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Dynamic responses of a piezoelectric semiconductor sandwich cylindrical shell covered with FGPS layers

International Journal of Mechanics and Materials in Design 2025年 1-21页

作者： Zhu, changsong Xu, Ziqi Liu, Jinxi State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang China

This paper focuses on the linear dynamic responses of a piezoelectric semiconductor (PS) sandwich cylindrical shell covered with functionally graded piezoelectric semiconductor (FGPS) layers. The PS sandwich cylindrical shell is composed of a PS core layer and two FGPS surface layers. The FGPS surface layer consists of the metal material (i.e., aluminum) and piezoelectric semiconductor material (i.e., zinc oxide). According to the virtual work, strain energy as well as kinetic energy of the FGPS sandwich cylindrical shell, the vibration governing differential equations are achieved on the basis of Hamilton’s principle. Then the theoretical solutions of the vibration responses are obtained by solving the governing equations with Navier method. Through numerical examples, the effect of the functionally graded index, thickness ratio, initial electron concentration and excitation frequency on the dynamic responses of the FGPS sandwich cylindrical shell is analyzed. The main novelty of the manuscript is that the induced electric potential, perturbation of electron concentration and radial displacement of the FGPS sandwich cylindrical shell may be regulated effectively by designing a proper initial electron concentration and applying an appropriate excitation frequency. The multi-field coupling mechanism among carrier, polarization as well as deformation is demonstrated. The current outcomes also show that the geometric parameter, circumference wave number and functionally graded index have a significant effect on the vibration frequency and damping characteristic of the FGPS sandwich cylindrical shell. © The Author(s), under exclusive licence to Springer Nature B.V. 2025.

关键词： Piezoelectric materials

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Dynamic analysis of asymmetric piecewise linear systems

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Applied Mathematics and Mechanics(English Edition) 2025年第4期46卷 633-646页

作者： Ruiliang ZHANG Yongjun SHEN Xiaotong YANG School of Mechanical Engineering Shijiazhuang Tiedao UniversityShijiazhuang050043China School of Traffic and Transportation Shijiazhuang Tiedao UniversityShijiazhuang050043China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang050043China

Piecewise linear systems are prevalent in engineering practice,and can be categorized into symmetric and asymmetric piecewise linear *** that symmetry is a special case of asymmetry,it is essential to investigate the broader model,namely the asymmetric piecewise linear *** traditional averaging method is frequently used for studying nonlinear systems,particularly symmetric piecewise linear systems,with the harmonic response of the oscillator serving as a key prerequisite for calculating steady-state ***,asymmetric systems inherently exhibit nonharmonic,asymmetric responses,rendering the traditional averaging method *** overcome this limitation,this paper introduces an improved averaging method tailored for an oscillator characterized by asymmetric gaps and *** the traditional method,which assumes a purely harmonic response,the improved averaging method redefines the system response as a superposition of a direct current(Dc)term and a first harmonic ***,the Dc term can be regarded as the offset induced by model ***,the Dc term is treated as a slow variable function of time,with its time derivative assumed to be zero when calculating the steady-state solution,akin to the amplitude and phase in the traditional averaging *** validation demonstrates that the responses computed in both time and frequency domains with the improved averaging method exhibit greater accuracy compared with those derived from the traditional *** these improved results,the study also examines the parameter effect,stability,and bifurcation phenomena within the amplitude-frequency responses.

关键词： nonlinear vibration piecewise linear system asymmetry averaging method offset

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Research on the application of the parameter freezing precise exponential integrator in vehicle-road coupling vibration

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Applied Mathematics and Mechanics(English Edition) 2025年第2期46卷 373-390页

作者： Yu ZHANG chao ZHANG Shaohua LI Shaopu YANG State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China Department of Engineering Mechanics Shijiazhuang Tiedao UniversityShijiazhuang 050043China Hebei Research Center of the Basic Discipline Engineering Mechanics Shijiazhuang Tiedao UniversityShijiazhuang 050043China

