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Nonlinear free vibration of piezoelectric semiconductor doubly-curved shells based on nonlinear drift-diffusion model

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Applied Mathematics and Mechanics(English Edition) 2023年第10期44卷 1761-1776页

作者： changsong ZHU Xueqian FANG Jinxi LIU State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China Key Laboratory of Mechanical Behavior Evolution and Control of Traffic Engineering Structures in Hebei Shijiazhuang 050043China School of Environment and Civil Engineering Dongguan University of TechnologyDongguan 523808Guangdong ProvinceChina

In this paper, the nonlinear free vibration behaviors of the piezoelectric semiconductor(PS) doubly-curved shell resting on the Pasternak foundation are studied within the framework of the nonlinear drift-diffusion(NLDD) model and the first-order shear deformation theory. The nonlinear constitutive relations are presented, and the strain energy, kinetic energy, and virtual work of the PS doubly-curved shell are *** on Hamilton's principle as well as the condition of charge continuity, the nonlinear governing equations are achieved, and then these equations are solved by means of an efficient iteration method. Several numerical examples are given to show the effect of the nonlinear drift current, elastic foundation parameters as well as geometric parameters on the nonlinear vibration frequency, and the damping characteristic of the PS doublycurved shell. The main innovations of the manuscript are that the difference between the linearized drift-diffusion(LDD) model and the NLDD model is revealed, and an effective method is proposed to select a proper initial electron concentration for the LDD model.

关键词： nonlinear free vibration piezoelectric semiconductor(PS)doubly-curved shell nonlinear drift-diffusion(NLDD)model linearized drift-diffusion(LDD)model

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A mechanism-data dual-driven approach for predicting profile changes in rails

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Wear 2025年 578-579卷

作者： Yadi Yang Jianxi Wang Yang Li Wenjie An Jiasheng cai Key Laboratory of Roads and Railway Engineering Safety Control Ministry of Education Shijiazhuang Tiedao University Shijiazhuang 050043 PR China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang 050043 PR China

Accurate prediction of rail profile changes is crucial for scientifically formulating rail wear mitigation strategies, maintaining track reliability, and ensuring economic benefit. However, traditional models based on rail wear mechanisms are limited in prediction accuracy due to their idealized assumptions. While possessing strong nonlinear fitting capabilities, data-driven models often lack interpretability and rely on large amounts of high-quality training data. To address these challenges, this paper proposes a novel method that integrates the advantages of both approaches to predict rail profile changes. Utilizing a prototype network, a rail profile change model is pre-trained with simulation data and then fine-tuned using measurement rail profile data through transfer learning. K-fold cross-validation and noise augmentation are employed to enhance the model's prediction accuracy and robustness. The study results indicate that for tracks with curve radii between 400 and 600 m, the precision of 10 random prediction trials exceeds 90 %, with standard deviations of Mean Squared Error ( MSE ), Root Mean Squared Error ( RMSE ), Mean Absolute Error ( MAE ), and Mean Absolute Percentage Error ( MAPE ) being 0.03397 mm 2 , 0.04261 mm, 0.0204 mm, and 0.175 %, respectively, demonstrating excellent predictive accuracy and stability. compared to models using only measurement data, this method achieves reductions in average MSE , RMSE , MAE , and MAPE by 30.60 %, 11.76 %, 12.94 %, and 10.45 %, respectively.

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Defect Analysis and Innovation Design of Synchronizer for clutchless Automatic mechanical Transmission

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chinese Journal of mechanical engineering 2022年第1期35卷 238-254页

作者： Lipeng Zhang Yunao Peng Haojie Yang Shaohua Li Hebei Key Laboratory of Special Delivery Equipment Yanshan UniversityQinhuangdao 066004China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China

