Salt and Pepper Noise Removal with Noise Detection and a Patch-Based Sparse Representation by Di Guo, Xiaobo Qu, Xiaofeng Du, Keshou Wu, Xuhui Chen

“…Experiments are conducted for 30%∼90% impulse noise levels, and the simulation results demonstrate that the proposed method outperforms total variation and Wavelet in terms of preserving edges and structural similarity to the noise-free images.…”
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Surface-Enhanced Raman Spectroscopy for Monitoring Extravirgin Olive Oil Bioactive Components by C. Camerlingo, M. Portaccio, I. Delfino, M. Lepore

“…In this frame, we have investigated five noncommercial olive oils produced in different parts of South Italy by using a commercial Raman microspectroscopy apparatus and home-made signal-enhancing SERS substrates. A wavelet-based data analysis has allowed us to efficiently remove the background and the noise from the acquired spectra. …”
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Motor control method using single-sensor phase current reconstruction by Yin Lu, Yuntian Huang, Hao Guo

“…By collecting the motor's current signals and utilizing signal processing techniques such as Fourier transform and wavelet transform, information about the three-phase currents is extracted from the data of a single sensor. …”
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Machines’ Intelligent Fault Diagnosis Based on Hierarchical Refined Composite Generalized Multiscale Fluctuation Dispersion Entropy by Biwen Chen, Changsheng Chen, Zhenlai Ma, Guoping Li, Yi Zhang, Baoyue Li

“…Furthermore, low-frequency and high-frequency components of the data are comprehensively extracted using dual-tree complex wavelet packet transform (DTCWPT), and high-dimensional features are downscaled using t-distributed stochastic neighbor embedding (t-SNE) to obtain low-dimensional sensitive fault features. …”
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Analyzing Vibration Mechanism of Angular Contact Ball Bearing with Compound Faults on Inner and Outer Rings by Lihai Chen, Ma Fang, Ming Qiu, Yanfang Dong, Xiaoxu Pang, Junxing Li, Chuanmeng Yang

“…The signals of compound faults were decomposed by the dual-tree complex wavelet transform to identify their characteristic frequency. …”
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Research on Coal and Rock Type Recognition Based on Mechanical Vision by Qiang Zhang, Jieying Gu, Junming Liu

“…In order to identify different kinds of coal, rock, and gangue, the FPV integrated image transmission camera is used to collect images of 6 types of coal, 8 types of rocks, and 2 types of coal gangue, and the images are processed based on the two-dimensional discrete wavelet transform (2D-DWT) based on the steerable pyramid decomposition (SPD). …”
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Compressed Sensing Based Apple Image Measurement Matrix Selection by Ying Xiao, Wanlin Gao, Ganghong Zhang, Han Zhang

“…This paper firstly chooses sym5 wavelet base as apple image sparse transformation base, and then it uses Gaussian random matrices, Bernoulli random matrices, Partial Orthogonal random matrices, Partial Hadamard matrices, and Toeplitz matrices to measure apple images, respectively. …”
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Leaf Classification for Sustainable Agriculture and In-Depth Species Analysis by Sara Mumtaz, Shabbab Algamdi, Haifa F. Alhasson, Dina Abdulaziz Alhammadi, Ahmad Jalal, Hui Liu

“…We employ Scale Invariant feature transform (SIFT), wavelet transform, and particle gradient motion for feature extraction, followed by bee colony optimization to enhance the process. …”
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Can system dynamics explain long-term hydrological behaviors? The role of endogenous linking structure by X. Zhou, Z. Sheng, K. Manevski, K. Manevski, K. Manevski, R. Zhao, R. Zhao, Q. Zhang, Y. Yang, S. Han, J. Liu, J. Liu, Y. Yang, Y. Yang, Y. Yang

“…Using the headwaters of Baiyang Lake in China as a case study, the endogenous linking structure of the hydrological system was gradually unraveled from 1982 to 2015 through wavelet analysis, Granger's causality test, and a system dynamics model. …”
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Experimental Investigation of the Propagation and Attenuation Rule of Blasting Vibration Wave Parameters Based on the Damage Accumulation Effect by Huaibao Chu, Xiaolin Yang, Shuanjie Li, Weimin Liang

“…The blasting vibration wave was monitored on the surface of the specimens, and its energy was calculated by using the sym8 wavelet basis function. The experimental results showed that with the increase in the number of blasts, the damage continues to increase; however, the vibration velocity and the main frequency decrease continuously, the unfocused vibration wave energy in the zone near to the blasting source is rapidly concentrated in the low-frequency band (frequency bands 1 to 3), and the energy is further concentrated in the low-frequency band in the intermediate zone and zone far from the blasting source. …”
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Lamb Wave Directional Sensing with Piezoelectric Fiber Rosette in Structure Health Monitoring by Songlai Wang, Wanrong Wu, Yiping Shen, Hui Li, Binlong Tang

