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Weighted Self-Adaptive Threshold Wavelets for Interpolation Point Selection Used in Interconnect MOR 被引量:1
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作者 Xinsheng Wang Mingyan Yu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2018年第1期39-45,共7页
As process technology development,model order reduction( MOR) has been regarded as a useful tool in analysis of on-chip interconnects. We propose a weighted self-adaptive threshold wavelet interpolation MOR method on ... As process technology development,model order reduction( MOR) has been regarded as a useful tool in analysis of on-chip interconnects. We propose a weighted self-adaptive threshold wavelet interpolation MOR method on account of Krylov subspace techniques. The interpolation points are selected by Haar wavelet using weighted self-adaptive threshold methods dynamically. Through the analyses of different types of circuits in very large scale integration( VLSI),the results show that the method proposed in this paper can be more accurate and efficient than Krylov subspace method of multi-shift expansion point using Haar wavelet that are no weighted self-adaptive threshold application in interest frequency range,and more accurate than Krylov subspace method of multi-shift expansion point based on the uniform interpolation point. 展开更多
关键词 INTERCONNECT model order reduction HAAR wavelet transform weighted threshold multi-shift ARNOLDI circuit synthesis
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Wavelet Density Estimation and Statistical Evidences Role for a GARCH Model in the Weighted Distribution 被引量:1
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作者 Mohammad Abbaszadeh Mahdi Emadi 《Applied Mathematics》 2013年第2期410-416,共7页
We consider n observations from the GARCH-type model: Z = UY, where U and Y are independent random variables. We aim to estimate density function Y where Y have a weighted distribution. We determine a sharp upper boun... We consider n observations from the GARCH-type model: Z = UY, where U and Y are independent random variables. We aim to estimate density function Y where Y have a weighted distribution. We determine a sharp upper bound of the associated mean integrated square error. We also make use of the measure of expected true evidence, so as to determine when model leads to a crisis and causes data to be lost. 展开更多
关键词 Density Estimation GARCH Model weighted Distribution waveletS Statistical Evidences STRONGLY MIXING
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WAVELET CHARACTERIZATION OF WEIGHTED TRIEBEL-LIZORKIN SPACES 被引量:1
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作者 Deng Donggao Xu Ming Yan Lixin (Zhongshan University, China) 《Approximation Theory and Its Applications》 2002年第4期76-92,共17页
In this paper we use wavelets to characterize weighted Triebel-Lizorkin spaces. Our weights belong to the Muckenhoupt class A q and our weighted Triebel-Lizorkin spaces are weighted atomic Triebel-Lizorkin spaces.
关键词 wavelet CHARACTERIZATION OF weighted TRIEBEL-LIZORKIN SPACES
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A Robust Image Watermarking Scheme Using Z-Transform, Discrete Wavelet Transform and Bidiagonal Singular Value Decomposition 被引量:2
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作者 N.Jayashree R.S.Bhuvaneswaran 《Computers, Materials & Continua》 SCIE EI 2019年第1期263-285,共23页
