Sinking型和Sourcing型数字信号I/O接口应用

当为控制系统选择数字信号输入/输出模块的接口类型时,正确理解Sinking Current(灌电流)和Sourcing Current(拉电流)的概念是非常重要的。讨论数字信号输入/输出接口/连接电路时会经常使用这些术语,在设计与负载连接的电路时,除了考虑电压、电流、功率等匹配外,更要注意灌电流型和拉电流型DI/O的区别,以使得连接电路更合理、可靠,逻辑表达更清楚和正确。     

如何提高糠醛的产量

通过控制加酸的量及改造锅炉来提高糠醛的产量。     

A novel approach to output feedback control of fuzzy stochastic systems

This paper investigates the problem of Hankel-norm output feedback controller design for a class of T–S fuzzy stochastic systems. The full-order output feedback controller design technique with the Hankel-norm performance is proposed by the fuzzy-basis-dependent Lyapunov function approach and the conversion on the Hankel-norm controller parameters. Sufficient conditions are established to design the controllers such that the resulting closed-loop system is stochastically stable and satisfies a prescribed performance. The desired output feedback controller can be obtained by solving a convex optimization problem, which can be efficiently solved by standard numerical algorithms. Finally, a Henon map system is used to illustrate the effectiveness of the proposed techniques.     

一种面向测试的载波频偏盲同步算法及仿真

在无线通信中,由于信号在传输过程中不可避免地受到各种干扰,接收信号一般与发送信号存在一个较大的频率偏差,传统的解决方法是利用快速傅里叶变换得到接收信号中的频率幅度信息,从而对频率偏差进行补偿校正,但是由于通信速率的不断提高,频谱闪变现象加剧,传统的方法已经不能满足要求。提出一种改进的算法,对快速傅里叶过程中的时域数据进行重叠处理,并在输出端进行平滑处理,有效地减小频率偏差估计中的误差,并通过MatLab仿真与现有算法的仿真结果进行分析比较,证明该算法的可行性和有效性。     

基于PROFIBUS-DP的智能远程IO通信设备的设计和实现

基于PROFIBUS-DP的智能远程IO通信设备是符合PROFIBUS-DP协议的从站设备,是模块化分布式的I/O系统,具有卡件扫描功能,能够实现过程输入和输出数据从现场到控制室的远距离、全数字、双向传输,能够弥补常规分散控制系统(DCS)将过程的输入、输出集中集成在自动化系统中的不足,是DCS系统实现分布式自动化应用的理想解决方案。详细介绍了基于ProfiBus-DP的智能远程IO通信设备的设计和实现方法。     

Global Robust Output Regulation for a Class of Switched Nonlinear Systems with Nonlinear Exosystems

The problem of global robust output regulation for a class of switched nonlinear systems with nonlinear exosystems is investigated in this paper where not all subsystems are stabilizable. First, as an extension of the concept of non‐switched internal model, this paper defines a switched internal model, which together with the plant is called the switched augmented system. Also, we show that the problem of output regulation for the switched nonlinear system can be converted into a global robust regulation problem of the switched augmented system. Second, based on the average dwell time method, the global robust regulation problem under a class of switching signals with average dwell time is solved, which leads to the solution of the problem of global robust output regulation. Finally, an example is provided to demonstrate the effectiveness of the proposed design approach.     

Global sampled-data output feedback control for a class of feedforward nonlinear systems

This paper investigates the problem of global output feedback stabilization for a class of feedforward nonlinear systems via linear sampled-data control. To solve the problem, we first construct a linear sampled-data observer and controller. Then, a scaling gain is introduced into the proposed observer and controller. Finally, we use the sampled-data output feedback domination approach to find the explicit formula for choosing the scaling gain and the sampling period which renders the closed-loop system globally asymptotically stable. A simulation example is given to demonstrate the effectiveness of the proposed design procedure.     

常压法三聚氰胺生产工艺

介绍了常压法生产三聚氰胺的工艺技术,并提出了一些此方法中提高三胺收率的方法.     

一种自毁执行装置的设计

为满足武器系统的安全性、可靠性要求,设计了一种自毁执行装置,详细阐述了自毁执行装置中传爆部件及爆炸器的设计,并对自毁执行装置的传爆、输出威力等进行验证试验。结果表明,自毁执行装置结构设计合理,安全性好、可靠性高,可以满足武器系统需要。     

国内外锌市场状况和分析

简述了国内外锌市场和世界锌资源状况,介绍了锌精矿供应、精锌生产、消费及价格等方面的情况,并对锌市场进行了分析和预测。