基于蓝牙和互联网技术的BLDC电机远程控制系统

为了满足远程控制的需求,解决现有控制方案的不足,介绍了一种基于蓝牙和互联网技术的无刷直流(BLDC)电机远程控制系统。使用控制器集成蓝牙模块,通过蓝牙通信将控制器与服务器连接。客户端与服务器通过TCP协议实现网络通信。服务器作为互联网设计的通信节点,实行客户端与控制器连接,完成无刷直流电机的远程控制系统。文章从硬件和软件两方面描述了该系统的实现。     

无刷直流电机模糊自适应PID控制研究与仿真

针对传统的PID控制方式在对无刷直流电机系统控制时,存在精度低、抗干扰能力弱等不足,提出一种基于参数自适应模糊PID集成控制策略。首先,分析了无刷直流电机的数学模型,建立了基于双闭环调速系统的无刷直流电机控制系统模型,并对无刷直流电机双闭环系统转速进行模糊PID控制;然后,详细分析了建立该模糊自适应PID控制器的设计方法,提出一种优化模糊算子的优化方法,并运用仿真软件Matlab/Simulink实现了系统的设计和仿真;最后,在相同环境下,对比传统PID控制和模糊自适应PID集成控制两种控制策略的仿真结果。仿真结果表明,模糊自适应PID集成控制算法能使无刷直流电机双闭环控制系统具有更好的动、静态性能及较强的自适应能力。     

基于F28335的小型化无刷直流电机伺服控制器的开发

介绍了一种小型化高性能无刷直流电机伺服控制器的软硬件设计及实现.硬件上采用TMS320F28335型DSP为核心处理器,设计了三相全控桥式功率驱动电路和完成欠压、过流检测等检测保护电路.能通过CAN总线实现与上位机的高速通信并进行实时数据交换,应用PID算法实现电机的位置闭环和转速闭环数字调节.实验结果表明控制器基本满足200W以内的中小型无刷直流电机驱动控制需求.     

基于S-函数的无刷直流电机系统建模研究

本文在分析无刷直流电机系统数学模型的基础上,提出了无刷直流电机控制系统仿真建模的新方法。在Matlab/Simulink中,通过S-函数独特的结构,建立独立的功能模块,如电动机本体模块、反电动势产生模块、速度PI控制模块、电流PI控制模块等,再进行功能模块的有机整合,搭建无刷直流电机控制系统快速高效的仿真模型。该方法成功地应用于电动车驱动系统的设计仿真。     

基于GPRS的无刷直流电机控制系统设计

设计开发了基于无线通信的远程控制系统,无线通信采用的是GPRS技术。GPRS模块的MC53i和DSPTMS320F2812进行双向通信,而DSPTMS320F2812产生PWM波形和开关量信号控制直流电机L298N最终实现对无刷直流电机的转速控制(PWM)和正反控制(开关量信号)。     

基于STM32的无刷直流电机控制驱动器硬件设计

设计了基于STM32VET6单片机和SA306功率驱动模块的永磁无刷直流电机控制驱动器,详细介绍了组成系统的各部分接口电路.该硬件系统能够进行扩展通信,具有电流保护和温度保护能力,适用于中小负载永磁无刷直流电机的控制.该控制驱动器成本低廉且容易实现,经过多次实验验证,能够长时间安全可靠地运行.     

基于DSP的无刷直流电机测试系统的设计

介绍了一种适合于无刷直流电机的自动测试系统.该系统以TI公司生产的DSP控制器TMS320LF2407A为核心控制芯片,充分利用DSP丰富的内部外设模块,设计了一种无刷直流电机的检测实验平台.同时介绍了平台的软、硬件设计方法以及上位机PC软件编程技术和下位机DSP软件编程技术.友好的人机界面为解决电机的参数调试提供了良好的途径.试验表明,该平台能满足无刷直流电机的检测需要.     

