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IEEE International conference on Fuzzy Systems (FUZZ-IEEE)

作者： Pham, Tuan D. Oyama-Higa, Mayumi Linkoping Univ Dept Biomed Engn S-58183 Linkoping Sweden Chaos Technol Res Lab Otsu Shiga 5202134 Japan

ISBN: (纸本)9781509060207

Photoplethysmogram (PPG) signals obtained from wearable sensors have been utilized for monitoring health conditions in both clinical and non-clinical environments, mostly concerning with heart-rate events. This paper shows the potential use of short-time PPG signals for differentiating patients with Parkinson's disease (PD) from healthy control (HC) subjects with nonlinear dynamics analysis. Multiscale entropy, time-shift multiscale entropy, and fuzzy recurrence plots were applied for extracting features from PPG signals of PD patients and HC subjects. Least-square support vector machine based cross-validations of the features extracted from the three nonlinear dynamics analysis methods achieve high classification rates, where those obtained from fuzzy recurrence plots are the highest.

关键词： Photoplethysmography wearable sensors nonlinear dynamics fuzzy logic Parkinson's disease

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The edge of chaos in kinematics and dynamics of mechanism 4th

The edge of chaos in kinematics and dynamics of mechanism

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4th conference on Mechanisms, Transmissions and Applications, MeTrApp 2017

作者： Liu, Zhaohui Xie, Jin Chen, Yong Southwest Jiaotong University Chengdu China

ISBN: (纸本)9783319607016

Edge of chaos is a new concept deriving from complexity. Its significance for mechanism science is described in this paper. It is demonstrated that one can obtain all solutions of nonlinear equations by Newton’s method utilizing the edge of chaos. And in dynamic analysis and controlling of mechanism, where the models usually are nonlinear dynamic system, one is able to understand something about the arising of chaos, and find efficient measures to control and anti-control chaos through studying of edge of chaos. Following these, some methods to detect the edge of chaos are introduced briefly. © Springer International Publishing AG 2018.

关键词： Kinematics

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CMMSE2017: On two classes of fourth- and seventh-order vectorial methods with stable behavior

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JOURNAL OF MATHEMATICAL CHEMISTRY 2018年第7期56卷 1902-1923页

作者： Cordero, Alicia Guasp, Lucia Torregrosa, Juan R. Univ Politecn Valencia Inst Matemat Multidisciplinar Camino Vera S-N E-46022 Valencia Spain

A family of fourth-order iterative methods without memory, for solving nonlinear systems, and its seventh-order extension, are analyzed. By using complex dynamics tools, their stability and reliability are studied by means of the properties of the rational function obtained when they are applied on quadratic polynomials. The stability of their fixed points, in terms of the value of the parameter, its critical points and their associated parameter planes, etc. give us important information about which members of the family have good properties of stability and whether in any of them appear chaos in the iterative process. The conclusions obtained in this dynamical analysis are used in the numerical section, where an academical problem and also the chemical problem of predicting the diffusion and reaction in a porous catalyst pellet are solved.

关键词： nonlinear system of equations Iterative method Dynamical and Parameter planes Stability

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Contact interaction of flexible Timoshenko beams with small deflections 11

Contact interaction of flexible Timoshenko beams with small ...

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11th International Scientific and Technical conference on Applied Mechanics and dynamics Systems

作者： Papkova, I. V. Krysko, A. V. Saltykova, O. A. Zakharova, A. A. Krysko, V. A. Saratov State Tech Univ Dept Math & Modelling Politehn Skaya Str 77 Saratov Russia Tomsk Polytech Univ Dept Engn Graph & Ind Design Sovetskaya Str 84-3 Tomsk Russia

In this work chaotic dynamics contact interaction of two flexible Tymoshenko beams, under the action of a transversal alternating load is investigated. The contact interaction of the beams is taken into account by the Kantor model. The geometric nonlinearity is taken into account by the model of T. von Karman. The system of partial differential equations of the twelfth order reduces to the system of ordinary differential equations by the method of finite differences of the second order. The resulting system by methods of Runge-Kutta type of the second, fourth and eighth orders was solved. Our theoretical/numerical analysis is supported by methods of nonlinear dynamics and the qualitative theory of differential equations. Chaotic vibrations of two flexible beams of Timoshenko were investigated and the optimal step values over the spatial coordinate and the time steps for the numerical experiment were found. Convergence for all applicable numerical methods have been achieved and shown that chaotic signals are true.

关键词： Contact interaction Timoshenko's beam chaos finite difference method Runge-Kutta type methods geometric nonlinearity

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UNCERTAINTY PROPAGATION OF REENTRY TRAJECTORY UNDER PIECEWISE CONTINUOUS CONTROL 4th

UNCERTAINTY PROPAGATION OF REENTRY TRAJECTORY UNDER PIECEWIS...

