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2023 4

2022 3

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2020 5

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关键词

小波分析 4

小波变换 3

故障诊断 2

物元变换 2

CP）；符号间干扰（inter symbol interference， ISI）；载波间干扰（inter carrier interference 1

HHT 1

Hilbert变换 1

ICI）；最大似然估计（maximum likelihood estimation 1

MLE） 1

Mallat算法 1

Meyer小波变换 1

OFDM）；快速傅立叶变换（Fast Fourier transform， FFT）；循环前缀（cyclic prefix 1

Walsh循环谱 1

一氧化碳氧化 1

严格雪崩准则 1

中轴变换；包络；插值；蒙皮；圆 1

亚像元 1

信号处理 1

停机过程 1

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flow regime identification in horizontal tube bundles under vertical upward cross-flow condition using wavelettransform

HUANG Xinghua, WANG Li, JIA Feng

《能源前沿（英文）》 2008年第2卷第3期页码 333-338 doi: 10.1007/s11708-008-0043-0

摘要： A wavelet-transform based approach for flow regime identification in horizontal tube bundles under vertical upward cross-flow condition was presented. Tests on two-phase flow pattern of R134a were conducted under low mass velocity and flow boiling conditions over ranges of mass flux 4–25 kg/ms, vapor quality 0.02–0.90. Time series of differential pressure fluctuations were measured and analyzed with discrete wavelet transform. Different time-scale characteristics in bubbly flow, churn flow and annular flow were analyzed. The wavelet energy distributions over scales were found to be appropriate for flow regime identification. Based on the wavelet energy distribution over characteristic scales, a criterion of flow regime identification was proposed. The comparison with experiment results show that it is feasible to use the discrete wavelet transform as the tool of flow regime identification in horizontal tube bundles under vertical upward cross-flow condition.

关键词： two-phase discrete appropriate wavelet-transform criterion

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Identification of faults through wavelet transform vis-à-vis fast Fourier transform of noisy vibration

null

《机械工程前沿（英文）》 2014年第9卷第2期页码 130-141 doi: 10.1007/s11465-014-0298-6

摘要：

Fault diagnosis of rolling element bearings requires efficient signal processing techniques. For this purpose, the performances of envelope detection with fast Fourier transform (FFT) and continuous wavelet transform (CWT) of vibration signals produced from a bearing with defects on inner race and rolling element, have been examined at low signal to noise ratio. Both simulated and experimental signals from identical bearings have been considered for the purpose of analysis. The bearings have been modeled as spring-mass-dashpot systems and the simulated signals have been obtained considering transfer functions for the bearing systems subjected to impulsive loads due to the defects. Frequency B spline wavelets have been applied for CWT and a discussion on wavelet selection has been presented for better effectiveness. Results show that use of CWT with the proposed wavelets overcomes the short coming of FFT while processing a noisy vibration signals for defect detection of bearings.

关键词： Fault detection spline wavelet continuous wavelet transform fast Fourier transform

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A new acoustic emission source location technique based on wavelet transform and mode analysis

JIAO Jing-pin, HE Cun-fu, WU Bin, FEI Ren-yuan, WANG Xiu-yan

《机械工程前沿（英文）》 2006年第1卷第3期页码 341-345 doi: 10.1007/s11465-006-0006-4

摘要： For wave propagation in dispersive media, the arrival time of the acoustic emission signal to the sensor is dependent on the setting of the threshold voltage, which results in the inaccuracy of the acoustic emission location. Based on the wavelet transform and the theory of modal acoustic emission, a new method is proposed to improve the accuracy of acoustic emission source location. It is believed that the acoustic emission signal propagation in the structure has the characteristics of multi-mode and dispersion, and the acoustic emission source location should use the arrival time to sensors obtained from the output signals not only at the same mode but also at the same frequency. The wavelet transform is used to resolve the problem. By utilizing the time-frequency data of the wavelet, the frequency-dependent arrival time traveling is easily obtained; by numerical computation of the wave s propagation in structure, the group velocity of the guided mode is also obtained, therefore the accuracy source location is realized. The acoustic emission source location experiments were conducted in a thin steel plate and results show that the technique is an effective tool for acoustic emission source location.