Watermarking is a widely used solution to the problems of authentication and copyright protection of digital media especially for images,videos,and audio data.Chaos is one of the emerging techniques adopted in image w... Watermarking is a widely used solution to the problems of authentication and copyright protection of digital media especially for images,videos,and audio data.Chaos is one of the emerging techniques adopted in image watermarking schemes due to its intrinsic cryptographic properties.This paper proposes a new chaotic hybrid watermarking method combining Discrete Wavelet Transform(DWT),Z-transform(ZT)and Bidiagonal Singular Value Decomposition(BSVD).The original image is decomposed into 3-level DWT,and then,ZT is applied on the HH3 and HL3 sub-bands.The watermark image is encrypted using Arnold Cat Map.BSVD for the watermark and transformed original image were computed,and the watermark was embedded by modifying singular values of the host image with the singular values of the watermark image.Robustness of the proposed scheme was examined using standard test images and assessed against common signal processing and geometric attacks.Experiments indicated that the proposed method is transparent and highly robust. 展开更多
关键词 Digital WATERMARKING chaotic mapping z-transform ARNOLD cat map discrete wavelet transform(DWT) bidiagonal SINGULAR value decomposition(BSVD)
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APPLICATION OF WAVELET THEORY IN RESEARCHON WEIGHT FUNCTION OF MESHLESS METHOD 被引量:1
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作者 张红 张选兵 葛修润 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第5期662-666,共5页
Multiresolution analysis of wavelet theory can give an effective way to describe the information at various levels of approximations or different resolutions, based on spline wavelet analysis,so weight function is ort... Multiresolution analysis of wavelet theory can give an effective way to describe the information at various levels of approximations or different resolutions, based on spline wavelet analysis,so weight function is orthonormally projected onto a sequence of closed spline subspaces, and is viewed at various levels of approximations or different resolutions. Now, the useful new way to research weight function is found, and the numerical result is given. 展开更多
关键词 meshless method weight function spline wavelet multiresolution analysis
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Radar emitter signal recognition based on multi-scale wavelet entropy and feature weighting 被引量:16
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作者 李一兵 葛娟 +1 位作者 林云 叶方 《Journal of Central South University》 SCIE EI CAS 2014年第11期4254-4260,共7页
In modern electromagnetic environment, radar emitter signal recognition is an important research topic. On the basis of multi-resolution wavelet analysis, an adaptive radar emitter signal recognition method based on m... In modern electromagnetic environment, radar emitter signal recognition is an important research topic. On the basis of multi-resolution wavelet analysis, an adaptive radar emitter signal recognition method based on multi-scale wavelet entropy feature extraction and feature weighting was proposed. With the only priori knowledge of signal