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大学生英语学习动机变化机制研究--动态系统理论视角下的个案分析 被引量:22
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作者 常海潮 《外语电化教学》 CSSCI 北大核心 2018年第5期35-41,75,共8页
本研究采用轨迹等效建模法,从动态系统理论视角考察4名大学生英语学习动机的变化机制及其影响因素。结果发现:(1)各类考试是动机系统吸引子状态的主要成因,动机轨迹围绕各类考试呈历时波动趋势;(2)动机系统起始状态不同,且与动机强度之... 本研究采用轨迹等效建模法,从动态系统理论视角考察4名大学生英语学习动机的变化机制及其影响因素。结果发现:(1)各类考试是动机系统吸引子状态的主要成因,动机轨迹围绕各类考试呈历时波动趋势;(2)动机系统起始状态不同,且与动机强度之间呈非线性关系;(3)动机变化机制既涉及社会、学校、课堂等外在环境因素,也涉及兴趣、焦虑等学习者内在因素。教师须重视学习者个体差异,最大限度调动学生学习动机。二语习得研究者应转变研究范式,从动态角度对个体差异进行历时考察。 展开更多
关键词 二语动机自我系统 动态系统理论 起始状态 吸引子
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大学生英语学习动机中的吸引子状态研究——基于二语动机自我系统的个案分析 被引量:17
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作者 常海潮 《中国外语》 CSSCI 北大核心 2019年第2期55-63,共9页
本研究采用轨迹等效建模法,从动态系统理论的吸引子视角考察4名大学生英语学习动机的变化机制及其影响因素。结果发现:(1)动机轨迹呈现高阶和普通两层面吸引子,前者由"积极英语自我"构成,后者由"愉快的英语学习经历"... 本研究采用轨迹等效建模法,从动态系统理论的吸引子视角考察4名大学生英语学习动机的变化机制及其影响因素。结果发现:(1)动机轨迹呈现高阶和普通两层面吸引子,前者由"积极英语自我"构成,后者由"愉快的英语学习经历"构成;(2)各类英语考试是动机轨迹中吸引子盆的主要成因;(3)"积极英语自我"和"愉快学习经历"是激发学习动机的主要因素,动机强度围绕英语考试起伏波动。英语教师宜及时引导学生树立定向目标,并合理规划考试和优化课堂教学,最大程度激发学生学习动机。 展开更多
关键词 二语动机 动态系统理论 吸引子 英语教学
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GLOBAL ATTRACTOR OF NONLINEAR STRAIN WAVES IN ELASTIC WAVEGUIDES 被引量:14
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作者 戴正德 郭柏灵 《Acta Mathematica Scientia》 SCIE CSCD 2000年第3期322-334,共13页
The initial-boundary value problem of the propagation of nonlinear longitudinal elastic waves in an initially strained rod is considered. The rod is assumed to interact with the surrouding elastic and viscous external... The initial-boundary value problem of the propagation of nonlinear longitudinal elastic waves in an initially strained rod is considered. The rod is assumed to interact with the surrouding elastic and viscous external medium. The long time behavior of solutions are derived and global attractors in E-1 space is obtained. 展开更多
关键词 nonlinear strain waves attractors
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Design and implementation of a novel multi-scroll chaotic system 被引量:13
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作者 张朝霞 禹思敏 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第1期119-129,共11页
This paper proposes a novel approach for generating a multi-scroll chaotic system. Together with the theoretical design and numerical simulations, three different types of attractor are available, governed by construc... This paper proposes a novel approach for generating a multi-scroll chaotic system. Together with the theoretical design and numerical simulations, three different types of attractor are available, governed by constructing triangular wave, sawtooth wave and hysteresis sequence. The presented new multi-scroll chaotic system is different from the classical multi-scroll chaotic Chua system in dimensionless state equations, nonlinear functions and maximum Lyapunov exponents. In addition, the basic dynamical behaviours, including equilibrium points, eigenvalues, eigenvectors, eigenplanes, bifurcation diagrams and Lyapunov exponents, are further investigated. The success of the design is illustrated by both numerical simulations and circuit experiments. 展开更多
关键词 multi-scroll chaotic attractors triangular and sawtooth waves hysteresis sequence circuit implementation
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The Global Attractors and Their Hausdorff and Fractal Dimensions Estimation for the Higher-Order Nonlinear Kirchhoff-Type Equation with Strong Linear Damping 被引量:11
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作者 Yunlong Gao Yuting Sun Guoguang Lin 《International Journal of Modern Nonlinear Theory and Application》 2016年第4期185-202,共18页