The synchronizer is a key component of automatic mechanical transmission(AMT)equipped in electric vehicles,but the inertial lock-ring synchronizer(ILRS)commonly used there is not suitable especially for pure electric vehicles without a clutch because of big shift *** make the shifting process rapid and smooth,a new synchronizer named pressure-controllable friction ring synchronizer(PcFRS)was ***,the inevitable shortcoming of ILRS was verified by simulation and ***,the mechanical characteristics and advantages of the new synchronizer over ILRS were ***,the formulations describing the dynamic transmission based on the working mechanism of the PcFRS were ***,the shifting simulation results with PcFRS and ILRS based on the same operating conditions were compared and *** research shows that the PcFRS can meet the main shifting evaluation index of an AMT without complex control methods,as well as it takes only 0.2406 s to finish the comfortable and zero-speed-difference *** shifting quality of PcFRS is better than that of the *** lays a foundation for using the new synchronizer as a part of clutchless AMTs equipped in pure electric vehicles.

关键词： Electric vehicle clutchless automatic mechanical transmission Inertial lock-ring synchronizer Pressure-controllable friction ring synchronizer mechanical characteristics Shifting quality

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A crystal-Plasticity cyclic constitutive Model for the Ratchetting of Polycrystalline Material considering Dislocation Substructures

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Acta Mechanica Solida Sinica 2020年第2期33卷 268-280页

作者： Xuehong Ren Shaopu Yang Guilin Wen Wenjie Zhao State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan UniversityChangsha 410082China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China

A crystal-plasticity cyclic constitutive model of polycrystalline material considering intra-granular heterogeneous dislocation substructures,in terms of three dislocation categories:mobile dislocations,immobile dislocations in the cell interiors and in the cell walls,is proposed based on the existing microscopic and macroscopic experimental *** multiplication,annihilation,rearrangement and immobilization of dislocations on each slip system are taken as the basic evolutionary mechanism of the three dislocation categories,and the cross-slip of screw dislocations is viewed as the dynamic recovery mechanism at room *** slip resistance associated with the isotropic hardening rule results from the interactions of dislocations on the slip ***,a modified nonlinear kinematic hardening rule and a rate-dependent flow rule at the slip system level are employed to improve the predictive capability of the model for ratchetting *** predictive ability of the developed model to uniaxial and mul-tiaxial ratchetting in macroscopic scale is verified by comparing with the experimental results of polycrystalline 316L stainless *** ratchetting in intra-granular scale which is obviously dependent on the crystallographic orientation and stress levels can be reasonably predicted by the proposed model.

关键词： Ratchetting Dislocation substructures crystal plasticity Polycrystalline materials constitutive model

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Propagation of Rayleigh-type surface waves in a layered piezoelectric nanostructure with surface effects

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Applied Mathematics and Mechanics(English Edition) 2022年第3期43卷 327-340页

作者： Lele ZHANG Jing ZHAO Guoquan NIE Jinxi LIU State Key Laboratory of Mechanical Behavior and System Safety of Tra±c Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China Hebei Key Laboratory of Mechanics of Intelligent Materials and Structures Department of Engineering MechanicsShijiazhuang Tiedao UniversityShijiazhuang 050043China Department of Architecture Shijiazhuang Institute of Railway TechnologyShijiazhuang 050041China

This work investigates the dispersion properties of Rayleigh-type surface waves propagating in a layered piezoelectric nanostructure composed of a piezoelectric nanofilm over an elastic *** one of the most important features of nanostructures,surface effects characterized by surface stresses and surface electric displacements are taken into account through the surface piezoelectricity theory and the nonclassical mechanical and electrical boundary *** expressions of the dispersion equation are derived,and numerical results are provided to examine the effects of several surface-related parameters,including the surface elasticity,surface piezoelectricity,surface dielectricity,surface density,as well as surface residual stress,on the dispersion modes and phase *** size-dependent dispersion behaviors occurring with surface effects are also predicted,and they may vanish once the thickness of the piezoelectric nanofilm reaches a critical value.

