综合传动装置起动扭矩测试试验研究

低温环境起动性能是表征车辆动力性能的一项重要指标;对液力机械传动车辆而言,由于综合传动装置自身技术特点,改善车辆起动性能除应当考虑发动机自身起动阻力外,还应当考虑综合传动装置的起动阻力;在系统分析综合传动装置技术特点和功率流向的基础上,总结了发动机起动过程的主要特征,提出采用稳态试验与动态试验相结合的台架试验方法进行综合传动装置起动扭矩测试;以某高速履带车辆为研究对象,进行了综合传动装置起动扭矩测试;试验结果表明,传动油温的变化和各类油泵的功率消耗是决定综合传动装置起动扭矩大小的关键因素,为改进车辆总体设计和提高车辆起动性能提供了依据.     

无线与存储融合的传动轴扭矩测试系统设计

存储测试非常适合于旋转轴扭矩测试,但是存储测试需事后回收处理,无法现场观测数据,且参数设置固定。针对上述问题,结合履带式车辆传动轴扭矩测试情况,以存储测试为基础结合Zigbee无线技术,设计了基于LabVIEW上位机控制的无线存储测试系统,利用Zigbee无线网络实现无线触发和多次重触发,并回传测试开始后的少量数据,根据回传数据调整测试单元的参数。实验结果表明该测试系统存储测试与无线技术能有效结合,充分发挥各自的技术优势,提高了测试效率和数据的可靠性,具有良好的应用前景。     

一种基于Zigbee技术的病房监护系统的设计

介绍了一种基于Zigbee技术的病房监护系统设计.首先分析了Zigbee网络拓朴结构,然后介绍了一种基于Zigbee的无线传感网络系统架构,采用LC2480无线网络模块实现了无线终端的设计,给出了相应的软件设计流程图,最后进行了模拟测试研究.该系统在医院内和医院间的智能医疗监护方面有着广泛的应用前景.     

汽车安全带卷簧扭矩测试系统软件的设计与实现

扭矩性能是汽车安全带卷簧最重要性能之一;为了准确,直观测试汽车安全带卷簧的扭矩性能,应用MFC文档视图技术开发汽车安全带卷簧扭矩测试系统软件;软件基于VC6.0开发环境,采用多线程技术实现了数据采集与控制模块;利用MFC类库开发了数据波形与监测交互模块,应用COM技术开发了数据报表模块,结合卷簧扭矩测试硬件对软件功能作了测试;结果表明,测试精度符合要求,达到0.001 N·m;开发的软件满足汽车安全带卷簧扭矩测试的要求,具有较高的测试精度,较好的交互功能和一定的应用前景.     

一体化气压测试系统的设计

采用硅压阻式绝压型压力传感器SM5420、精密传感信号调理器MAX1452和微处理器C8051F410,共同构成一体化气压测试系统。利用串口通信模块将被测气压值一路通过LCD液晶显示屏显示,另一路通过RS232通信接口发送给上位机。实现了被测气压实时准确读取和分析处理的功能。通过标准压力泵对其进行静态标定得出其静态特性指标。该系统具有:体积小、频率响应高、精度高、灵敏高等优点。     

基于ZigBee的无线传感器网络平台

介绍了基于Zigbee的无线传感器网络,采用Atmegal28L和CC2420芯片设计实现了,一个基于Zigbee的无线传感器网络平台,详细阐述了系统架构设计,微控制器模块和射频模块硬件设计以及基于TinyOS的软件设计.实验测试该平台工作稳定可靠.     

基于Zigbee的车辆身份识别系统的研究与实现

提出了一种基于Zigbee技术的车辆身份合法性识别系统在城市中运用的系统方案,详细介绍并分析了Zigbee技术规范,结合现代数字无线通信技术,通过Zigbee通信收发模块,实现了实时数据的采集,监控查询,车辆控制以及与系统现有各种网络的信息之间的数据融合,系统的Zigbee技术应用具有低成本,低功耗,高稳定性、高灵活性和可扩展性等特点,可极大地提高城市车辆运行的效率,有效地解决了城市交通系统中车辆身份识别的难题.     

物联网终端性能与网络协议综合测试解决方案

随着物联网和网络协议技术的广泛应用,相应的测试需求增长愈加猛烈。为了测试采用Wifi/Bluetooth/Zigbee/ IPv6 以太网等协议开发的设备或产品是否符合其相应协议标准,从而达到实现之间的一致性与互通性,对Wifi/Bluetooth/Zigbee/ IPv6以太网等协议的测试规范进行了研究,分析了各个协议的测试项,介绍了基于NI的PXIe-5840射频矢量收发模块和以太网协议测试等自研成熟模块及软件算法搭建的物联网综合测试仪,该综测仪采用了PXIe总线架构,集仪器测试、协议测试和流程测试于一体的结构设计,经实际应用可满足Wifi/Bluetooth/Zigbee/ IPv6以太网等协议的物理层射频性能和协议层性能的测试需求。     

基于Zigbee技术的无线车载油位采集模块的实现

该文从Zigbee技术在无线个人区域网中的应用出发,对基于Zigbee技术的车载油压采集模块进行了介绍。详细介绍了采集模块的软硬件设计方案以及使用到的几款主要的芯片的性能和参数,并针对车辆油压采集特殊要求提出了设计时需要注意的几个方面。同时重点分析了采集模块硬件结构和软件设计。     

微扭矩数据采集与分析系统

针对专用的汽车装饰配件扭矩测试设备,提出了一种使用Matlab DAQ工具箱和GUI模块来快速构建数据采集与分析系统的方法;使用研华的多功能卡PCI1711来实现数据的采集与电机的控制,采用Matlab内置的GUI模块来构建用户操作界面;首先叙述微扭矩测量系统硬件组成要素与采集系统基本工作原理,接着阐述采集系统软件操作流程,然后详细叙述了Matlab DAQ工具箱中模拟量输入与输出、数字量输入与输出幽数的实现方法,最后,结合GUI模块来构建一个实用化的微扭矩测量系统;测试结果表明,该方法是有效的.     

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