Article
Environmental Sciences
Yi Lu, Hengchi Lei, Kuo Zhou, Lingkun Ran
Summary: This study uses high-precision microbarograph data and radar data to analyze the gravity fluctuation characteristics of four convective processes in the Beijing-Tianjin-Hebei region. The results show that convective cases are accompanied by gravity fluctuations of different time scales. The stronger the convective process, the larger the fluctuation amplitude. The study also found that the gravity wave characteristics can be separated from the background field through wavelet transform, with wave periods mainly concentrated in the range of 15-250 minutes.
Article
Biology
Ab Waheed Lone, Nizamettin Aydin
Summary: This paper investigates the classification of Doppler signals using the wavelet scattering transform algorithm to detect blood clots in the human body. The results show that this algorithm performs well on small datasets and achieves high accuracy and low prediction loss through support vector machine and Gaussian process regression.
COMPUTERS IN BIOLOGY AND MEDICINE
(2023)
Article
Engineering, Mechanical
Josue Pacheco-Cherrez, Arturo Delgado-Gutierrez, Diego Cardenas, Oliver Probst
Summary: The study introduces a novel approach based on wavelet transform for reliably detecting damage locations in structures in an experimental setup, with a 100% damage recognition rate demonstrated in the experiments.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2021)
Article
Engineering, Electrical & Electronic
Maximiliano Bueno-Lopez, Mauricio Sanabria-Villamizar, Marta Molinas, Efrain Bernal-Alzate
Summary: This paper presents a hybrid technique for analyzing oscillations in low voltage distribution systems with photovoltaic generation, and validates the results by comparing them with traditional methods, aiming to characterize the system behavior in the time-frequency domain.
ELECTRICAL ENGINEERING
(2021)
Article
Mathematics, Applied
Hari M. M. Srivastava, Firdous A. A. Shah, Huzaifa L. L. Qadri, Waseem Z. Z. Lone, Musadiq S. S. Gojree
Summary: The Hilbert transform, a widely used linear operator in filter design, signal processing, and communication theory, has limitations in representing signals in generalized domains. To overcome this, we propose a novel integral transform called the quadratic-phase Hilbert transform and study its fundamental properties, relationship with the quadratic-phase Fourier transform, convolution theorem, and the Bedrosian theorem. Simulation results confirm the validity and accuracy of our proposed transform.
Article
Engineering, Electrical & Electronic
Jun Shi, Gong Chen, Yanan Zhao, Ran Tao
Summary: The objective of this paper is to overcome the deficiency of the synchrosqueezed wavelet transform (SSWT) in dealing with signals with fast varying instantaneous frequencies by introducing the fractional wavelet transform (FRWT). A synchrosqueezed FRWT (SSFRWT) is proposed, which shares many properties with SSWT while offering new features. The theoretical analysis of SSFRWT, including derivation of its basic properties, is presented. The theoretical derivations are validated through simulations.
IEEE TRANSACTIONS ON SIGNAL PROCESSING
(2023)
Article
Chemistry, Analytical
Rims Janeliukstis, Deniss Mironovs
Summary: This study demonstrates that time-frequency methods can be used to identify modal parameters for structural health monitoring and the identified resonant frequencies and damping ratios can be used as features in a damage-detection scheme. The proposed damage indicator shows comparable accuracy to the Mahalanobis distance metric but is simpler to calculate and can capture the severity of damage.
Article
Geochemistry & Geophysics
V. Klausner, H. M. Gimenes, M. V. Cezarini, A. Ojeda-Gonzalez, A. Prestes, C. M. N. Candido, E. A. Kherani, T. Almeida
Summary: This article examines tsunamigenic variations in the geomagnetic field using four spatiotemporal methods, showing the potential for efficient retrieval of tsunami contributions. Studying the Maule (2010) tsunami event, it is found that tsunamigenic magnetic disturbances may originate from both ocean and atmospheric motion associated with tsunamis. Results suggest that various types of tsunamigenic disturbances can be identified well using the integrated analysis framework presented in this work.
PURE AND APPLIED GEOPHYSICS
(2021)
Article
Optics
Wentao Luo, Yu He, Yan Tang, Xiaolong Cheng
Summary: Spectrally resolved interferometry plays a crucial role in micro/nano-scale geometric measurement, and phase extraction is the key. The S-transform has advantages in phase extraction and has been proven to be feasible for measuring step heights.
Article
Engineering, Electrical & Electronic
Deyun Wei, Jun Yang
Summary: A novel estimation algorithm is proposed for non-uniform discrete Fourier transform (NUDFT) in this paper, which achieves compression of sparse signals and accurate detection of frequencies.
