A System For Gathering Web Ontologies

Ontologies, which provide a concise, uniform and formalized description of semantics, are gaining incrising significance due to the demands in academia and industry. In our research, an ontology is a document in Semantic Web language which represents the concepts and the relationships holden among them. A breakthrough in ontology technology would require methodological aids and tools that enable effective and efficient development. A key aspect in achieving this is successful reuse of ontologies.To facilitate reuses of ontologies and to support ontology construction, a few of organizations have made researches and developed some application systems. An ontology library system is an important tool in organizing and managing ontologies. It facilitates reuses of ontologies by offering various functions for managing, querying and adapting ontologies. Swoogle is an indexing and retrieval system developed by UMBC for Semantic Web documents. It extracts metadata for each discovered document, and computes relations between documents to provide various retrieval services for ontology-related applications. However, the lack of ontologies has hammered the functions of these systems due to the lack of efficient methods and power tools to acquire ontologies.To address the problems of existing systems we propose to develop a system for gathering Web ontologies based on the technology of Focused Web Crawling.A crawler is a software component for gathering information resources on the Web which runs in the background of a Search Engine or and so on. A Focused Web Crawler crawls the Web selectively and gathers pages according to the established interests and best-first search stratage. And its crawl is more efficient.This paper makes theoretical researches on principles, technologies and methods for gathering Web ontologies based on a Focused Web Crawler. And then we make experimental studies on it. The main contribution of the paper includes the following: Analysing and concluding the distribution of ontologies on the Web; Presenting an integrated method on linkage evaluation for searching ontologies on the Web; Designing and implementing a system for gathering Web ontology documents, called"WebOnto Crawler".