The concept of “approximate” searching has applications in a vast number of fields. Some examples are non-traditional databases (e. g. storing images, fingerprints or audio clips, where the concept of exact search is of no use and we search instead…

The term Federated Databases refers to the data integration of distributed, autonomous and heterogeneous databases. However, a federation can also include information systems, not only databases. At integrating data, several issues must be addressed. Here, we focus on the problem…

Ontologies serve as a mean to establish a conceptually concise basis for communicating knowledge for many purposes. Within the information integration area, ontologies are useful to solve heterogeneity problems. They provide a set of knowledge terms, including the vocabulary, the…

The studies of Relational Data Base Management Systems and Databases constitute nowadays a main tren of investigation in large businesses and universities of the entire world. The creation of a data base engine keeps being a challenge since there are…

Most information in science, engineering and business has been recorded in form of text. This information can be found online in the World-Wide-Web. One of the major tools to support information access are the search engines which usually use information…

Since huge amounts of spatial data can be easily collected from various applications, ranging from remote sensing technology to geographical information system, the extraction and comprehension of spatial knowledge is a more and more important task. Many excellent studies on…

The Web has became an obiquitous resource for distributed computing making it relevant to investigate new ways of providing efficient access to services available at dedicated sites. Efficiency is an ever-increasing demand which can be only satisfied with the development…

blic Keys Schemes usually generate two pairs of keys that bear some mathematical relation-usually, a relation of the field known as Number Theory. Identifying a key from another that is given is a problem of great difficulty. This paper presents…

This document describes a research and development project - Semantic Web and Cooperative Problem Solving for Online Communities of Practice. The aim of the project is to build a system supporting Cooperative Problem Solving within the framework of online Communities…

This paper describes an approach to On Line Analytical Processing (OLAP), expresed in the declarative programming paradigm.
We define a collection of functions that capture some of the functionality currently provided by multidimensional database product. This is done by defining…