IEEE TRANSACTIONS ON SIGNAL PROCESSING
(2022)
Article
Engineering, Electrical & Electronic
S. Zurita-Zurita, Francisco J. Escribano, J. Saez-Landete, J. A. Rodriguez-Manfredi
Summary: This article analyzes the application of two alternative methods, DWT and HHT, to process temperature sensor measurements from the Mars Science Laboratory. The results show that the DWT method is more suitable for this application, providing better fitting for all realistic scenarios.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2021)
Article
Chemistry, Multidisciplinary
Shi Feng, John P. T. Mo
Summary: Nowadays, fault diagnostics are widely used in Industry 4.0, but they are mostly post-mortem. This paper compares several signal data processing techniques for predicting upcoming faults and finds that the continuous wavelet transform synchrosqueezed scalogram is the most suitable method. A new procedure is proposed to count the number of pulses in the synchrosqueezed scalogram, and a new method is developed to detect trends and predict fault occurrences.
APPLIED SCIENCES-BASEL
(2022)
Article
Engineering, Mechanical
Wei Zhou, Zhongren Feng, Y. F. Xu, Xiongjiang Wang, Hao Lv
Summary: A new signal decomposition method called empirical Fourier decomposition (EFD) is proposed to address the issues of mode mixing and inconsistency in existing methods. Numerical and experimental validations demonstrate that EFD can provide more accurate and consistent decomposition results for signals with multiple non-stationary modes and closely-spaced modes.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2022)
Article
Engineering, Mechanical
Hongya Qu, Tiantian Li, Ruilong Wang, Jianzhong Li, Zhongguo Guan, Genda Chen
Summary: This paper introduces adaptive wavelet analysis (AWT) as a preprocessing method to obtain a clearer, smoother, and more accurate time-frequency representation. Optimized analytical mode decomposition (AMD) is utilized for signal component extraction, successfully decomposing signals and performing system identification in a shake table test of a 1/20-scale cable-stayed bridge model.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2021)
Article
Engineering, Multidisciplinary
Sumika Chauhan, Manmohan Singh, Ashwani Kumar Aggarwal
Summary: A fault identification scheme for bearings is proposed in this paper, involving pre-processing vibration signals, extracting features, training SVM model, and optimizing SVM parameters for efficiency improvement. The efficacy of the proposed algorithm is verified with 100% accuracy.
Article
Engineering, Multidisciplinary
Xianwen Hu, Ching-Tai Ng, Andrei Kotousov
Summary: This study numerically and experimentally investigates the propagation of guided waves in a steel plate with one side partly exposed to water. The results demonstrate that the energy of the quasi-Scholte wave converted by the anti-symmetric Lamb wave decreases with increasing excitation frequency. It is also revealed that the guided wave energy can shift in the frequency domain if the phase velocity of the incident anti-symmetric Lamb wave is larger than the sound speed of water.
Article
Materials Science, Characterization & Testing
Juan Carlos Pineda Allen, Ching Tai Ng
Summary: The study investigates the detection of debonding at adhesive joints using a nonlinear Lamb wave mixing approach, and demonstrates the effectiveness of the presence of combined frequency wave for indicating debonding. The correlation between debonding width and combined harmonic energy generated due to debonding is found. The findings provide insights into debonding mechanisms at adhesive joints and can be used to further develop debonding detection techniques using wave mixing.
NDT & E INTERNATIONAL
(2022)
Article
Construction & Building Technology
Jinhang Wu, Ching Tai Ng, Han Fang
Summary: This paper assesses the capability of ultrasonic guided wave (GW) technique in detecting different sizes of internal damages in structural timber, and the robustness of the technique is demonstrated through experimental and numerical studies.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Mechanics
James Vidler, Andrei Kotousov, Ching-Tai Ng
Summary: This study provides a solution for determining the effective linear and nonlinear elastic properties of particulate composites subjected to finite elastic deformations. It involves weak nonlinearity to describe the behavior of engineering materials and composites under elastic loading, and derives a nonlinear analogue of the Eshelby solution for spherical particle deformation. The obtained theoretical results are consistent with known relationships for linear material properties and with limited experimental data.
