Long-Term Precipitation Analysis and Estimation of Precipitation Concentration Index Using Three Support Vector Machine Methods by Milan Gocic, Shahaboddin Shamshirband, Zaidi Razak, Dalibor Petković, Sudheer Ch, Slavisa Trajkovic

“…For the purpose of PCI prediction, three Support Vector Machine (SVM) models, namely, SVM coupled with the discrete wavelet transform (SVM-Wavelet), the firefly algorithm (SVM-FFA), and using the radial basis function (SVM-RBF), were developed and used. …”
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Study on the Damage Diagnosis of Ancient Wood Structure in Tianshui under Traffic Excitation by Xin Wang, Zhaobo Meng, Xicheng Zhang

“…The node acceleration response signals on beams were decomposed with a wavelet packet. The wavelet packet energy curvature difference index was proposed to determine the structural damage location. …”
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A Novel Fault Diagnosis Approach for Rolling Bearing Based on CWT and Adaptive Sparse Representation by Xing Yuan, Huijie Zhang, Hui Liu

“…Extraction and enhancement of weak impulse signature is the key of rolling bearing fault prognostics in which case the features are often weak and covered by noise. Tunable Q-factor wavelet transform (TQWT), as an emerging wavelet construction theory developed in a frequency domain explicitly, has the advantages of matching with the specific oscillation behavior of signal components. …”
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Research on the risk spillover effect between China's national carbon emissions trading market and crude oil futures market. by XueRong Bai, Yan Chen, Fan Yang

“…Methods such as wavelet energy decomposition, wavelet correlation, lead-lag analysis, and wavelet coherence are used to explore the mean spillover effects and volatility spillover effects (collectively referred to as risk spillover effects) across various scales. …”
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The Influence of Interference Layer on the Prediction of Seismic Information of Channel Sedimentary Reservoir by Xiangsheng Bao, Zhanhu Cai, Qingzhen Wang, Junfeng Yu, Yecheng Li

“…When the lithological composition is relatively stable, the degree of interference of the interference layer is closely related to the seismic wavelet, and it is especially susceptible to the main frequency of the seismic wavelet. …”
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Design of Pulse Waveform for Waveform Division Multiple Access UWB Wireless Communication System by Zhendong Yin, Zhirui Wang, Xiaohui Liu, Zhilu Wu

“…A new multiple access scheme, Waveform Division Multiple Access (WDMA) based on the orthogonal wavelet function, is presented. After studying the correlation properties of different categories of single wavelet functions, the one with the best correlation property will be chosen as the foundation for combined waveform. …”
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A New Method of Denoising of Vibration Signal and Its Application by Feng Miao, Rongzhen Zhao, Xianli Wang

“…Secondly, an improved self-adaptive wavelet packet denoising technique is used to remove the residual white noise. …”
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Change Characteristics and Correlation Analysis of Temperature and Rainfall in Recent 60 Years in Suzhou, Jiuquan by FENG Shiyuan, LI Qingguo, GUO Yang, ZHENG Shuai

“…Combined with R/S analysis, the Hurst index is 0.5578, whichindicates that the rainfall will continue to rise in the future. The continuous wavelet indicatesthat the annual rainfall and temperature has periodicity,while the cross-wavelet and waveletcoherence spectrum indicate that there is the correlation and resonance cycle ina period of timebetween the annual rainfall and temperature.…”
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Approach to Predict Land Subsidence in Old Goafs considering the Influence of Engineering Noise by Chao Du, Fajin Zu, Chunpeng Han

“…Combining the actual engineering subsidence monitoring data of the old goaf, compared with the prediction results of the LSTM and RNN models without DB wavelet decomposition and the gray model GM (1,1), the results show that the DB wavelet has an obvious improvement effect in reducing the influence of measurement data noise on prediction error. …”
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Structural Damage Identification Based on the Transmissibility Function and Support Vector Machine by Yansong Diao, Xue Men, Zuofeng Sun, Kongzheng Guo, Yumei Wang

“…Then two damage features, namely, wavelet packet energy vector and the low order principal components, are constructed by analyzing the amplitude of the transmissibility function with wavelet packet decomposition and principal component analysis separately. …”
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Prediction of shallow bit position based on vibration signal monitoring of bit broken rock by Jinping Yu, Deyong Zou

“…The signal is decomposed by wavelet in the time and frequency domains, and the wavelet energy coefficients of each frequency band are extracted. …”
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Revisiting the Question: The Cause of the Solar Cycle Variation of Total Solar Irradiance by N. B. Xiang

