分数阶复杂网络的同步分析

本文主要研究了节点动力学为Caputo型的分数阶微分方程的复杂网络的同步,建立了判定分数阶网络的同步定理.数值例子验证了理论结果的有效性.     

一类节点数不同的不确定时空网络的指数外同步

研究了节点数不同的不确定时空网络的指数外同步问题.首先,基于Lyapunov稳定性定理,通过设计合理的控制器,实现了两个节点数不同的不确定时空网络的指数外同步.进一步确定了表示网络拓扑结构的耦合矩阵元和反馈强度的自适应律.最后,以一维Burgers系统和Logistic系统构成的时空网络为例进行了仿真模拟.结果表明,整个网络存在稳定的指数外同步现象.并且同步的速率依赖于可调参数,而网络节点数不影响整个网络同步的稳定性,说明该同步方案具有一定的普适性.     

节点状态不同的两个耦合网络的同步

本文研究了节点动力学不同的两个耦合网络的同步,我们发现两个耦合网络之间不能达到同步,但是他们可以达到各自的同步态．利用线性化方法,我们给出了相应的定理,并用数值例子验证了理论结果．     

广义稠密随机交集图的度分布(英文)

广义随机交集图是一类重要的随机图模型,它是E-R随机图的变种,被广泛用于复杂社会网络的研究中.本文研究了在顶点度的期望趋于无穷的情况下,广义随机交集图的度分布.我们对二项模型给出了中心极限定理,并且对一致模型给出了极限定理.     

异维混沌动力系统的有限时间广义同步

本文研究了异维混沌动力系统的有限时间广义同步的问题.利用有限时间Lyapunov稳定性定理、Jensen不等式等理论方法,通过设置不同的控制器,从理论上提出了一般的异维驱动系统和响应系统的有限时间广义同步的两种方案,并且对方案二中的影响同步时间因素做了理论分析和证明.最后,数值模拟验证了提出理论的正确性和可行性.     

具有时延和无时延加权多智能体系统一致性

针对存在全局可达节点有向加权图的静态网络,研究了在控制算法中引入不同权重的当前状态和时延状态时多智能体系统一致性问题.通过采用频域控制理论中广义Nyquist准则和Gerschgorin圆盘定理,证明了系统渐近稳定收敛到一致性的充分条件,提出一种改进系统实现一致性的最大时延上界方法;最后通过数值仿真验证了结论的正确性.     

多层二分耦合网络的同步性研究

多层复杂网络的同步能力分析是目前网络科学研究的热点.首先根据主稳定方程(MSF)给出多层二分耦合网络的超拉普拉斯矩阵,并得到反映其同步能力的重要指标.其次分析了二分耦合网络在同步域有界和无界的两种情况下层数、二分耦合网络节点数、层间耦合强度和层内耦合强度对同步能力的影响.最后通过数值模拟和理论实践提出控制层数、二分耦合网络节点数、层间耦合强度和层内耦合强度等参数的策略,来实现优化多层二分耦合网络的同步能力,为工程技术人员在实际应用中优化其同步能力提供有效的方案.     

广义伪分形网络上随机游走的平均首达时间的精确幂律

研究具有一个吸收点的广义伪分形网络上随机游走的平均首达时间.广义伪分形网络的显著特点是在每一次迭代中,每条现有的边会产生有限个节点.根据网络的演化算法,得到了平均首达时间的精确表达式.当网络的阶数足够大时,平均首达时间是按照网络节点数的幂律在增长.此外,可以通过改变网络参数来改善此类网络的随机游走的效率.这些研究结果是对伪分形网络相应结果的推广,将为深入研究各类分形网络的随机游走提供帮助.     

随机连接广义合作网络模型

本文提出了一个项目参与者数T是随机变量的广义合作网络模型,新节点与随机选择的节点合作,通过节点度演化所满足的马尔可夫性,利用马．尔可夫链的方法和技巧得到了度分布的精确解析表达式．并说,明了此广义合作网络不是无标度网络．     

复杂动态网络的有限时间同步

复杂网络无处不在,同步是自然界中广泛存在的一类非常重要的非线性现象.过去10年,人们对复杂网络的同步开展了系统而深入的研究,包括恒等同步、广义同步、簇同步以及部分同步等.上述大部分结果中对同步速度的刻画往往是渐进的,只有当时间趋于无穷的时候,网络才能实现同步,而对于网络能够在多长时间内可以实现同步却知之甚少.作者以几类典型的非线性耦合的复杂动态网络为例,深入探讨了复杂动态网络的有限时间同步的规律.具体而言,基于上述几类典型的复杂动态网络,证明了在某些合适的条件下,网络能够在有限时间内实现精确同步.此外,用一个典型的数值仿真实例验证了上述有限时间同步的准则.有限时间同步有效地避免了网络只有在无穷时刻才能实现同步的问题,对网络同步的实际工程应用具有基本的现实意义.     

Generalized synchronization between two different complex networks

In this paper, generalized synchronization (GS) between two coupled complex networks is theoretically and numerically studied, where the node vectors in different networks are not the same, and the numbers of nodes of both networks are not necessarily equal. First, a sufficient criterion for GS, one kind of outer synchronizations, of two coupled networks is established based on the auxiliary system method and the Lyapunov stability theory. Numerical examples are also included which coincide with the theoretical analysis.     

