浅谈几种矿山变电站无功补偿技术

文章介绍了3种应用于矿山变电站的无功补偿技术,分析了这3种技术的工作原理及其优缺点,并给出了相应的电路图。     

3D打印技术及应用

3D打印技术是一项快速发展的技术,该文首先介绍了几种快速成型技术,然后分析了3D打印技术的优势和应用前景,并分析了存在的问题。     

试析Java转化网页为PDF文档技术

介绍了iText、PD4ML、PDFCreater 3种Java转化网页文件为PDF文档的技术方案,分析了技术方案的相关知识、优缺点,给出了技术要点及关键代码,并对3种方案进行了对比分析.     

Web3D技术在远程教育中的应用

Web3D技术是虚拟现实技术的一种实现形式,在网络教育阶段采用具有交互功能的3D课件可大大提高学习效率,本文结合实际介绍了Cult3D技术以及基于Cult3D技术的多媒体课件的开发过程。     

Web3D技术在远程教育中的应用

Web3D技术是虚拟现实技术的一种实现形式，在网络教育阶段采用具有交互功能的3D课件可大大提高学习效率．本文结合实际介绍了Cult3D技术以及基于Cult3D技术的多媒体课件的开发过程。     

网络环境下三维虚拟展示技术的应用研究

该文重点研究了网络环境下的三维虚拟展示技术,分别探讨了伪三维与web3D技术各自的优点与不足,并对两种展示方式进行分析与比较。在伪三维技术中对比了三维动画技术、360度全景图像技术和Flash3D技术。在Web3D技术中对VRML、View-point、Cult3D和Java3D进行阐述和对比。最后指出了web环境下三维虚拟展示技术的发展方向。     

X3DOM技术在网络教育中的研究与应用

介绍了一种新的Web3D技术X3DOM,应用该技术可以较好的在网络中传输、显示3D内容,解决了网络教育中3D内容的显示问题,丰富了网络教育的媒体类型。     

3D打印技术在计算机建模教学中的应用

3D打印技术是一种检测模型设计效果与制作效果的辅助技术,近年来,在计算机建模教学中应用十分广泛。笔者分析了3D打印技术在计算机建模教学中的应用,应用3D打印技术可以提高计算机建模教学质量,并且激发了学生学习3D建模的兴趣。     

基于X3D技术的虚拟现实电子商务网站

本文给出了一种结合虚拟现实技术与三维视频技术的电子商务应用的开发过程,通过应用X3D技术,可以充分结合XML技术与VRML技术的优势,更好地被各种主流开发技术所支持,并且使传统的网站用户界面进入了三维的现实应用效果。由于X3D技术是一种发展中的技术,本文使用了Delone & McLean的IS success模型对该网站系统进行了评估,并且分析了X3D技术在现有条件下的相关不足,为该技术的改进和发展提供了有价值的信息和数据。     

基于Web的虚拟校园的构建及漫游系统的实现

虚拟现实技术是当今计算机科学研究的一个热点,将虚拟现实技术引入数字校园的研究中,为校园的规划和设计提供了一种全新的手段。该文介绍了一种基于3D和Webmax技术的虚拟环境的开发方法,即:用3DMAX构建三维模型、制作三维动画;用Webmax进行交互控制。并结合实际开发经验,对虚拟环境下3D建模、交互式漫游、碰撞检测、音效等技术进行了探讨。     

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