一种基于智能体的Web文档预取模式

文章深入分析了用户对Ｉｎｔｅｒｎｅｔ资源的访问模式和ｗｅｂ文档自身的更新模式,并提出了一个新的基于智能体的ｗｅｂ文档预取系统结构。在这个系统结构基础上,通过用户存取日志及各种算法,发现特定用户感兴趣的主题,实现对兴趣文档的主动预取,从而提高分布式信息系统上信息的获取效率。     

一种Internet自动信息查询模式

一种在Ｉｎｔｅｒｎｅｔ国际互联网上，克服信息流通瓶颈，建立一种基于用户双向反馈功能的检索模式，并举例介绍了借助于Ｒｅｆｅｒｅｎｃｅ．ＣＯＭ的检索引擎，通过Ｉｎｔｅｒｎｅｔ新闻组，灵活进行自动查询信息的搜索引擎主动式信息服务方法。     

Internet信息检索机制与技术

为了准确、快速地检索Ｉｎｔｅｒｎｅｔ上丰富的信息资源,世界各地的专家对Ｉｎｔｅｒｎｅｔ信息检索技术进行了深刻的研究。由于Ｉｎｔｅｒｎｅｔ在中国发展较晚,其信息检索方面的研究也相对薄弱,因此有必要对Ｉｎｔｅｒｎｅｔ信息资源的检索技术予以讨论。１　Ｉｎｔｅｒｎｅｔ文本信息资源检索在Ｉｎｔｅｒｎｅｔ上,为了使用户比较容易的检索到所需要的各种文本信息资源,经常使用的一些文本检索工具有Ａｒｃｈｉｅ、Ｇｏｐｈｅｒ、Ｖｅｒｏｎｉｃａ和ＷＡＩＳ等。１．１　文件名检索服务ＡｒｃｈｉｅＡｒｃｈｉｅ是由加拿大麦吉尔…     

关键词密度分布法在偏重摘要中的应用研究

偏重摘要系统是实现智能化信息服务的基础，偏重摘要不区分单文档与多文档，根据用户需求为用户提供结果。该文实现了用关键词密度分布方法获取偏重摘要的一个实验系统。研究了基于关键词密度分布方法生成摘要句的策略，通过两种不同的实验，对系统进行了评测。对实验结果进行了讨论。实验证明，该系统能够基本满足用户的查询要求，在基于检索任务和基于问答任务的两项不同的评测中均得到了较好的实验结果。     

Internet上各类化学信息与资源的检索

介绍了Ｉｎｔｉｒｎｅｔ的发展,Ｉｎｔｅｒｎｅｔ所提供的各种服务,以及通过Ｉｎｔｅｍｅｔ获取各种化学信息和资源的新趋势,着重介绍了运用通用搜索引擎和各种化学主题检索各类化学信息与资源,并对部分重要的化学信息和资源的网址提供了详细列表。     

基于XML文档检索的存储研究与实现

因特网诞生以来,网络信息资源急剧增长,如何利用数据检索技术有效的发现和使用资源成为急待解决的问题.对如何更好的检索XML等结构文档,已经作了大量的研究,提出了许多有效的查询方法,但目前对结构文档的索引结构及存储的研究却比较少,因此本文探讨了XML文档检索模型存储结构的主要技术问题,并提出了对置入表进行压缩编码的一种基于数据库存储的方案.     

结合邻近度的语义位置语言检索模型

在传统的检索模型中,文档与查询的匹配计算主要考虑词项的统计特征,如词频、逆文档频率和文档长度,近年来的研究表明应用查询词项匹配在文档中的位置信息可以提高查询结果的准确性。如何更好地刻画查询词在文档中的位置信息并建模,是研究提高检索效果的问题之一。该文在结合语义的位置语言模型(SPLM)的基础上进一步考虑了词的邻近信息,并给出了用狄利克雷先验分布来计算邻近度的平滑策略,提出了结合邻近度的位置语言检索模型。在标准数据上的实验结果表明,提出的检索模型在性能上要优于结合语义的位置语言模型。     

应用Web技术建立电力系统信息资源中心

本文根据当前Ｉｎｔｅｒｎｅｔ由初期的信息发布中心向未来的服务中心角色转变的趋势,利用最新的三层Ｃｌｉｅｎｔ／Ｓｅｒｖｅｒ结构、Ｗｅｂ数据库开发技术和交互式动态页面开发技术,论述了已开发成功的基于 Ｗｅｂ的电力系统信息资源中心站点的开发经验。其中重点提出了基于 Ｗｅｂ的计算代理服务的概念,提出利用ＣＧＩ的技术将现有的命令行计算程序无须改变的集成为电力系统计算代理库控件,充分利用其计算能力的方法,并给出了用此方法构造的基于Ｗｅｂ的潮流计算代理的实现和结果。同时文中还介绍了利用 Ｗｅｂ数据库技术实现可提供查询等服务的电力系统参考文档中心、网上资源链接中心、标准资源和应用软件中心、电力系统网上计算代理中心、电气设备参数查询系统和适用于实际部门的电力系统运行方式和参数在线检索中心等。     

电子文档信息自动挖掘技术中的预处理研究

基于Internet的信息挖掘是数据挖掘技术中的重要组成部分,也是网络信息处理领域中的一项新课题。本文介绍了Internet上的电子文档信息自动挖掘的概念和系统的体系结构,并给出了文档结构图解析、文档分类检索等电子文档自动挖掘的预处理过程及处理程序。     

基于改进VSM的大规模真实文档自动分类系统的研究和实现

随着Ｉｎｔｅｒｎｅｔ和光盘等大容量存储技术的迅速发展，如何迅速、有效地从大量信息中找到所需的信息已成为一个迫切需要解决的问题。文档自动分类系统就是将文档自动归到一个或几个文档类别中去，这一技术的发展将在信息检索、邮件分类、电子会议、信息过滤等许多环境中得到广泛应用。本次首次对传统的文档内容表示方法ＶＳＭ（向量空间模型）作出改进，并针对系统特点提出了具体的分类算法。目前，本系统已初步实施完成并应用于江苏省“九五”重点攻关课题──“Ｉｎｔｅｒｎｅｔ数字图书馆”之中，取得了良好的效果。     

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