Generalized synchronization of strictly different systems: Partial-state synchrony

Generalized synchronization (GS) occurs when the states of one system, through a functional mapping are equal to states of another. Since for many physical systems only some state variables are observable, it seems convenient to extend the theoretical framework of synchronization to consider such situations. In this contribution, we investigate two variants of GS which appear between strictly different chaotic systems. We consider that for both the drive and response systems only one observable is available. For the case when both systems can be taken to a complete triangular form, a GS can be achieved where the functional mapping between drive and response is found directly from their Lie-algebra based transformations. Then, for systems that have dynamics associated to uncontrolled and unobservable states, called internal dynamics, where only a partial triangular form is possible via coordinate transformations, for this situation, a GS is achieved for which the coordinate transformations describe the functional mapping of only a few state variables. As such, we propose definitions for complete and partial-state GS. These particular forms of GS are illustrated with numerical simulations of well-known chaotic benchmark systems.     

Emergence of a common generalized synchronization manifold in network motifs of structurally different time-delay systems

We point out the existence of a transition from partial to global generalized synchronization (GS) in symmetrically coupled structurally different time-delay systems of different orders using the auxiliary system approach and the mutual false nearest neighbor method. The present authors have recently reported that there exists a common GS manifold even in an ensemble of structurally nonidentical scalar time-delay systems with different fractal dimensions and shown that GS occurs simultaneously with phase synchronization (PS). In this paper we confirm that the above result is not confined just to scalar one-dimensional time-delay systems alone but there exists a similar type of transition even in the case of time-delay systems with different orders. We calculate the maximal transverse Lyapunov exponent to evaluate the asymptotic stability of the complete synchronization manifold of each of the main and the corresponding auxiliary systems, which in turn ensures the stability of the GS manifold between the main systems. Further we estimate the correlation coefficient and the correlation of probability of recurrence to establish the relation between GS and PS. We also calculate the mutual false nearest neighbor parameter which doubly confirms the occurrence of the global GS manifold.     

Hölder continuity of three types of generalized synchronization manifolds of non-autonomous systems

This paper studies the existence of Hölder continuity of the generalized synchronization (GS) manifold. When the modified response system has an asymptotically stable equilibrium, periodic or quasi-periodic orbit, and chaotic attractor, GS is classified into four types accordingly. The first three types of GS are considered, and based on the Schauder fixed point theorem, sufficient conditions for Hölder continuous GS in the coupled non-autonomous systems are derived and theoretically proved.     

Hölder continuity of three types of generalized synchronization manifolds of non-autonomous systems

This paper studies the existence of Hölder continuity of the generalized synchronization (GS) manifold. When the modified response system has an asymptotically stable equilibrium, periodic or quasi-periodic orbit, and chaotic attractor, GS is classified into four types accordingly. The first three types of GS are considered, and based on the Schauder fixed point theorem, sufficient conditions for Hölder continuous GS in the coupled non-autonomous systems are derived and theoretically proved.     

权有附加约束的条件下的DEA有效性(C2R或C2GS2)

有关判别决策单元在权有附加约束的条件下是否DEA有效（C^2或C^2GS^2)，本文给出了一种基于权有附加约束条件下的加性模型的不同于文献[1]与[2]的约束与差别法。     

A time-domain decomposition iterative method for the solution of distributed linear quadratic optimal control problems

We study a class of time-domain decomposition-based methods for the numerical solution of large-scale linear quadratic optimal control problems. Our methods are based on a multiple shooting reformulation of the linear quadratic optimal control problem as a discrete-time optimal control (DTOC) problem. The optimality conditions for this DTOC problem lead to a linear block tridiagonal system. The diagonal blocks are invertible and are related to the original linear quadratic optimal control problem restricted to smaller time-subintervals. This motivates the application of block Gauss–Seidel (GS)-type methods for the solution of the block tridiagonal systems. Numerical experiments show that the spectral radii of the block GS iteration matrices are larger than one for typical applications, but that the eigenvalues of the iteration matrices decay to zero fast. Hence, while the GS method is not expected to convergence for typical applications, it can be effective as a preconditioner for Krylov-subspace methods. This is confirmed by our numerical tests.A byproduct of this research is the insight that certain instantaneous control techniques can be viewed as the application of one step of the forward block GS method applied to the DTOC optimality system.     

Generalized synchronization of two bidirectionally coupled discrete dynamical systems

Based on the modified system approach the generalized synchronization (GS) in two bidirectionally coupled discrete dynamical systems is classified into several types, and under some conditions, the existence, Lipschitz smoothness and Hölder continuity of two kinds of GS therein are derived and theoretically proved. In addition, numerical simulations validate the present theory.     

加性DEA模型与规模收益

[1]给出了用C^2R模型或C^2GS^2模型来判断决策单元的规模收益情况的定理,指出它有时失效。对DEA有效（C^2GS^2）的决策单元,本用加性DEA模型来有效地判断其规模收益情况。     

组大小为10的广义Steiner三元系

广义Steiner三元系GS(2,3,n,g)等价于g+1元最优常重量码(n,3,3)。本文证明了GS(2,3,n,10)存在的必要条件n≡0,1(mod3),n≥12也是充分的。