INTERNATIONAL JOURNAL OF NON-LINEAR MECHANICS
(2022)
Article
Acoustics
Chang Jiang, Weibin Li, Mingxi Deng, Ching-Tai Ng
Summary: This paper investigates the generation of quasistatic pulses (QSPs) of guided waves propagation in fiber reinforced plastic (FRP) thin plates. Numerical analysis provides insights into the generation, propagation, and mode conversion of QSPs in composite materials. The results indicate that the displacement direction and generation efficiency of QSPs depend on various factors, including wave propagation direction, coefficients of the strain energy function, and the primary guided wave field. Comparisons and analyses reveal that the generated QSPs are either S0 mode or partly coupled S0 and SH0 modes with different in-plane displacements, regardless of the excitation of primary waves. The generation efficiency of QSPs is found to be influenced by both the mode types and primary guided wave propagation direction. Considering cumulative effect and divergence effect, it is found that appropriate excitation of primary guided waves can achieve higher efficiency of cumulative QSP generation compared to phase matched second harmonics.
JOURNAL OF SOUND AND VIBRATION
(2022)
Article
Instruments & Instrumentation
Chang Jiang, Changyu Zhang, Weibin Li, Mingxi Deng, Ching-Tai Ng
Summary: This study investigates the feasibility of using static component generation of guided waves for damage assessment of CFRP composite laminates. Numerical modeling and simulation are used to explore the features of the generated SC in composites. The study proposes a dynamic displacement measurement method based on piezoelectric transducers and validates it experimentally. The results demonstrate that the generated SC pulse of GW is an effective means to assess hygrothermal damage and low-velocity impact damage in CFRP composite plates.
SMART MATERIALS AND STRUCTURES
(2022)
Article
Mechanics
Yuan Feng, R. Muni Rami Reddy, Abdul Hamid Sheikh, Ching-Tai Ng, Scott T. Smith
Summary: The paper presents a new sub-laminate based higher-order laminated model for bending response of laminated composite and sandwich beams with and without delaminations. The model provides accuracy and versatility in modeling intact and delaminated multilayered beams.
COMPOSITE STRUCTURES
(2022)
Article
Engineering, Civil
Liujie Chen, Jiyang Fu, Yahui Mei, Di Huang, Ching-Tai Ng, Haodong Yao
Summary: This study investigates the characteristics of residual sequence from time series black box models, using Lagrange Multiplier (LM) test to evaluate its nonlinearity and non-stationarity. The study also proposes the use of permutation entropy to measure the complexity, randomness, and fluctuation of the residual sequence, establishing a correlation with structural abnormal response signal and safety state. The effects of operational variability, damage, and coupling disturbance on the residual-permutation entropy (R-PE) are analyzed in detail.
ENGINEERING STRUCTURES
(2022)
Article
Engineering, Civil
Alireza Ghiasi, Mahdi Kazemi Moghaddam, Ching-Tai Ng, Abdul Hamid Sheikh, Javen Qinfeng Shi
Summary: This paper proposes a practical vibration-based deep learning approach for damage classification in railway bridges. The approach uses vibration-based Convolutional Neural Networks (CNNs) to classify various extents of cross section losses due to damages like corrosion. The method is validated through field testing and simulated corrosion scenarios. The results show that the proposed method can achieve accurate damage classification close to 100%.
ENGINEERING STRUCTURES
(2022)
Article
Engineering, Multidisciplinary
Tingyuan Yin, Ching Tai Ng, James Vidler, Van Dac Ho, Andrei Kotousov
Summary: This study proposes an amplitude-modulation vibro-acoustic (AMVA) technique to track the evolution of thermal damage in pristine graphene mortar. The results show that the proposed AMVA technique is more sensitive and feasible to serve as the tool for thermal damage detection in cement-based material.
STRUCTURAL HEALTH MONITORING-AN INTERNATIONAL JOURNAL
(2023)
Article
Engineering, Civil
Xianwen Hu, Ching-Tai Ng, Andrei Kotousov
Summary: This study investigates the feasibility of using second harmonic generation to evaluate the material degradation of metallic plates with one side exposed to water through experimental and numerical simulations. The experimental results show that the second harmonics of leaky S-0 waves grow linearly with the propagation distance. The simulation results demonstrate that the values of the relative nonlinearity parameter change significantly with the material properties of the water-immersed plates in the initial stages of fatigue damage.
THIN-WALLED STRUCTURES
(2022)
Article
Acoustics
Hankai Zhu, Ching Tai Ng, Andrei Kotousov
Summary: This study evaluates fatigue damage based on the growth rate of combinational harmonics generated by mixing Lamb waves. The incorporation of the phase reversal approach improves the evaluation of harmonics and avoids the influence of unwanted harmonics. Results show that combinational harmonics are more sensitive to weak material nonlinearities compared to second harmonics. Experiments on damaged samples demonstrate that the sum of combinational harmonics has better sensitivity to progressive fatigue damage than second harmonics.
