The scan of a genomic database aims to detect similarities between dna or protein sequences. This is a time-consuming operation, especially when weak similarities are searched. Speeding up the scan can be managed using various strategies of paralleliza-tion. This paper presents two approaches carried on at irisa: systolic and distributed parallelization.

Conclusions 65 Bibliography 67 5 Introduction In information systems, data privacy refers to the confidentiality of certain information that might be stored in the system. systems are often required to share part of their data with third-parties. This can be realized, for instance, through direct access to the systems or through reports that are provided at a future time. Privacy concerns arise...

This paper investigates a consistent version cwaS Reiter’s closed world assumption cwa. It proves (cf. theorem 4.11) that for purely relational languages cwaS is ∀-complete with respect to minimal semantics, i.e. for every ∀-sentence φ and for every ∀-theory Σ, φ ∈ cwaS(Σ) iff Σ `min φ. Moreover, it relates cwaS to other known syntactic characterization of minimal semantics: Minker’s GCWA.

Users of computerized dictionaries require powerful and flexible tools for analyzing and manipulating the information in them. This paper discusses a system for grammatically describing and parsing entries from machine-readable dictionary tapes and a lexicai data base representation for storing the dictionary information. It also describes a language for querying, formatting, and maintaining di...

Summarizability of OLAP and Statistical Databases is an a extremely important property because violating this condition can lead to erroneous conclusions and decisions. In this paper we explore the conditions for summarizability. We introduce a framework for specifying precisely the context in which statistical objects are defined. We use a three step process to define normalized statistical ob...

T w o reasons for such systems are seen (I) As A . I . programs develop from toy domains using toy data bases, to more realistic exercies. the management of the knowledge base becomes nont r i v i a l and requires program support (2) A powerful way to organize LISP programs is to make them data-driven, whereby pieces of program are distributed throughout a data base A data base management syste...

In this paper, we define the SMARTBASEG architecture and show the preliminary results we have obtained in some experiments. Our proposal considers that the domain of Data Mining (DM) can be represented in terms of an ontology containing the definition of the main concepts involved in its algorithms. We also use ontology to describe some characteristics of a computational grid. This declarative ...

The idea of a seamless, scaleless data base of digital spatial data for use in auto mated cartography or geographic information systems has intrigued researchers for a number of years. Yet reviewing the plans of mapping agencies in the United States and Europe for their digital data bases in the 1990's shows partitioning by scale, space, and time. Why is this so? Is a seamless, scaleless data b...

In this paper we examine the connection between two areas of semantics, namely the semantics of historical databases and the semantics of natural language querying, and link them together via a common view of the semantics of time. Since the target application domain is an historical database, we present the essential features of the Historical Relational Database Model (HRDM), an extension to ...