关键词： s propagation frequency emission signal signal propagation dispersive

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自适应小波阈值去噪在重力仪信号处理中的应用

赵立业,周百令,李坤宇

《中国工程科学》 2006年第8卷第3期页码 49-52

摘要：

为了有效地消除各种外界干扰噪声对高精度海洋重力仪测量值的影响，提高重力异常测量值的精度，在分析了小波阈值及自适应小波阈值去噪算法的基础上，将其应用到高精度海洋重力仪系统数据处理中，并与自适应卡尔曼滤波做了对比，以处理后信号的信噪比作为衡量3种数据处理方法优劣的依据。理论分析和仿真实验表明，自适应小波阈值去噪方法、传统的小波阈值去噪方法和自适应卡尔曼滤波都能在一定程度上消除噪声信号对重力仪测量信号的影响，但在相同情况下，自适应小波阈值去噪方法具有明显的优越性。

关键词：重力仪信号处理小波变换自适应阈值去噪自适应卡尔曼滤波

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图像边缘检测二维小波算法研究与实现

张红岩,张登攀

《中国工程科学》 2003年第5卷第4期页码 61-64

摘要：

边沿作为图像视觉的最主要特征，成为图像信息获取的重要内容。小波变换具有检测局域突变的能力，而且可以结合多尺度信息进行检测，因此成为图像信息边缘检测的优良工具。根据二维小波变换的特点,分析了利用二维小波进行图像边缘检测的基本原理，并设计了利用二维小波变换进行多尺度边缘匹配的检测算法。基于研究结果，编写了计算机应用程序，进行实例分析。

关键词：小波变换多尺度边缘检测

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子波分析在声辐射和声散射中的应用

文立华,任兴民

《中国工程科学》 2002年第4卷第8期页码 63-68

摘要：

文章提出将子波分析用于求解声学中的边界积分方程，能提高现有边界元方法解决工程问题的能力。在子波分析于声辐射和声散射的应用研究中，提出了把积分核函数用级数展开，建立频率响应函数计算的频率迭代技术，大大提高了频率响应函数的计算效率。讨论了子波分析在声学工程数值计算中的研究前景。

关键词：子波分析声辐射和散射结构声耦合频率响应函数

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五滚柱式定向离合器故障诊断的小波包变换方法

胡斌梁,罗一新,谢明

《中国工程科学》 2005年第7卷第6期页码 66-68

摘要：

论述了小波包分解及其能量谱处理五滚柱式定向离合器故障的原理与方法。应用小波包分解及其能量谱直观地识别出故障的特征频带，并进行了量化分析。结果表明，小波包及小波包分解能量谱比传统的傅立叶分析方法具有更大的优越性和价值。

关键词：故障诊断小波包能量谱离合器

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难加工材料高速切削力非线性特征规律的最大熵谱分析与小波分析

龙震海,王西彬,王好臣

《中国工程科学》 2004年第6卷第10期页码 28-31

摘要：

在切削速度范围157～1000 m/min内，综合应用析因试验与速度单因素试验，对航空用难加工材料2Cr13马氏体不锈钢进行了高速干式铣削试验。在分析其切削力显著性影响因素的基础上，对切削力随机信号进行了现代谱分析与小波分析。研究结果表明，高速切削马氏体不锈钢材料时，切削速度和每齿进给量之间的交互作用对切削力有显著影响；铣削深度和每齿进给量之间的交互作用在切削力响应信号中表现为低频周期信号；低频周期信号与高频信号叠加后，其波形的振幅将会增大。

关键词：难加工材料高速切削析因设计 Meyer小波变换 Mallat算法

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Experimental study of structural damage identification based on modal parameters and decay ratio of acceleration signals

Zhigen WU, Guohua LIU, Zihua ZHANG

《结构与土木工程前沿（英文）》 2011年第5卷第1期页码 112-120 doi: 10.1007/s11709-010-0069-3

摘要： A novel damage assessment method based on the decay ratio of acceleration signals (DRAS) was proposed. Two experimental tests were used to show the efficiency. Three beams were gradually damaged, and then the changes of dynamic parameters were monitored from initial to failure state. In addition, a new method was compared with the linear modal-based damage assessment using wavelet transform (WT). The results clearly show that DRAS increases in linear elasticity state and microcrack propagation state, while DRAS decreases in macrocrack propagation state. Preliminary analysis was developed considering the beat phenomenon in the nonlinear state to explain the turn point of DRAS. With better sensibility of damage than modal parameters, probably DRAS is a promising damage indicator in damage assessment.

