数字温度指示仪表远程自动检定系统设计

针对数字温度指示仪表检定效率低、人为误差大且难以溯源到更高等级标准的不足,提出一种基于Internet的远程自动检定系统.系统由设在计量实验室的远端上位机通过网络控制现场端运作,同时利用机器视觉技术采集被检仪表示数,再上传到上位机,并完成数据处理、分析.最终根据检定结果不确定度评定,给出被检仪器的检定结论,生成检定报告.系统可一次自动检定多台被检仪表,对提高数字温度指示仪表检定效率及实现溯源到更高等级标准具有参考价值.     

150mL活塞式液体微小流量计量标准装置的研究

针对现有液体流量计量标准装置测量范围的限制不能适应微流体计量的需求,研究开发了一种用于生物医药领域的150mL活塞式液体微小流量计量标准装置.介绍了该标准装置的结构、检定原理和检定过程;根据检定需求设计了一种基于LabVIEW平台和PLC的检定系统软硬件.利用LabVIEW平台设计上位机的检定程序,用于实现人机交互、检...     

活塞式输液泵分析仪检定装置的研究

为了解决国内很少有流量标准装置可以检定输液泵分析仪的问题,研制了一种基于主动活塞式的输液泵分析仪检定装置.阐述了检定装置的工作原理、结构,设计了集成数据采集和自动控制的系统.检定装置利用上位机控制工作流程,采集瞬时流量等信号.对输液泵分析仪在0.1～10 mL/h流量范围内进行了检定实验,证明分析仪的精度达到2％.同时分析了影响输液泵分析仪流量检定的不确定度因素,其扩展不确定为2.4％(k=2).结果表明:该装置具有良好的实用性和广阔的应用前景.     

并联式标准表法气体流量检定装置的设计

为提高气体流量计检定效率、扩大流量检定范围,提出了一种并联标准表法气体流量检定装置;装置采用2台DN50和2台DN150罗茨流量计作为标准表,能提供0.5~2000m~3/h的标准气体流量,实现多种流量计的快速检定;简述了装置的总体设计方案,详细分析了检定装置的流量计算模型,介绍了上位机检定程序和下位机电控系统,总结了流量调节实验;实际使用表明,该检定装置操作界面友好,检定过程简便高效,流量调节时间少于90s,调节误差1.5%以下,检定数据准确可靠。     

伺服控制放大技术在流速仪检定系统中的应用

为提高我国流速流量仪器的检定系统精度和自动化水平,对流速仪检定系统进行了改制。将伺服控制放大技术运用到流速仪检定系统,配合机械和计算机技术的应用,可提高流速仪检定车的性能参数。分析了应用伺服控制技术的新型流速仪检定车技术设计,系统组成,总结了系统的性能和指标,对比分析了新型流速仪检定车的比测应用情况,说明检定车完全实现设计构想,精确可靠。     

声学多普勒流速仪计量检定工作分析

从水量准确计量为切入点,根据声学多普勒流速仪推广使用中存在的计量检定问题,结合水利水文专业计量体系的促进和发展,论证了声学多普勒流速仪计量检定工作开展的必要性。从声学多普勒流速仪工作原理出发,探讨了利用水槽检定该类仪器的原理和方法,分析了检定方法的可行性。研究说明,利用现有水槽检定还存在一定难点,如何利用现有水槽,还需要进行试验。     

钟罩式气体流量标准装置自动检定系统的研究与设计

针对目前国内生产的钟罩装置多采用人工操作,在检测中需要测得被检表前和标准装置内部的温度、压力以及标定时间、体积流量、累计流量等一系列数据,再进行计算,其工作量大、数据多,且原有装置的同步控制由人工操作来保证,检定过程中存在效率低、操作繁琐等弊端,容易因人为的失误增大检定误差甚至产生错误,并且数据查询困难.因此,笔者研制了由ARM7微处理器为下位机和计算机为上位机的钟罩气体流量标准装置控制自动检定系统,以实现对检定过程的自动控制及数据处理.     

串行通信在压铸机控制中的应用

压铸机生产的压铸件广泛应用于汽车、仪表、航空等领域，现代化的生产要求多台PLC与计算机构成多级分布控制系统。以松下FP系列PLC为例，介绍了用VB6．0串行通信控件实现计算机与松下FP系列PLC之间的通信，说明了FP系列PLC的通信协议、硬件连接、通信格式以及开发的VB程序。在系统中，松下FP系列PLC作为下位控制机实现整个压铸过程动作的控制，工控机作为上位机实现压射力和压射速度曲线的实时采集和显示，以及PLC控制参数的修改和设定。实践表明，该方法简单易行，实用可靠。     

多用途pVTt气体流量装置控制系统的设计实现

针对p VTt法气体流量标准装置检定工作存在的效率问题,目前尚无能够满足不同流量范围音速喷嘴的检定装置。为此,设计了一套p VTt气体流量装置,并将正压法和负压法运用在这套装置中。采用西门子的PLC300作为系统的下位机,负责控制阀门与泵,并读取压力温度变送器的信号;采用Lab VIEW作为上位机监测系统,并生成数据报告。该套p VTt气体流量装置大大提高了原级气体仪表标定工作的效率,满足了不同流量范围音速喷嘴的检定工作要求,为气体流量装置研究提供了新的方向。     

基于VC和单片机的多通道锂电池检测系统

本文设计了一种多通道锂离子二次电池检测分析装置.该装置分为上位机和下位机两个部分,上位机用VC 编写控制程序;下位机由控制电路和通道板电路组成.上位机和8个控制电路(控制电路以AT89C52作为控制核心)之间通过RS-485进行通讯.每个控制电路控制8个通道的锂电池.从而实现了64个通道锂电池的同时检测.     

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.     

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.     

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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