In this paper, we study the longtime behavior of solution to the initial boundary value problem for a class of strongly damped Higher-order Kirchhoff type equations: . At first, we prove the existence and uniqueness o... In this paper, we study the longtime behavior of solution to the initial boundary value problem for a class of strongly damped Higher-order Kirchhoff type equations: . At first, we prove the existence and uniqueness of the solution by priori estimation and the Galerkin method. Then, we obtain to the existence of the global attractor. At last, we consider that the estimation of the upper bounds of Hausdorff and fractal dimensions for the global attractors are obtained. 展开更多
关键词 Nonlinear Higher-Order Kirchhoff Type Equation The Existence and Uniqueness The Global attractors Hausdorff Dimensions Fractal Dimensions
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Lorenz系统的动力学特性及对称特性 被引量:4
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作者 刘孝贤 刘晨 《山东工业大学学报》 1998年第6期501-508,共8页
对 Lorenz系统的不动点进行了深入研究 ,对 Lorenz吸引子的对称性和周期性作了分析讨论 .针对 Lorenz系统微分方程特点 ,研究采用了迭代图形方法和数学分析方法 .结果表明 ,Lorenz系统不仅具有动力学特性 (混沌特性和奇异吸引子特性 ) ... 对 Lorenz系统的不动点进行了深入研究 ,对 Lorenz吸引子的对称性和周期性作了分析讨论 .针对 Lorenz系统微分方程特点 ,研究采用了迭代图形方法和数学分析方法 .结果表明 ,Lorenz系统不仅具有动力学特性 (混沌特性和奇异吸引子特性 ) ,还具有对称性和周期性 .特别 ,文章首次给出一组新的有关 展开更多
关键词 动力系统 吸引子 LORENZ系统 非线性 微分方程组
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基于混沌理论的检测技术进展 被引量:7
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作者 张健 王竹萍 +2 位作者 吕宁 于晓洋 陈德运 《电子器件》 EI CAS 2005年第2期307-311,共5页
混沌理论作为一门新学科已经引起了世界各国科学界的重视,是近年来非线性科学领域的热门学科。混沌系统的初值敏感性和长期不可预测等一系列特点使得混沌理论可以应用于包括检测在内的很多领域。介绍基于混沌理论检测技术的国内外研究现... 混沌理论作为一门新学科已经引起了世界各国科学界的重视,是近年来非线性科学领域的热门学科。混沌系统的初值敏感性和长期不可预测等一系列特点使得混沌理论可以应用于包括检测在内的很多领域。介绍基于混沌理论检测技术的国内外研究现状,主要包括基于Duffing振子的频率测量;基于初值敏感性的电压、电阻、电容、电感的测量;基于猎取法的临界值检测;基于MWM算法的信号分离技术;基于Feigenbaum映射的灵敏度测试等。对各种测量原理进行了评述,对研究现状进行了评价,并提出了进一步研究的重点。 展开更多
关键词 混沌 DUFFING振子 吸引子 检测技术
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The Global Attractors for the Higher-Order Kirchhoff-Type Equation with Nonlinear Strongly Damped Term 被引量:7
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作者 Yuting Sun Yunlong Gao Guoguang Lin 《International Journal of Modern Nonlinear Theory and Application》 2016年第4期203-217,共16页
We investigate the global well-posedness and the global attractors of the solutions for the Higher-order Kirchhoff-type wave equation with nonlinear strongly damping: . For strong nonlinear damping σ and ?, we make a... We investigate the global well-posedness and the global attractors of the solutions for the Higher-order Kirchhoff-type wave equation with nonlinear strongly damping: . For strong nonlinear damping σ and ?, we make assumptions (H<sub>1</sub>) - (H<sub>4</sub>). Under of the proper assume, the main results are existence and uniqueness of the solution in proved by Galerkin method, and deal with the global attractors. 展开更多
关键词 Strongly Nonlinear Damped Higher-Order Kirchhoff Equation The Existence and Uniqueness The Global attractors
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An Examination of the Function of Male Flowers in an Andromonoecious Shrub Capparis spinosa 被引量:7
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作者 Tao Zhang Dun-Yan Tan 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2009年第3期316-324,共9页