关键词： damage assessment decay ratio of acceleration signals (DRAS) wavelet transform (WT) modal analysis reinforced concrete beam beat phenomenon

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Combustion instability detection using the wavelet detail of pressure fluctuations

JI Junjie, LUO Yonghao

《能源前沿（英文）》 2008年第2卷第1期页码 116-120 doi: 10.1007/s11708-008-0019-0

摘要： A combustion instability detection method that uses the wavelet detail of combustion pressure fluctuations is put forward. To confirm this method, combustion pressure fluctuations in a stoker boiler are recorded at stable and unstable combustion with a pressure transducer. Daubechies one-order wavelet is chosen to obtain the wavelet details for comparison. It shows that the wavelet approximation indicates the general pressure change in the furnace, and the wavelet detail magnitude is consistent with the intensity of turbulence and combustion noise. The magnitude of the wavelet detail is nearly constant when the combustion is stable, however, it will fluctuate much when the combustion is unstable.

关键词： comparison wavelet approximation pressure transducer general pressure consistent

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Fault feature extraction of planet gear in wind turbine gearbox based on spectral kurtosis and time wavelet

Yun KONG, Tianyang WANG, Zheng LI, Fulei CHU

《机械工程前沿（英文）》 2017年第12卷第3期页码 406-419 doi: 10.1007/s11465-017-0419-0

摘要：

Planetary transmission plays a vital role in wind turbine drivetrains, and its fault diagnosis has been an important and challenging issue. Owing to the complicated and coupled vibration source, time-variant vibration transfer path, and heavy background noise masking effect, the vibration signal of planet gear in wind turbine gearboxes exhibits several unique characteristics: Complex frequency components, low signal-to-noise ratio, and weak fault feature. In this sense, the periodic impulsive components induced by a localized defect are hard to extract, and the fault detection of planet gear in wind turbines remains to be a challenging research work. Aiming to extract the fault feature of planet gear effectively, we propose a novel feature extraction method based on spectral kurtosis and time wavelet energy spectrum (SK-TWES) in the paper. Firstly, the spectral kurtosis (SK) and kurtogram of raw vibration signals are computed and exploited to select the optimal filtering parameter for the subsequent band-pass filtering. Then, the band-pass filtering is applied to extrude periodic transient impulses using the optimal frequency band in which the corresponding SK value is maximal. Finally, the time wavelet energy spectrum analysis is performed on the filtered signal, selecting Morlet wavelet as the mother wavelet which possesses a high similarity to the impulsive components. The experimental signals collected from the wind turbine gearbox test rig demonstrate that the proposed method is effective at the feature extraction and fault diagnosis for the planet gear with a localized defect.

关键词： wind turbine planet gear fault feature extraction spectral kurtosis time wavelet energy spectrum

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A reversibility-gain model for integer Karhunen-Loève transform design in video coding

Xing-guo ZHU,Lu YU

《信息与电子工程前沿（英文）》 2015年第16卷第10期页码 883-891 doi: 10.1631/FITEE.1500071

摘要： Karhunen-Loève transform (KLT) is the optimal transform that minimizes distortion at a given bit allocation for Gaussian source. As a KLT matrix usually contains non-integers, integer-KLT design is a classical problem. In this paper, a joint reversibility-gain (R-G) model is proposed for integer-KLT design in video coding. Specifically, the ‘reversibility’ is modeled according to distortion analysis in using forward and inverse integer transform without quantization. It not only measures how invertible a transform is, but also bounds the distortion introduced by the non-orthonormal integer transform process. The ‘gain’ means transform coding gain (TCG), which is a widely used criterion for transform design in video coding. Since KLT maximizes the TCG under some assumptions, here we define the TCG loss ratio (LR) to measure how much coding gain an integer-KLT loses when compared with the original KLT. Thus, the R-G model can be explained as follows: subject to a certain TCG LR, an integer-KLT with the best reversibility is the optimal integer transform for a given non-integer-KLT. Experimental results show that the R-G model can guide the design of integer-KLTs with good performance.

