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71.
本文研究了一类自治泛函微分方程的普遍方面和泛函方面对解的性质的影响,在较为广泛的前提下证明了这类方程解的存在性唯一性、有界性及渐近性. 相似文献
72.
In this paper, we consider the integration of the special second‐order initial value problem. Hybrid Numerov methods are used, which are constructed in the sense of Runge‐Kutta ones. Thus, the Taylor expansions at the internal points are matched properly in the final expression. A new family of such methods attaining eighth algebraic order is given at a cost of only 7 function evaluations per step. The new family provides us with an extra parameter, which is used to increase phase‐lag order to 18. We proceed with numerical tests over a standard set of problems for these cases. Appendices implementing the symbolic construction of the methods and derivation of their coefficients are also given. 相似文献
73.
Modified function projective lag synchronization of chaotic systems with disturbance estimations 总被引:1,自引:0,他引:1
This paper addresses the modified function projective lag synchronization (MFPLS) for a class of chaotic systems with unknown external disturbances. The disturbances are supposed to be generated by the exogenous systems. By using the disturbance-observer-based control and the linear matrix inequality approach, the disturbance observers are developed to ensure the boundedness of the disturbance error dynamics. Then by employing the sliding mode control (SMC) technique, an active SMC law is established to guarantee the disturbance rejection and realize MFPLS between the master and slave systems. And the corresponding numerical simulation is provided to illustrate the effectiveness of the proposed method. 相似文献
74.
Xiangjun Wu Hongtao Lu 《Communications in Nonlinear Science & Numerical Simulation》2012,17(7):3005-3021
Generalized function projective (lag, anticipated and complete) synchronization between two different complex networks with nonidentical nodes is investigated in this paper. Based on Barbalat’s lemma, some sufficient synchronization criteria are derived by applying the nonlinear feedback control. Although previous work studied function projective synchronization on complex dynamical networks, the dynamics of the nodes are coupled partially linear chaotic systems. In our work, the dynamics of the nodes of the complex networks are any chaotic systems without the limitation of the partial linearity. In addition, each network can be undirected or directed, connected or disconnected, and nodes in either network may have identical or different dynamics. The proposed strategy is applicable to almost all kinds of complex networks. Numerical simulations further verify the effectiveness and feasibility of the proposed synchronization method. Numeric evidence shows that the synchronization rate is sensitively influenced by the feedback strength, the time delay, the network size and the network topological structure. 相似文献
75.
We discuss Bayesian modelling of the delay between dates of diagnosis and settlement of claims in Critical Illness Insurance using a Burr distribution. The data are supplied by the UK Continuous Mortality Investigation and relate to claims settled in the years 1999-2005. There are non-recorded dates of diagnosis and settlement and these are included in the analysis as missing values using their posterior predictive distribution and MCMC methodology. The possible factors affecting the delay (age, sex, smoker status, policy type, benefit amount, etc.) are investigated under a Bayesian approach. A 3-parameter Burr generalised-linear-type model is fitted, where the covariates are linked to the mean of the distribution. Variable selection using Bayesian methodology to obtain the best model with different prior distribution setups for the parameters is also applied. In particular, Gibbs variable selection methods are considered, and results are confirmed using exact marginal likelihood findings and related Laplace approximations. For comparison purposes, a lognormal model is also considered. 相似文献
76.
ZHANG Qun-Jiao LU Jun-An JIA Zhen 《理论物理通讯》2009,51(4):679-683
This paper investigates the projective synchronization and lag synchronization of a new hyperchaotic system [Physica A 364 (2006) 103]. On the basis of Lyapunov stability theory, two novel nonlinear controllers are respectively designed to guarantee the global exponential projective synchronization (including complete synchronization and antisynchronization) and lag synchronization. Finally, numerical simulations are given to show the effectiveness of the main results. 相似文献
77.
78.
针对已有文献研究城镇化时忽视的服务业的空间集聚效应以及经济增长对人口城镇化的非线性关系的问题,文章根据第六次全国人口普查数据,利用半参数空间滞后模型实证研究了我国人口城镇化的影响因素。结果表明:(1)服务业的发展大力推动了我国区域人口城镇化发展,且它的影响强度明显高于工业化发展所带来的影响。服务业集聚效应对该省的人口城镇化具有促进作用,第二产业集聚对该省的人口城镇化的作用不显著。(2)经济欠发达地区(云贵川等)的经济增长对人口城镇化的促进作用较小。而多数位于中部和沿海经济较发达地区(福建、广州等)的经济增长显著促进了人口城镇化的发展。然而,在经济发达地区(如上海、北京、浙江)的经济增长对人口城镇化的促进效果明显开始减弱,甚至是负向的关系。(3)半参数空间滞后模型比普通参数模型具有更高的拟合优度和更丰富的结论,它能够有效刻画城镇化过程中空间相关性与非线性特征。 相似文献
79.
Curved beam structures have been used in many civil, mechanical, aircraft, and aerospace constructions. The analysis is mainly based on solid and plate models due to the fact that traditional curved beam elements do not include nonuniform warping effects, especially in the dynamic analysis. In this article, independent warping parameters have been taken into account and the initial curvature effect is considered. Curved beam’s behavior becomes more complex, even for dead loading, due to the coupling between axial force, bending moments, and torque that curvature produces. In addition to these, the Isogeometric tools (b-splines or NURBS), either integrated in the Finite Element Method or in a Boundary Element–based Method called Analog Equation Method, have been employed in this contribution for the dynamic analysis of horizontally curved beams of open or closed (box-shaped) cross sections. Free vibration characteristics and responses of the stress resultants and displacements to moving loading have been studied. 相似文献
80.
钱塘江二桥变截面连续箱形梁剪滞效应的分析 总被引:1,自引:0,他引:1
本文结合钱塘江二桥应用变分法推导了变截面箱形梁剪滞效应的微分方程并利用有限差分法求得解答。所得结果与大桥工程局桥梁科学研究所模型试验数据比较吻合。最后通过有限元法,验证了理论分析并对钱塘江二桥的剪滞效应进行分析。 相似文献