类器的输出,从而有效减少因传感器位置差异引起的数据分布差异。在工业机器人谐波减速器诊断实验中,所提诊断方法达到了99.72%的准确率,高于其他对比方法,验证了所提诊断方法的有效性和可行性。 展开更多
关键词 故障诊断 谐波减速器 连续小波变换 多特征空间自适应
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基于注意力机制的MWCNN网络的海洋自由表面多次波压制研究
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作者 胡嘉晨 童思友 +5 位作者 尚新民 孙朋朋 王忠成 王士雨 魏皓 辛成庆 《中国海洋大学学报(自然科学版)》 北大核心 2025年第2期89-102,共14页
本文提出了一种基于注意力机制的多级小波变换驱动的卷积神经网络(Multi-level wavelet CNN, MWCNN)来压制海洋地震资料中的自由表面多次波。该方法通过小波变换实现数据特征尺寸的压缩,从而避免传统下采样带来的信息缺失问题。此外,它... 本文提出了一种基于注意力机制的多级小波变换驱动的卷积神经网络(Multi-level wavelet CNN, MWCNN)来压制海洋地震资料中的自由表面多次波。该方法通过小波变换实现数据特征尺寸的压缩,从而避免传统下采样带来的信息缺失问题。此外,它还引入了注意力机制来扩大感受野,提高训练的保真效果。用本文算法与DnCNN网络、U-Net网络分别对不同观测系统下的模拟数据和实际数据进行对比测试,实验结果表明基于注意力机制的MWCNN网络能较好地分离一次波和自由表面多次波,对有效信号的保护比其它两种网络更优秀,具有较强的泛化能力和压制效率。 展开更多
关键词 海洋地震资料 自由表面多次波 多级小波变换驱动的卷积神经网络(MWCNN) 注意力机制
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