Dynamic Responses of the Metro Train’s Bogie Frames: Field Tests and Data Analysis by Xuhui He, Kehui Yu, Chenzhi Cai, Yunfeng Zou

“…Then, the soft thresholding process and discrete wavelet transform decomposition process are conducted to obtain a denoised version of the original signals in the time-frequency domain. …”
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A New Transferable Fault Diagnosis Approach of Rotating Machinery Based on Deep Autoencoder and Dominant Features Selection under Different Operating Conditions by Fei Dong, Xiao Yu, Xinguo Shi, Ke Liu, Zhaoli Wu, Wanli Yu

“…First, maximal overlap discrete wavelet packet transform is applied for signals processing and mix-domains statistical feature extraction. …”
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Rural Acoustic Landscape Analysis Based on Segmentation and Extraction of Spectral Image Feature Information by Huijun Xiao, Tangsen Huang, Ensong Jiang

“…In this article, the Gabor wavelet filtering method is proposed to filter and analyze the spectral image. …”
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Research on the Estimation Model of Electrical Parameters of Silver-Based Contacts Based on Surface Morphology by Chao Wang, Xiancheng Wang, Chengjun Guo

“…Various original profile signals such as surface roughness, waviness, and surface form error are calculated using wavelet transformation, and a robust weight function is introduced to separate micro-textural features from macro-textural features. …”
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Identifying and Evaluating Chaotic Behavior in Hydro-Meteorological Processes by Soojun Kim, Yonsoo Kim, Jongso Lee, Hung Soo Kim

“…The time series in the period of approximately one year were extracted from the original series using the wavelet transform. The generated time series from summation of sine functions were fitted to each series and used for investigating the hypotheses. …”
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Study on Variation Law and Influencing Mechanism of Water and Sediment in Henan Reaches of the Yellow River by XUAN Xiaobo, DOU Ming, LIU Bojun

“…The Henan reaches of the Yellow River is a typical wandering reach, which has a severe impact on the river habitat due to the severe variation of water and sediment, frequent swing of the main channel, and serious deformation of the riverbed.Based on the water and sediment data of Xiaolangdi, Huayuankou, and Gaocun hydrological stations from 1960 to 2019, this paper explores the variation cycle characteristics of water and sediment in the Henan reaches of the Yellow River by using statistical methods such as Mann-Kendall test, sliding T test, and wavelet analysis.The contribution rate of rainfall and human activities to the decrease in runoff and sediment transport in the Henan reaches of the Yellow River is quantitatively evaluated by the double mass curve method.The results show that the decreasing trend of annual sediment transport is greater than that of annual runoff in the Henan reaches.From Xiaolangdi to Huayuankou, erosion and deposition are basically balanced, and from Huayuankou to Gaocun, deposition is dominant.The flood season in the Henan reaches is dominated by sediment deposition, and the non-flood season is dominated by scour.The sediment transport in Xiaolangdi station changed greatly in 1997, while the runoff and sediment transport in Huayuankou and Gaocun stations changed significantly in 1985.The water and sediment regulation greatly increases runoff instead of sediment transport.Human activities play a leading role in the decrease in runoff and sediment transport in the Henan reaches of the Yellow River, with an average contribution rate of 80.94% to runoff and 94.95% to sediment transport in the Henan reaches of the Yellow River.…”
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A Flexible UHF RFID Respiratory Sensor by Jéssyca I. L. Araujo, Georgina K. F. Serres, Simone Genovesi, Danilo F. S. Santos, Alexandre J. R. Serres

“…The RSSI data collected from the RFID tag readings were processed using the Daubechies wavelet of order 5 (db5) with three levels of signal decomposition, resulting in signals with reduced noise. …”
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Spatial and Temporal Characteristics of Precipitation and Runoff Response in Yalong River Basin by CHANG Xinyu, LIU Bin, JIA Yugong, FU Zhiyu

“…Under the dual influence of climate change and human activities,extreme climate occurs frequently around the world,and the precipitation in the studied basin has undergone profound changes,so it is necessary to further explore the inherent characteristics and variation laws of precipitation and runoff and thus enhance the understanding of the evolution laws of hydrological and meteorological elements in the basin under the changing environment.In this paper,Mann-Kendall nonparametric test,R/S analysis,moving t-test,and Morlet wavelet transform are introduced to analyze the interannual trend and identify abrupt changes and periodic characteristics of precipitation at meteorological stations in the Yalong River Basin in the past 50 years,and the response degree of runoff to precipitation is measured by correlation coefficient.The results show that the Hurst index of precipitation in the basin is greater than 0.5,and the precipitation trends at Qingshuihe,Shiqu,and Zhongdian stations are more significant;at the same time,due to the continuous influence of the changing environment,the precipitation in the basin has a multi-scale significant period in both time and frequency domains,and the precipitation fluctuates during small periods of 1.0~2.5 years and large periods of 4~6 years.Besides,the meteorological stations with strong runoff responses to precipitation in the basin are obtained,and the precipitation trend of other stations is not significant except Zhongdian station.The research results can provide a scientific basis for selecting driving factors of the nonlinear runoff forecasting model.…”
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Computational aerodynamics of insect flight using volume penalization by Engels, Thomas, Truong, Hung, Farge, Marie, Kolomenskiy, Dmitry, Schneider, Kai

“…Two open source codes, one based on Fourier, the other based on wavelet representation, are succinctly presented and a mass-spring flexible wing model is described. …”
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A bivariate multifractal analysis approach to understanding socio-spatial segregation dynamics by Janka Lengyel, Stéphane G. Roux, Olivier Bonin, Stéphane Jaffard, Patrice Abry

