Data warehousing is a software infrastructure which supports OLAP applications by providing a collection of tools which allow data extraction and cleaning, data integration and ag...
View materialization is a central issue in logical design of data warehouses since it is one of the most powerful techniques to improve the response to the workload. Most approach...
The Information Society relies more and more on the co-operation and collaboration of multidisciplinary people who need to communicate and share information. Communication and kno...
The problem of representing and reasoning about two notions of time that are relevant in the context of knowledge bases is addressed. These are called historical time and belief t...
We consider a hierarchy of modal event calculi to represent and reason about partially ordered events. These calculi are based on the model of time and change of Kowalski and Sergo...