“…In order to understand the cause of the solar cycle variation of TSI, we use extension of wavelet transform, wavelet coherence (WTC), and partial wavelet coherence (PWC), to revisit this issue. …”
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Multilayered Infinite Medium Subject to a Moving Load: Dynamic Response and Optimization Using Coiflet Expansion by Piotr Koziol, M.M. Neves

“…A wavelet based approach is proposed in this paper for analysis and optimization of the dynamical response of a multilayered medium subject to a moving load with respect to the material properties and thickness of supporting half-space. …”
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Research on Recognition of Quiet Period of Sandstone Acoustic Emission Based on Four Machine Learning Algorithms by Dong Duan, Xiaojing Feng, Ruizhe Zhang, Xiaoyu Chen, Hongzhi Zhang

“…In the process of establishing the model, the time domain data of acoustic emission were standardized and processed by box diagram method, so as to clean the abnormal data and reduce the dimension, and the frequency domain data were denoised by wavelet four-layer transform and wavelet packet three-layer energy decomposition, and a group of 8 wavelet packet energy parameters were established as frequency domain characteristic parameters. …”
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Spatial and Temporal Distribution Characteristics and Causes of Drought in Northwest China Based on SPEI by FENG Shiyuan, CHU Pinging, YAO Xin, YIN Dejun, GUO Yang

“…Based on monthly precipitation and average temperature data of 113 meteorological stations in Northwest China,through SPEI (standard precipitation evapotranspiration index),this paper analyzes and measures the drought process from 1960 to 2018,discusses the spatial and temporal variation characteristics of drought in Northwest China in recent 60 years combined with M-K test,univariate linear trend analysis and Arcgis software,and studies the drought correlation and periodic characteristics of summer monsoon,ENSO and MEI by using the methods of univariate linear analysis and cross wavelet to find out the causes of drought in Northwest China.The results show that:The multi-timescale SPEI could reflect the drought situation in Northwest China,and the drought intensity increases year by year;The seasonal drought in the study area is obvious,and the drought area increases with the year,especially after 2000s.The drought in eastern Xinjiang,Qinghai and northwest Gansu is extremely serious;SPEI summer drought index has a correlation with East Asian summer monsoon and plateau summer monsoon,and their impact on drought is opposite;The ENSO warm event has a great influence on the drought intensity and frequency before 2000,while after 2000,both ENSO warm and cold events have a great impact on that;The cross-wavelet and wavelet coherence images indicate that SPEI and MEI have similar oscillation period characteristics.There are four periods of high energy,and the resonance period range from 0 to 6 a,indicating that ENSO drives the drought with a period.…”
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PSYCHOACOUSTICALLY MOTIVATED TIME-FREQUENCY DICTIONARY BUILDING FOR UNIVERSAL SCALABLE AUDIOCODER BASED ON THE SPARSE APPROXIMATION by V. Y. Herasimovich, Al. A. Petrovsky

“…The article studies the process of creating a perceptually-motivated dictionary of the timefrequency functions based on the wavelet packet transform optimized for the input signal frame and its utilization in the universal scalable real-time audiocoder. …”
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A Robust VMD-Based Modified Multivariable Output Error Statespace Method for Detection of Low-Frequency Oscillations From Noisy Signals of WAMS by Dinesh Shetty, Nagesh Prabhu

“…The proposed system incorporates the wavelet based filter in conventional VMD which not only helps in fetching the frequency but also helps in filtering the noise with appropriate selection of the mother wavelet, i.e. it utilizes the fusion of VMD and Wavelet Transform. …”
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Simulation of Novel NEMS Contact Switch Using MRTD with Alterable Steps by Wen-Ge Yu, Kang-Qu Zhou, Zheng-Zhong Wu, Ting-Hong Yang, Jing Zhao

“…The major advantage of the MRTD algorithms is their capability to develop real-time time and space adaptive grids through the efficient thresholding of the wavelet coefficients. The error between the measured and computed results is below 5%, this indicated that the Haar-wavelet-based multiresolution time domain was suitable for simulating the nano-scaling contact switch.…”
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Peak-Based Mode Decomposition for Weak Fault Feature Enhancement and Detection of Rolling Element Bearing by Zhi Xu, Gang Tang, Mengfu He

“…But peak-based wavelet parameters need to be optimized due to the determined basis function and constant resolution, which will affect the efficiency of vibration signal analysis. …”
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Construction of Target Controllable Image Segmentation Model Based on Homotopy Perturbation Technology by Shu-Li Mei

“…Combining the multiscale wavelet interpolation operator and HPM, a semianalytical numerical method can be obtained, which can improve the computational efficiency and accuracy greatly. …”
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