The pollen donor and pollinator attractor hypotheses are explanations for the functions of the male flowers of andromonoecious plants. We tested these two hypotheses in the andromonoecious shrub Capparis spinosa L. (... The pollen donor and pollinator attractor hypotheses are explanations for the functions of the male flowers of andromonoecious plants. We tested these two hypotheses in the andromonoecious shrub Capparis spinosa L. (Capparaceae) and confirmed that pollen production and cumulative volume and sugar concentration of nectar do not differ between male and perfect flowers. However, male flowers produced larger anthers, larger pollen grains and smaller ovaries than perfect flowers. Observations on pollinators indicated that two major pollinators (Xylocopa valga Gerst and Proxylocopa sinensis Wu) did not discriminate between flower morphs and that they transferred pollen grains a similar distance. However, there were more seeds per fruit following hand pollination with pollen from male flowers than from perfect flowers. Individuals of C. spinosa with a larger floral display (i.e. bearing more flowers) received more pollen grains on the stigma of perfect flowers. Female reproductive success probably is not limited by pollen. These results indicate that male flowers of C. spinosa save resources for female function and that they primarily serve to attract pollinators as pollen donors. 展开更多
关键词 ANDROMONOECY Capparis spinosa pollen donor pollinator attractors reproductive success.
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磨合过程摩擦振动混沌吸引子演变规律 被引量:8
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作者 孙迪 李国宾 +2 位作者 魏海军 崔洋 廖海峰 《振动与冲击》 EI CSCD 北大核心 2015年第6期116-121,共6页
在CFT-I型试验机上进行摩擦副磨合试验,应用混沌理论研究摩擦振动吸引子,探讨磨合过程中摩擦振动混沌吸引子的演变规律。结果表明,摩擦振动吸引子在相空间一定区域内具有特定层次结构且永不封闭轨迹。摩擦振动具有混沌行为的基本特征;... 在CFT-I型试验机上进行摩擦副磨合试验,应用混沌理论研究摩擦振动吸引子,探讨磨合过程中摩擦振动混沌吸引子的演变规律。结果表明,摩擦振动吸引子在相空间一定区域内具有特定层次结构且永不封闭轨迹。摩擦振动具有混沌行为的基本特征;随磨损过程的进行,摩擦振动混沌吸引子逐渐收缩并趋于稳定,混沌吸引子变化能反映摩擦副从磨合磨损到稳定磨损状态变化;摩擦振动混沌吸引子体积变化可用于摩擦副的磨合磨损状态预测与识别。 展开更多
关键词 磨合 摩擦振动 混沌 吸引子 演变规律
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Discontinuous bifurcation and coexistence of attractors in a piecewise linear map with a gap 被引量:5
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作者 屈世显 卢永智 +1 位作者 张林 何大韧 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第12期4418-4423,共6页
Coexistence of attractors with striking characteristics is observed in this work, where a stable period-5 attractor coexists successively with chaotic band-ll, period-6, chaotic band-12 and band-6 attractors. They are... Coexistence of attractors with striking characteristics is observed in this work, where a stable period-5 attractor coexists successively with chaotic band-ll, period-6, chaotic band-12 and band-6 attractors. They are induced by dif- ferent mechanisms due to the interaction between the discontinuity and the non-invertibility. A characteristic boundary collision bifurcation, is observed. The critical conditions are obtained both analytically and numerically. 展开更多
关键词 coexistence of attractors piecewise linear map mapping hole discontinuous bifurcation
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正反馈系统理论 被引量:6
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作者 郑维敏 《系统工程理论与实践》 EI CSCD 北大核心 1997年第3期28-34,共7页
负反馈是控制系统中基本而又重要的一环。负反馈可以使控制系统的过程按一定的轨迹运动,有着广泛的应用。至于正反馈,人们常常联系到不稳定。其实正反馈系统有着非常丰富的内容和应用范围。本文将通过一些例子。
关键词 系统理论 迭代系统 正反馈系统 反馈系统
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混沌吸引子的重构 被引量:4
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作者 林梓 李魁俊 +1 位作者 王丽 张晓婷 《长春邮电学院学报》 1999年第3期7-12,共6页
研究了一种通过实验数据来确定混沌吸引子结构的新方法——相空间重构法, 即根据混沌系统中某一状态量的一维时间序列, 用时延技术进行吸引子重构。通过在一个三阶自治混沌电路中用该方法的分析, 验证了相空间重构法的可行性及正确性。
关键词 混沌 相空间 重构 自相关 吸引子
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Multi-scroll hidden attractors and multi-wing hidden attractors in a 5-dimensional memristive system 被引量:3
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作者 胡晓宇 刘崇新 +2 位作者 刘凌 姚亚鹏 郑广超 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第11期120-126,共7页