The vehicle-road coupling dynamics problem is a prominent issue in transportation,drawing significant attention in recent *** dynamic equations are characterized by high-dimensionality,coupling,and time-varying dynamics,making the exact solutions challenging to *** a result,numerical integration methods are typically ***,conventional methods often suffer from low computational *** address this,this paper explores the application of the parameter freezing precise exponential integrator to vehicle-road coupling *** model accounts for road roughness irregularities,incorporating all terms unrelated to the linear part into the algorithm's inhomogeneous *** general construction process of the algorithm is *** validity of numerical results is verified through approximate analytical solutions(AASs),and the advantages of this method over traditional numerical integration methods are *** parameter freezing precise exponential integrator schemes are constructed based on the Runge-Kutta framework,with the fourth-order four-stage scheme identified as the optimal *** study indicates that this method can quickly and accurately capture the dynamic system's vibration response,offering a new,efficient approach for numerical studies of high-dimensional vehicle-road coupling systems.

关键词： vehicle-road coupled dynamics dynamic response parameter freezing precise exponential integrator Newmark-βintegration

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IRT-diffusion: combined denoising diffusion probabilistic models with thermal signal processing methods for automated defect detection in composites using infrared thermography

IRT-diffusion: combined denoising diffusion probabilistic mo...

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2024 International conference on Optical and Photonic engineering, icOPEN 2024

作者： Wei, Yanjie Zhang, Yuhang Xiao, Yao Gu, Xiaohui State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang050043 China Department of Engineering Mechanics Shijiazhuang Tiedao University Shijiazhuang050043 China

ISBN: (数字)9781510688117

ISBN: (纸本)9781510688100

Infrared thermography (IRT) is a reliable method for detecting defects in composites with advantages of full field, non-contact, easy operation and good visualization. Nevertheless, interpretation by experts is required to distinguish between defective and sound regions in the practical evaluation of defects, which limits the industrial applications of infrared thermography. In this study, a denoising diffusion probabilistic model (DDPM) framework named IRT-Diffusion is proposed to automatically segment defective regions in thermal images. IRT-Diffusion can reconstruct a defect segmentation image from a noisy image with standard Gaussian distribution by iteratively performing multiple denoising operations. Detection results from various traditional thermal signal processing methods are employed as input for the conditional noise predictor of IRT-Diffusion to generate more accurate defect segmentation results. The core innovation of this study is that the state-of-the-art generative model is first introduced and designed for defect identification in composites using infrared thermography. To assess the performance of IRT-Diffusion, experiments were conducted on several composites panels and compared with conditional variational autoencoder (cVAE) and conditional generative adversarial network (cGAN). The results demonstrate that the proposed method achieves superior quantitative metrics and effectively extracts defective regions. © 2025 SPIE.

关键词： Image segmentation

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Determination of defect size for composites using derivative images in pulse thermography

Determination of defect size for composites using derivative...

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2024 International conference on Optical and Photonic engineering, icOPEN 2024

作者： Wei, Yanjie Lu, Jiashuo Xiao, Yao Gu, Xiaohui State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang050043 China Department of Engineering Mechanics Shijiazhuang Tiedao University Shijiazhuang050043 China

ISBN: (数字)9781510688117

ISBN: (纸本)9781510688100

Pulse thermography is a reliable method for detecting defects in composites with advantages of full field, non-contact and easy operation. However, the size determination of subsurface defects with low width-to-depth ratios using pulsed thermography is a challenging task due to the blurred defect edges in infrared thermal images caused by lateral heat diffusion. The present study explores the ability of time derivative images of infrared thermography to predict defect size. 2D thermal conduction of pulse thermography based on the virtual heat source method was analyzed to compare the temperature profile and derivative profile of defects along the diameter direction, and a size prediction method based on the derivative profile is proposed. The feasibility of the proposed method was evaluated by measuring the dimensions of the flat-bottomed holes in the composite panels. The experimental results demonstrated that the size inversion method based on derivative images brings an improvement in measuring accuracy for defects. Additionally, the influences of cooling time, defect depth, defect size and thermal properties of the material on the measurement of defect dimension are also discussed. © 2025 SPIE.

