155  "   4 -    -3 ’  Giovani Rubert Librelotto UNIFRA ) Centro Universitário Franciscano Rua dos Andradas, 1614 Santa Maria, RS, Brazil, 97010)310 +55 55 9129 4080 giovani@unifra.br José Carlos Ramalho University of Minho Department of Informatics Campus de Gualtar Braga, Portugal, 4710)057 +351 253 604460 jcr@di.uminho.pt Pedro Rangel Henriques University of Minho Department of Informatics Campus de Gualtar Braga, Portugal, 4710)057 +351 253 604460 prh@di.uminho.pt + The ability to extract and merge data that from documents (or databases) of different types, in order to acquire knowledge from a vast repository of information, is of unquestionable value. However that desirable integration is not an easy task. Different approaches can be followed to achieve it, ranging from the merge of resources (implying their conversion to a common format) till the fusion of the extracted parts. The idea is to interoperate those resources keeping them independent, without changes or transformations, creating over them an integration layer that gives us a general overview, as the information slices were gathered. This is possible creating a semantic network, or a conceptual map, over the resources, which relates data items among them mapping each one to its different occurrences in the repository; formally speaking, that conceptual map corresponds to the ontology that describes the knowledge we want to acquire. In this paper, we introduce Metamorphosis, a Topic Maps oriented environment to extract data from heterogeneous information repositories and to generate a browser and conceptual navigator for the extracted knowledge. !  7  H.3.1 [ !  +*] Content Analysis and Indexing – abstracting methods, dictionaries, indexing methods, linguistic processing, thesauruses. 0  Algorithms, Management, Documentation, Reliability, Experimentation, Standardization, Languages. 5’% Topic Maps, Ontologies, Information Systems, Interoperability, Semantic Web. 9.+" Daily, a lot of data is produced by every institution or company. To satisfy the storage requirements, these organizations use most of the times relational databases, which are quite efficient to save and to manipulate structured data. Unstructured data (appearing inside documents) is stored in plain or annotated text files. There is a problem when these organizations require an integrated view of their heterogeneous information systems. It is necessary to query/exploit every data source, but the access to each information system is different. In this situation, there is a need for an approach that extracts the information from those resources and fuses it. Usually this is achieved either by extracting data and loading it into a central repository that does the integration before analysis, or by merging the information extracted separately from each resource into a central knowledge base. Topic Maps [12] are a good solution to organize concepts, and the relationships between those concepts, because they follow a standard notation – ISO/IEC 13250 [2] – for interchangeable knowledge representation. We are using successfully, for some years, this technology for classification and integration of documents in the area of digital archiving. However, the process of ontology development based on topic maps is complex, time consuming, and it requires a lot of human and financial resources, because they can have a lot of topics and associations, as well as the number of resources can be very large. To overcome this problem, we developed Metamorphosis. Metamorphosis makes possible the Topic Maps extraction, validation, storage, and browsing. It is composed of three main modules: (1) Oveia extracts data, from heterogeneous information systems, according to an ontology specification, and stores it in a topic map; (2) XTche validates the generated topic map, according to a constraint specification; (3) Ulisses browses the topic map, enabling a conceptual navigation and query over the resources. This paper describes the integration of heterogeneous information systems using the ontology paradigm, in order to generate a homogeneous view of these resources. The remainder of the paper is structured in the following sections: in section (sec.2) will introduce Metamorphosis, and then a description of each module is presented with some detail (Oveia in sec.3, XTche in sec.4 and Ulisses in sec.5). Before concluding remarks (sec.7) we compare our proposal with related work (sec.6). Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. To copy otherwise, or republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. SIGDOC'08, September 22–24, 2008, Lisbon, Portugal. Copyright 2008 ACM 978/1/60558/083/8/08/0009...$5.00.