关键词： surface effect surface piezoelectricity dispersion behavior piezoelectric nanofilm Rayleigh wave

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Integrated Active Suspension and Anti-Lock Braking control for Four-Wheel-Independent-Drive Electric Vehicles

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chinese Journal of mechanical engineering 2024年第1期37卷 87-98页

作者： Ze Zhao Lei Zhang Xiaoling Ding Zhiqiang Zhang Shaohua Li Liang Gu National Engineering Research Center for Electric Vehicles Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China

This paper presents an integrated control scheme for enhancing the ride comfort and handling performance of a four-wheel-independent-drive electric vehicle through the coordination of active suspension system(ASS)and anti-lock braking system(ABS).First,a longitudinal-vertical coupled vehicle dynamics model is established by integrating a road input *** the coupling mechanisms between longitudinal and vertical vehicle dynamics are *** ASS-ABS integrated control system is proposed,utilizing an H∞controller for ASS to optimize load transfer effect and a neural network sliding mode control for ABS ***,the effectiveness of the proposed control scheme is evaluated through comprehensive tests conducted on a hardware-in-loop(HIL)test *** HIL test results demonstrate that the proposed control scheme can significantly improve the braking performance and ride comfort compared to conventional ABS control methods.

关键词： Four-wheel-independent-drive electric vehicles Active suspension system(ASS) Anti-lock braking system(ABS) Vertical-longitudinal vehicle dynamics

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Gas control technology for coal and gas outburst mines based on new sealing materials

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Geohazard Mechanics 2024年第3期2卷 181-188页

作者： Hongwei Zhang Hongbao Zhao Dongliang Ji Shijie Jing Yuxuan Guo School of Energy and Mining Engineering China University of Mining and Technology(Beijing)Beijing100083China State Key Laboratory of Mechanical Behavior and System Safety of Trafﬁc Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang050043China

In order to solve the problem of gas overlimit in corner corners of coal and gas prominent mines, through thecombination of air leakage mechanism in the goaf, near-ﬁeld ﬁssure expansion and rich area division, blockingmaterial development and optimization, performance measurement of blocking materials and on-site test, westarted to study the causes of gas concentration in corner corners, analysis of roof collapse and transparency incorners and performance test of blocking materials, and optimized the blocking materials by combining laboratory test and engineering test. considering the thickness of the sealing ﬁlm, the attenuation ratio of the sealingﬁlm thickness, the gelation time, and the gelation viscosity under different ratios, we designed a multi factororthogonal experiment to optimize the optimal ratio suitable for the engineering site. Factors affecting blockingeffectiveness, such as gel water retention and gel ﬂame resistance, were also tested. The sealing scheme wasimplemented in the 2109 working face of a coal and gas outburst mine in Gansu, china. Through on-sitemonitoring of the changes in temperature, gas concentration, and air leakage at each monitoring point beforeand after the use of sealing materials, the analysis of the detection results shows that the temperature changes ateach monitoring point after the use of sealing materials do not exceed 0.2c;The change in oxygen concentrationis less than 0.27 %;The gas concentration has decreased by more than 60 %, with a decrease of 71.32 % in the gasconcentration in the upper corner. The air leakage has decreased by more than 53 %, and the proportion ofdecrease in air leakage at the upper corner is as high as 56.83 %. This air leakage control technology hasremarkable blocking effect, meets the requirements of corner near-ﬁeld ﬁssure blocking material, and is easy toprepare, inexpensive, non-toxic, tasteless and green, providing a successful experience for the treatment of similarcoal and gas outburst min

关键词： coal and gas outburst Air leakage in goaf Near-ﬁeldﬁssure Gas concentration Air leakage

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High-speed rail roller bearings with built-in triboelectric sensors

Cell Reports Physical Science

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cell Reports Physical Science 2025年第5期6卷

作者： Li, Shuai Gao, Shuai Wang, Song Gu, Xiaohui Liu, Yongqiang Zhang, Xiantao Hu, Jian Pennacchi, Paolo Pu, Huayan Luo, Jun chu, Fulei Han, Qinkai State Key Laboratory of Mechanical Transmission for Advanced Equipment Chongqing University Chongqing 400044 China State Key Laboratory of Tribology Department of Mechanical Engineering Tsinghua University Beijing 100084 China State Key Laboratory of Mechanical Behavior and System Safety of Train Engineering Structures Shijiazhuang Tiedao University Shijiazhuang 050043 China Department of Mechanical Engineering Politecnico Di Milano Via G. La Masa 1 Milan 20156 Italy