关键词： Integer transform Karhunen-Loè ve transform (KLT) Integer-KLT Transform coding Video coding

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基于心理生理信号的个人音乐情感体验识别 Research Articles

Le-kai ZHANG, Shou-qian SUN, Bai-xi XING, Rui-ming LUO, Ke-jun ZHANG

《信息与电子工程前沿（英文）》 2019年第20卷第7期页码 964-974 doi: 10.1631/FITEE.1800101

摘要：重要节点识别对电网安全意义重大。但电网音乐能激发人的情感，这是一个心理生理过程。因此心理生理特征可用于识别个人音乐情感体验。提出一种新的基于人体生理特征的个人音乐情感识别方法。首先，建立一个基于音乐情感特征的数据库和一个基于听音乐产生的生理信号的数据库，包括心电、脉搏、皮温、呼吸和瞳孔直径变化等生理信号。然后，分别采用线性回归、岭回归、三种不同核的支持向量机、决策树、K近邻算法、多层感知器和Nu支持向量回归（NuSVR）方法，通过音乐特征和人体生理特征识别音乐情感。结果显示，NuSVR性能优于其他方法，其唤醒相关系数为0.7347（均方差为0.02323），效价相关系数为0.7902（均方差为0.01485）。最后，对不同数据集进行比较，结果表明所有特征（音乐特征和所有生理特征）数据集在识别中表现最好，唤醒相关系数为0.6499（均方差为0.02932），效价相关系数为0.7735（均方差为0.01576）。本文提供了一种有效的个人音乐情感体验识别方法，可用于个性化音乐推荐。

关键词：音乐；情感识别；生理信号；小波变换

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.: evidence from wavelet analysis

Alper ASLAN, Nicholas APERGIS, Selim YILDIRIM

《能源前沿（英文）》 2014年第8卷第1期页码 1-8 doi: 10.1007/s11708-013-0290-6

摘要： This study investigates the dynamic causal relationship between energy consumption and economic growth in the U.S. at different time scales. The main novelty of the study is that this paper complements the existing studies on the nexus between energy consumption and economic growth by employing the wavelet transformation to obtain different time scales in order to investigate causality between energy consumption and economic growth. This method is first developed by Ramsey and Lampart. Their approach consists of first decomposing the series into time scales by wavelet filters and testing causality of each time scale with the pertinent time scale of the other series separately. The data span from 1973q1 to 2012q1 on a quarterly basis. The main empirical insight is that the causal relationship is stronger at finer time scales, whereas the relationship is less and less apparent at longer time horizons. The results indicate that energy consumption causes economic growth, while the reverse is not true at the original frequency of the data. At the very finest scale the same result arises. However, at coarser scales feedback is observed. In particular, at intermediate time scales the evidence indicates that energy consumption causes economic growth, while the reverse is also true. These empirical findings are expected to be of high importance in terms of the effective design and implementation of energy and environmental policies, especially when a number of countries in the pursuit of high economic growth targets do not pay any serious attention on environmental issues.

关键词： energy consumption economic growth wavelet analysis granger causality

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Prediction of characteristic blast-induced vibration frequency during underground excavation by using wavelettransform

Tae Un PAK; Guk Rae JO; Un Chol HAN

《结构与土木工程前沿（英文）》 2022年第16卷第8期页码 1029-1039 doi: 10.1007/s11709-022-0861-x

摘要： Blast-induced vibration produces a very complex signal, and it is very important to work out environmental problems induced by blasting. In this study, blasting vibration signals were measured during underground excavation in carbonaceous shale by using vibration pickup CB-30 and FFT analyzer AD-3523. Then, wavelet analysis on the measured results was carried out to identify frequency bands reflecting changes of blasting vibration parameters such as vibration velocity and energy in different frequency bands. Frequency characteristics are then discussed in view of blast source distance and charge weight per delay. From analysis of results, it can be found that peak velocity and energy of blasting vibration in frequency band of 62.5–125 Hz were larger than ones in other bands, indicating the similarity to characteristics in the distribution band (31–130 Hz) of main vibration frequency. Most frequency bands were affected by blasting source distance, and the frequency band of 0–62.5 Hz reflected the change of charge weight per delay. By presenting a simplified method to predict main vibration frequency, this research may provide significant reference for future blasting engineering.

关键词： wavelet analysis blast-induced vibration frequency characteristics underground excavation