Exploiting related digital library corpora with query rewriting (Extended Abstract) ⋆ Federica Mandreoli and Riccardo Martoglia Universit`a di Modena e Reggio Emilia, Dip. di Ingegneria dell’Informazione, Modena, Italy {mandreoli.federica, martoglia.riccardo}@unimo.it Abstract. In this paper, we present the preliminary results of the ongoing re- search activity we are carrying out in the context of approximate XML query answering when the schemas of the XML documents are available. The method we propose involves a preliminary schema matching process, which automat- ically identifies the semantic and structural similarities between the schema elements to be used in the subsequent operation of query rewriting, in which a query written on a source schema is automatically rewritten in order to be compatible with the other useful XML documents. The proposed approach has been implemented in a web service, named XML S 3 MART, which is part of the open architecture proposed in the ongoing Italian CNR co-funded ECD Project. 1 Introduction In recent years, the constant integration and enhancements in computational resources and telecommunications, along with the considerable drop in digitizing costs, have fostered development of systems which are able to electronically store, access and diffuse via the Web a large number of digital documents and multimedia data. In such a sea of electronic information, the user can easily get lost in his struggle to find the information he requires. For these reasons, the concept of Digital Library (DL) has become a pivotal one: Exactly as a physical library, a DL contains a collection of documents that are at the users’ disposal, however it goes much further. In fact, along with the documents themselves, a good DL offers an entire ensemble of systems and services designed to help users to easily find and access the data they are looking for. DLs are now widely available all over the web, but they are still far from perfect in delivering such enhancements to the user. This is the challenging scenario of the ongoing Italian CNR co-funded Project “Tech- nologies and Services for Enhanced Content Delivery” (ECD Project): It is aimed at producing new and advanced technologies in order to enable the development of the next generation of Digital Libraries, offering enhanced contents and services such as thematic catalogues, media collections (audio, video, WAP) and, most importantly, ad- vanced search engines with a cutting-edge search effectiveness. In the next generation DL, data (textual documents or even metadata on multimedia items) are expressed in XML, one of the most open and powerful inter-communication standards available today, and are associated to XML Schemas; queries submitted to the DL search en- gine are written in XQuery [1], a language expressive enough to allow users to perform structural inquiries, going beyond the “flat” bag of words approaches of common plain ⋆ The present work is partially supported by the “Technologies and Services for Enhanced Content Delivery” Fondo Speciale Innovazione 2000 Project.