采用模糊脉冲控制实现离散混沌系统的同步

利用模糊脉冲技术研究一类离散混沌系统的同步控制问题,建立离散混沌系统的离散T-S模糊动态模型,结合脉冲微分方程稳定理论,提出了一种新的离散混沌系统同步的模糊脉冲控制方法,把该方法应用到Henon映射系统中,仿真结果表明了该方法的有效性.     

马斯洛需要层次理论与党在不同时期思想政治教育内容同步性解读

马斯洛需要层次理论把需求分成生存需求、安全需求、感情需求、尊重需求和自我实现需求五类,依次由较低层次到较高层次[1]P67-69。经过仔细研读中国共产党各个时期思想政治教育方针,发现马斯洛需要层次理论与党在不同时期思想政治教育内容存在同步和一致性,通过对两者进行阐述和分析,最后得出同步性的确定结论,以期望对国家、集体制定相应的思想政治教育内容起到一定的借鉴作用。     

在足球理论课中实施异步教学法的实验研究

就异步教学法在体育专业足球理论课教学中的运用进行了探讨．研究结论表明,在足球理论课教学中运用异步教学法有利于提高学生学习兴趣、发展学生智力、培养学生的思维能力、提高学生自学能力和分析问题及解决问题的能力．     

Chaos in the fractional order unified system and its synchronization

The chaotic behaviors in the fractional order unified system are numerically investigated. By utilizing the fractional calculus techniques, we found that chaos exists in the fractional order unified system with order less than 3. The lowest order we found to have chaos in this system is 2.76. Chaos synchronization of the fractional order unified system is theoretically and numerically studied using the one-way coupling method. The suitable conditions for achieving synchronization of the fractional order differential system are derived by using the Laplace transform theory. It is noticed that the time required for achieving synchronization of the drive system and the response system and the synchronization effect sensitively depend on the coupling strength. Numerical simulations are performed to verify the theoretical analysis.     

一个新混沌系统的混沌特性分析及其同步

设计了一个新混沌系统实现同步的非线性控制器。根据李雅普诺夫稳定性定理,证明了同步误差系统是全局渐近稳定的。Matlab数值仿真结果表明。所设计的非线性控制器能有效地实现混沌同步。     

计算机操作系统课程中同步问题教学探讨

本文针对计算机科学技术专业的操作系统课程的进程同步教学问题进行了讨论,提出教学过程中应该增加可编程操作代码,让学生把抽象的知识变为具体可理解知识,本文还设计了“生产者与消费者关系”的同步教学代码。     

Synchronization within synchronization: transients and intermittency in ecological networks

Transients are fundamental to ecological systems with significant implications to management, conservation and biological control. We uncover a type of transient synchronization behavior in spatial ecological networks whose local dynamics are of the chaotic, predator–prey type. In the parameter regime where there is phase synchronization among all the patches, complete synchronization (i.e. synchronization in both phase and amplitude) can arise in certain pairs of patches as determined by the network symmetry—henceforth the phenomenon of  ‘synchronization within synchronization.’ Distinct patterns of complete synchronization coexist but, due to intrinsic instability or noise, each pattern is a transient and there is random, intermittent switching among the patterns in the course of time evolution. The probability distribution of the transient time is found to follow an algebraic scaling law with a divergent average transient lifetime. Based on symmetry considerations, we develop a stability analysis to understand these phenomena. The general principle of symmetry can also be exploited to explain previously discovered, counterintuitive synchronization behaviors in ecological networks.     

Digitalizing interorganizational relationships: Sequential and intertwined decisions for data synchronization

Digitalizing interorganizational relationships (IORs) concerns B2B partners adopting and using Interorganizational Information Systems (IOSs). The decision to digitalize IORs involves choices about (1) whether or not to digitalize information flows, and (2) which technology to use. We explore whether these two choices are made sequentially or if they are intertwined. Using sequential adoption theory and institutional theory, we investigate the decisions related to digitalizing IORs through data synchronization. In the context of product information in the French consumer goods and retail industries, analysis of 18 case studies (large firms and SMEs) provides empirical evidence on the distinction between the two related decisions and the factors influencing each one. Our propositions integrate institutional pressures, observational learning, organizational capabilities and technological characteristics.     

一种混沌同步系统及其在保密通信中的应用

混沌信号的非周期性连续宽带频谱,类似噪声的特性,使它具有天然的隐蔽性,因此近年来混沌同步及在保密通信中的应用受到了广泛的关注。混沌在保密通信中的应用具有强大的生命力,其关键技术是实现混沌的同步。本文论述了基于无刷式直流电机的混沌模型,同时利用状态观测器实现了发送端与接收端的同步;最后提出了基于无刷式直流电机的混沌同步保密通信系统模型,并通过仿真证明了该模型的有效性。     

使用试错法加快扩频通信伪随机码捕获

An optimun search algorithm for the coherent acquisition in direct-sequence spread-spectrum （DSSS） receivers is proposed and analyzed in this paper. The system consists of two major parts： a phase region estimator and a phase alignment detector. We use an auxiliary sequence to correlate the incoming signal in the phase region estimator. Since the cross-correlation value between the auxiliary sequence and the incoming PN signal has linear magnitude, and can provide the direction for the phase updating, an optimum search algorithm, try and error method, can be adopted to obtain the phase region information of the incoming signal. The mean acquisition time is derived through the signal flow graph theory. The time is compared with that of the conventional serial search scheme, and the results show that the proposed scheme can achieve coarse acquisition significantly faster than the conventional scheme.