to noise ratio(SNR), the method of extracting multi-scale wavelet entropy features of wavelet coefficients from different received signals were combined with calculating uneven weight factor and stability weight factor of the extracted multi-dimensional characteristics. Radar emitter signals of different modulation types and different parameters modulated were recognized through feature weighting and feature fusion. Theoretical analysis and simulation results show that the presented algorithm has a high recognition rate. Additionally, when the SNR is greater than-4 d B, the correct recognition rate is higher than 93%. Hence, the proposed algorithm has great application value. 展开更多
关键词 雷达辐射源 特征加权 信号识别 小波熵 多尺度 特征提取 自适应雷达 电磁环境
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LKAW: A Robust Watermarking Method Based on Large Kernel Convolution and Adaptive Weight Assignment
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作者 Xiaorui Zhang Rui Jiang +3 位作者 Wei Sun Aiguo Song Xindong Wei Ruohan Meng 《Computers, Materials & Continua》 SCIE EI 2023年第4期1-17,共17页
Robust watermarking requires finding invariant features under multiple attacks to ensure correct extraction.Deep learning has extremely powerful in extracting features,and watermarking algorithms based on deep learnin... Robust watermarking requires finding invariant features under multiple attacks to ensure correct extraction.Deep learning has extremely powerful in extracting features,and watermarking algorithms based on deep learning have attracted widespread attention.Most existing methods use 3×3 small kernel convolution to extract image features and embed the watermarking.However,the effective perception fields for small kernel convolution are extremely confined,so the pixels that each watermarking can affect are restricted,thus limiting the performance of the watermarking.To address these problems,we propose a watermarking network based on large kernel convolution and adaptive weight assignment for loss functions.It uses large-kernel depth-wise convolution to extract features for learning large-scale image information and subsequently projects the watermarking into a highdimensional space by 1×1 convolution to achieve adaptability in the channel dimension.Subsequently,the modification of the embedded watermarking on the cover image is extended to more pixels.Because the magnitude and convergence rates of each loss function are different,an adaptive loss weight assignment strategy is proposed to make theweights participate in the network training together and adjust theweight dynamically.Further,a high-frequency wavelet loss is proposed,by which the watermarking is restricted to only the low-frequency wavelet sub-bands,thereby enhancing the robustness of watermarking against image compression.The experimental results show that the peak signal-to-noise ratio(PSNR)of the encoded image reaches 40.12,the structural similarity(SSIM)reaches 0.9721,and the watermarking has good robustness against various types of noise. 展开更多
关键词 Robust watermarking large kernel convolution adaptive loss weights high-frequency wavelet loss deep learning
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加权核范数最小化和改进小波阈值函数的图像去噪算法
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作者 郭昕刚 许连杰 +1 位作者 程超 霍金花 《国防科技大学学报》 EI CAS CSCD 北大核心 2024年第2期238-246,共9页