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4th International-Academy-of-Astronautics conference on dynamics and Control of Space Systems (DyCoSS '2018)

作者： He, Xiangyue Li, Haiyang Huang, Yuechen Natl Univ Def Technol Coll Aerosp Sci & Engn Changsha 410073 Hunan Peoples R China

ISBN: (纸本)9780877036531

Reentry is an important phase for the vehicle returning to the Earth, and uncertainty propagation in reentry dynamics has become a hot topic in recent years. The main task of this paper is to investigate the statistic characteristic of the reentry trajectory with crossrange corridor under parameter uncertainties. Specifically, the non-smooth feature of the lateral control with crossrange corridor, which is shown as the reversal of the bank, is mainly considered. Hence the control law turns to be a typical piecewise continuous function, and the uncertainty propagation becomes nonlinear. The nonintrusive polynomial chaos expansion based method and the Monte Carlo simulation are introduced for the analysis. Results show that the distribution of the final crossrange would be obviously impacted by the crossrange corridor, which won't fit the same distribution of the initial parameter uncertainties. Our research can provide a theoretical basis for the analysis of the reentry trajectory uncertainty propagation.

关键词： Monte Carlo methods

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A HYBRID SYMBOLIC-NUMERIC COMPUTATIONAL METHOD FOR ANALYSIS OF BILINEAR SYSTEMS

A HYBRID SYMBOLIC-NUMERIC COMPUTATIONAL METHOD FOR ANALYSIS ...

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ASME International Design Engineering Technical conferences (IDETC) / Computers and Information in Engineering conference (CIE)

作者： Tien, Meng-Hsuan D'Souza, Kiran Ohio State Univ Dept Mech & Aerosp Engn Columbus OH 43210 USA

ISBN: (纸本)9780791851852

In this paper, an efficient and accurate computational method for determining responses of high-dimensional bilinear systems is developed. Predicting the dynamics of bilinear systems is computationally challenging since the piecewise-linear nonlinearity induced by contact eliminates the use of efficient linear analysis techniques. The new method, which is referred to as the hybrid symbolic-numeric computational (HSNC) method, is based on the idea that the entire nonlinear response of a bilinear system can be constructed by combining linear responses in each time interval where the system behaves linearly. The linear response in each time interval can be symbolically expressed in terms of the initial conditions. The transition time where the system switches from one linear state to the other and the displacement and velocity at the instant of transition are solved using a numerical scheme. The entire nonlinear response can then be obtained by joining each piece of the linear response together at the transition time points. The HSNC method is based on using linear features to obtain large computational savings. Both the transient and steady-state response of bilinear systems can be computed using the HSNC method. Thus, nonlinear characteristics, such as subharmonic motion, bifurcation, chaos, and multi stability, can be efficiently analyzed using the HSNC method. The HSNC method is demonstrated on a single degree of freedom system and a cracked cantilever beam model, and the nonlinear characteristics of these systems are examined.

关键词： Computational methods

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Efficient modelling of a nonlinear gust loads process for uncertainty quantification of highly flexible aircraft

Efficient modelling of a nonlinear gust loads process for un...

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AIAA/ASCE/AHS/ASC Structures, Structural dynamics, and Materials conference, 2018

作者： Cook, Robert G. Wales, Christopher J. A. Gaitonde, Ann L. Jones, Dorian P. Cooper, Jonathan E. University of Bristol University Walk Queen’s Building BristolBS8 1TR United Kingdom Department of Aerospace Engineering United Kingdom AFAIAA Department of Aerospace Engineering United Kingdom

ISBN: (数字)9781624105326

ISBN: (纸本)9781624105326

An efficient gust loads process is presented which can predict worst case loads on a highly flexible aircraft, for use in uncertainty quantification. This process generates a neural network surrogate model of an aeroelastic system using linearised system equations to rapidly determine worst gust cases, including the capability to model atypical gust excitations. The surrogate model is used to produce a reduced set of identified gust cases which cause the largest loads;these cases are then run in the nonlinear code. Uncertainty quantification of this gust process is carried out using polynomial chaos expansion (PCE) techniques, considering uncertain structural properties. Convergence studies of the gust loads using PCE indicate significantly fewer samples are required than would be for a Monte Carlo simulation. It is demonstrated how oblique gusts exceed the loads envelope from a traditional gust process, justifying the need to consider alternative gust excitations, but interestingly for the particular test case in this work, uncertain structural properties can be seen to have little effect on the uncertainty of the static 1g and gust loads. © 2018, (publisher Name). All Rights reserved.

关键词： Monte Carlo methods

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On finding battery age through ground truth based data driven approach

On finding battery age through ground truth based data drive...