Article
Materials Science, Characterization & Testing
Hankai Zhu, Ching Tai Ng, Andrei Kotousov
Summary: Evaluation of fatigue damage using nonlinear guided wave mixing has been extensively studied. Combinational harmonics resulting from wave mixing of quasi-synchronized wave modes have attractive features and are sensitive to fatigue damage. However, limited research has been done on the frequency pair selection and time shifting of wave mixing signals. This study proposes a method and theoretical equations to guide the selection of wave mixing frequency pairs and introduces a new time shifting technique to enhance the generation of harmonics. These findings can further advance the development of damage detection methods using guided wave mixing.
NDT & E INTERNATIONAL
(2023)
Article
Neurosciences
Jinhang Wu, Chang Jiang, Han Fang, Ching-Tai Ng
Summary: This paper evaluates the feasibility of using the feature guided wave (FGW) technique to detect weld defects in steel T-welded joint structures. The Semi-Analytical Finite Element (SAFE) method is used to obtain modal solutions in the waveguide, and a new algorithm is developed to obtain FGW modes with high energy concentration and low attenuation. The study confirms the capability and robustness of the identified FGW mode (RTW) in detecting small weld defects.
Article
Acoustics
Hankai Zhu, Andrei Kotousov, Ching Tai Ng
Summary: This article proposes a quasi-fundamental antisymmetric mode of edge wave (QEA0) for evaluating defects on curved edges. Compared with the conventional guided waves and its symmetric counterpart (QES0), the QEA0 mode has a longer propagation distance and better defect sensitivity, allowing it to distinguish multiple defects and determine their locations. Therefore, the QEA0 mode shows great potential for non-destructive evaluation and structural health monitoring of structural edges with complex cross-sectional areas.
JOURNAL OF SOUND AND VIBRATION
(2023)
Article
Engineering, Civil
Renbing An, Jiacong Yuan, Yi Pan, Duhang Yi
Summary: Traditional timber structures built on sloped land are more susceptible to seismic damage compared to structures built on flat land. The upper portion of the structure is found to be the weak point on sloped land, with potential issues such as tenon failure and column foot sliding.
ENGINEERING STRUCTURES
(2024)
Article
Engineering, Civil
Elyas Bayat, Federica Tubino
Summary: The current design guidelines for assessing floor vibration performance do not consider the influence of variability in the walking path on the dynamic response of floors. This study investigates the dynamic response of floors under a single pedestrian walking load, taking into account the randomness of the walking path and load. The effectiveness of the current guidelines in predicting floor response is critically assessed.
ENGINEERING STRUCTURES
(2024)
Article
Engineering, Civil
Gao Ma, Chunxu Hou, Hyeon-Jong Hwang, Linghui Chen, Zhenhao Zhang
Summary: Minimizing earthquake damage and improving repair efficiency are the main principles of resilient structures. This study proposed a repairable column with UHPC segments and replaceable energy dissipaters. The test results showed that the columns with UHPC segments and replaceable dissipaters exhibited high strength, deformation capacity, and energy dissipation.
ENGINEERING STRUCTURES
(2024)
Article
Engineering, Civil
Kartheek S. M. Sonti, Pavan Kumar Penumakala, Suresh Kumar Reddy Narala, S. Vincent
Summary: In this study, the compressive behavior of alumina hollow particles reinforced aluminum matrix syntactic foams (AMSF) was investigated using analytical, numerical, and experimental methods. The results showed that the FE solver ABAQUS could accurately predict the elastic and elastio-plastic behavior of AMSFs. The study also suggested that FE models have great potential in developing new materials and composites under compression loading.
ENGINEERING STRUCTURES
(2024)
Article
Engineering, Civil
Zheqi Peng, Xin Wang, Zhishen Wu
Summary: In this study, the statistical modeling of fiber-reinforced polymer (FRP) cables using the classic fiber bundle model is explored. The study considers important features of large-scale multi-tendon FRP cables, such as initial random slack and uneven tensile deformation among tendons. A parametric study and reliability analysis are conducted to predict the load-displacement relation and design thousand-meter-scale FRP cables. The study emphasizes the relation between the reliability index beta of the cable and the safety factor gamma of the FRP material.
ENGINEERING STRUCTURES
(2024)
Article
Engineering, Civil
Yanchao Shi, Shaozeng Liu, Ye Hu, Zhong-Xian Li, Yang Ding
Summary: This paper introduces a damage assessment method for reinforced concrete (RC) columns under blast loading, using modal parameter measurement as the evaluation index. The validity of the proposed method is validated through numerical and experimental analysis. The results show that this modal-based damage assessment method is applicable for non-destructive evaluation of blast-induced damage of RC columns.