To dynamically monitor roller bearings in high-speed trains and computationally predict their fluid dynamics with high precision, this study proposes a built-in, compact, and integrated triboelectric cage speed sensor for double-row tapered roller bearings (TcSS-DTRBs). The design is based on a dual-sided electrode located in the internal space and two polytetrafluoroethylene dielectric layers that rotate synchronously with both cages, forming two freestanding-mode triboelectric nanogenerators that detect motion on both cage sides. Experiments on a full-scale train roller bearing are conducted under two types of lubricating scenarios. The stability and applicability of the monitoring function are validated using two different scale test rigs. Furthermore, setting the skidding results of the TcSS as boundary conditions, a FLUENT model of the DTRB is established to achieve high-precision computational fluid dynamics predictions. The combination of TcSS and fluid dynamics analysis provides a solid foundation for the intelligent design of train roller bearings. © 2025 The Author(s)

关键词： double-row tapered roller bearings fluid dynamics skidding triboelectric nanogenerators triboelectric sensor

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Love Waves in a Piezoelectric Semiconductor Thin Film on an Elastic Dielectric Half-Space

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固体力学学报（英文版） 2023年第1期36卷 45-54页

作者： Ru Tian Guoquan Nie Jinxi Liu Ernian Pan Yuesheng Wang State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China Department of Mathematics and Physics Shijiazhuang Tiedao UniversityShijiazhuang 050043China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China School of Mechanical Engineering Shijiazhuang Tiedao UniversityShijiazhuang 050043China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China College of Engineering and Institute of Pioneer Semiconductor Innovation National Yang Ming Chiao Tung UniversityTaiwanChina Department of Mechanics Beijing Jiaotong UniversityBeijing 100044China

In this paper,Love waves propagating in a piezoelectric semiconductor(PSc)layered structure are investigated,where a PSc thin film is perfectly bonded on an elastic dielectric *** dispersion equations are derived *** influence of semiconducting properties on the propagation characteristics is examined in *** results show that the semiconducting effect reduces the propagation speed,and that the Love waves can propagate with a speed slightly higher than the shear wave speed of the elastic dielectric *** wave speed and attenuation significantly depend on the steady-state carrier density and the thickness of the PSc thin *** is also found that when the horizontal biasing electric field is larger than the critical value(corresponding to the zero attenuation),the wave amplitude is *** findings are useful for the analysis and design of various surface wave devices made of PSc.

关键词： Love wave Piezoelectric semiconductor Layered structure Dispersion Attenuation

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Mesoscale Damage Analysis of UHTcc under Seawater Dry-Wet cycles Using Particle Flow Theory

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Mechanics Research communications 2025年

作者： Ruiqing chang Zhanyou Yan Li Zhao Shuo Xu Xiya Zhao Yiqing Yan School of Traffic and Transportation Shijiazhuang Tiedao University Hebei China School of Civil Engineering Shijiazhuang Tiedao University Hebei China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Hebei China

This study investigates the effects of seawater dry-wet cycling on the dynamic compressive properties of Ultra-High Toughness cementitious composites (UHTcc) using a discrete element model developed with Particle Flow code (PFc2D). Five sets of controlled laboratory dynamic compression tests with varying dry-wet cycles were conducted alongside numerical simulations to examine force chain evolution, crack propagation, and acoustic emission characteristics at the mesoscale level. Results demonstrate good agreement between numerical simulations and experimental data. The peak stress of UHTcc exhibited a non-monotonic response to increasing dry-wet cycles, initially rising before declining after reaching its maximum at 90 days. Acoustic emission events showed strong correlation with crack development, where increased crack density corresponded to higher signal intensity and event frequency. The developed discrete element model successfully captured the complete internal fracture process at microscopic scales, demonstrating its effectiveness for analyzing complex mechanical behaviors in cementitious composites.

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