Research On The Applications Of Metadata Technology In Digital Libraries

With the development of Internet and the extension of bandwidth, the research and practice on digital libraries has been a hotspot in the process of library informalization,which goal is to provide services for efficient use of Internet information resources. At present, there exists three problems in the use of information:the first is the efficiency in retrieving,the second is the problem of interoperability,and the third is the distribution of large amount of data. The main reason of low efficiency in information retrieval is that the organization of information has not a criterion and that the heterogeneity and distribution of information resources, from which derives the two tasks for digital library:to organize digital information efficiently and to solve the problem of interoperability for distributed,heterogeneous information resources.This paper first gives a brief introduction of the conception and status quo of digital library and metadata and the relationship between them. The aim of applications,the description method and interoperability problems of metadata are also stated. Then a metadata architecture based on information bus is presented. The idea of information bus is from CORBA technology. After analyzing the services provided by information bus,the demand on metadata is proposed. Then four metadata facilities in the architecture are elicited and their functionality and relationships are explained.As the core of information bus, library service proxy is a bridge between users and information resources. So we introduce digital library interoperability protocol (DLIOP) in detail, which is a kind of communication mechanism between users and library service proxy. We discuss some of the problems during the communication process and give an implementation scenario of search interaction.Last,we discuss several problems in the construction of HoHai University digital library. Then based on CORBA technology,we build a metadata architecture of HoHai University digital library and construct a Description-based Library- Service Proxy Model. Metadata description of content and service information in the digital library are also presented,and this provides an efficient solutions for the integration of heterogeneous digital libraries.