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hilbert-huang transform and wavelet analysis of time history signal

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Acta Seismologica Sinica(English Edition) 2003年第4期16卷 422-429页

作者：石春香罗奇峰 Reduction Tongji University Shanghai 200092 China

The brief theories of wavelet analysis and hilbert-huang transform (HHT) are introduced firstly in the present paper. Then several signal data were analyzed by using wavelet and HHT methods, respectively. The comparison shows that HHT is not only an effective method for analyzing non-stationary data, but also is a useful tool for examining detailed characters of time history signal.

关键词： hilbert-huang transform wavelet analysis mother wavelet intrinsic mode functions spectral analysis

同方期刊数据库

A new method for identifying flow pattern of spouted fluidized bed by coupling hilbert-huang transform characteristics of differential pressure signals in different zones

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Particuology 2024年第6期89卷 67-78页

作者： Yongzhi Mei Yang Wang Lihui Zhang Feng Duan School of Energy and Environment Anhui University of TechnologyMaanshan243002China Wuhu Technology and Innovation Research Institute Wuhu241000China Wuhu Cigarette Factory of China Tobacco Anhui Industrial Co. Ldt.Wuhu241002China

On a cold spouted fluidized bed,this study compares the characteristic differences in intrinsic mode function(IMF)energy and hilbert–huang spectrum between the spout zone and annulus zone under different combinations of spouted gas and fluidized gas flow rates for five typical flow *** energy distribution characteristics under different flow patterns are also *** hilbert–huang spectrum and IMF energy of pressure difference signals exhibit distinct variations in different zones as the flow pattern ***,there exists a correlation between the energy in the middle-frequency range and the flow *** the K-means algorithm,the middle-frequency range energy of IMFs in the spout zone and annulus zone is subjected to clustering analysis,leading to the identification of partition boundaries for each flow *** on this,a flow pattern identification method of spouted fluidized bed coupled with middle-frequency range energy in spout zone and annulus zone is proposed,which has very high identification accuracy.

关键词： Spouted fluidized bed Flow pattern Zoning signal Flow pattern transition hilbert-huang transform

A technique to improve the empirical mode decomposition in the hilbert-huang transform

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Earthquake Engineering and Engineering Vibration 2003年第1期2卷 75-86页

作者：陈扬波冯青 Civil & Environmental Engineering University of CaliforniaIrvineCA 92697USA Ph.D Student Civil & Environmental Engineering University of CaliforniaIrvineCA 92697USA Professor

The hilbert-based time-frequency analysis has promising capacity to reveal the time-variant behaviors of a sys- *** admit well-behaved hilbert transforms,component decomposition of signals must be performed *** was first systematically implemented by the empirical mode decomposition(EMD)in the hilbert-huang transform,which can provide a time-frequency representation of the *** EMD,however,has limitations in distinguishing different components in narrowband signals commonly found in free-decay vibration *** this study,a technique for decompo- sing components in narrowband signals based on waves' beating phenomena is proposed to improve the EMD,in which the time scale structure of the signal is unveiled by the hilbert transform as a result of wave beating,the order of component ex- traction is reversed from that in the EMD and the end effect is *** proposed technique is verified by performing the component decomposition of a simulated signal and a free decay signal actually measured in an instrumented bridge *** addition,the adaptability of the technique to time-variant dynamic systems is demonstrated with a simulated time-variant MDOF system.

关键词： time-frequency analysis hilbert-huang transform component decomposition

Application of hilbert-huang transform to the Analysis of the Landslides Triggered by the Wenchuan Earthquake

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Journal of Mountain Science 2015年第3期12卷 711-720页

作者： YANG Chang-wei ZHANG Jian-jing BI Jun-wei School of Civil Engineering Key of Transportation Tunnel EngineeringMinistry of EducationSouthwest Jiaotong University State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology

A steep rock hill with two side slopes located at DK30＋256 of National Road 213 was used as a prototype for analysis. The full process from initial deformation to sliding of the slope during ground shaking was simulated by using a new Continuum-based Discrete Element Method. During the earthquake, when shaking amplitudes were lower, the stress concentration points firstly appeared at the top of the slip mass, and then some tension failure points appeared, followed by shear failure points. At the same time, both the instantaneous frequencies of accelerations in the bedrock and that in the slip mass basically stayed in two different ranges. The energy transmittance coefficients of the sliding surface also stayed in a high range. As the ground shaking lasted, the number of failure points gradually increased until landslide occurrence. The instantaneous frequencies of accelerations in the slip mass and the energy transmittance coefficients of sliding surface gradually decreased, and both finally converged to a lower range. And then, the reasons triggering landslides are analysis in the joint time-frequency domain using hilbert-huang transform, as follows： the differenees of distribution and dissipation of the earthquake energy and the inconsistency of movements between the slip mass and the bedrock were the two major influence factors.

关键词： Discrete Element Method hilbert-huang transform Wenchuan Earthquake Landslide

Application of hilbert-huang transform to denoising in vortex flowmeter

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Journal of Central South University of Technology 2006年第5期13卷 501-505页

作者：孙志强周孑民周萍 School of Energy Science and Engineering Central South University

Due to piping vibration, fluid pulsation and other environmental disturbances, variations of amplitude and frequency to the raw signals of vortex flowmeter are imposed. It is difficult to extract vortex frequencies which indicate volumetric flowrate from noisy data, especially at low flowrates. hilbert-huang transform was adopted to estimate vortex frequency. The noisy raw signal was decomposed into different intrinsic modes by empirical mode decomposition, the time-frequency characteristics of each mode were analyzed, and the vortex frequency was obtained by calculating partial mode’s instantaneous frequency. Experimental results show that the proposed method can estimate the vortex frequency with less than 2% relative error; and in the low flowrate range studied, the denoising ability of hilbert-huang transform is markedly better than Fourier based algorithms. These findings reveal that this method is accurate for vortex signal processing and at the same time has strong anti-disturbance ability.