A novel 5-dimensional(5D) memristive chaotic system is proposed, in which multi-scroll hidden attractors and multiwing hidden attractors can be observed on different phase planes. The dynamical system has multiple l... A novel 5-dimensional(5D) memristive chaotic system is proposed, in which multi-scroll hidden attractors and multiwing hidden attractors can be observed on different phase planes. The dynamical system has multiple lines of equilibria or no equilibrium when the system parameters are appropriately selected, and the multi-scroll hidden attractors and multi-wing hidden attractors have nothing to do with the system equilibria. Particularly, the numbers of multi-scroll hidden attractors and multi-wing hidden attractors are sensitive to the transient simulation time and the initial values. Dynamical properties of the system, such as phase plane, time series, frequency spectra, Lyapunov exponent, and Poincar′e map, are studied in detail. In addition, a state feedback controller is designed to select multiple hidden attractors within a long enough simulation time. Finally, an electronic circuit is realized in Pspice, and the experimental results are in agreement with the numerical ones. 展开更多
关键词 multi-scroll hidden attractors multi-wing hidden attractors multiple lines equilibria no equilibrium
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A Family of the Exponential Attractors and the Inertial Manifolds for a Class of Generalized Kirchhoff Equations 被引量:4
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作者 Guoguang Lin Lujiao Yang 《Journal of Applied Mathematics and Physics》 2021年第10期2399-2413,共15页
In this paper, we studied a family of the exponential attractors and the inertial manifolds for a class of generalized Kirchhoff-type equations with strong dissipation term. After making appropriate assumptions for Ki... In this paper, we studied a family of the exponential attractors and the inertial manifolds for a class of generalized Kirchhoff-type equations with strong dissipation term. After making appropriate assumptions for Kirchhoff stress term and nonlinear term, the existence of exponential attractor is obtained by proving the discrete squeezing property of the equation, then according to Hadamard’s graph transformation method, the spectral interval condition is proved to be true, therefore, the existence of a family of the inertial manifolds for the equation is obtained. 展开更多
关键词 Kirchhoff-Type Equation Spectral Interval Condition A Family of the Exponential attractors A Family of the Inertial Manifolds
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Dynamics of Plate Equations with Memory Driven by Multiplicative Noise on Bounded Domains
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作者 Mohamed Y. A. Bakhet Abdelmajid Ali Dafallah +5 位作者 Jing Wang Qiaozhen Ma Fadlallah Mustafa Mosa Ahmed Eshag Mohamed Paride O. Lolika Makur Mukuac Chinor 《Journal of Applied Mathematics and Physics》 2024年第4期1492-1521,共30页
This article examines the dynamics for stochastic plate equations with linear memory in the case of bounded domain. We investigate the existence of solutions and bounded absorbing set by using the uniform pullback att... This article examines the dynamics for stochastic plate equations with linear memory in the case of bounded domain. We investigate the existence of solutions and bounded absorbing set by using the uniform pullback attractors on the tails estimates, and the asymptotic compactness of the random dynamical system is proved by decomposition method, and then we obtain the existence of a random attractor. 展开更多
关键词 Plate Equations Random attractors Memory Term Dynamical Systems
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Pullback Attractors for a Damped Semilinear Wave Equation with Delays 被引量:4
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作者 Kai Xuan ZHU Yong Qin XIE Feng ZHOU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2018年第7期1131-1150,共20页
