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Defence Technology（防务技术） 2022年第2期18卷 183-193页

作者： Yu-xing Li Shang-bin Jiao Bo Geng Qing Zhang You-min Zhang School of Automation and Information Engineering Xi’an University of TechnologyXi’an710048China Shaanxi Key Laboratory of Complex System Control and Intelligent Information Processing Xi’an University of TechnologyXi’an710048China Department of Mechanical Industrial and Aerospace EngineeringConcordia UniversityMontrealQuebec H3G 1M8Canada

Refined composite multi-scale dispersion entropy(RCMDE),as a new and effective nonlinear dynamic method,has been applied in the field of medical diagnosis and fault diagnosis.In this paper,we first introduce RCMDE into the field of underwater acoustic signal processing for complexity feature extraction of ship radiated noise,and then propose a novel classification method for ship-radiated noise based on RCMDE and k-nearest neighbor(KNN),termed RCMDE-KNN.The results of a comparative experiment show that the proposed RCMDE-KNN classification method can effectively extract the complexity features of ship-radiated noise,and has better classification performance under one and two scales than the other three classification methods based on multi-scale permutation entropy(MPE)and KNN,multi-scale weighted-permutation entropy(MW-PE)and KNN,and multi-scale dispersion entropy(MDE)and KNN,termed MPE-KNN,MW-PE-KNN,and MDE-KNN.It is proved that the RCMDE-KNN classification method for ship-radiated noise is feasible and effective,and can obtain a very high recognition rate.

关键词： nonlinear dynamic Refined composite multi-scale dispersion entropy(RCMDE) Multi-scale dispersion entropy(MDE) Multi-scale weighted-permutation entropy (MW-PE) Multi-scale permutation entropy(MPE) Classification of ship-radiated noise

nonlinear dynamic Modeling for Joint Interfaces by Combining Equivalent Linear Mechanics with Multi-objective Optimization

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Acta Mechanica Solida Sinica 2020年第4期33卷 564-578页

作者： Dong Wang Xuanliua Fan Institute of Systems Engineering China Academy of Engineering PhysicsMianyang 621099China Shock and Vibration of Engineering Materials and Structures Key Laboratory of Sichuan Province Mianyang 621999China

The nonlinear dynamic modeling by combining the equivalent linear mechanics with the multi-objective optimization algorithm is proposed to describe the nonlinear behaviors of the joint interfaces.The joint interfaces are simplified as the equivalent virtual material or linear spring damper element.The genetic algorithm for multi-objective optimization is then used to identify the mechanical properties of the equivalent joint by minimizing the error between the simulated dynamic characteristics and the experimental results,including the modal frequencies of the bolted joint beam and the frequency response functions(FRFs)of the rubber isolation system.The FRFs are divided into several subsections with frequency-varied dynamic properties of the joint to consider the nonlinear dynamic behaviors,and the effects of subsection number and excitation amplitudes on the FRFs are also investigated.The results show that the simulated dynamic characteristics of modal frequencies and FRFs agree well with the experimental results.With the increase in the subsection number,the simulated FRFs agree better with the experimental results,indicating a good performance of modeling the nonlinear dynamic behaviors of the joint interfaces forced by different excitation amplitudes.Larger excitation amplitudes will decrease the joint stiffness.

关键词： Joint interfaces nonlinear dynamic Equivalent linear mechanics Frequencyvaried properties Multi-objective optimization

nonlinear dynamic Analysis of Flexible Marine-Risers

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China Ocean Engineering 1991年第4期6卷 373-384页

作者： Chen Jiajing and Wang Dongjiao Professor, South China University of Technology, Guangzhou PhD Student, Hong Kong Polytechnic Formerly, South China University of Technology, Guangzhou

A nonlinear dynamic analysis model is estabilished on the basis of 'lumped mass' approach, which takes the influence of the fluid flow within the pipe into consideration. Numerical results are compared with the published works, and the effects of internal fluid flow, internal pressure, dyanmics as well as the nonlinear characteristics on the behavior of flexible risers are discussed. From this work, some useful conclusions are drawn.

关键词： flexible riser nonlinear dynamic analysis model irregular wave oilfield exploitation

nonlinear dynamic and Effect Parameters Analysis for Extension Pneumatic Muscle

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Nonlinear Dynamic and Effect Parameters Analysis for Extensi...