关键词： Thermography (imaging)

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Variable-length Genetic Algorithm based Blind Deconvolution for Railway Bearing Fault Diagnosis

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IEEE Sensors Journal 2025年

作者： Shi, Guangze Gu, Xiaohui Yang, Shaopu Li, Hefei Liu, Zechao Shijiazhuang Tiedao University State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang050043 China

Blind deconvolution (BD) methods have shown significant promise in machinery fault diagnosis, yet their performance remains constrained by fixed filter length and susceptibility to local optima. To tackle this problem, this paper presents a variable-length genetic algorithm (VGA) to optimize the blind filter for railway bearing fault diagnosis under complex interference. Unlike existing works, an attempt is made to determine the length and coefficients of the optimal blind filter in a general framework by introducing a cutting-splicing operator to replace the crossover to achieve chromosome length variation during the optimization iteration. Based on several popular BD approaches, including MED, McKD, MGID, and MESSD, their variable-length optimized version, i.e. VGA-MED, VGA-McKD, VGA-MGID, VGA-MESSD, are proposed and rigorously compared with the original version and the fix-length optimized version, i.e. GA-MED, GA-McKD, GA-MGID, GA-MESSD by both simulated and experimental railway bearing faulty signals. The results demonstrated the effectiveness and adaptability of the novel methods in recovering fault-induced repetitive transients. Furthermore, the adaptability and generalizability of the given framework make it a robust solution for BD-based fault diagnosis in industrial applications. © 2001-2012 IEEE.

关键词： Genetic algorithms

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Study on the Mechanism of Polygonal Wear in Wheels Based on Wheel-Rail contact Normal Force

Study on the Mechanism of Polygonal Wear in Wheels Based on ...

引用

International conference on Artificial Intelligence and Autonomous Transportation, AIAT 2024

作者： Zhou, Zichao Liu, Yongqiang Guo, Tao Wang, Tiecheng Huo, Wenbiao State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang050043 China School of Mechanical Engineering Shijiazhuang Tiedao University Shijiazhuang050043 China CRRC TANGSHAN CO. LTD. Tangshan063000 China

ISBN: (纸本)9789819639687

To address the issue of high-order polygonal wear in high-speed trains operating at 300 km/h, this paper investigates the influence of bogie modal vibration on the initiation and progression of such wear phenomena. The model simulation incorporates the modal vibrations of both the frame and the wheelset, while also accounting for non-Hertzian contact and track irregularity within a long-term iterative wear model, thereby enhancing its alignment with real-world operational conditions. The main conclusions are: The vibration frequency of the wheel-rail contact normal force, influenced by running speed and sleeper spacing, plays a key role in the initiation of polygonal wear. The fourth-order bending resonance of the wheelset is the primary cause of the 20th-order polygon wear and its rapid development. Suspension parameters have a significant impact on the wear index, and proper adjustment of these parameters can effectively slow the progression of polygonal wear. The findings of this paper hold theoretical value and practical significance in understanding the formation and progression mechanisms of polygonal wear, as well as in developing effective measures for its mitigation. © Beijing Paike culture commu. co., Ltd. 2025.

关键词： Railroads

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Analysis Method of Formation Mechanisms of Rail corrugations on Metro Lines

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Transportation Research Record 2025年

作者： Wang, Zhiqiang Lei, Zhenyu Luo, Yanyun Zhu, Jianyue State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang China Institute of Rail Transit Tongji University Shanghai China

To investigate generation causes of rail corrugation on metro lines, a new analysis method applicable to explain the formation mechanism of rail corrugation is proposed from micro creepage saturation and macro structural stability. The critical value of creepage saturation calculated by the micro determination program for creepage saturation of the wheel–rail system using dynamic methods can be used as the basis for judging the creepage saturation of the wheel–rail system, and when the composite creepage is greater than the critical value of creepage saturation, the wheel–rail creepage reaches saturation. The macro determination program for the structural stability of the wheel–rail system uses a complex modal method to judge the degree of system stability, which can consider the frequency domain characteristics of the system structure with material damping, so it is closer to the actual situation. The numerical results of creep characteristics of the wheel–rail system show that the occurrence section of initial corrugation is consistent with the actual situation of rail corrugation. The numerical results of the structural stability of the wheel–rail system show that frequencies and locations of unstable vibration modes are consistent with the measured rail corrugation. It can be concluded that it is feasible using the proposed analysis method to predict the formation of corrugations. combining the micro and macro determination programs, it can be concluded that the formation mechanism of the measured corrugation is that under the micro creepage saturation condition, the structural instability vibration at the specific frequency of the wheel–rail system causes rail corrugation. © The Author(s) 2025.