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Asian Control conference

作者： Aamer Iqbal Bhatti Muhammad Farhan Usman Zafar Qadeer Ahmed Faculty of Electrical Engineering Capital University of Science and Technology Islamabad Pakistan Office of Research Innovation and Commercialization Capital University of Science and Technology Islamabad Pakistan MS student at Capital University of Science and Technology Islamabad Pakistan Center for Automotive Research The Ohio State University Columbus

ISBN: (纸本)9781728102634

Determining the age of a battery under use is a highly critical but unsolved problem. On one hand , knowing battery age improves the reliability of the system using the battery. On the other hand, safety critical systems have to use new batteries on the start of each run, resulting in huge battery costs. There are numerous attempts at finding the battery age but owing to the nonlinear nature of the chemical processes in a battery, its modeling is a challenging problem. Battery ageing problem has been traditionally treated in a model-based FDI framework. The FDI techniques mostly depend upon the precision of the battery model. Obtaining accurate battery models is still an unsolved problem. Recently, data driven methods are getting acceptable by the industry owing to the ready availability of data and the growing trend towards data analytics. However, these data driven methods are not able to benefit from the battery dynamics and ground truth, considering the battery as a black box. A hybrid but rigorous approach, based on structural analysis and clustering concepts, is proposed which takes the best of both worlds by devising data driven FDI methodology benefiting from the ground truth provided by the battery models based FDI. This approach puts rigour into the classical data driven approaches. It also earmarks the right battery variables to be used in the data analysis, thus considerably decreasing the data size involved. Also it annotates the results of unsupervised learning which are hard to understand. The proposed hybrid approach is applied on predicting the age of Lithium-Ion battery showing the efficacy of the approach while demonstrating the effective use of the battery data with an approximate model of the battery.

关键词： Lithium-ion batteries Mathematical model Estimation Resistance Aging Data models

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Galloping behavior analysis of transmission line with thin ice accretions 34

Galloping behavior analysis of transmission line with thin i...

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34th International conference on Vibroengineering 2018

作者： Cui, Fujiang Liu, Xijun Zhang, Suxia Huo, Bing Zhou, Anqi Shi, Ruizhi Department of Mechanics School of Mechanical Engineering Tianjin University Tianjin300354 China Tianjin Key Laboratory of Nonlinear Dynamics and Chaos Control Tianjin300354 China College of Mechanical Engineering Tianjin University of Science and Technology Tianjin300222 China

A dynamic model of a galloping transmission line able to describe for the coupling of its longitudinal, in-plane, out-of-plane and torsional vibrations is established. It also considers the effects of geometrical nonlinearity and aerodynamic nonlinearity. By the static configuration, the reduced model is obtained. Then, the equations of motion are obtained through the Galerkin method. It contains two in-plane, two out-of-plane and two torsional components. By numerical calculation, the maximum amplitudes at wind speeds are drawn and the galloping behavior of transmission line with thin ice accretions is analyzed. The obtained results show that the second galloping mode is more triggered. The double-mode galloping occurs in all motions, in which the maximum amplitude is bigger than in single-mode galloping. And the double-mode galloping presents the track of inclined ‘8’ in longitudinal direction. © 2018 Fujiang Cui, et al.

关键词： Galerkin methods

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A New 2D Hénon-Logistic Map for Producing Hyperchaotic Behavior

A New 2D Hénon-Logistic Map for Producing Hyperchaotic Beha...

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Scientific conference of Electrical Engineering (SCEE)

作者： Wafaa A. Hussein Nadia M. G. Al-Saidi Hayder Natiq Department of Applied Sciences University of Technology - Iraq Baghdad Iraq Universiti Putra Malaysia Serdang Selangor MY

ISBN: (纸本)9781728115887;9781728115870

Derived from the two-dimensional (2D) Hénon map and the one-dimensional (1D) Logistic map, this paper proposes a new 2D hyperchaotic map, called the 2D Hénon-Logistic map (2D-HLM). The dynamics of the 2D-HLM are investigated by means of equilibria, stability analysis, trajectory, Lyapunov exponent, and bifurcation diagram. Mathematical analysis reveals that the 2D-HLM has four unstable equilibria. Besides that, it has wide chaotic and hyperchaotic behaviors with very limited periodic windows. To evaluate the complexity performance of the 2D-HLM, Approximate entropy is used to analyze its time series. Consequently, the 2D-HLM exhibits extremely complex nonlinear behavior. With all of these attributes, the 2D-HLM would be very appropriate to produce a pseudo-random number generator that can be used in chaos-based cryptographic applications.

关键词： bifurcation chaos cryptography entropy Lyapunov methods nonlinear dynamical systems random number generation pseudorandom number generation Lyapunov methods nonlinear dynamical systems cryptography BIFURCATION entropy chaos Pseudorandom number generator MAPPING(MATHEMATICAL) maps bifurcation diagram

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