Uncertain Spatiotemporal Data Modeling Based on XML

Abstract

Information is often imprecise and imperfect. In addition, traditional data models suffer from some inadequacy of necessary semantics such as inability to handle imprecise and uncertain information. In this chapter, the authors establish an uncertain spatiotemporal data model based on XML. Then, on the basis of the model, the authors provide a set of algebraic operations for capturing and handling uncertain spatiotemporal data. By employing algebraic operations, they demonstrate how to translate queries expressed in XQuery to this algebra. A translation example shows that these algebraic operations are full of expressive power and illustrates that this algebra can be applied to general data. Apart from this, the authors also propose a set of equivalence rules to optimize the process of query and give an example to show how the optimization approach works.