关键词： Subways

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Multi-Objective Parallel Human-machine Steering coordination control Strategy of Intelligent Vehicles Path Tracking Based on Deep Reinforcement Learning

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chinese Journal of mechanical engineering (English Edition) 2025年第1期38卷 1-19页

作者： Wang, Hongbo Feng, Lizhao Li, Shaohua chen, Wuwei Zhou, Juntao School of Automotive and Transportation Engineering Hefei University of Technology Hefei230009 China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang050043 China

In the parallel steering coordination control strategy for path tracking, it is difficult to match the current driver steering model using the fixed parameters with the actual driver, and the designed steering coordination control strategy under a single objective and simple conditions is difficult to adapt to the multi-dimensional state variables’ input. In this paper, we propose a deep reinforcement learning algorithm-based multi-objective parallel human-machine steering coordination strategy for path tracking considering driver misoperation and external disturbance. Firstly, the driver steering mathematical model is constructed based on the driver preview characteristics and steering delay response, and the driver characteristic parameters are fitted after collecting the actual driver driving data. Secondly, considering that the vehicle is susceptible to the influence of external disturbances during the driving process, the Tube MPc (Tube Model Predictive control) based path tracking steering controller is designed based on the vehicle system dynamics error model. After verifying that the driver steering model meets the driver steering operation characteristics, DQN (Deep Q-network), DDPG (Deep Deterministic Policy Gradient) and TD3 (Twin Delayed Deep Deterministic Policy Gradient) deep reinforcement learning algorithms are utilized to design a multi-objective parallel steering coordination strategy which satisfies the multi-dimensional state variables’ input of the vehicle. Finally, the tracking accuracy, lateral safety, human-machine conflict and driver steering load evaluation index are designed in different driver operation states and different road environments, and the performance of the parallel steering coordination control strategies with different deep reinforcement learning algorithms and fuzzy algorithms are compared by simulations and hardware in the loop experiments. The results show that the parallel steering collaborative strategy based on a deep

关键词： Deep reinforcement learning

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Analysis of Factors Affecting Vibration Response of Axle Box Bearing of High-Speed Trains

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Journal of Vibration engineering and Technologies 2025年第5期13卷 1-23页

作者： Wang, Min Yang, Shaopu Liu, Yongqiang chen, Yanhong Zhang, Kai State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang 050043 China School of Traffic and Transportation Shijiazhuang Tiedao University Shijiazhuang 050043 China School of Mechanical Engineering Shijiazhuang Tiedao University Shijiazhuang 050043 China CRRC TANGSHAN CO. LTD Tangshan 063000 China China Water Resources Beifang Investigation Design and Research Co. Ltd. Tianjin 300222 China

During the operation of high-speed trains, the vibration characteristics of axle box bearings are influenced by multiple factors. Specifically, this paper investigates the effects of track irregularity excitation, thermal deformation, and lubrication conditions on bearing vibration response under identical working conditions. To achieve this, based on Hertzian contact theory and elastohydrodynamic lubrication principles, a dynamic model of axle box bearing for high-speed train is established. Subsequently, the validity of the proposed model is verified by the experimental data of the single wheelset rolling vibration test bench. Furthermore, the typical fault forms of bearings are simulated, and consequently their effects on bearing vibration characteristics is analyzed. Moreover, the effects of fault size, rotational speed and bearing radial clearance on the system dynamic response are studied by using the eigenvalue of the covariance matrix and root mean square (RMS) value. The results show that track irregularity greatly increases bearing vibration, thermal deformation also causes bearing vibration to intensify. On the other hand, lubrication can effectively reduce bearing vibration. Additionally, the size and location of local bearing faults, along with rotational speed and radial clearance of bearings have great influence on the eigenvalue of the covariance matrix of bearing inner ring and outer ring. correspondingly, the RMS value of bearing vibration also varies significantly under different speeds. © Springer Nature Singapore Pte Ltd. 2025.

关键词： Bearing Lubrication Thermal deformation Track irregularity

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