ENGINEERING STRUCTURES
(2024)
Article
Engineering, Civil
Xiaolin Zou, Maosheng Gong, Zhanxuan Zuo, Qifang Liu
Summary: This paper proposes an efficient framework for assessing the collapse capacity of structures in earthquake engineering. The framework is based on an accurate equivalent single-degree-of-freedom (ESDOF) system, calibrated by a meta-heuristic optimization method. The proposed framework has been validated through case studies, confirming its accuracy and efficiency.
ENGINEERING STRUCTURES
(2024)
Article
Engineering, Civil
Jie Hu, Weiping Wen, Chenyu Zhang, Changhai Zhai, Shunshun Pei, Zhenghui Wang
Summary: A deep learning-based rapid peak seismic response prediction model is proposed for the most common two-story and three-span subway stations. The model predicts the peak seismic responses of subway stations using a data-driven approach and limited information, achieving good predictive performance and generalization ability, and demonstrating significantly higher computational efficiency compared to numerical simulation methods.
ENGINEERING STRUCTURES
(2024)
Article
Engineering, Civil
Jin Ho Lee, Jeong-Rae Cho
Summary: A simplified model is proposed to estimate the earthquake responses of a rectangular liquid storage tank considering the fluid-structure interactions. The complex three-dimensional structural behavior of the tank is represented by a combination of fundamental modes of a rectangular-ring-shaped frame structure and a cantilever beam. The system's governing equation is derived, and earthquake responses such as deflection, hydrodynamic pressure, base shear, and overturning moment are obtained from the solution.
ENGINEERING STRUCTURES
(2024)
Article
Engineering, Civil
W. J. Lewis, J. M. Russell, T. Q. Li
Summary: The work discusses the key features and advantages of optimal 2-pin arches shaped by statistically prevalent load and constant axial stress. It extends the design space of symmetric arches to cover asymmetric forms and provides minimum values of constant stress for form-finding of such arches made of different materials. The analysis shows that constant stress arches exhibit minimal stress response and have potential implications for sustainability and durability of future infrastructure.
ENGINEERING STRUCTURES
(2024)
Article
Engineering, Civil
Wen-ming Zhang, Han-xu Zou, Jia-qi Chang, Tian-cheng Liu
Summary: Saddle position is crucial in the construction and control of suspension bridges. This study proposes an analytical approach to estimate the saddle positions in the completed bridge state and discusses the calculation under different definitions. The relationship between the saddle position and the tower's centerline is analyzed, along with the eccentric compression of the tower. The feasibility of the proposed method is verified through a real-life suspension bridge.
ENGINEERING STRUCTURES
(2024)
Article
Engineering, Civil
Shaise K. John, Alessio Cascardi, Yashida Nadir
Summary: This study experimentally investigated the use of TRM material for reinforcing concrete columns. The results showed that increasing the number of textile layers effectively increased the axial strength. Additionally, the choice of fiber type and hybrid textile configuration also had a significant impact on strength improvement. A new design model that considers the effects of both the confining matrix and textile was proposed.
ENGINEERING STRUCTURES
(2024)
Article
Engineering, Civil
Chandrashekhar Lakavath, S. Suriya Prakash
Summary: This study experimentally investigated the shear behavior of post-tensioned UHPFRC girders, considering factors such as prestress level, fiber volume fraction, and types of steel fibers. The results showed that increasing prestress and fiber dosage could enhance the ultimate load-carrying capacity of the girders, reduce crack angle, and increase shear cracking load.
ENGINEERING STRUCTURES
(2024)
Article
Engineering, Civil
Vahid Goodarzimehr, Siamak Talatahari, Saeed Shojaee, Amir H. Gandomi
Summary: In this paper, an Improved Marine Predators Algorithm (IMPA) is proposed for size and shape optimization of truss structures subject to natural frequency constraints. The results indicate that IMPA performs better in solving these nonlinear structural optimization problems compared to other state-of-the-art algorithms.
ENGINEERING STRUCTURES
(2024)
Article
Engineering, Civil
Chun-Xu Qu, Jin-Zhao Jiang, Ting-Hua Yi, Hong-Nan Li
Summary: In this paper, a computer vision-based method is proposed to monitor the deformation and displacement of building structures by obtaining 3D coordinates of surface feature points. The method can acquire a large number of 3D coordinates in a noncontact form, improve the flexibility and density of measurement point layout, and is simple and cost-effective to operate.
ENGINEERING STRUCTURES
(2024)
