板状结构可变边界热振耦合试验系统研制

针对板状结构存在不同边界约束以及恶劣高温环境,研制了变边界高温试验模态系统,为板状结构在高温振动耦合环境下的测量提供一套低成本、可变边界试验系统。该试验系统采用虚拟仪器LabVIEW对石英灯阵进行温度控制,自行研制耐高温陶瓷导杆引伸装置将板状结构上的振动信号传递至非高温区域,使用激振器对板状结构进行激励,通过常温加速度传感器测量其响应信号,使用时-频联合技术对测量的模态数据进行参数识别获得板状结构的模态参数。以45号钢板为测试样件,得到其在室温下不同边界的模态参数;并在单边约束下对45号钢板进行500℃高温振动耦合实验,得出其模态参数。该试验系统可为板状结构在变边界高温振动耦合环境下的安全设计提供可靠依据。     

煤田火区高温氧化燃烧特性参数测试装置研发

针对煤田火区高温贫氧氧化燃烧特点、现有煤自燃特性参数测试装置的特点和不足,研发了一种煤田火区氧化燃烧特性参数测试装置,并对该装置进行了温控性能检测和煤田火区燃烧特性实验。实验结果表明,该装置温控性能良好,能够测试不同氧气浓度条件下,以不同升温速率或升温方式模拟的煤田火区燃烧特性参数。     

高温反应装置表面温度传感器安装结构及安装方法

一种高温反应装置表面温度传感器的安装结构,传感器紧贴高温反应装置表面,传感器外部依次设有一具有导热作用的导热层,一具有保温作用的保温层,以及一个压板结构,固定在高温反应装置表面,具有多点紧固作用,用于压紧传感器、导热层和保温层;导热层和保温层为独立结构或一体化结构。本发明能很好地将高温反应装置表面热量传导到表面温度传感器上,并对其进行保温,从而降低高温反应装置表面温度传感器的温度测量误差,提高高温反应装置表面温度传感器的温度探测精度。     

真空热处理炉检测装置改造设计

为了提高计量工作效率,杜绝真空炉密封性隐患,有效保证热处理产品质量,从检测装置设计、密封性分析、测试系统选择、温度均匀性和压升率测试方法等方面给出了具体的实施方案.详细分析了两种炉温检测装置的优缺点及法兰密封技术.实际测试结果分析表明,对法兰测温装置的改造,不仅满足了在不影响生产的条件下对真空炉进行温度均匀性测试的要求,而且解决了真空炉工艺要求的每周系统精度校验问题.     

热电偶检定炉炉温模型参考自适应控制的研究

热电偶校检定炉在对热偶进行高温点的校验时,炉温难于稳定,主要原因在于控高温时加热时间较长环境温度产生较大变化,从而造成检定炉加热模型产生时变,导致控制器效果明显变差,本文利用模型参考自适应控制方法在线调整PID控制器参数以适应环境温度变化而造成的加热炉模型时变,试验结果表明该方法适应性良好,从而为热电偶检定炉的温度控制提供了新的方法。     

金属波纹管高温振动试验系统研制

为解决金属波纹管的高温振动特性测试难题,研制了一套低成本、温度连续可调的金属波纹管高温振动试验系统;该试验系统以弧形石英灯阵为辐射加热装置并采用LabVIEW对波纹管进行精确温度控制,通过电磁激振器对金属波纹管施加轴向和径向的外部激励,由动态加速度传感器获取振动响应信号,经数据采集器进行实时采集存储,获得波纹管振动响应;以DN108不锈钢波纹管为试验样件,测试其在不同温度的频响曲线,试验证明,该系统可稳定、可靠地获取波纹管高温振动特性.     

增强型等离子化学气象沉积炉均匀布气研究

研究感应式射频等离子体技术,为提高离化率,利用流体力学的相关数值计算方法, 对增强型等离子化学气象沉积(Plasma Enhanced Chemical Vapor Deposition ,PECVD)设备的布气系统进行理论分析,得到平板布气装置中压力与孔径的关系.为了实现根据PECVD设备最大面积的均匀性布气,根据PECVD设备中的压力分布,优化现有的布气装置结构参数,以实现孔径补偿气流的效果.并结合专用的CFD软件对上述不同结构中的气流进行仿真,验证所优化的布气装置的合理性.用到现有的设备当中测试,提高了装备的均匀布气效果.     

基于MEMS热电堆传感器的高温测量技术

为了拓宽MEMS热电堆传感器的温度测量范围,实现高温测量,根据MEMS热电堆传感器的原理,设计完成了A2TPMB34型MEMS热电堆传感器静态与动态标定装置,通过试验得到标定结果;同时,提供了基于MEMS热电堆传感器实现瞬态高温测试的技术方案和实现手段,并对其关键部分一红外衰减片性能进行了分析和讨论。     

高温应变测试方法与测试系统开发

高温应变的测试往往是工程上的一个难点,高温会对传感器、测试仪器以及测试数据带来诸多的影响,需要采取有针对性的措施来保证测试方案的可行性和测试数据的准确性。通过实验分析高温对应变测试过程产生的各种影响,就高温应变计的选型和参数修正、高温条件下的温度补偿,以及测试数据的处理进行了详细的分析讨论。并针对这一过程开发了配套测试系统,通过实测某高温退火炉炉壁工作过程的应变情况,得到了准确的温度-应变曲线和炉壁的应力分布情况,在高炉的分析检测中取得了较好的效果,对一般的高温应变电测也具有很好的适用性。     

LabVIEW平台上的温度自动检测装置研究

针对油田开发的技术需求,分析了温度检测装置的总体结构,探讨了温度检测装置系统的编写程序及功能原理,构建了基于虚拟仪器Lab VIEW的温度自动检测装置系统。根据相关信号参数,对比了现有的温度检测装置的特点。在油田开发作业中,温度检测技术的提高不仅关系到油田生产活动,更是推动其生产效率提升的重要基石。研究表明,当油田的周边环境温度发生改变时,晶体参数就会发生改变,使得静态工作点变得不稳定,严重时还会导致电路停止正常的工作。结合Lab VIEW技术,对温度检测装置进行系统测试后,证明了该新型温度检测装置能够实现多台温度仪表的同时检测、多检测点不间断检测,以及温度仪表检测的自动化和对电信号的采集。     

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