Cecilia Delgado

Primitive Operations for Schema Evolution in ODMG Databases

Schema evolution is the process of applying changes to a schema in a consistent way and propagating these changes to the instances while the database is in operation. In this process there are two problems to consider: semantics of change and change propagation. In this paper, we study the problem of the semantics of change for the schema evolution defined with the ODMG object model. In this context, we provide a formal definition of this object model, we establish a set of axioms to ensure the consistency of a schema when it is modified, and we define a set of primitive operations that allow basic changes to be carried out on an ODMG schema. Other operations, which allow any kind of modification to be carried out, can be derived from these primitives.

Easing the Definition of N---Ary Relations for Supporting Spatio---Temporal Models in OWL

There are many issues to overcome when integrating different data sources due to the number of variables that are involved in the integration phase. However we are interested in the integration of temporal and spatial information due to the nature of modern Information Systems. We have previously developed a model, called STOWL, which is a spatio-temporal extension of OWL. We use this model as the common model for defining the schemes of the data sources in order to ease their integration. This paper presents the part of STOWL which has to do with the definition of n-ary relations.

Fuzzy integration of web data sources for data warehousing

In this paper we show our work related to an approach for monitoring web sources on the World Wide Web using its temporal properties in order to integrate them in a temporal Data Warehouse. We use these temporal properties obtained for integrating data more efficiently from different data sources according to the requirements of the Data Warehouse administrator. For this integration process we proposed a parallel fuzzy temporal semantic algorithm based on a flexible query language called FSQL in order to obtain more precise data in the Data Warehouse. In addition, we show an application applied to tourism area where data integrated into Data Warehouse can be used to schedule personalized travel as a value-added service for electronic commerce.

STOWL: An OWL Extension for Facilitating the Definition of Taxonomies in Spatio-temporal Ontologies

The spatio-temporal information is becoming more popular day by day. Well known web services (google maps, virtual earth...) make this type of information available to the public. On the other hand the Web is tending to the Semantic Web. The OWL language, the ontology description language the Semantic Web is based on, lacks some of the desired features for representing spatio- temporal information. We have developed an OWL extension which tries to encompass this issue. In this work we focus on how the OWL language has been extended in order to consider properties for defining taxonomies.

Fuzzy logic for the performance assessment of the innovation management in tourism

The innovative performance of companies has been studied quite extensively for a long period of time. However, the results of those studies have not yet led to a generally accepted indicator of innovative performance or a methodology to assess Innovation Management. This paper assumed the multidimensionality of the Innovation Management as an outcome of complex interactions. Because of this, it is proposed a design of a methodology to assess Innovation Management based on principles of the Fuzzy Logic. The established methodology stages constitute a guide to develop Innovation Management assessment. In the research development, it was necessary to contextualize, in the conditions of the touristic sector, the theories, models and systems used in the analyzed subject.

System of Indicators in the Innovation Management: Business Intelligence Applied to Tourism

The work presents an approach to study mechanisms that allows managers the Innovation Management (IM) measurements. It is assumed, as main motivation, the analysis of patterns for the design of an integral system of indicators. A methodology that integrates the thought process, focusing on the Business Intelligence and the Balance Scorecard will be presented. A group of indexes based on the multidimensionality of IM in organizations of the sector of tourism is proposed. To approach this quality it is necessary to contextualize, in the conditions of sectoral operation, the theories, models and systems used in our approach. It has been used intervention methods like experts’ criteria, consensus search techniques by means of surveys, consultation of documents, and statistical methods such as analysis of the main components.

Information System Architecture for Data Warehousing

One of the most complex issues of the integration and transformation interface is the case where there are multiple sources for a single data element in the enterprise Data Warehouse (DW). There are many facets due to the number of variables that are needed in the integration phase. However we are interested in the temporal integration problem. This paper presents our DW architecture for temporal integration on the basis of the temporal properties of the data and temporal characteristics of the data sources. The proposal shows the steps for the transformation of the native schemes of the data sources into the DW scheme. In addition we present two new components for temporal integration: Temporal Integration Processor and Refreshment Metadata Generator, which will be used for integrating temporal properties of data and generating the necessary data for the later refreshment of the DW.

OWL extension for integrating spatio-temporal data: dealing with taxonomies

The spatio-temporal information is becoming more popular day by day. There are many data sources which provide highly focused information based on this kind of data. The development of tools which integrate the data provided by those data sources is a complex task. There are few applications which can help in the process. One of the first steps to solve this issue is the development of a common data model which all data sources schemes are translated to. In this paper is proposed a spatio-temporal extension of OWL as this common data model. The work is focused on how this extension deal with information organised in taxononies.

On Operations to Conform Object-Oriented Schemas

To build a Cooperative Information System from several pre-existing heterogeneous systems, the schemas of these systems must be integrated. Operations used for this purpose include conforming operations, which change the form of a schema. In this paper, a set of primitive conforming operations for Object-Oriented schemas are presented. These operations are organized in matrixes according to the Object-Oriented dimensions —Generalization/Specialization, Aggregation/Decomposition— on which they operate.