Semantic Web: A road to the knowledge infrastructure on the internet

In this article, I describe the basic technologies for Semantic Web and relationship between Semantic Web and Knowledge Representation in Artificial Intelligence. Semantic Web is planned as an extension of the current web in order to help cooperation between computers and humans, i.e., computers and humans are expected to understand each other in the knowledge level. I first describe the vision of the Semantic Web, then introduce the current Semantic Web technologies, i.e., RDF, RDFS, and OWL. I describe relationship between the trend of Semantic Web and Knowledge Representation, and clarify challenges and difficulties of Semantic Web from the point of view of Knowledge Representation. Hideaki Takeda: He is a professor at National Institute of Informatics (NII) and a professor in Department of Informatics at the Graduate University of Advanced Studies (Sokendai). He received his Ph.D. from the University of Tokyo in 1991. His research interest in computer science includes ontology engineering, community informatics and knowledge sharing systems.     

Emerging specializations,competences and firms' proximity in digital industries: The case of London

In order to overcome the limitations of defining industrial specializations in digital industries through SIC codes, this paper suggests measuring the specializations and competences of these industries on the basis of the degree of digital technologies present in the products and services supplied. Metadata from CrunchBase are employed, as proxies of firms' specializations and competences which are defined as the fields of activity in which firms are involved. Applying a network analysis, these specializations and competences are linked to the recognition of emerging digital technologies and the strongest combinations of products and services. We tested the proposed methodology on London, a leading centre for the digital economy.     

数字图书馆科技文献知识导航

提出了一种基于分类法和主题词表的科技文献知识导航体系,该体系支持分类法和主题词表知识导航、元数据结构查询和全文检索这三种检索手段以及他们的混合应用。从分类法主题词表的概念浏览和元数据查询的语义支持的角度来说,这是一个支持概念检索的知识导航体系。根据该体系,实现了“北京大学科技文献检索系统”实验数字图书馆。     

基于数据铸造新技术的肺癌生存率分析系统的设计与应用

生物信息学作为21世纪最有影响力的一个领域,已经取得了前所未有的进步。数据库是其成功发展的一个关键因素。然而,如何将多个数据源集成为一个单一,一致的数据仓库,并在其上建构多种解决某领域专业知识的强大数据挖掘方法,依然是个难题。文章采用一种基于数据铸造机制的数据仓库新技术,提出专门用于预测肺癌生存期的决策算法,进行肺癌生存率的分析,从而有效地采用新型数据挖掘系统解决肺癌生存率预测。     

基于元数据COTS构件的信息系统开发方法

文章在分析了元数据COTS构件特点的基础上，讨论了一种新的信息系统开发方法，并通过一个例子阐明了该方法的优越性。     

空间元数据系统的研究与设计

本文介绍了空间元数据的基本概念，分析了空间元数据标准和空间元数据系统研究的现状和面临的困难，提出了一种有效的空间元数据系统模型，用于采集、管理、维护和发布空间元数据，并实现空间元数据的快速查询和准确定位。     

ECHO: a digital library for historical film archives

Easy access to large information collections is of great importance in many aspects of everyday life. However, limitations in information and communication technologies have so far prevented the average person from taking much advantage of existing resources. Historical documentaries held by national archives constitute some of the most precious yet least accessible cultural information. The ECHO project has facilitated accessibility to this type of precious information by developing a digital library (DL) service for historical films belonging to large national audiovisual archives.     

基于XML的CORBA反射机制的研究

研究一种反射方法，该方法可使CORBA对象以XML格式向客户应用返回元数据，CORBA系统不再需要配置接口池，客户就能动态获取CORBA对象元数据。     

基于元数据的分布异构数据集成研究

将“虚拟法”和“数据仓库法”结合,通过统一的数据交换中心解决数字气田分布异构数据集成问题。建立包含全局模式和全局-局部映射的元数据字典,屏蔽异构数据细节,由此解决异构数据的各种冲突。提出一种由分布数据源的局部模式归并建立全局模式和映射表的算法,以提高模式集成的自动能力。     

海量存储系统中高可扩展性元数据服务器集群设计

海量存储系统都采用元数据服务器机群的方式来处理文件系统的元数据信息。很多存储系统采用Hash算法来实现文件元数据在元数据机群内的分布，但是这些算法都是针对文件进行Hash。本文提出了一种目录哈希的新算法，针对目录进行Hash，并把一个目录内的元数据集中存储。本算法克服了文件Hash的不足，改善了存储系统的性能，并极大地提高了存储系统的可扩展性。