In this paper, we consider the weakly damped wave equations with hereditary effects, and the nonlinearity f satisfies critical growth. The delay term g(t, ut) may be driven by a function with very weak assumptions, ... In this paper, we consider the weakly damped wave equations with hereditary effects, and the nonlinearity f satisfies critical growth. The delay term g(t, ut) may be driven by a function with very weak assumptions, namely, just measurability. We analyze the well-posedness of solutions and verify the existence of the pullback :D-attractor in CH01(Ω) × CL2 (Ω) by constructing the energy functional and combining with the idea of the contractive function. 展开更多
关键词 Wave equations critical nonlinearity DELAYS pullback attractors
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Random Attractors for the Kirchhoff-Type Suspension Bridge Equations with Strong Damping and White Noises 被引量:4
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作者 Chuangliang Qin Jinji Du Guoguang Lin 《International Journal of Modern Nonlinear Theory and Application》 2017年第4期134-147,共14页
In this paper, we investigate the existence of random attractor for the random dynamical system generated by the Kirchhoff-type suspension bridge equations with strong damping and white noises. We first prove the exis... In this paper, we investigate the existence of random attractor for the random dynamical system generated by the Kirchhoff-type suspension bridge equations with strong damping and white noises. We first prove the existence and uniqueness of solutions to the initial boundary value conditions, and then we study the existence of the global attractors of the equation. 展开更多
关键词 Kirchhoff-Type SUSPENSION Bridge Equations RANDOM attractors RANDOM DYNAMICAL System
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单摆混沌现象的研究 被引量:6
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作者 李纪强 周斌 丁益民 《湖北大学学报(自然科学版)》 CAS 2013年第4期513-517,共5页
利用MATLAB软件强大的数值计算功能,使用龙格库塔法严格求解无阻尼单摆和有阻尼单摆的运动方程,研究单摆摆长、阻尼系数和初始摆角对单摆运动的影响.研究结果表明:单摆的周期与初始摆角有关,单摆周期随初始摆角的增大而增大;当两种单摆... 利用MATLAB软件强大的数值计算功能,使用龙格库塔法严格求解无阻尼单摆和有阻尼单摆的运动方程,研究单摆摆长、阻尼系数和初始摆角对单摆运动的影响.研究结果表明:单摆的周期与初始摆角有关,单摆周期随初始摆角的增大而增大;当两种单摆的参数取值处于某些范围时,均能出现混沌现象;阻尼单摆在正阻尼条件下演化出随机吸引子,在负阻尼条件下演化出随机排斥子.通过计算不同参数值的单摆方程,发现单摆的运动对初始摆角、阻尼系数有很强的依赖性.最后提出了一种衡量混沌系统敏感性的量化指标——敏感系数,计算结果表明,初始摆角、单摆摆长、阻尼系数均能影响单摆的敏感系数. 展开更多
关键词 MATLAB 单摆 龙格库塔法 混沌 吸引子 敏感性
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Random Attractors for Stochastic Reaction-Diffusion Equations with Distribution Derivatives on Unbounded Domains 被引量:3
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作者 Eshag Mohamed Ahmed Ali Dafallah Abdelmajid +1 位作者 Ling Xu Qiaozhen Ma 《Applied Mathematics》 2015年第10期1790-1807,共18页
In this paper, we prove the existence of random attractors for a stochastic reaction-diffusion equation with distribution derivatives on unbounded domains. The nonlinearity is dissipative for large values of the state... In this paper, we prove the existence of random attractors for a stochastic reaction-diffusion equation with distribution derivatives on unbounded domains. The nonlinearity is dissipative for large values of the state and the stochastic nature of the equation appears spatially distributed temporal white noise. The stochastic reaction-diffusion equation is recast as a continuous random dynamical system and asymptotic compactness for this demonstrated by using uniform estimates far-field values of solutions. The results are new and appear to be optimal. 展开更多
关键词 STOCHASTIC REACTION-DIFFUSION Equation Random attractors DISTRIBUTION DERIVATIVES Asymptotic Compactness Unbounded Domain
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