基于PLC的步进电机运动控制关键技术研究

本文介绍采用步进电机的运动控制技术9设计了基于西门子PLC的运动控制系统。该系统采用闭环控制方式，并采用西门子PLC的单轴步进电机定位模块FM353以简化系统硬件结构，提高整个系统的品质，包括控制精度、稳定性和可靠性等。此外，对步进电机的变速控制也作了分析和设计。     

基于TMS320F240的交流变频调速系统

使用TI公司的电机控制专用芯片DSP-TMS320F240设计了一个交流电机变频调速系统，针对设计的几个主要部分，详细介绍了DSP结构特点及其在所设计的系统中的应用，并给出系统部分程序框图的设计。     

Halbach电机的基本原理及其有限元辅助设计

Halbach电机是一种新型的永磁电机，其特殊永磁体结构不仅可以增加气隙磁通，而且还可以削弱转子轭部磁通密度．这样不仅可以提高电机的功率密度，而且还可以降低电机的体积和成本。文中利用有限元对Halbach电机设计进行了深入研究。     

基于单片机的步进电机控制

提出了一种基于单片机控制电机旋转方向、转速及步距数控制的方案，分析了电机的结构和原理，讨论了系统硬件和软件的设计，并已成功应用。     

用微机和单片机控制步进电机的走动

本文主要介绍了在ｗｉｎｄｏｗｓ平台下实现对步进电机的走动控制的一个实际系统。本系统利用单片机控制步进电机，减少对ＣＰＵ资源的占用；步进电机的转速和步长，是在ｗｉｎｄｏｗｓ下改变，控制操作只需要鼠标即可。软件编程中使用了“操作教＋操作码”的结构，使得程序简练而又应用。     

基于L297/L298芯片步进电机的单片机控制

在分析了步进电机驱动芯片L297/L298的性能、结构的基础上,结合AT89C52单片机,介绍实现驱动步进电机的一种简单方法.文中给出了控制原理图。实测表明,利用该方法设计的步进电机驱动系统具有硬件结构简单、软件编程容易和价格低廉的特点。     

基于单片机的电机测速系统设计

电机测速系统在当今的科技领域有着非常广泛的应用,目前对该系统的设计也成为了相关领域的热门话题。本文以单片机为核心基础,对电机测速系统的结构进行了了解。并分析系统设计中的硬件设计以及软件设计要点,最终设计出基于单片机的合格电机测速系统,希望能为多样化、准确、稳定的电机测速工作提供参考。     

多自由度运动计算机控制系统的设计

本文介绍了由计算机对步进电机控制从而实现多自由度运动的系统的设计。同时详细介绍了系统中的结构组成、软件的应用和步进电机的控制。该控制系统操作界面友好、简单,动态响应快,系统精度高。     

多自由度运动计算机控制系统的设计

本文介绍了由计算机对步进电机控制从而实现多自由度运动的系统的设计.同时详细介绍了系统中的结构组成、软件的应用和步进电机的控制.该控制系统操作界面友好、简单,动态响应快,系统精度高.     

探究单片机下的电机运动控制系统设计

针对电机的运动控制需求,本文利用AT89C51单片机完成了一种电机运动控制系统设计.而该系统由复位电路、时钟电路、按键控制电路和驱动电路等多个结构组成,能够实现对电机运动的精准控制,并且能够满足系统的各种应用需求.     

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.     

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.     

A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.     

The Distributed Time-Triggered Simulation Scheme: Core Principles and Supporting Execution Engine

Distributed real-time simulation is a young technology field but its practice is under increasing demands. In recent years the author and his collaborators have been establishing a new approach called the distributed time-triggered simulation (DTS) scheme which is conceptually simple and easy to use but widely applicable. The concept was initiated in the course of developing a new-generation object-oriented real-time programming scheme called the time-triggered message-triggered object (TMO) programming scheme. Some fundamental issues inherent in distributed real-time simulation that were learned during recent experimental studies are discussed along with some approaches for resolving the issues. An execution engine developed to support both the TMOs engaged in control computation and the TMOs engaged in DTS is also discussed along with its possible extensions that will enable significantly larger-scale DTSs.     

Software-Konfigurationsmanagement in großen Softwareprojekten

Zusammenfassung Mit zunehmender Größe der Softwaresysteme verschärfen sich die für die Software-Herstellung typischen Probleme: Beherrschen großer Objektmengen, Erhalten der Systemkonsistenz, Kontrolle der ständigen Änderungseinflüsse und Gewährleisten einer langen Lebensdauer. Die Disziplin Konfigurationsmanagement bildet den methodischen Ansatz, diese Probleme besser zu beherrschen. Software-Konfigurationsmanagement faßt die Herstellung von Softwaresystemen als eine Abfolge von kontrollierten Änderungen an gesicherten Zwischen- und Endergebnissen auf. Dargestellt werden die Objekte und Funktionen des Software-Konfigurationsmanagements sowie die hierfür in großen Software-Projekten benötigten Methoden, Instanzen und Hilfsmittel.     

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     

Editorial:Brain-machine interface(BMI) and cyborg intelligence

正Brain-machine interfaces(BMIs)aim at building a direct communication pathway between the brain and an external device,and represent an area of research where significant progress has been made during the past decade.Based on BMIs,mind information can be read out by neural signals to 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     

SCIENCE CHINA Information Sciences SUBJECT INDEX TO VOLUME 57(2014)

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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