Fractional-Order Sliding Mode with Active Disturbance Rejection Control for UAVs by Zhikun Zhang, Hui Zhang

“…Firstly, the dynamic model of the UAV is established, and its nonlinear dynamic characteristics are analyzed in detail. …”
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PRIMARY RESONANCE ANALYSIS OF ARM SYSTEM UNDER BOUNDED NARROW⁃BAND EXCITATION by YANG ZhiAn, MAN ZhiJun, LIU WenYang

“…By using multi⁃scales method,the first primary resonance of the human arm and vibration mechanical coupling system under random narrow⁃band excitation was analyzed,and the two⁃degree⁃of⁃freedom nonlinear dynamic equation of the arm system was established.The first primary resonance amplitude frequency response equation and Ito stochastic differential equation of the system were solved in turn.In order to study the distribution law of variables under random vibration,the approximate expressions of the expectation and mean square value of the first primary resonance random mean square response were calculated using the moment estimation method.The influence of the parameters of the human arm system on the primary resonance was obtained through numerical analysis.The results show that the mean square response curves of the first primary resonance have the same topological structure as their amplitude⁃frequency response curves,and the mean square value of the primary resonance amplitudes and the resonance region increase with the increase of the amplitude of the external excitation,while the increase of the system damping will reduce the mean square value and the resonance region.The change of nonlinear stiffness coefficient has little effect on the system.…”
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Complexities in Assessing Structural Health of Civil Infrastructures by Abdullah Al-Hussein, Achintya Haldar

“…An unscented Kalman filter (UKF) concept is developed for highly nonlinear dynamic systems. It is denoted as 3D UKF-UI-WGI. …”
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RESEARCH ON DYNAMIC RESPONSE WITH CRASHWORTHY DEVICES OF OFFSHORE WIND TURBINE FUNDATION TO SHIP IMPACT by HAN ZhiWei, LI Chun, ZHOU HongJie, DING QinWei, YU Wan

“…The probability of collisions between offshore wind turbines and ships increases with the development of offshore wind farm. Based on nonlinear dynamic analysis method,through LS-DYNA to simulate the 5000 t ship impact a 4 MW offshore wind turbine tripod at different speed,study rubber-foam aluminum-steel crashworthy devices influence on structure dynamic response characteristics of tower in the process of collision. …”
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The Supply Chain Triangle: How Synchronisation, Stability, and Productivity of Material Flows Interact by Florian Klug

“…These models allow us to take into account the nonlinear, dynamical interactions of different supply chain echelons and to test synchronised and stable flow with respect to its potential impacts. …”
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Study on dynamics characteristic on combination misalignment and rubbing of the dual-rotor system by YAO Xia, NAN Guofang, LI Yao, QIU Xuewen

“…The misalignment of the dual-rotor system for the aero-engine will lead to abnormal increase of the vibration which results in the rotor-stator rubbing and affects the safty and stability of the rotor operation.The dual-rotor system was taken as the research object.Considering the combination misalignment-rubbing fault, the dynamic model of the rotor system is established based on the lumped mass method.The differential equation of the system motion was established according to the Lagrange equation, and the Range-Kutta method was used to solve it.The influence mechanism of the key parameters such as the speed, the misalignment angle and the coupling misalignment on the nonlinear dynamic characteristics of the system was studied.The results show that the system presents complex dynamic characteristics such as periodic, multi-periodic, quasi-periodic and chaotic motion with the increase of the rotor’s speed.When the speed is in the range of 1 500-2 200 rad/s, the system switches between periodic 2 motion and chaotic state through multiple paroxysmal bifurcations and paroxysmal inverted bifurcations.There are nonlinear phenomena such as jump in the bifurcation diagram of the vibration response with the change of the parallel misalignment of the coupling.As the misalignment angle of the bearing increases, the chaotic interval of the high speed decreases, and the stable periodic motion interval increases.…”
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Modeling, Testing, and Characteristic Analysis of a Planetary Flywheel Inerter by Zheng Ge, Weirui Wang

“…According to the structure of the planetary flywheel inerter, nonlinear factors of the inerter are analyzed, and a nonlinear dynamical model of the inerter is established. …”
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A NEW PREDICTION METHOD FOR RUL PREDICTION OF CRUSHER ROLL IN NON STATIONARY PARTIALLY OBSERVED STATE by WU JianJun, LIU HaiPing, YE Xiang

“…Then, the relationship between the residual life and the characteristic value is established, and the nonlinear dynamic change of the roll sleeve is described. …”
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Impact-Rubbing Dynamics of Rotor with Hollow Shaft and Offset Discs Based on MDOF Timoshenko Beam Theory by Guofang Nan, Xia Yao, Jingya Yao, Chao Wang

