基于System Generator的内插位同步法

针对数字接收机中如何全数字地实现位同步,设计了一种内插位同步法。利用内插与Gardner算法相结合的原理设计位同步,通过System Generator进行建模仿真,并直接生成代码下载到FPGA实现位同步。利用QPSK信号进行仿真分析,FPGA硬件协同仿真进行验证。实验结果表明,内插位同步法具有很好的位同步效果。     

小波变换实现5涡卷超混沌吸引子的同步

为了节约通信信道资源,采用小波变换去掉反馈变量的细节信息从而压缩其频带的方法实现了两个5涡卷超混沌吸引子的同步。在发送端,将系统的z变量通过小波滤波器滤出高频成分,将低频成分重构后发送到接收端,接收端将该信号作为反馈信号,实现了收发系统的同步。应用本同步方法不仅可以节约信道资源,同时,由于发送的信号已不是完整的混沌信号,也提高了系统的保密性。     

基于Windows数控系统的多线程实现

本文介绍了基于Windows平台数控系统的多线程的实现方法，着重阐述了数控系统多线程实现的线程创建、优先级设定和线程同步问题。     

混凝土泵送系统集成控制方法研究

针对泵送技术中的油缸换向可靠性差、液压系统换向冲击大、泵送效率低等技术难点,以泵送单元的控制为研究对象,通过对相关传递函数模型、状态空间描述模型的深入分析,提出一种泵送系统集成冗余控制方法:采用独特的信号采集方式,通过控制器闭环实时调整泵送系统的串联油缸同步状态,一体化解决上述泵送系统控制的技术难点。还探讨了这种串联油缸实时同步控制的控制律及实用的中央控制器运算策略,建立了VR泵送单元三维动态可视化模型及Simulink泵送单元动态系统模型,而其中的串缸同步补泄油逻辑控制模型,还利用StateFlow状态流建模技术。基于统一的MATLAB软件平台,对该控制方法进行必要的仿真,以验证该方法的可行性,并在实际工况下验证了该控制方法的技术优势。     

Synchronization for linear singularly perturbed complex networks with coupling delays

This paper is concerned with the synchronization problem about linear singularly perturbed complex network system with coupling delay. The sufficient delay-dependent conditions for the synchronization of the network are established by introducing an equivalent network system with the Lyapunov stability theory. These conditions, which are formulated in terms of linear matrix inequalities, can be solved efficiently by the LMI toolbox of MATLAB. A simulation example is provided to show the validity of the proposed the synchronization conditions of the whole network.     

基于区域扩散机制的无线传感器网络时间同步算法

针对当前无线传感器网络时间同步算法无法满足物联网对于网络实时性的要求,提出了一种基于区域扩散的无线传感器网络时间同步算法。该算法分为两个阶段进行:第一阶段根据生物觅食理论(OFT),按照收益率最高的原理提出一种代言人信息选择算法(SIE)进行区域内时间同步;第二阶段根据时间偏移量最小节点选择区域代言人并在区域之间进行二次同步,同时将同步过程映射到马尔可夫链,提出基于马尔可夫链的代言人加速算法(MarSAA)。理论分析和实验证明,提出的算法具有较好的时间复杂性;并且两阶段算法可以并行进行,相对于传统算法在全网时间同步上具有非常好的性能。     

Performance control for interconnection of identical systems: Application to PLL network design

In this paper, the problem of the control law design for interconnected identical systems ensuring the global stability and the global performance properties is under consideration. Inspired by the decentralized control law design methodology using the dissipativity input–output approach, the problem is reduced to the problem of satisfying two conditions: (i) the condition on the interconnection and (ii) the condition on the local subsystem dynamics. Both problems are efficiently solved applying a (quasi‐) convex LMI optimization and standard H_∞ synthesis. The proposed design methodology is applied to the control law design of a synchronous PLL network. Copyright © 2014 John Wiley & Sons, Ltd.     

Synchronization of a class of nonlinear network flow systems

In this paper, we consider the synchronization of a class of nonlinear network flow systems. Motivated by air distribution problem in air conditioning and mechanical ventilation (ACMV) systems, we propose a class of coupled nonlinear multi‐agent systems that can model a wide class of network flow systems, including air flow in ACMV systems, water flow in irrigation systems, traffic flow in transportation systems, and so on. Then we consider the synchronization problem for the class of nonlinear multi‐agent systems and propose cooperative controllers for the system. Based on graph theory, we derive conditions on the initial values of the state and the control input such that synchronization can be achieved. An application to air ventilation is provided to demonstrate the effectiveness of the cooperative controllers. Copyright © 2015 John Wiley & Sons, Ltd.     

Control of Julia Sets in Generalized Alternated System

In this paper, we first introduce the generalized alternated system. The definition of the Julia set in the generalized alternated system is given, which is called a generalized alternated Julia set. Then, we achieve the control of generalized alternated Julia sets by applying the classic control methods, which are gradient control and optimal control. In addition, the synchronization between two different generalized alternated Julia sets is implemented using gradient control and optimal control. The simulations illustrate the effectiveness and correctness of these two control methods, and the results are displayed in 2D computer graphics.     

基于北斗的高速摄像机时间同步器设计

为了满足民用飞机在飞行试验中高速摄像机对时间同步的需求,基于国产北斗卫星导航系统设计了具有精确输出IRIG-B(AC)码的时间同步器,用于机载高速摄像机的精确时间同步。以FPGA为核心,使用直接数字频率合成技术实现了IRIG-B(AC)码的产生。实验结果表明,该同步器时间同步精度满足要求,可以实现对高速摄像机进行时间同步的功能。