METALICA: An Enhanced Meta Search Engine for Literature Catalogs

Today there is an increasing if not confusing number of services available for searching and acquiring literature. This makes it more and more difficult for a user to take advantage of these new services. Our goal is to offer user support by providing a meta engine which covers the different services and unifies their access. Additionally, we want to gain a number of synergy effects, enhancing traditional bibliographic information with a combination of complementary content and acquisition information. We also provide the means for a direct comparison of acquisition alternatives. In this paper we present the design and implementation of our METALICA system. By employing a domain model and a global query language, heterogeneous services can be handled in a uniform way. Technical and syntactical homogenization is done by wrappers which consist of a connection control component and a syntax analysis component. Semantic homogenization is accomplished by mediators which contain a query translator and an attribute model translator. An integrator recognizes and unifies duplicates and offers additional operations for grouping and sorting, thereby supporting the user in the exploration of large result collections. The user interface can offer different views of the system s functionality by utilizing a Model-View-Controller architecture.