“…The research results indicate that the power turbine rotor with the hollow shaft on operation shows the various nonlinear dynamic behaviors including the multiperiod, quasi-period, jumping phenomenon, and chaotic motions; there exists an optimal gap between the rotor and the stator from the perspective of the efficiency and the dynamics; the optimal gap should make system avoid the resulting chaos or the quasi-period motion for the stability and safety of the machinery.…”
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Power Forecasting of Combined Heating and Cooling Systems Based on Chaotic Time Series by Liu Hai, Song Yong, Du Qingfu

“…Chaos is an inherent property of nonlinear dynamic system. A predicator of the output power of the distributed generation system is to establish a nonlinear model of the dynamic system based on real time series in the reconstructed phase space. …”
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Chaos Prediction in Fractional Delayed Energy-Based Models of Capital Accumulation by Mohamed El-Borhamy, Tamer Medhat, Manal E. Ali

“…This paper presents the nonlinear dynamic analysis of energy-based models arisen from the applied systems characterized by the energy transport in the presence of fractional order derivative and time delay. …”
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Analytical Redundancy of Variable Cycle Engine Based on Proper Net considering Multiple Input Variables and the Whole Engine’s Degradation by Zihao Zhang, Xianghua Huang, Tianhong Zhang

“…In another word, Proper net is proposed to solve a multivariable, strongly nonlinear, dynamic, and time-varying problem. In order to make the topological structure of Proper net physically explainable, Proper net’s topological structure is designed according to physical relationship between variables, by which means analytical redundancy based on Proper net achieves higher accuracy with less calculation time. …”
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Research on Aircraft Attitude Control Method Based on Linear Active Disturbance Rejection by Zhiguo Song, Changjian Zhao, Huiqiang Zhang, Tian Dong, Aojia Ma, Dawei Yan

“…Firstly, based on the nonlinear dynamic model of aircraft, the control system model with inner loop as angular velocity and outer loop as attitude angle is established. …”
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Modeling and Application of Process Damping in Milling of Thin-Walled Workpiece Made of Titanium Alloy by Xin Li, Wei Zhao, Liang Li, Ning He, ShengWei Chi

“…The paper presents one nonlinear dynamic model considering process damping for milling of thin-walled workpiece made of titanium alloy and designs antivibration clearance angle to suppress chatter based on the model. …”
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The inhibitory effect of intraspinal microstimulation of the sacral spinal cord on nonlinear bladder reflex dynamics in cats by Amirhossein Qasemi, Alireza Aminian, Abbas Erfanian

“…Bladder pressure was recorded under isovolumetric conditions, and the stimulation parameters were adjusted to inhibit spontaneous bladder contractions. Nonlinear dynamic methods, including chaos theory, were employed to analyze the complexity of bladder reflexes.ResultsResults demonstrated that ISMS targeting the dorsal horn of the S2 spinal segment effectively suppressed high-amplitude spontaneous contractions. …”
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Diagenetic Self-Organization and Stochastic Resonance in a Model of Limestone-Marl Sequences by Ivan L’Heureux

“…The model exhibits interesting features typical of nonlinear dynamical systems: (i) the existence of self-organized oscillating patterns between a calcite-rich mode (“limestone”) and a calcite-poor one (“marl”) for fixed environmental conditions and (ii) bistability between these two modes. …”
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STRIP ROLLING MILL’S RIGID-FLEXIBLE COUPLING VIBRATION MODELING by ZHANG Yang, PENG Yan, SUN JianLiang, ZANG Yong

“…Tandem strip mill is a complex system composed of a plurality of working frames and auxiliary equipments,each frame is a multi-variable,nonlinear dynamic system,and interacts with the adjacent one by the moving steel strip. …”
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Nonlinear Normal Modes in a Two-Stage Isolator Using a Modified Finite-Element Galerkin Method by Cheng Li, Hongguang Li

“…Besides the displacement of payload and the force transmissibility of this typical nonlinear dynamic system, the nonlinear normal modes defined as invariant manifolds can provide more information about the nonlinear coupling between the system components when periodic motions corresponding to the normal modes of the system occur. …”
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Progressive Collapse Analysis of Latticed Telecommunication Towers under Wind Loads by Shan Gao, Sheliang Wang

“…The present study conducts a nonlinear dynamic analysis on 50 m high typical standard latticed telecommunication tripole tower and angle tower by alternative load path method. …”
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Analysis of Gear Dynamic Characteristic of Oil Churning Resistance under Stochastic Disturbance by Wenyu Liu, Yongguo Sun, Guangbin Yu, Valerii Tupolev, Wei Liu

“…Thus，considering the backlash，time-varying mesh stiffness，transmission error，stochastic disturbances，oil churning resistance and other nonlinear factors， compares and analyzes the influence of oil churning resistance upon dynamic characteristics of the gear system under stochastic disturbance by establishing a nonlinear dynamic model of straight gears with 6 degrees of freedom and using by Lagrange method using the bifurcation diagram，phase diagram，Poincarè diagram，time-history graph and dynamic load factors （DLF） obtained by the R-K method. …”
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