用VB6.0实现西门子PLC与PC机的串行通讯

对西门子系列PLC的通讯协议进行了详细的介绍,并以VB6.0开发系统在WINDOWS环境下实现了PC机与西门子系列PLC之间的串行通讯.文章给出了PLC和VB6.0相关的主要程序,通过该通讯程序实现了PC机对西门子系列PLC的监控和控制.同时本程序对PC机与其他型号PLC之间的通讯也有一定的借鉴意义.     

基于S7-200 PLC的自由端口通信的研究和实现

研究自由端口通信在计算机与西门子S7-200PLC之间数据传输中的应用与实现.论述下位机PLC程序和上位PC机VB程序的设计思路以及具体实现,通过与西门子同类软件的性能比较,结果表明自由端口通信程序软件提高了计算机与PLC之间的数据传输效率,且运行稳定.     

Windows环境下PLC与上位机的串行通信

以日本 OMRON公司 C2 0 0 H系列可编程控制器为例 ,介绍了 Windows环境下利用 VB6.0实现 PC与 PLC串行通信的方法。重点讨论了 OMRON C2 0 0 HE系列 PLC的通信功能及 VB6.0平台上上位机串行通信程序的设计。所研究的方法和编制的程序已成功地应用于教改项目“测控专业综合实验平台”中。     

利用VB6.0实现PC机与PLC的串行通讯

介绍了上位计算机和PLC的通讯实现方法.通过设置西门子PLC为自由口通讯模式,在上位计算机中使用VB6.0进行编程,实现了上、下位机之间的串行通讯.结果表明,两者的通讯具有良好的可靠性.文中给出了部分程序清单.     

PLC恒压供水上位机控制系统的开发

本设计基于VB 6.0实现西门子S7-200系列PLC与上位机之间的串行通信,旨在提高PLC控制系统的实时监控性,完善实验台控制系统的控制功能。一方面,利用VB 6.0制作友善的人机监控界面,可以根据需要设置输入参数并实时显示实验输出结果;另一方面,通过VB 6.0提供的串行通信ActiveX控件MSComm,采用自由口通信协议实现PLC与上位机之间的通信,使上位机能够及时获取相关实验数据进行存储和处理。本设计应用于恒压供水系统中,对水泵的运行情况进行监控。     

PC机与西门子PLC在船舶电站自动化系统中的通信实现

介绍PC机与西门子PLC在船舶电站自动化系统中的通信方式,利用VB6.0中MSComm控件实现了PC与PLC的串行通信,该通信系统简单、可靠,有较高的使用价值.     

基于VB的PLC 1:N网络监控系统

本文对三菱FX系列PLC 1N网络的构成进行了研究,阐述了1N网络监控系统的硬件组成及上住机(PC)和下位机(PLC)之间串行通讯的方法,具体分析了通讯协议并给出了基于VB设计的通讯中数据发送的代码.     

基于PC和PLC的机械手控制系统设计

本文介绍了基于VB语言环境,采用MSComm通讯控件和RS-232通讯协议实现PC与西门子S7-200 PLC之间的通讯方法,并说明了这种通讯方式在机械手控制系统中的具体应用.重点叙述了PLC在自由通讯口模式下几个特殊存储器和VB串行通讯控件属性设置,给出了PLC实现数据接收与发送的具体编程方法.     

VB6．0环境下三菱FX系列PLC与上位机的串行通信

利用上位机来监控可编程控制器的通讯技术是现代工业控制中的常用技术。以PC机为上位机,PLC为下位机,针对三菱FX系列PLC与上位机之间的通讯协议,给出了利用VB6．0实现上位机与PLC串行通信的详细设计流程。试验结果表明,这种串行通信方法,传输数据准确、简单、移植性强。     

基于MX Component的PC-PLC通讯设计

通过PC机的COM口,应用三菱MXComponent软件包实现PC-PLC的通讯,在VB6.0平台下通过添加ActEasyIF控件,编写了上位机监控系统,可使PC机通过通讯口直接对PLC的软设备进行读/写、强制置/复操作。     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

基于QTE的蒙古文显示机制研究与实现

蒙古语言是中国蒙古族使用的通用语言,由于蒙古文区别于其他文字的书写方式和其自身变形机制等特点,在很多通用的文字处理引擎中都不被支持。在嵌入式产品开发与应用领域中Linux加QTE已经成为流行方式。该文给出了一种在QTE环境上实现基于标准Unicode的蒙古文点阵显示和变形算法, 并自定义了支持蒙古文的QTE组件,扩展了QTE功能,为在Linux加QTE方式的嵌入式体系结构中处理蒙古文提供了一种解决方法。     

基于AD9626的模拟信号采集存储卡设计

自然界的绝大部分信号都是以模拟的形式存在,因此模拟信号的采集转换存储在数字时代十分关键。文章讨论了在雷达信号处理领域基于AD9626的AD采集存储卡的设计原理、硬件结构和程序设计与芯片配置等问题,为今后相关领域的研究提供了可参考的方案。     

A human-computer interface for non-computer specialists

The COM teleconferencing system was designed to be easy to use for both beginners and people with much computer experience. A number of design choices in organizing the human-computer interface were considered very carefully. These design problems are not unique for teleconferencing applications, but will appear in many other developments of human-computer interfaces for non-computer specialists. This report discusses naming conventions, menu format, user commands, help facility and the treatment of ‘type ahead’ from the users.     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

Call for papers Special issue on Modeling and control technologies for civil,energy,and power systems

正The control of civil,energy,and power systems presents significant new challenges for modeling and control theory.The purpose of this special issue is to provide a forum for researchers and practical engineers to discuss the recent advances in modeling and control technology development for civil,energy,and power systems.Prospective authors are invited to submit their original contributions with the focus on theory or applications of modeling,control     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate and promote academic exchange between Chinese and foreign scientists everywhere.