On Designing the SONCA System

The SYNAT project aims to develop a universal, open hosting and communication platform for network knowledge resources for science, education and open information society. The stage B13 of this project aims to develop methods and algorithms of semantic indexing, classification and retrieval using dictionaries, thesauri and ontologies as well as methods of processing and visualizing results. The methods and algorithms aim to support the dialogue with the repositories of text and multimedia resources gathered on some servers. To realize the objectives of the stages B13 and B14 of the SYNAT project we plan to develop and implement a system called SONCA (Search based on ONtologies and Compound Analytics).

We present ideas and proposals for the SONCA system. The main idea is to allow combination of metadata-based search, syntactic keyword-based search and semantic search, and to use ranks of objects. Semantic search criteria may be keywords, concepts, or objects (for checking similarity). Search criteria based on metadata play the role of exact restrictions, while syntactic keywords and semantic search criteria are fuzzy restrictions. To enable metadata-based search, an appropriate document representation is used. To enable syntactic keyword-based search, each document (object) is stored together with information about the terms occurring in its text attributes. The terms are normalized and only important ones are stored. To enable semantic search, the representation of each document (object) is extended further with the most important concepts that characterize the document. Such concepts belong to the main ontology of SONCA.

We provide an abstract model for the SONCA system, an instantiation of that model, some ideas for the user interface of SONCA as well as proposals for increasing efficiency of the query answering process.