Research in temporal databases has largely focused on extensions of existing data models for the proper handling of temporal information. One approach is to store temporal data on existing DBMS and build some new indexes to provide support for the efficient retrieval of temporal data. This paper describes mapping strategies to linearize the data such that existing B +-trees can be used directly...

The proportional-bandwidth and constant-bandwidth timefrequency signal decompositions of the wavelet, Gabor, and Wilson Manuscript received August 21, 1992; revised May 26, 1993. The Guest Editor coordinating the review of this paper and approving it for publication was Dr. Patrick Flandrin. This work was supported in part by the Sound Group of the computer-based Education Research Laboratory, ...

Existing systems for XML views only support selection operation applied in the views and cannot validate views. In this paper, we propose a systematic approach to design valid XML views. First, we transform the semistructured XML source documents into a semantically rich Object-RelationshipAttribute model designed for SemiStructured data (ORA-SS). Second, we enrich the ORA-SS diagram with seman...

Predicting the response at an unobserved location is a fundamental problem in spatial statistics. Given difficulty modeling dependence, especially nonstationary cases, model-based prediction intervals are risk of misspecification bias that can negatively affect their validity. Here we present new approach for model-free nonparametric based on conformal machinery. Our key observation data be tre...

I n valid-time indeterminacy, it is known that an event stored in a temporal database did in fact occur, but it is not known ezactly when the event occurred. W e present an eztension of the tuple-timestamped temporal data model, called the the possible chronons data model, t o support valid-time indetrrtninncy In the possible chronons data model, each event is represented with a set of possible...

Many WWW applications generate HTML or XML documents dynamically. Current tools, however, like languages using DOM or JAVA Server Pages do not allow to check the validity of the generated documents statically. Instead, validity has to be “checked” dynamically by appropriate test runs. This paper addresses this problem by introducing a new distinct class for each element type of a DTD. Each clas...