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综述程控稳压稳流电源的发展状况,并介绍几种稳压稳流电源的基本原理及设计方法。在此基础上提出基于PIC16F84单片机及经典的线性反馈调整电路,提出一种可程控稳压稳流电源的设计方法,完成了原理图和PCB板的设计以及电路的调试与测试。经过测试表明,该系统具有可程控、输出电流大、输出电压范围广、电压电流稳定等特点,达到了设计预想要求。 相似文献
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本文介绍利用Visual Basic 6.0设计PCS-05型程控直流恒流电源控制软件,以达到控制该电流源输出用户所需各种电流方波信号. 相似文献
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飞机机载电源系统供电品质直接关系到飞机用电设备可靠工作和飞行安全,为此,2006年国际标准组织推出了新的机载电源标准ISO1540-2006;本文根据该标准要求,提出了一种机载电源的稳态和瞬态特性的测试的实用方法;建立了测量的数学模型;采用虚拟仪器技术,设计硬件测试平台,包括功率因数可调的大功率数字化程控负载和计算机数据采集系统;基于LabVIEW开发了测试软件;为满足暂态特性的测量要求和精度要求,采用了NI高速高精度数据采集卡,实现了较高的测量精度,综合测量误差小于0.5%,并在暂态测量中,考虑了负载接触器吸合时间;该测试系统可以用来检验恒频机载交流电源的特性是否符合国际标准要求,以保证飞行安全。 相似文献
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透射电子显微镜透镜稳流电源的研究 总被引:1,自引:0,他引:1
本文以物镜磁透镜稳流电源为例,介绍了透射电子显微镜透镜稳流电源的结构和工作原理.透镜稳流电源由前置高精度稳压电源模块、数模转换器、低漂移电压比较放大器、高精度恒温基准电压源、电流输出前置驱动、电流输出功率模块、基准电阻、输出电流检测模块等组成.通过检测基准电阻两端的电压并将其反馈到电压比较放大器形成对输出电流的闭环控制.达到对电流稳定度的要求.透镜稳流电源受计算机的控制,能接收稳流电流参数,并将电源的工作状态发送给计算机.实验结果表明该透镜稳流电源完全达到了设计指标,可以满足透射电子显微镜各级磁透镜的要求. 相似文献
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在真空管的排气系统中,需要对真空管管体加热,并对其灯丝等设备提供一定的电压和电流.为了配合计算机控制的排气系统,需要采用程控电源仪提供所需的电压.本设计中的程控电源仪是一台实用化的电压调节智能仪表,它控制电机调节自耦变压器,通过反馈控制使其输出电压稳定在一个宽范围变化的电压值.它通过RS-485与串行通信电路与上位机连接,并且具有电流测量、报警输出等扩展功能.实际应用表明,该电源仪设计合理,工作可靠,性能稳定. 相似文献
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设计了一款高精度、低纹波、稳定性高的程控直流电流源,它采用STM32F103微控制芯片作为整机的控制核心,设计上位机软件来实现对硬件系统的调控。硬件系统由双闭环结构组成,内环是由PI控制器构成电压串联负反馈,提高了输出电流的稳定性。外环则是通过A/D采样电路将实际电流值送入主控芯片,再根据相应控制算法重新调整D/A的输出,提高了输出电流的精度。测试结果表明,电流源的输出电流稳定度高达0.003%,精度达0.01%,最大输出电流高达25 A,适用于电力部门、计量院等对电源精度要求高的场合。 相似文献
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基于PLC的机载电子设备ATE电源控制系统 总被引:1,自引:0,他引:1
为了实现对某型机载电子设备ATE系统测试资源的有效管理,满足按照专业适配器分别自动程控上电的要求,采用了一种PLC和上位计算机组合控制模式,实现了PLC电源控制系统多路开关量TD按钮的单独控制和上位计算机的组态监控,并实现了两种控制模式的无痕迹切换;在此基础上,还设计实现了系统的电压、电流报警和系统内温湿度的空调控制;实践证明,实现的ATE电源控制系统,减少了资源的不合理使用,提高了资源的利用效率,提高了系统运行的可靠性。 相似文献
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张涛 《计算机测量与控制》2015,23(1):86-89
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. 相似文献
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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. 相似文献
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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. 相似文献
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《Information & Management》2016,53(6):787-802
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. 相似文献
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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. 相似文献
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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. 相似文献
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《浙江大学学报:C卷英文版》2014,(11)
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 相似文献
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Zhao-hui WU 《浙江大学学报:C卷英文版》2014,(10)
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 相似文献
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《浙江大学学报:C卷英文版》2014,(10)
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 相似文献