Geometrically nonlinear inerter for vibration suppression

第30届中国控制与决策会议

作者： Zhiyuan Zhang Xueqian Wang Houde Liu Songtao Wang Bin Liang Tsinghua University National Laboratory for Information Science and Technology Tsinghua University Graduate School at Shenzhen Research Institute of Tsinghua University in Shenzhen

To realize high precision servo control for the extension pneumatic muscle（E-PM）, the nonlinear dynamic model of the E-PM is established and the effect parameters of the nonlinear dynamic model are analyzed, according to the phenomenological dynamic modeling theory. Firstly, an E-PM is designed based on the basic principle of PMs. Secondly, based on the dynamic characteristics of the E-PM, the nonlinear dynamic model of the E-PM is established. Thirdly, the parameters of the nonlinear dynamic model are identified by the elasticity test. Lastly, in the Matlab\Simscape environment, the nonlinear dynamic model of the E-PM is simulated and the effect parameters of the nonlinear dynamic model are analyzed. The result shows that the nonlinear dynamic model by phenomenological dynamic modeling theory can accurately reflect the dynamic characteristics of the E-PM. In addition, when the damping parameter changes in the range of 0.35-0.55, the biggest difference between the rise time is 1.5 s and the biggest difference between the stable time is 3.1 s. It indicates that the damping parameter has a great effect on the dynamic characteristics of the E-PM.

关键词： E-PM nonlinear dynamic Phenomenological Modeling Theory

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Applied Mathematics and Mechanics(English Edition) 2023年第11期44卷 1871-1886页

作者： Yuyang SONG Liqun CHEN Tianzhi YANG School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China Shanghai Institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy EngineeringShanghai Frontier Science Center of MechanoinformaticsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200444China

A two-degree-of-freedom(2DOF)vibration isolation structure with an integrated geometric nonlinear inerter(NI)device is proposed.The device is integrated into an inertial nonlinear energy sink(INES),and its vibration suppression performance is examined by the Runge-Kutta(RK)method and verified by the harmonic balance method(HBM).The new isolator is compared with a traditional vibration isolator.The results show a significant improvement in the vibration suppression performance.To investigate the effects of the excitation amplitude and initial condition on the dynamics of the system,a series of transmissibility-frequency response analyses are performed based on the displacement transmissibility.The energy flow of the system is analyzed,and numerous calculations reveal a series of ideal values for the energy sink in the NI-INES system.This study provides new insights for the design of vibration isolators.

关键词： inerter nonlinear dynamic isolator energy

Study on nonlinear dynamic Characteristics of Wheel Shimmy of 4WID Electric Vehicle with nonlinear Damping and Stiffness

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Study on Nonlinear Dynamic Characteristics of Wheel Shimmy o...

Deflection amplification factor for estimating seismic lateral deformations of RC frames

第30届中国控制与决策会议

作者： Gang Li Nan Chen Vehicle Engineering Laboratory School of Mechanical Engineering Southeast University

The development of four-wheel independent drive（4 WID） electric vehicles（EVs） has led to significant changes in modern vehicles. The introduction of an in-wheel motor（IWM）, which increases the unsprung mass of the vehicle, deteriorates the comfort and the contact condition between tires and road. Besides, it also increases the coupling effect of the vertical vibration of the suspension and the shimmy of the steering system. In this paper, a dynamics model of the wheel shimmy with 5 DOFs is established base on Lagrange’s equation. The tire model uses a nonlinear magic formula, taking into account the nonlinear suspension system. Based on the bifurcation theory in nonlinear dynamics, the influence of the characteristics of the nonlinear suspension system on the limit cycle in the self-excited shimmy is analyzed systematically and its numerical characteristics are analyzed. The results show that the nonlinear suspension have contribution to the dynamic phenomenon of the wheel shimmy system. It provides a new theoretical basis for the nonlinear suppression and control of wheel shimmy of 4 WID EVs.

关键词： Wheel Shimmy 4WID nonlinear Suspension nonlinear dynamic

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Earthquake Engineering and Engineering Vibration 2015年第2期14卷 373-384页

作者： Maryam Samimifar Asghar Vatani Oskouei Fayaz Rahimzadeh Rofooei Department of Civil Engineering Shahid Rajaee Teacher Training University Department of Civil Engineering Kharazmi University Department of Civil Engineering Sharif University of Technology

Different values have been assigned to the ratio of the defl ection amplifi cation factor(Cd) to the response modifi cation factor(R) for a specifi ed force-resisting system in the seismic design provisions while the same application is defi ned for it. An analytical study of the seismic responses of several reinforced concrete frames subjected to a suite of earthquake records performed in this research indicate that the stories’ overstrength and stiffness distribution along the structural height can affect local defl ections more than global ones. Therefore, the Cd/R ratio is calculated based on the ratio of both maximum inelastic to maximum elastic displacements and interstory drifts. Due to damage concentration in some specifi c stories, the defl ection amplifi cation factor calculated based on inelastic interstory drifts was larger than that of the inelastic displacements. Consequently, a minimum value of 1.0 is recommended for the Cd/R ratio in order to estimate maximum inelastic drifts. The ratio of inelastic to elastic displacement was generally found to increase slightly along the structural height for the studied RC models. In addition, it was detected that the story damage indices of the studied RC frames decrease when the inverted value of inelastic interstory drift ratios are increased through a(negative) power form.

