In this paper we propose an approach to manage in a correct way valid time semantics for semistructured temporal clinical information. In particular, we use a graph-based data model to represent radiological clinical data, focusing on the patient model of the well known DICOM standard, and define the set of (graphical) constraints needed to guarantee that the history of the given application do...

As with relational data, XML data changes over time with the creation, modification, and deletion of XML documents. Expressing queries on timevarying (relational or XML) data is more difficult than writing queries on nontemporal data. In this paper, we present a temporal XML query language, XQuery, in which we add valid time support to XQuery by minimally extending the syntax and semantics of X...

The methodological integration of the temporal dimension in databases requires primitives that allow rigorous and progressive specification of this dimension since the conceptual and organizational levels. For this goal, we propose concepts and graphic formalisms, in accordance with the abstractions of the tow levels of the entity-relationship model. These concepts allow the expression of requi...