基于Open Source的全文检索框架

本文在开源(Open Source)项目Jakarta Lucene的基础上,结合多种开源文档格式分析工具,设计和实现了一种可扩展的全文检索框架,该框架可高效地对XML、HTML、MS Word、PDF等格式的文档进行全文检索.整个框架完全基于开源工具包,可以有效地对信息系统的开发进行支持.     

Websphere：活吞市场的大鲸

1999年，IBM与Novell签订合作协议，成功地提供电子商务的解决方案给予原先使用NetWare的用户。同年更是推出了WebSphere Application Server3．0，并且推出WebSphere Studio与VisualAge for Java让工程师可以快速开发相关的程序。2001年，IBM更是宣布将应用服务器、开发工具整合在一起，与DB2、Tivoli及Lotus结合成为一套共通解决方案，如今、IBM更是并入了Rational Rose(UML tools)让开发流程更是完整化。     

基于XML的开放式WebGIS的系统设计

基于XML的开放式WebGIS的系统设计是解决传统WebGIS数据共享、服务互操作问题的好方法.本文分析了基于XML的开放式WebGIS系统的设计目标,提出了一个基于XML技术的WebGIS系统设计方案.     

计算机网络信息安全面临的问题和对策

计算机的广泛应用把人类带入了一个全新的时代,特别是计算机网络的社会化,已经成为了信息时代的主要推动力.目前,全世界的军事、经济、社会、文化各个方面都越来越依赖于计算机网络,人类社会对计算机的依赖程度达到了空前的纪录.由于计算机网络的脆弱性,这种高度的依赖性使国家的经济和国防安全变得十分脆弱,一旦计算机网络受到攻击而不能正常工作,甚至瘫痪,整个社会就会陷入危机.     

思科与北大共建领导力研究院并宣布下一阶段在华蓝图网聚领导力共绘新蓝图

4月16日,北大百年讲堂里,数十家媒体再次见到了思科董事会主席兼首席执行官约翰·钱伯斯先生.这是继他自去年11月访华后又一次来到中国.去年11月,钱伯斯来到中国宣布在中国发展的重点是"创新及可持续发展",并且承诺对华投入160亿美元;而这一次他再次来到中国,则是要宣布将这一承诺兑现:思科将在未来三到五年内投入2000万美元与北京大学光华管理学院共同打造领导力研究院.     

历时一年,成效显著--第一届全国数控技能大赛圆满结束

为了深入贯彻全国人才工作会议精神,加强高技能人才的队伍建设,劳动和社会保障部、教育部、科技部、国防科工委、中华全国总工会、中国机械工业联合会共同举办了第一届全国数控技能大赛,经过各部门、各地区以及各承办、协办单位共同努力,全国30个省、自治区、直辖市举办了选拔赛活动,从来自企业和职业院校的近20万名选手中选拔出的422名选手入围全国决赛,其中270多名选手脱颖而出,取得了优异成绩.     

马来西亚2004年《通讯与多媒体法》介评

马来西亚国会于1998年颁布了《通讯与多媒体法》。该法被誉为马来西亚在信息技术立法工作方面最全面的一部,它对部长、上诉院、通讯与多媒体委员会这三个机构的权限、职能作了清楚划分,从经济、技术、社会三方面对网     

汶川地震:感受信息公开的力量

5月12日,一场突如其来的大地震袭击了四川省及其周边一些地区,这场大地震,夺去了数万人的生命,也牵动了国家和亿万人民群众的心。灾害发生后,全体中国人民众志成城,在罕见的特大地震面前表现出钢铁般的意志和战胜灾害的决心。党和国家领导人对抗震救灾工作迅速作出重要指示,温家宝总理灾后四个小时,不顾随时可能发生的余震,亲临救     

高效、高质量的纸质工程图和资料存档方案

一、传统保存方案的缺陷 传统的工程图样和资料的保存归档形式是通过纸质或胶片的形式进行的,很多企业都用专门的仓库保管这些珍贵的技术资料.这些资料的内容相当广泛,包括机械设计、建筑设计、工程设计、测绘及地图等各行业的信息.资料的介质也有不同的分类,包括硫酸纸、纸质蓝图、白图及胶片等.     

婚姻与电脑

茶余饭后的人们总是需要谈资的,而需求的力量往往巨大.所以对于"报纸"的发明和"狗仔队"的产生也就很好解释了,说来每年都有些网络大热话题作为热门话题,不过一般都逃不出什么品牌电脑的促销风暴,还有就是什么名流、富豪榜和个人年终奖的猜想.而在2008年,一场发生在著名主持人张斌和胡紫薇间"婚姻事件"     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

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.     

基于QTE的蒙古文显示机制研究与实现

蒙古语言是中国蒙古族使用的通用语言,由于蒙古文区别于其他文字的书写方式和其自身变形机制等特点,在很多通用的文字处理引擎中都不被支持。在嵌入式产品开发与应用领域中Linux加QTE已经成为流行方式。该文给出了一种在QTE环境上实现基于标准Unicode的蒙古文点阵显示和变形算法, 并自定义了支持蒙古文的QTE组件,扩展了QTE功能,为在Linux加QTE方式的嵌入式体系结构中处理蒙古文提供了一种解决方法。     

基于AD9626的模拟信号采集存储卡设计

自然界的绝大部分信号都是以模拟的形式存在,因此模拟信号的采集转换存储在数字时代十分关键。文章讨论了在雷达信号处理领域基于AD9626的AD采集存储卡的设计原理、硬件结构和程序设计与芯片配置等问题,为今后相关领域的研究提供了可参考的方案。     

A human-computer interface for non-computer specialists

The COM teleconferencing system was designed to be easy to use for both beginners and people with much computer experience. A number of design choices in organizing the human-computer interface were considered very carefully. These design problems are not unique for teleconferencing applications, but will appear in many other developments of human-computer interfaces for non-computer specialists. This report discusses naming conventions, menu format, user commands, help facility and the treatment of ‘type ahead’ from the users.     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

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.     

Call for papers Special issue on Modeling and control technologies for civil,energy,and power systems

正The control of civil,energy,and power systems presents significant new challenges for modeling and control theory.The purpose of this special issue is to provide a forum for researchers and practical engineers to discuss the recent advances in modeling and control technology development for civil,energy,and power systems.Prospective authors are invited to submit their original contributions with the focus on theory or applications of modeling,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 and promote academic exchange between Chinese and foreign scientists everywhere.