关键词： deflection amplification factor nonlinear dynamic

Evaluation of Changes and Stability on the Surroundings Adjacent to Exhaust-Gas Emitting Port

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沈阳建筑大学学报(自然科学版) 2011年第3期27卷 541-546页

作者： AO Yong′an1,Marc A.Rosen2,WANG Yueren1(1.School of Municipal and Environmental Engineering,Shenyang Jianzhu University,Shenyang,China,110168 2.Faculty of Engineering and Applied Science,University of Ontario Institute of Technology,2000Simcoe Street North,Oshawa,Ontario,Canada,L1H7K4) School of Municipal and Environmental Engineering Shenyang Jianzhu University Shenyang 110168 China Faculty of Engineering and Applied Science University of Ontario Institute of Technology 2000 Simcoe Street North Oshawa Ontario L1H 7K4 Canada

The exergy and entropy changes of the surroundings adjacent to exhaust-gas emitting ports,and the probable effects on the atmosphere,are investigated and the current stable state changing point of atmosphere is determined and compared in the paper.The potential of doing work is described and the effects of the amount of exhaust gas on the atmosphere are studied through exergy and entropy change functions.The exergy change function accounts for the flow direction of the exhaust gas without local wind.It appears that exergy can be used as a state function to describe the change,the stability and the order of a system.

关键词： exergy entropy exhaust gas nonlinear dynamic atmosphere change

Investigation on a mitigation scheme to resist the progressive collapse of reinforced concrete buildings

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Frontiers of Structural and Civil Engineering 2012年第4期6卷 421-430页

作者： Iman TABAEYE IZADI Abdolrasoul RANJBARAN Department of Civil Engineering Faculty of EngineeringUniversity of ShirazShirazIran

This study presents the investigation of the approach which was presented by Thaer M.Saeed Alrudaini to provide the alternate load path to redistribute residual loads and preventing from the potential progressive collapse of RC buildings.It was proposed to transfer the residual loads upwards above the failed column of RC buildings by vertical cables hanged at the top to a hat steel braced frame seated on top of the building which in turn redistributes the residual loads to the adjacent columns.In this study a ten-storey regular structural building has been considered to investigate progressive collapse potential.Structural design is based on ACI 318-08 concrete building code for special RC frames and the nonlinear dynamic analysis is carried out using SAP2000 software,following UFC4-023-03 document.Nine independent failure scenarios are adopted in the investigation,including six external removal cases in different floors and three removal cases in the first floor.A new detail is proposed by using barrel and wedge to improve residual forces transfer to the cables after removal of the columns.Simulation results show that progressive collapse of building that resulted from potential failure of columns located in floors can be efficiently resisted by using this method.

关键词： prevent progressive collapse alternate load path reinforced concrete buildings nonlinear dynamic retrofitting cable steel hat braced frame barrel and wedge

Sensitivity to external optical feedback of circular-side hexagonal resonator microcavity laser

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Chinese Physics B 2021年第12期30卷 74-80页

作者：赵彤申志儒谢文丽郭龑强王安帮王云才 Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi ProvinceTaiyuan University of TechnologyTaiyuan 030024China College of Physics and Optoelectronics Taiyuan University of TechnologyTaiyuan 030024China Guangdong Provincial Key Laboratory of Photonics Information Technology Guangzhou 510006China School of Information Engineering Guangdong University of TechnologyGuangzhou 510006China

The sensitivity to fault reflection is very important for larger dynamic range in fiber fault detection technique.Using time delay signature(TDS)of chaotic laser formed by optical feedback can solve the sensitivity limitation of photodetector in fiber fault detection.The TDS corresponds to the feedback position and the fault reflection can be detected by the laser diode.The sensitivity to feedback level of circular-side hexagonal resonator(CSHR)microcavity laser is numerically simulated and the feedback level boundaries of each output dynamic state are demonstrated.The peak level of TDS is utilized to analyze the sensitivity.The demonstration is presented in two aspects:the minimum feedback level when the TDS emerges and the variation degree of TDS level on feedback level changing.The results show that the CSHR microcavity laser can respond to the feedback level of 0.07%,corresponding to-63-dB feedback strength.Compared to conventional distributed feedback laser,the sensitivity improves almost 20 dB due to the shorter internal cavity length of CSHR microcavity laser.Moreover,1%feedback level changing will induce 1.001 variation on TDS level,and this variation degree can be influenced by other critical internal parameters(active region side length,damping rate,and linewidth enhancement factor).

关键词： sensitivity optical feedback microcavity laser nonlinear dynamic