Achieving Semantic Interoperability through Controlled Annotations Michael Gertz Department of Computer Science University of California, Davis

Interoperability —The Facts zThere is a high degree of physical connectivity on the Web, i.e., in terms of exchanging bits and bytes among heterogeneous information sources. zThere is a lack of logical connectivity, i.e., the meaningful exchange, integration, and querying of data. zMetadata are supposed to help adding more semantics to data, but are not frequently used. zWhat are appropriate metadata schemes that help users and creators of Digital Libraries to create and utilize metadata?

The Idea zBuild domain specific ontologies (richer than standard vocabularies); ontologies contain concepts, terms, definitions, and semantic relationships among concepts. zAllow users to associate concepts from ontology with data found on Web pages and sites, at different levels of granularity. zSuch associations are called annotations, providing meaningful and well-defined metadata. zRelationships modeled in ontology are inherited to annotated Web data (  semantic browsing)

An Example zCollection of Monkey Brain Images Cell type B Data as on the Web terms properties relationships spatial temporal semantic Ontology

The Architecture Java Client Browser Annotation server Annotation server Ontology repository Repository Web HTTP

The Major Questions zAre users and creators of Digital Libraries willing to develop ontologies and use them to annotate data? zHow difficult is it to develop cross-language ontologies? zWhat are necessary and useful components of a respective infrastructure? Does XML provide a basis? zWhat types of annotations do users want to make? zWhat are behavior models users employ to make and use annotations? zDo annotations lead to the so-called semantic Web?