基于LabWindows/CVI的飞机电负载系统设计

在飞机试飞定型过程中,为了验证飞机的电源系统、APU电源系统的功能和性能在满载及超载情况下是否满足有关设计要求,需要研制电负载系统,提取并消耗发电机的剩余功率。系统由控制子系统、负载子系统和补水排水子系统3个模块组成。以PLC为下位机,上位机以LabWindows/CVI为开发平台,配合高速数据采集卡组成的控制子系统具有高可靠性、高采集精度、高控制响应能力等特点。实验表明,该系统运行稳定可靠,控制效率高,并在试飞中获得了良好的效果。     

A320飞机电源检测与负载配电系统设计

A320飞机电源检测和负载配电系统由飞机电源检测部分和负载配电部分组成。飞机电源检测部分采用STM32F4系列单片机,完成对输入交流电压、电流、频率等参数的检测、逻辑控制以及电网保护等;负载配电部分虚拟实际飞行阶段、飞行状态,通过分析负载需求,完成飞机负载配电控制和状态监控。所设计的系统可以实现飞机电源系统运行动态模拟,具备真实性强,可操作性高,可维护性好等特点,不仅可作为航空维修教学训练平台,还可为电源系统附件维修提供维修方案,应用前景良好。     

基于CAN总线的飞机重心自动调节系统设计

在飞机试飞过程中,为了验证不同重心状态下飞机的可操作性和稳定性,提出了基于DSP的CAN总线重心自动调节系统设计方案.该系统的设计利用通信速度较快的CAN总线技术,提高了系统通信的稳定性和效率,同时减少了系统的布线和负载.实验表明,飞机重心自动调节系统达到了飞机试飞的要求,为以后的飞机试飞打下了很好的基础.     

飞机三级式发电系统建模与仿真

在飞机电源系统的优化设计中,飞机发电系统为机载用电设备正常工作提供条件,而在负载发生突变情况下能否快速做出反应以保证供电质量和可靠性能,直接影响到飞机的性能.为保证可靠性,分析了飞机三级发电系统组成结构和工作原理,建立飞机发电系统仿真模型的基础上,设计了用于调节电能质量的控制器——调压器,在MATLAB/Simulink环境下建立整个系统的模型,并对飞机发电系统部分进行动态仿真.仿真结果表明,能较真实的反应飞机电源系统的动、静态性能,证明所建立的模型是正确的,采用的方法是可行的,为飞机电源系统的设计提供有效的研究手段与参考依据.     

基于模糊控制下的飞机电源系统过载保护研究

当飞机发电机出现过载时，电源系统中的过载保护子系统将断开一些负载，以保证发电机安全工作，为提高电源系统工作稳定性，降低电源波对用电设备造成不利影响，需采取反延时通断控制技术进行过载保护控制，要有效实现反延时通为控制，关键问题就是如何确定出最佳延时时间，本文通过采取模糊控制理论和技术来确定最佳延时时间，以提高电源系统供电品质和眨长发电机使用寿命，使得电源系统过载保护控制更具有智能性、先进性。     

飞机自动配电管理系统设计

飞机配电系统是现代飞机的一个十分重要组成郜分,做好这项研究工作可以提高飞机的供电质量、飞机完成任务的概率以及飞机自身的安全性,减少体积重量及全周期费用,使我国飞机配电技术上一个新台阶;对某型飞机电气负载自动管理技术进行了系统研究,提出了一种电气负载管理优先级设置方法,建立了电气负载的控制方程和电气负载的电源请求方程;系统试验表明采用负载自动管理技术大大提高了飞机供电系统的可靠性和可维护性.     

基于LabVIEW的飞机电源地面试验测试系统

为了检验飞机电源的供电品质是否达到国家标准,设计了一套基于虚拟仪器技术的通用飞机电源地面测试系统。本文介绍了系统的硬件组成和软件的实现。该系统在中国试飞院运行,效果良好。     

飞机电气负载管理系统设计

飞机配电系统是现代飞机一个十分重要的组成部分,做好这项研究工作可以提高飞机的供电质量、飞机完成任务的概率以及飞机自身的安全性,减少体积重量及全周期费用,使我国飞机配电技术上一个新台阶.对X型飞机电气负载自动管理技术进行了系统研究,提出了一种电气负载管理优先级设置方法,建立了电气负载的控制方程和电气负载的电源请求方程.系统试验表明采用负载自动管理技术大大提高了飞机供电系统的可靠性和可维护性.     

机载网络化测试系统框架设计技术研究

随着现代飞机的不断发展,尤其是大型飞机的发展,飞行试验要求测试的参数种类和数量越来越多,数据传输量越来越大.为了满足新一代飞机试飞快速发展的测试需求,构建网络化机载测试系统,实现测试系统间数据的海量传输,各个子系统之间的交互以及网络数据融合是一个发展的趋势.但是在一个大型的机载网络测试系统设计中,如何考虑测试系统测试参数的实时性、同步性和可靠性是试飞测试工程师将面临的全新挑战.     

飞机三级发电机的建模与仿真

研究飞机电源系统供电优化问题,飞机交流发电系统多采用三级式无刷交流同步发电机,由永磁发电机、交流励磁机和主发电机组成.为了仿真飞机三级发电机,在介绍三级同步发电机结构的基础上,通过派克变换在dq0坐标系下,建立三级发电机的动态数学模型,在Saber软件平台下使用MAST语言编写同步发电机模型,结合调压器及电气负载得到三级发电机的部分动态仿真结果,仿真结果能够很好地显示三级发电机对不同负载的响应,证明了模型的正确性,为飞机电源系统的设计提供了一个有效的工具.     

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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