enhanced Knowledge Warehouse

One can observe a constantly-growing importance of external information in the decision making process. Business users are faced with the problem of an increasing amount of information. What they need is up-to-date, relevant, and well-organized information, but what they have available is distributed and unstructured information stored in heterogeneous sources. Our idea is to organize unstructured data in the data warehouse. As the management guru Peter Drucker argues, the challenge is "to organize outside data because change occurs from the outside." However, we should not limit ourselves to using external sources alone. Data warehouse users should be presented with organized external information that logically extends internal structured information.

Nowadays, the Web is a collection of information, and thus far there is no means to process this information. The Semantic Web (SW) offers a new foundation for organizing knowledge. It intends to provide access to heterogeneous and distributed information, thus enabling software applications to mediate between user needs and the information sources available. Another important topic today is making applications accessible through the Web as web services. One can combine web services together with the Semantic Web in order to achieve synergy. The ultimate vision of the Web is that of a distributed computational device. In order to make the device work, we need special web services capable of information processing. eKW could be one of such services employed to process knowledge, hence the word "knowledge" in the name. enhanced Knowledge Warehouse was modeled to conform to a new way of building applications, namely, the web services. According to the requirements of the modeling framework, it was decomposed into the following independent services:

  • Library Service, for storing documents and making them available to users
  • Profiling Service, for defining organization's long-term information needs extracted from information systems
  • Filtering Service, for selecting documents that match the long-term information needs
  • Indexing Service, for preparing semantic, temporal, and spatial indexes of documents
  • Reporting Service, for retrieving documents relevant to the temporary user needs.

The main role of eKW in the Semantic Web is mediation. The concept of mediation was developed in heterogeneous and distributed information systems. eKW is a kind of data mediator that employs ontologies as a conceptualization layer. It allows mediation between internal management information systems and the Web. Ontologies, and business ontologies in particular, are with no doubt, the most important structures developed within eKW. The necessary mediation between different information systems could be then carried out based on the ontologies. The use of ontologies would also allow better representation of user information needs. The main contribution of eKW will be the means to match documents with user information needs in terms of different contexts; i.e. corporate knowledge, semantic, temporal, spatial, and personal.