针对加权核范数最小化算法存在结构残余噪声以及无法较好地保持图像边缘结构的问题,提出基于加权核范数最小化和改进小波阈值函数的图像去噪算法。利用全变分模型对噪声图像进行初步去噪,使用噪声图像与初步去噪后的图像进行差分运算,... 针对加权核范数最小化算法存在结构残余噪声以及无法较好地保持图像边缘结构的问题,提出基于加权核范数最小化和改进小波阈值函数的图像去噪算法。利用全变分模型对噪声图像进行初步去噪,使用噪声图像与初步去噪后的图像进行差分运算,对差分后得到的噪声残差图像使用改进的小波阈值函数去噪,将小波去噪后的残差图像与初步去噪图像叠加,将叠加后的图像使用基于残余噪声水平迭代的加权核范数最小化算法进行二次去噪。相较于当下主流去噪算法,经该算法处理后的图像的PSNR和SSIM值均有所提升,能够更好地保持图像的纹理结构,且在高噪声环境下效果更佳。 展开更多
关键词 加权核范数 小波变换 噪声残差 全变分
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基于ARMA和GRU的数据权重负载预测
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作者 王松 《计算机应用文摘》 2024年第10期53-55,共3页
文章将小波分解与自回归滑动平均模型(ARMA)和门控循环单元(GRU)结合起来,用于预测接下来几个时间间隔内的用户负载。为了降低数据中随机因素对模型的影响,对数据进行了加权处理。该方法首先通过Savitzky-Golay滤波对时间序列进行平滑处... 文章将小波分解与自回归滑动平均模型(ARMA)和门控循环单元(GRU)结合起来,用于预测接下来几个时间间隔内的用户负载。为了降低数据中随机因素对模型的影响,对数据进行了加权处理。该方法首先通过Savitzky-Golay滤波对时间序列进行平滑处理,然后利用小波分解将平滑后的时间序列分解为2个分量。 展开更多
关键词 小波分解 ARMA GRU 数据权重
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基于面积加权GWT-GFT的水声目标识别
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作者 陈鑫 邵杰 +2 位作者 王星星 杨鑫 杨世逸林 《计算机技术与发展》 2024年第7期108-115,共8页
由于海洋环境的复杂性,水声目标的识别具有很大的挑战性。为解决这类复杂环境下特征提取的问题,提出了一种基于面积加权的图小波变换-图傅里叶变换(GWT-GFT)的分析方法。在完成数据预处理后,为了能够凸显顶点之间的关系,提出了一种新的... 由于海洋环境的复杂性,水声目标的识别具有很大的挑战性。为解决这类复杂环境下特征提取的问题,提出了一种基于面积加权的图小波变换-图傅里叶变换(GWT-GFT)的分析方法。在完成数据预处理后,为了能够凸显顶点之间的关系,提出了一种新的基于顶点三角形面积的加权方法来构建图信号;构建好的图信号通过GWT分解为多尺度图分量;然后,利用GFT将这些分量从图域变换到特征值谱域进行分析;在此基础上,提取各分量特征值谱的特征;最后,利用基于高斯核函数的支持向量机(SVM)对获取的特征向量进行分类。基于水声信号ShipsEar数据库,采用5折交叉验证方法进行验证。与现有的其它方法相比,所提的模型以36个特征在376656个样本上取得了97.22%的准确率,证明了该分析方法的有效性和鲁棒性。 展开更多
关键词 水声目标识别 GWT-GFT 特征提取 图信号处理 顶点三角形面积加权
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基于小波去噪与改进Canny算法的带钢表面缺陷检测 被引量:1
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作者 崔莹 赵磊 +1 位作者 李恒 刘辉 《现代电子技术》 北大核心 2024年第4期148-152,共5页
针对带钢表面图像亮度不均匀、对比度低以及缺陷种类多、形式复杂的问题,提出一种基于小波去噪与改进Canny算法的带钢表面缺陷检测算法。首先通过小波变换将原始图像分解,对低频分量采用改进的同态滤波提高亮度和对比度,对高频分量采用... 针对带钢表面图像亮度不均匀、对比度低以及缺陷种类多、形式复杂的问题,提出一种基于小波去噪与改进Canny算法的带钢表面缺陷检测算法。首先通过小波变换将原始图像分解,对低频分量采用改进的同态滤波提高亮度和对比度,对高频分量采用改进的阈值函数进行去噪,并通过小波重构得到增强图像。其次对传统Canny算法进行改进,通过改进的自适应加权中值滤波进行平滑,并增加梯度方向模板;然后采用迭代式最优阈值选择法与最大类间方差法来求取高低阈值,提高算法的自适应性。最后采用形态学处理对缺陷边缘填充,并去除干扰边缘及毛刺,得到带钢表面缺陷区域。实验结果表明,所提算法对带钢表面缺陷的检测效果较好、精度较高,适用于多种类型的带钢表面缺陷检测。 展开更多
关键词 小波去噪 CANNY算法 带钢表面缺陷检测 同态滤波 自适应加权中值滤波 形态学处理
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一种暂态电能质量检测新方法的研究
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作者 周滨 嵇建波 +2 位作者 徐龙 张文 柏元忠 《电力大数据》 2024年第2期1-10,共10页
电能质量扰动会带来复杂信号调制特性,使得从电能质量监测数据中提取扰动信号特征面临困难。为提高噪声背景下复合电能质量扰动检测准确性,本文采用自适应无参经验小波变换(adaptiveparameterless empirical wavelet transform,APEWT)... 电能质量扰动会带来复杂信号调制特性,使得从电能质量监测数据中提取扰动信号特征面临困难。为提高噪声背景下复合电能质量扰动检测准确性,本文采用自适应无参经验小波变换(adaptiveparameterless empirical wavelet transform,APEWT)对扰动信号进行模态分解,进而基于频率加权能量算子(frequency-weighted energy operator,FWEO)对单模态分量进行能量计算,同时通过解调提取用于扰动定位的瞬时频率和幅值特征量。一方面,APEWT中基于自适应频带分割的小波滤波器组输出仅包含有效模态分量,有效避免了模态混叠现象的出现;另一方面,FWEO噪声鲁棒性有效提高了强噪声背景下扰动特征提取的准确性。将算法应用到仿真及实测信号,结果显示该方法能够有效地追踪扰动信号的瞬时变化,且解调得到的瞬时频率和幅值也进一步证明了方法的可行性和有效性。 展开更多
关键词 电能质量 自适应无参经验小波变换 频率加权能量算子 扰动检测 模态混叠
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基于数据挖掘的新旧动能转换成效监测体系研究 被引量:1
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作者 卢兆军 谢红涛 郝泉 《自动化技术与应用》 2024年第2期169-172,共4页
采用目前方法构建新旧动能转换成效监测体系时,没有对监测数据进行去噪处理,导致方法的监测精度和敏感度较低。为此,提出基于数据挖掘的新旧动能转换成效监测体系研究方法。首先确定构建新旧动能转换成效监测体系的具体步骤,其次在双树... 采用目前方法构建新旧动能转换成效监测体系时,没有对监测数据进行去噪处理,导致方法的监测精度和敏感度较低。为此,提出基于数据挖掘的新旧动能转换成效监测体系研究方法。首先确定构建新旧动能转换成效监测体系的具体步骤,其次在双树复小波原理的基础上对监测数据进行去噪处理,利用数据挖掘方法构建新旧动能转换成效监测指标体系,并对监测指标进行标准化处理,最后结合熵权法和非线性加权模型完成新旧动能转换成效的监测。实验结果表明所提方法的监测精度和敏感度较高。 展开更多
