基于COM组件技术的GIS空间模型库研究

已有的研究表明 ,空间分析功能是 GIS区别于其他系统的本质特征之一 ,然而当前大多数的 GIS都没有空间模型库 ,这在一定程度上制约了 GIS空间分析能力的实现 ,而对于 GIS中相同或相似的空间分析功能 ,在许多应用系统中则又分别进行了重复或二次开发 .这样的重复工作 ,显然是对人力物力资源的浪费 .通过引入软件工程的 COM组件技术 ,在研究空间模型库构建的基础上 ,设计了空间模型组件库的总体框架 ,探讨了空间模型组件的实现技术 .研究表明 ,基于 COM组件技术的空间模型组件库 ,在增强 GIS组件复用性的同时 ,也有助于 GIS的空间分析功能的实现 .     

GML在网格GIS中的应用研究

介绍了当前网络型GIS的空间地理数据的传输方法，并在介绍网格GIS特点的基础上分析了其优缺点。由此引入GML(Geography Markup Language)，分析其在网格GIS应用中所特有的优越性，进而探讨了如何在网格GIS中应用(GML描述空间地理数据，设计网格GIS通信机制，以解决网格GIS中空间地理数据的存储和传输的问题。     

知识推理在GIS中的应用

传统的GIS平台具有完成数据采集、管理、存储、处理和一定的空间分析功能,但其空间分析推理和决策能力较弱。将人工智能中有关推理、分析的技术引入到GIS中,使GIS能够具备一定的空间推理分析能力,将弥补GIS对于决策支持方面的不足,发挥其效能,使之能够解决更为复杂的问题。并在最后设计了一个“自助驾车游北京”的智能咨询模型。     

一种实时Web GIS优化模型的研究

通过引入异步调用机制和缓存技术,提出了一种实时Web GIS优化模型,解决当前Web GIS中用户体验与空间分析能力之间的矛盾.文中详细描述了该优化模型的组成结构和工作原理,对异步调用机制和缓存技术的应用进行了讨论,并给出了性能测试和分析,验证了该实时Web CIS模型的可行性.     

用蚁群算法实现地理信息系统空间曲线的描述

曲线是GIS空间数据的重要空间目标之一,也是描述面和体的基础。当前的GIS产品中,描述GIS空间曲线使用的是数学和插值方法,并使其可视化。用蚁群算法对GIS空间曲线进行描述,使其具有智能的性质。通过理论分析和模拟实验,表明用蚁群算法描述GIS空间曲线乃至其他空间目标,是可行和有效的。     

在VB利用内存映射文件读取大数据量原始遥感影像图

原始遥感影像数据一般是经过粗处理后以二进制格式提供给用户。这些影像数据同一般的图像数据相比数据量较大,通常采用专业遥感软件进行读取和处理。但当前应用中对遥感数据处理和分析的方法大多都要和GIS相结合,而当前国际流行的商业GIS一般都不具有图像处理功能,同样在商业遥感影像处理软件方面也很难发现较强的GIS功能。如何把GIS和RS有效地结合起来,是目前实际应用中面临的一个问题。论文在分析GIS和遥感影像处理功能集成的方法和意义的基础上,对比了传统文件读取方法和内存映射文件处理方法之间的差异,并给出了利用内存映射文件的方式显示和处理大数据量原始影像文件的具体实现思路。     

基于AIS与GIS的船舶监控管理系统研究

通过AIS与GIS技术的集成,可以利用GIS强大的空间数据处理能力和空间分析功能促进AIS技术的应用。本研究将GIS的空间分析功能应用于AIS基站选址分析,对珠江口区域的AIS基站布局进行规划;应用Winsock网络通信接口进行开发,实现了多个AIS基站与一个或多个监控中心的点对点通信;基于组件式GIS进行系统设计与开发,实现了对近海船舶的自动识别和监控管理。     

基于GIS的北航周边商业房地产研究

利用GIS技术对北航周边商业房地产空间分布现状进行了分析，并采用多元线性回归方法研究了商业房地产与周边高校的内在关系，结果表明周围知名高校的存在以及良好的交通条件对北航周边地区商业房地产起有利影响，该区域写字楼租金呈偏态分布，租金水平与物业级别及建筑面积存在明显的相关性。     

GIS与RS系统集成研究

RS信息具有周期动态性、信息丰富、获取效率高等优势,而GIS则具有高效的空间数据管理和灵活的空间数据综合分析能力,但两者均有一定的局限性。随着GIS技术和RS技术的发展,人们迫切希望能够将RS的强大的图像处理与GIS强大的空间分析等结合起来,解决日益复杂的环境问题,因此,GIS与RS的系统集成问题成为关注的热点。本文通过综合分析GIS与RS系统集成现状,探讨GIS与RS系统集成的技术方法、关键问题和方式。随着对地观测技术的发展,以RS为核心,融入GIS功能的系统集成已成为当前发展的主要趋势。     

“虚拟―现实”一体化的三维 CyberGIS 系统设计

针对当前网络空间与现实空间研究分离之不足,通过IP定位及相关网络属性采集,建立互联网资源及用户空间数据库,分层分区投影到三维数字地球复合坐标系中,实现三维CyberGIS"虚拟―现实"一体化定位、查询和分析功能,有效拓展了地理信息服务(Geographic Information System,GIS)对虚拟空间要素的集成管理能力。     

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.     

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.     

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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