基于IDP卫星通信模块的远洋船舶实时监控系统

针对远洋中无GPRS信号不能进行无线通信的问题,设计了以STM32F103VCT6单片机与IDP卫星通信模块为平台的远洋船舶实时监控系统。本系统具有高精准度、实时性强、全天候监控等特点。给出了系统的工作原理、硬件设计与软件实现方法,详细分析了中央控制模块、GPS定位信息采集模块、无线通信模块。实验结果验证了采用STM32F103VCT6单片机与IDP卫星通信模块设计远洋船舶监控系统的可行性。通过该系统,可实时监控远洋船舶的地理位置信息以及其他信息,最大限度地确保远洋船舶航运中的安全。     

基于广义预测PI的无刷直流电机速度控制研究

无刷直流电机(BLDCM,brushless DC motor)转速控制是电机控制中的重要问题之一.分析了无刷直流电机的工作原理,提出了广义预测优化PI的控制算法,采用数学模型对控制器的设计进行了理论推导.通过基于DSP的无刷直流电机实验平台进行广义预测PI控制算法实验验证,结果表明此控制算法能显著提高系统的性能,是有效可行的.     

无刷直流电机双闭环控制系统的建模与仿真

在分析无刷直流电机数学模型的基础上,提出一种无刷直流电机控制系统仿真建模的新方法。在Matlab／Simulink中按功能进行模块化建模。用M文件和S函数来缟写功能模块,实现电流滞环和转速单神经元PID控制的双闭调速系统仿真。仿真结果与理论分析一致,验证了该控制系统设计的合理性。此仿真模型可以验证各种控制算法,为无刷直流电机控制系统的分析和设计提供有效的途径。     

Call for Papers The 6^th International Conference on Grid and Cooperative Computing

Recent years have seen rapid advances in various grid-related technologies, middleware, and applications. The GCC conference has become one of the largest scientific events worldwide in grid and cooperative computing. The 6th international conference on grid and cooperative computing (GCC2007) Sponsored by China Computer Federation (CCF),Institute of Computing Technology, Chinese Academy of Sciences (ICT) and Xinjiang University ,and in Cooperation with IEEE Computer Soceity ,is to be held from August 16 to 18, 2007 in Urumchi, Xinjiang, China.     

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.     

法律信息库系统

本文分析了法律数据库的结构和特点，介绍了采用面向对象设计方法和超文本数据库技术开发和实现法律信息库系统将作为重要网络资源之一为不同用户进行法律咨询服务。     

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.     

International Journal of Automation and Computing Table of Contents

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Information for authors

正SCIENCE CHINA Information Sciences(Sci China Inf Sci),cosponsored by the Chinese Academy of Sciences and the National Natural Science Foundation of China,and published by Science China Press,is committed to publishing highquality,original results of both basic and applied research in all areas of information sciences,including computer science and technology;systems science,control science and engineering(published in Issues with odd numbers);information and communication engineering;electronic science and technology(published in Issues with even numbers).Sci China Inf Sci is published monthly in both print and electronic forms.It is indexed by Academic OneFile,Astrophysics Data System(ADS),CSA,Cabells,Current Contents/Engineering,Computing and Technology,DBLP,Digital Mathematics Registry,Earthquake Engineering Abstracts,Engineering Index,Engineered Materials Abstracts,Gale,Google,INSPEC,Journal Citation Reports/Science Edition,Mathematical Reviews,OCLC,ProQuest,SCOPUS,Science Citation Index Expanded,Summon by Serial Solutions,VINITI,Zentralblatt MATH.     

Erratum to: Fast global kernel fuzzy c-means clustering algorithm for consonant/vowel segmentation of speech signal

正Erratum to:J Zhejiang Univ-Sci C(ComputElectron)2014 15(7):551-563doi:10.1631/jzus.C1300320The original version of this article unfortunately contained mistakes.Algorithm 6 should be as follows:Algorithm 6 FGKFCM-F clustering Input:(1)X={x_1,x_2,…,x_N},,x_iR~d,i=1,2,…,N,the dataset;(2)C,1C≤N,the number of clusters;(3)ε0,the stopping criterion;     

Journal of Zhejiang University-SCIENCE C (Computers & Electronics) Total contents

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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.