The Semantic Index System - SIS

Contact Person: Dr. Martin Doerr  

Complete Description (pdf file) 
Complete Documentation (including users' manuals & programmers' manuals)

The Semantic Index System (SIS) is a tool for describing and documenting large evolving varieties of highly interrelated data, concepts and complex relationships, as opposed to large homogeneous populations in fixed formats (handled by traditional DBMS). As such, it is suited for the representation of scientific knowledge, engineering constructs and metadata. These kinds of data are also characterised by relative stability, i.e. they undergo few updates by comparison to, say, administrative, financial or observational data, which give rise to continuously changing sets of uniform items. SIS has been developed by the scientific team of ISL, under the supervision of Martin Doerr & Panos Constantopoulos.

General Characteristics

The SIS consists of a persistent storage mechanism based on an object-oriented semantic network data model, and a generic interactive user interface to insert and retrieve information in various ways. Several automatic interfaces to other systems and customised user interfaces are provided. The SIS offers significantly richer referencing mechanisms than relational or ordinary object oriented systems, allowing for compact representations of complex data.Together with its metamodelling capability and run-time extensible schema, the system fosters successive integration of different application on the same body of data, ensuring a long life-cycle in changing environments. The high query speed along references allows to use run-time deductions instead of maintaining redundant data. Structural knowledge, as in the SIS, is easily understood by non-experts. Moreover, its implementation is straight-forward and highly efficient, suitable for very large amounts of data. The SIS outperforms relational systems on the market in lookup and traversal access times by an order of magnitude. Thus, it currently is a unique pragmatic solution for efficiently handling very large sets of highly structured data.

Main features

The main features of the SIS, listed below, result in a powerful combination of presentational flexibility, access efficiency and ease of adaptation:

  • Uniform treatment of data and schema
  • Powerful knowledge representation
  • Customisable generic user interface
  • Multimedia data
  • Standard features
  • Database co-operation


Applications using SIS