Current Web is not enough to fulfill the needs of present and future users. Certain limitations like inefficient searching, lake of automation in accessing, fetching, processing and integrating data over Web. Semantic Web is a hope to overcome from the short comes. In this approach information are in a form which is easily machine understandable and has semantics in the form of metadata. More intelligent search engines/agents automate the process of searching, fetching and accessing the relevant information from various source, can be possible without human assistance. OWL is a standardize language for developing Ontology which are knowledge base for semantic web. To engineer Ontology using OWL a domain expert has to start from scratch, using Protégé a standard tool for Ontology engineering based on OWL. For the reusability of the knowledge which is already there in software world for almost all domain, UML based approach is used. Rational Rose is a UML based tool. Digital Library Management System (DLMS) is used as the domain for Ontology engineering. Comparison shows Rational Rose is better in reusability and editing of knowledge but lakes in expressiveness and query support from Protégé.
Keywords: Ontology, Ontology engineering, UML, RDF, Digital library management system, Ontology mapping.