关键词 数据挖掘 双树复小波原理 层次分析法 非线性加权模型 新旧动能转换成效监测
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图像处理中应用图像降噪算法的研究综述
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作者 白茹鑫 栾尚敏 《现代信息科技》 2024年第10期21-25,31,共6页
日常生活中,在发送、存储图像和拍照形成图像的过程中往往会因操作不当而导致图像不清晰,无法反映图像本质。为此采用图像降噪算法将图像中的杂质去除,还原出无噪声的图像,同时还可以使大部分的细节因素保留在图片中,让图片更加清晰。... 日常生活中,在发送、存储图像和拍照形成图像的过程中往往会因操作不当而导致图像不清晰,无法反映图像本质。为此采用图像降噪算法将图像中的杂质去除,还原出无噪声的图像,同时还可以使大部分的细节因素保留在图片中,让图片更加清晰。在去噪方法的运用上通常是采用无噪图像和含有噪声的先验信息,但弊端是二者并没有进行有效的结合。为了解决这个问题,采用小波、非局部均值等方式进行去噪,并且在非局部均值去噪中从欧氏距离和权重分配方面进行一些优化。 展开更多
关键词 图像去噪 小波去噪 非局部均值 欧氏距离 权重
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Performance Evaluation of Wavelet Based on Human Visual System
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作者 胡海平 莫玉龙 《Journal of Shanghai University(English Edition)》 CAS 2002年第3期216-220,共5页
We have constructed a compactly supported biorthogonal wavelet that approximates the modulation transfer function (MTF) of human visual system in the frequency domain. In this paper, we evaluate performance of the con... We have constructed a compactly supported biorthogonal wavelet that approximates the modulation transfer function (MTF) of human visual system in the frequency domain. In this paper, we evaluate performance of the constructed wavelet, and compare it with the widely used Daubechies 9 7, Daubechies 9 3 and GBCW 9 7 wavelets. The result shows that coding performance of the constructed wavelet is better than Daubechies 9 3, and is competitive with Daubechies 9 7 and GBCW 9 7 wavelets. Like Daubechies 9 3 wavelet, the filter coefficients of the constructed wavelet are all dyadic fractions, and the tap is less than Daubechies 9 7 and GBCW 9 7. It has an attractive feature in the realization of discrete wavelet transform. 展开更多
关键词 biorthogonal wavelet REGULARITY peak to peak ratio weighted subband coding gain.
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Extraction of failure characteristic of rolling element bearing based on wavelet transform under strong noise
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作者 张辉 王淑娟 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第2期169-172,共4页
There has been a lot of research has been performed regarding diagnosing rolling element bearing faults using wavelet analysis, but almost all methods are not ideal for picking up fault signal characteristics under st... There has been a lot of research has been performed regarding diagnosing rolling element bearing faults using wavelet analysis, but almost all methods are not ideal for picking up fault signal characteristics under strong noise. Therefore, this paper proposes auto-correlation, cross-correlation and weighted average fault diagnosis methods based on wavelet transform (WT) de-noising which combine correlation analysis with WT for the first time. These three methods compute the auto-correlation, the cross-correlation and the weighted average of the measured vibration signals, then de-noise by thresholding and computing the auto-correlation of de-noised coefficients of WT and FFT of energy sequence. The simulation results indicate that all methods enhance the capabilities of fault diagnosis of rolling bearings and pick up the fault characteristics effectively. 展开更多