关键词： flow measurement vortex flowmeter denoising hilbert-huang transform signal processing

Applications of the hilbert-huang transform for Microtremor Data Analysis Enhancement

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Journal of Earth Science 2015年第6期26卷 799-806页

作者： Lanbo Liu Robert Mehl Weijun Wang Qi-Fu Chen Department of Civil & Environmental Engineering University University of Connecticut Center for Integrative Geosciences University of Connecticut Institute of Earthquake Science China Earthquake Administration

In this paper we discuss the use of the hilbert-huang transform（HHT） to enhance the time-frequency analysis of microtremor measurements. HHT is a powerful algorithm that combines the process of empirical mode decomposition（EMD） and the hilbert transform to compose the hilberthuang spectrum that contains the time-frequency-energy information of the recorded signals. HHT is an adaptive algorithm and does not require the signals to be linear or stationary. HHT is advantageous for analyzing microtremor data, since observed microtremors are commonly contaminated by nonstationary transient noises close to the recording instruments. This is especially true when microtremors are measured in an urban environment. In our data processing HHT was used to（1） eliminate the unwanted short-duration transient constituents from microtremor data and use only the coherent portion of the data to carry out the widely used horizontal to vertical spectral ratio（H/V） method;（2） identify and eliminate the continuous industrial noise in certain frequency band; and（3） enhance the H/V analysis by using the hilbert-huang spectrum（HHS）. The efficacy of this proposed approach is demonstrated by the examples of applying it to microtremor data acquired in the metropolitan Beijing area.

关键词： hilbert-huang transform microtremor time-frequency HN engineering earthquake.

Distortion Identification Technique Based on hilbert-huang transform in Video Stabilization

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Transactions of Tianjin University 2011年第1期17卷 68-74页

作者：刘艳邹谋炎王强 Graduate University Chinese Academy of Sciences Institute of Electronics Chinese Academy of Sciences School of Sciences Tianjin University

A distortion identification technique is presented based on hilbert-huang transform to identify distortion model and distortion frequency of distorted real-world image sequences. The distortion model is identified simply based on hilbert marginal spectral analysis after empirical mode decomposing. And distortion frequency is identified by analyzing the occurrence frequency of instantaneous frequency components of every intrinsic mode functions. Rational digital frequency filter with suitable cutoff frequency is designed to remove undesired fluctuations based on identification results. Experimental results show that this technique can identify distortion model and distortion frequency of displacement sequence accurately and efficiently. Based on identification results, distorted image sequence can be stabilized effectively.

关键词： image sequence distortion video stabilization distortion model identification distortion frequency identification hilbert-huang transform

Lamb Wave Arrival Time Extraction Using hilbert-huang transform for Improved Tomography Image

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Journal of Donghua University(English Edition) 2009年第5期26卷 503-508页

作者：张海燕孙修立樊仕轩 Key Laboratory of Specialty Fiber Optics and Optical Access Networks School of Communication and Information EngineeringShanghai University

Travel time Lamb wave tomography has been shown to be an effective nondestructive evaluation （NDE） technique for plate-like structures. The methods used previously to extract arrival times of the fastest or multi Lamb wave modes are mostly based on various timefrequency methods such as Wigner-Ville distribution, shorttime Fourier transform, and recently explored wavelet transform（WT）. Frankly speaking, uses of these signal processing methods improve the accuracy of the arrival time extraction to a great extent relative to directly extract arrival times in time-domain from Lamb waveforms. hilbert-huang transform（HHT） is also an efficient way for analyzing and processing non-stationary signals. The resolving power of time and frequency is restricted from Heisenberg principle in wavelet analysis, while in HHT, the time resolving power is precise and steady, and frequency resolving power is adaptive according to signal intrinsic characteristics. Conclusion can be made that the HI-IT method is more adaptive than WT anal;/sis in ~.!~M~ zing non-stationary signals. Based on the abo~, ~tiaf method is attempted to extract arrival times from Lamb waveforms in this paper. The Lamb wave tomography images generated with arrival times from HHT method were compared with those of WT. The results show that the new method improves the quality of tomography image, which demonstrates the applicability of HHT method in extracting arrival times of Lamb waves.

关键词： Lamb waves tomography hilbert-huang transform nondestructive evaluation

Prediction of Protein Subcellular Localization Based on hilbert-huang transform

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Wuhan University Journal of Natural Sciences 2012年第1期17卷 48-54页

作者： SONG Chaohong SHI Feng College of Science Huazhong Agricultural UniversityWuhan 430070HubeiChina

Using hilbert-huang transform, subcellular localization tbr prokaryotic and eukaryotic proteins was predicted and tested with Reinhart and Hubbard＇s dataset. The prediction accu- racy of prokaryotic and eukaryotic protein sequences concentrated in the dataset all reached 100% by self-consistency, 91.8% for the former and 88% for the latter by the five fold cross-validation test. A significant improvement in prediction quality by incorporating the spectrum parameters with the conventional amino acid composition was observed. One of the crucial merits of this approach is that many existing tools in mathematics and engineering can be easily applied in the predicting process. It is anticipated that digital signal processing may serve as a useful vehicle for many other protein science areas.

关键词： hilbert-huang transform subeellular location support vector machine prokaryotic protein eukaryotic protein