基于以太网的Modbus/TCP协议的实时性研究

以Modbus和TCP传输协议为研究对象，对其协议性机理进行了的研究。在此基础上，在Quantum系列PLC的以太网通信模块与上位监控站之间，做了基于Modbus／TCP传输协议的实时性测试。其测试的结果是Modbus／TCP传输协议用于工业控制中是可行的。     

基于Modbus协议的三菱PLC与E700变频器通信实例

介绍了三菱FX3U系列PLC和三菱E700变频器通信的硬件连接、参数设置及程序编写，实现了对E700变频器的控制和实时数据采集。Modbus协议是一种工业控制的现场总线协议，介绍了PLC的Modbus通信协议的设置和变频器数据的Modbus地址的查询，具有一定的实用性。     

基于Modbus TCP/IP协议的Premium PLC网络

介绍了Modbus TCP/IP协议结构和基于Modbus TCP/IP协议的Premium PLC网络的组建方法.     

基于PM-160网关的S7-300系列PLC与智能流量计之间的数据通信

本文以西门子S7-300系列PLC与智能流量计之间的数据通信为例,介绍如何实现Modbus和PROFIBUS—DP协议设备的相互通信,重点描述了上海泗博自动化的Modbus转PROFIBUS-DP网关PM-160在其中的应用,以及这两种不同通信协议的通信方式。     

Modbus TCP通信协议在PLC课程中的应用

传统PLC课程采用的通信协议主要是西门子S7协议、三菱CC-LINK协议,只能用于同种PLC之间的通信。而Modbus TCP通信协议可匹配多种不同类型的工业控制设备,能够极其方便地在不同类型设备间建立可靠稳定快速的通信。因此,本文介绍了Modbus TCP通信协议在PLC课程中的应用。     

基于嵌入式ARM的Modbus/TCP协议的研究与实现

Modbus/TCP工业以太网是运行在TCP/IP协议栈上的Modbus报文传输协议.分析了Modbus/TCP的协议构成及其体系结构,在嵌入式ARM7和嵌入式实时操作系统μC/OS-II平台上实现了Modbus/TCP协议的客户端和服务器端应用程序,并进行了相关测试.方案能有效实现工业现场的数据采集、处理和Modbus/TCP通信功能.     

Modbus TCP/IP协议的客户端与服务器实现

针对工业以太网通信在自动化控制系统中应用,介绍了Modbus TCP/IP传输协议,提出了如何在自动化仪表中利用套接字实现Modbus TCP/IP协议,给出了在ARM9实验板上实现Modbus TCP/IP服务器和电脑上实现客户端的方法和实例,并详细介绍了程序的软件流程图。调试结果表明,该服务器/客户端可以有效地进行数据传输,为研发人员对仪表实现Modbus TCP/IP协议提供了方法,并有效促进了Modbus TCP/IP在自动化仪表中的应用。     

基于Modbus/TCP协议的工业控制通信

在介绍Modbus/TCP协议模式及结构的基础上,分析系统的通信机制,详细叙述工业控制系统中基于Modbus/TCP协议的工控机与PLC的通信实现过程,给出采用VC6.0编制的客户端主要源程序代码,以及服务器端的硬件环境和软件设置.经实验,证明Modbus/TCP是工业自动化领域较好的以太网解决方案.     

面向OPC监控平台的Modbus/TCP协议网关研究

工业以太网两设备之间通信的协议主要是Modbus/TCP协议。对传统Modbus协议和Modbus/TCP协议数据帧的格式进行分析,特别为了保证工业以太网OPC监控系统数据的安全性和可靠性,提出网络接口冗余切换算法和网络接口MAC地址绑定,能保证OPC监控系统的实时安全性。在Modbus/TCP协议的工业以太网上实现水泥OPC监控系统,以OPCServer系统和OPCClient系统,两个子系统实现工业机器的参数和数据的控制,并在互连网上进行动态显示。根据动态的数据和参数,对机器进行有效的控制和操作,也可以进行远距离的查询数据,确保整个系统和机器的安全。     

Modbus通信协议PLC主站软件设计

文中首先介绍了Modbus通信协议,然后针对控制系统中需要以PLC为Modbus通信主站的情况,以西门子S7—200PLC对台达变频器进行远程控制为例,阐述了在以Modbus通信的方式对设备进行远程控制时PLC主站的软件设计方法。     

Assessing Ideational and Evaluative Skills and Creative Styles and Attitudes

This article describes the rationale for the multiphase creative problem solving process, and reports the findings from an empirical investigation conducted to facilitate the problem solving of managers. The ideational skills of the managers were assessed before and after training in a complete process of creative problem solving, along with their ideational attitudes, creative problem solving style (i.e., generator, conceptualizer, optimizer, or implementor), and evaluative skill (i.e., ability to recognize original ideas). The most important findings indicated that the training had a significant impact on the evaluative accuracy of the managers. They were significantly more accurate in their judgments about original ideas after training, both in their identification of original ideas and their recognition of unoriginal ideas. After training, the managers also gave more solutions and more original solutions to problems. Finally, several variables (e.g., the “preference for active divergence” attitude, and the conceptualizer process style) seemed to moderate the impact of training. Training was therefore effective, with specific effects that can be predicted from pre-training individual differences in attitudes and process style.     

Rank and select revisited and extended

The deep connection between the Burrows–Wheeler transform (BWT) and the so-called rank and select data structures for symbol sequences is the basis of most successful approaches to compressed text indexing. Rank of a symbol at a given position equals the number of times the symbol appears in the corresponding prefix of the sequence. Select is the inverse, retrieving the positions of the symbol occurrences. It has been shown that improvements to rank/select algorithms, in combination with the BWT, turn into improved compressed text indexes.     

高等院校行政分析与决策系统的设计与实现

为提高高等院校的管理水平和决策水平,充分利用校园网资 源,开发了高等院校行政财政分析与决策系统。解决了诸如数据的动态查询、自动生成报表 、网络环境下数据共享等技术问题,具有网上数据共享、图形界面友好和安全的保密措施等 特点。     

Stochastic balancing and approximation-stability and minimality

A new method of stochastic model reduction has recently been introduced by Desai et al. [1], [2]. The stability of the reduced order model has not previously, been considered. In this paper, we show that the stability of the reduced order model follows directly from the results of Pernebo and Silverman [3]. It is also shown that the reduced order model is minimal, in the controllability/observability sense. The relevance of this notion of minimality to stochastic minimality is made clear.