The notion of certain answers arises when one queries incompletely specified databases, e.g., in data integration and exchange scenarios, or databases with missing information. W...
Digital libraries are more and more available on the web. However, retrieving information in these libraries is not easy because of sources heterogeneity and distribution. Thus, w...
Previous studies of incomplete XML documents have identified three main sources of incompleteness – in structural information, data values, and labeling – and addressed data ...
ct One significant effort towards combining the virtues of Web search, viz. being accessible to untrained users and able to cope with vastly heterogeneous data, with those of dat...
Data integration systems provide a uniform query interface (UQI) to multiple, autonomous data sources [4]. This paper presents the universal data model (UDM) that captures the sem...