关键词 旋转轴承 微波转换 交叉关系 噪音强度
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Model identification of hydraulic flight simulator based on improved particle swarm optimization and wavelet analysis
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作者 郭敬 董彦良 +1 位作者 赵克定 郭治富 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第5期656-660,共5页
A new model identification method of hydraulic flight simulator adopting improved particle swarm optimization (PSO) and wavelet analysis is proposed for achieving higher identification precision.Input-output data of h... A new model identification method of hydraulic flight simulator adopting improved particle swarm optimization (PSO) and wavelet analysis is proposed for achieving higher identification precision.Input-output data of hydraulic flight simulator were decomposed by wavelet multiresolution to get the information of different frequency bands.The reconstructed input-output data were used to build the model of hydraulic flight simulator with improved particle swarm optimization with mutation (IPSOM) to avoid the premature convergence of traditional optimization techniques effectively.Simulation results show that the proposed method is more precise than traditional system identification methods in operating frequency bands because of the consideration of design index of control system for identification. 展开更多
关键词 粒子群优化算法 飞行模拟器 小波分析 鉴定方法 水力模型 小波多分辨率分解 基础 输出数据
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基于时频感知加权的车辆路面冲击声品质评价
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作者 朱洪林 宋帅 +3 位作者 吴昱东 杨明亮 税永波 丁渭平 《西南交通大学学报》 EI CSCD 北大核心 2023年第2期296-303,共8页
为表征与量化人对路面冲击声的主观感受,首先,对减速带工况冲击非平稳噪声信号进行声时感知时长定义,同时根据人耳听声可辨性将声时历程分为冲击段、峰值段及衰减段;进而,以小波变换提取冲击噪声中的主冲击与多重微冲击特征信息,组成冲... 为表征与量化人对路面冲击声的主观感受,首先,对减速带工况冲击非平稳噪声信号进行声时感知时长定义,同时根据人耳听声可辨性将声时历程分为冲击段、峰值段及衰减段;进而,以小波变换提取冲击噪声中的主冲击与多重微冲击特征信息,组成冲击声品质评价的基础特征阵;然后,类比峰值因子法定义频域滤波因子,并基于序关系分析法确定时变感知加权系数,组建时频滤波网络对基础特征阵加权且建立冲击声品质时频感知评价指标;最后,基于实车过减速带冲击噪声测试数据计算声品质指标,并进行对比验证.研究结果表明:所提时频感知加权评价指标与主观评价的相关系数在车速20 km/h时为0.927,在车速30 km/h时为0.922;在考虑路面冲击声声时历程全程评价时,经典的声品质评价指标(特征频带时变响度)与主观评价的相关系数在车速20 km/h时为0.933,在车速30 km/h时为0.649;所提时频感知加权评价方法对于车速为20 km/h与30 km/h的情况具有较好的适用性. 展开更多
关键词 路面冲击 声品质 声时感知时长 小波变换 时频感知加权
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Face Recognition Using LDA with Wavelet Transform Approach
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作者 Neeta Nain Akshay Kumar +3 位作者 Amlesh Kumar Mohapatra Ashok Kumar Ratan Das Nemi Chand Singh 《Computer Technology and Application》 2011年第5期401-405,共5页
关键词 人脸识别系统 小波变换方法 LDA 线性判别分析 性能标准 主成分分析 时间复杂性 特征提取
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多策略融合改进的自适应被囊群算法
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作者 柴岩 李广友 +1 位作者 任生 许兆楠 《计算机应用研究》 CSCD 北大核心 2023年第9期2694-2703,2712,共11页
针对被囊群算法全局搜索不充分和易陷入局部极值等问题,提出一种多策略融合改进的自适应被囊群算法(MITSA)。首先,在种群初始化中引入佳点集理论提升种群多样性;其次,提出一种多精英协同引导机制优化被囊个体位置信息,增大对未知搜索区... 针对被囊群算法全局搜索不充分和易陷入局部极值等问题,提出一种多策略融合改进的自适应被囊群算法(MITSA)。首先,在种群初始化中引入佳点集理论提升种群多样性;其次,提出一种多精英协同引导机制优化被囊个体位置信息,增大对未知搜索区域的勘探可能性以增强算法全局探索能力;然后将自适应权重因子引入群体行为阶段,动态平衡算法的全局与局部搜索性能;接着,为增强算法的抗停滞能力,采用依概率小波变异策略实现个体动态微调,同时利用贪婪原则保留优异信息助推种群向食物源靠近;最后基于Markov链理论对改进算法的全局收敛性进行分析论证。通过对基准测试函数和CEC2014复杂函数进行数值仿真,实验结果与Wilcoxon秩和检验结果综合验证了MITSA具有优越的收敛精度、稳健的鲁棒性和高维可拓展性。 展开更多
关键词 被囊群算法 佳点集 多精英协同引导 自适应权重 小波变异
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