“…Experimental tests are conducted to demonstrate the directivity and the frequency response property of the piezoelectric fiber under different excitation central frequencies in comparison with the MFC, rectangular piezoelectric sheet, and circular piezoelectric disc. Continuous wavelet transform (CWT) is applied to extract the maximum response amplitude information of the acquired Lamb wave signal at a central frequency. …”
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Air Pollution Variation During COVID-19 Pandemic Using Satellite and On-site Measurement Data in Six Provinces in Iran by Maryam Zare Shahne, Amirhossein Noori, Mehdi Alizade Attar

“…The AOD distribution map and its trend illustrated that Guilan, Khorasan-Razavi, and Tabriz had become more pollutants after the outbreak due to changes in tourist patterns and emission inventories. Base on wavelet transform, implemented on ground-measurment of PM2.5, the PM2.5 concentration increased in early 2021 from the value in baseline period, due to eased restriction and expansion of public COVID-19 vaccine in all considered provinces.…”
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Translation Invariance-Based Deep Learning for Rotating Machinery Diagnosis by Wenliao Du, Shuangyuan Wang, Xiaoyun Gong, Hongchao Wang, Xingyan Yao, Michael Pecht

“…The autoencoder takes advantage of the multiscale normalized frequency spectrum information obtained by dual-tree complex wavelet transform as input. Accordingly, the multiscale normalized features guarantee the translational invariance for signal characteristics, and the stacked sparse autoencoder benefits the unsupervised feature learning and ensures accurate and stable diagnosis performance. …”
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A new -means singular value decomposition method based on self-adaptive matching pursuit and its application in fault diagnosis of rolling bearing weak fault by Hongchao Wang, Wenliao Du

“…Sparse decomposition has excellent adaptability and high flexibility in describing arbitrary complex signals based on redundant and over-complete dictionary, thus having the advantage of being free from the limitations of traditional signal processing methods such as wavelet and fast Fourier transform being imposed by orthogonal basis. …”
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An Efficient Image Compressor for Charge Coupled Devices Camera by Jin Li, Fei Xing, Zheng You

“…Recently, the discrete wavelet transforms- (DWT-) based compressor, such as JPEG2000 and CCSDS-IDC, is widely seen as the state of the art compression scheme for charge coupled devices (CCD) camera. …”
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Rolling Bearing Fault Diagnosis Based on Sensitive Feature Transfer Learning and Local Maximum Margin Criterion under Variable Working Condition by Shiyuan Liu, Xiao Yu, Xu Qian, Fei Dong

“…To enhance the performance of the fault diagnosis of bearings under different working conditions, a novel diagnosis framework inspired by feature extraction, transfer learning (TL), and feature dimensionality reduction is proposed in this work, and dual-tree complex wavelet packet transform (DTCWPT) is used for signal processing. …”
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TR Jets above Magnetic X-Type Null Points by Ehsan Tavabi, Mehri Heidari, Azam Mollatayefeh

“…We selected a high cadence sequence of SOT (Hinode) observations taken with both the HCaII and the Halpha filter to look at the details of the dynamics revealed by a significant jet event. Both wavelet and amplitude spectra analysis were used to analyze the observed kink wave and the time variations of intensities during the event. …”
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Study on Evaluation Theory of Bridge Damage State and Methodology on Early Warning of Danger by Guofu Jiang, Qianxue Liang, Hua Wang, Yucai Ju, Haihua Wang, Xirui Wang, Longlin Wang, Wensheng Wang

“…In order to solve the above problems, this paper proposes a novel evaluation and judgment theory of bridge damage state and methodology on early warning of danger. The wavelet packet analysis method is used to construct the observation equation and state equation of bridge systems, which could provide a relevant basis for evaluating the damage state of bridges. …”
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A Prediction Model of Structural Settlement Based on EMD-SVR-WNN by Xianglong Luo, Wenjuan Gan, Lixin Wang, Yonghong Chen, Xue Meng

“…Aiming at the problems in the structural deformation prediction model and considering the internal characteristics of deformation monitoring data and the influence of different components in the data on the prediction accuracy, a combined prediction model based on the Empirical Mode Decomposition, Support Vector Regression, and Wavelet Neural Network (EMD-SVR-WNN) is proposed. …”
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Laser Ultrasonic System for Surface Crack Visualization in Dissimilar Welds of Control Rod Drive Mechanism Assembly of Nuclear Power Plant by Yun-Shil Choi, Hyomi Jeong, Jung-Ryul Lee

“…Furthermore, ultrasonic spectral imaging unveiled frequency components of damage-induced waves, while wavelet-transformed ultrasonic propagation imaging enhanced damage visibility by generating a wave propagation video focused on the frequency component of the damage-induced waves. …”
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