水情信息移动查询系统的设计与实现

为了方便快捷地获取实时水情信息,对水情信息移动查询系统进行了设计开发.该系统客户端基于开源的嵌入式Linux和Qt/Embcdded开发GIS查询软件,经GPRS移动接入GIS应用服务器,采用Oracle9i数据库统一管理服务器端空间数据和水情数据,GIS应用服务器以JDBC方式连接数据库,实现空间分析和水情信息查询,并以Socket方式将结果传回客户移动终端.应用实例表明了使用终端的GIS软件实现实时水情信息移动查询的可行性.     

基于基站的移动终端定位的研究及应用

随着移动终端、3G网络的快速发展与结合,公众对于获取位置信息的需求迅速增长.基于基站的定位系统的发展是非常有必要的.针对移动网络原理、Android技术进行研究后,提出通过定位软件获取GSM网络中移动终端用户的位置信息,在服务器端对数据保存及处理,最后在电子地图的支持下,为用户提供一种定位服务.经过测试,这种定位服务不仅能给普通群体提供定位和轨迹查询服务,更能免费为老人、孩子等弱势群体的人身安全提供保障.     

基于ARM/GPRS的宿舍信息发送系统

针对宿舍卫生和违规信息及时发送的需求,设计并实现了基于GPRS及Synchronization Services for ADO.NET同步技术的宿舍信息发送系统.该系统由服务器端、移动终端（采用基于ARM9的S3C2440微处理器）、GPRS网络和手机接收终端组成.ARM控制器通过串口向GPRS模块发送AT指令,将宿舍相关信息以短信形式发送至手机端,移动终端通过基于服务的同步技术实现与服务器端信息的同步.     

移动教务信息查询系统的设计与实现

介绍了移动教务信息查询系统的原理及解决方案。系统基于Java技术,客户端采用J2ME,服务器端采用J2EE,通过移动网络实现手机等移动终端访问教务信息系统。并以成绩查询为例说明了系统的实现方法。     

基于无线传感器网络的移动数据库体系结构的研究

无线传感器网络数据需要数据库的管理,用户有随时随地查询数据的要求,提出了一种基于无线传感器网络的移动数据库,它为三层体系结构,介绍了无线传感器网络普通节点层、汇聚节点处移动数据库服务器端和移动客户端这三层的功能组成.     

基于移动终端和3G网络的分布式噪声监测系统

针对噪声污染具有时间上的突发性和空间上的不连续性,设计了由移动终端、外接传声器、移动网络、接收终端组成的分布式噪声网络检测系统.移动终端和外接传声器组成数据采集节点,采集节点采集实时的噪声分贝值,利用移动终端的定位技术,定位到采集节点的当前位置,用移动终端的3G移动网络与接收终端连接,将噪声信息和位置信息打包发送到接收终端,接收终端负责接收各个节点的噪声信息和位置信息,利用LBS的Web技术,将数据以二维地图的方式展示,并且作为服务器提供信息查询服务.实验证明,系统稳定、可靠、成本低,为城市噪声测试提供了一种解决方案.     

基于异步数据广播技术的移动数据库缓存策略

移动客户端数据缓存技术是在目前狭窄的通信带宽中减少数据连接次数的一个重要技术。而数据广播技术是则是利用无线通信网络不对称的特点,使移动客户端数据和服务器端数据保持一致性的最为实用的技术。该文提出一种基于异步广播技术的移动数据库缓存策略。     

LBS-p:一个支持在线地图服务的LBS支撑平台

随着第三代通信技术(3G)和基于位置的服务(LBS)的发展,如何满足LBS用户随时随地的需要、以在线模式提供地图服务等GIS服务,成为一个重要的问题。针对LBS对于在线地图服务的需要,提出了一个基于轻量二进制矢量地图数据格式Byte-Map支持在线地图服务的LBS支撑平台LBS-p。LBS-p由运行在移动设备上的LBS-p mobile和服务器端的LBS-pserver组成。LBS-p mobile是一个基于Java ME平台的应用程序,负责在线地图数据的请求、管理及显示,以及LBS的访问与结果展示。LBS-pserver主要包括3部分:负责为在线地图服务准备地图数据的Byte-Map数据预处理机制;负责响应移动终端的在线数据请求,实时为其提供在线地图数据的Byte-Map数据服务模块;及面向LBS的GIS服务模块。LBS-p利用轻量地图数据格式Byte-Map,通过服务器端的在线地图服务模块和移动终端模块实现在线地图服务。     

基于WebGIS/GPRS/GPS的远程监控系统设计

设计了一个基于WebGIS/GPRS/GPS技术的挖掘机远程监控系统,详细阐述了数据采集、远程控制以及地理信息Web查询等功能的实现,并且提出了保证系统稳定性与安全性的有效措施.其服务器端使用.NET技术编写WebGIS程序,移动终端采用GPS/GPRS技术采集和传递数据.     

一个基于移动Agent的LBS系统

LBS系统可对移动终端定位并提供各种与位置相关的业务。但是其信息的迂回查询将导致网络拥塞,严重影响服务质量。而近年来迅速发展的移动Agent可以在异构的网络环境中自由移动,有效地降低分布式计算的网络负载,提高通信效率。文中将移动Agent技术与LBS相结合,实现了查询数据流量的大幅减少和系统效率的提高。     

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