“…In this context, the proposed approach, which uses wavelet leaders for multifractal analysis of irregular point processes, estimates self-similarity and intermittency exponents as well as self-similar and multifractal cross-correlation by combining classical multifractal and geographic analysis methods. …”
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Fractional-order boundary value problems solutions using advanced numerical technique by Asmat Batool, Imran Talib, Muhammad Bilal Riaz

“…We provide a comprehensive comparison to demonstrate the accuracy and computational advantages of our proposed approach against existing methods, including the exact solution, the Haar wavelet method (HWM), the Bessel collocation method (BCM), the Pseudo Spectral Method (PSM), the Generalized Adams–Bashforth–Moulton Method (GABMM) and the fractional central difference scheme (FCDS) through numerical examples. …”
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A Self-Adaptive Frequency Decomposition Approach for Denoising to Enhance Data-Driven Learning of Cyclic Time Series in Medical Signal Estimation by Shang-Wei Chao, Feng-Li Lian

“…Through experimentation with different combinations of filtering methods and sequence-to-sequence deep learning models, our results demonstrate a 45% improvement in MSE over the Butterworth filter, 56% over the FIR filter, and 18% over the wavelet-based filter, confirming that self-adaptive decomposition filters offer superior performance for noisy cyclic time series in deep learning applications.…”
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Climate Change and Fruit-Picking Tourism: Impact and Adaptation by Jun Liu, Fan Chen, Quansheng Ge, Yunyun Li

“…In this paper, phenological data on the FMD for 45 types of plants in 1980–2012, dates for more than 200 fruit-picking festivals, and data on monthly average air temperature in 1980–2013 were used to assess the impact of CC on FPTA by wavelet and correlation analyses. The findings indicated that the study area had been significantly affected by CC. …”
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Dynamic Response and Its Frequency Domain Characteristics of Lateritic Soil Subgrade under Traffic Load during Construction by Wei Bai, Kun Mu, Lingwei Kong, Wenbo Zhang, Xiu Yue

“…The distribution law of the dynamic response and its frequency domain characteristics obtained by wavelet analysis emerged. The vibration of the subgrade is clearly aggravated by the increase of speed and load. …”
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Study on Spatio-temporal Variation Characteristics of Hydro-meteorological Factors in the Source Region of Yellow River by WANG Dong, WU Dongdong, JIE Xiaobai, LI Xuehui

“…In order to understand the variation characteristics of drought and flood in the sourceregion of Yellow River sufficiently, based on the hydro-meteorological data of the source regionof Yellow River from 1961 to 2016, this paper analyzes the trend, mutation and periodicity ofannual precipitation, annual average temperature and annual runoff by the the Mann-Kendall method,Pettitt test and Morlet wavelet analysis method, and studies the spatial variation characteristicsof annual precipitation and annual average temperature through the Kriging interpolation and spatialvariation coefficient. …”
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The Hybrid KICA-GDA-LSSVM Method Research on Rolling Bearing Fault Feature Extraction and Classification by Jiyong Li, Shunming Li, Xiaohong Chen, Lili Wang

“…A new method named sensitive subband feature set design (SSFD) based on wavelet packet is also presented; using proposed variance differential spectrum method, the sensitive subbands are selected. …”
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Automatic control technology of low frequency and low voltage splitting devices using wide area measurement information by Mingliang GAO, Bo ZHUANG, Xuefei NIU, Mouying LI

“…Aiming at the problems of large noise content of wide area measurement information of power grid and difficulty in controlling oscillation damping in interconnected areas of power grid, an automatic control technology of low frequency and low voltage splitting devices using wide area measurement information was proposed.Based on the wide area measurement system (WAMS), the wide area measurement information of the power grid during the operation was obtained.After the noise contained in the wide area measurement information of the power grid was removed by the wavelet decomposition de-noising method, the power grid low-frequency oscillation identification method based on Prony was used to identify the power grid oscillation region and oscillation value.Then, based on the grid oscillation region and oscillation value, the oscillation center voltage and positioning coefficient were calculated and used as input to design the automatic control flow of the low frequency and low voltage splitting device, so as to realize the automatic control of the low frequency and low voltage splitting device.The experimental results show that this method can effectively remove the noise contained in the wide area measurement information of the power grid, the maximum error of the oscillation damping value in the interconnected area of the power grid is only 0.01, and this method can effectively control the low frequency and low voltage splitting device.…”
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A parallel CNN architecture for sport activity recognition based on minimal movement data by Huipeng Zhao

“…In the subsequent phase, the signal characteristics are characterized using Discrete Wavelet Transform (DWT) and Short-Time Fourier Transform (STFT). …”
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A Hybrid Process Monitoring and Fault Diagnosis Approach for Chemical Plants by Lijie Guo, Jianxin Kang

“…Based on hazard and operability (HAZOP) analysis, kernel principal component analysis (KPCA), wavelet neural network (WNN), and fault tree analysis (FTA), a hybrid process monitoring and fault diagnosis approach is proposed in this study. …”
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Market Power, NAIRU, and the Phillips Curve by Derek Zweig

“…We find weak evidence supporting the NAIRU theory from the simplistic model, but stronger evidence using BVAR. A wavelet analysis reveals that the short-run NAIRU theory and Phillips curve relationships may be time-dependent, while the long-run relationships are essentially vertical, suggesting instead that each relationship is primarily observed over the medium-term (2-10 years), though the economically significant medium-term region has narrowed in recent decades to roughly 4-7 years. …”
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