Schema Management for Data Integration: A Short Survey

Schema management is a basic problem in many database application domains such as data integration systems. Users need to access and manipulate data from several databases. In this context, in order to integrate data from distributed heterogeneous database sources, data integration systems demand the resolution of several issues that arise in managing schemas. In this paper, we present a brief survey of the problem of schema matching which is used for solving problems of schema integration processing. Moreover, we propose a technique for integrating and querying distributed heterogeneous XML schemas.

A contextual semantic mediator for a distributed cooperative maintenance platform.

International audiencePlatforms expand maintenance systems from centralized systems into e-maintenance platforms integrating various cooperative distributed systems and maintenance applications. This phenomenon allowed an evolution in services offered to maintenance actors by integrating more intelligent applications, providing decision support and facilitating the access to needed data. To manage this evolution, e-maintenance platforms must respond to a great challenge which is ensuring an interoperable communication between its integrated systems. By combining different techniques used in previous works, we propose in this work a semantic mediator system ensuring a high level of interoperability between systems in the maintenance platform

Semantic Modelling of e-Solutions Using a View Formalism with Conceptual and Logical Extensions

In industrial informatics, there exists a requirement to model and design views at a higher level of abstraction. Since the classical view definitions are only available at the query or instance level, modelling and maintaining such views for complex enterprise information systems (EIS) is a challenging task. Further, the introduction of semi-structured data (namely XML) and its rapid adaptation by the commercial and industrial systems increased the complexity for view design and specification. To address such and issue, in this paper we present; (a) a layered view model for XML, (b) a design methodology for such views and (c) some real-world industrial applications of the view model. The XML view formalism is defined at the conceptual level and the design methodology is based on the XML semantic (XSemantic) nets, a high-level object-oriented (OO) modelling language for XML domains

Web and Semantic Web Query Languages

A number of techniques have been developed to facilitate powerful data retrieval on the Web and Semantic Web. Three categories of Web query languages can be distinguished, according to the format of the data they can retrieve: XML, RDF and Topic Maps. This article introduces the spectrum of languages falling into these categories and summarises their salient aspects. The languages are introduced using common sample data and query types. Key aspects of the query languages considered are stressed in a conclusion

Optimized Seamless Integration of Biomolecular Data

Today, scientific data is inevitably digitized, stored in a wide variety of heterogeneous formats, and is accessible over the Internet. Scientists need to access an integrated view of multiple remote or local heterogeneous data sources. They then integrate the results of complex queries and apply further analysis and visualization to support the task of scientific discovery. Building such a digital library for scientific discovery requires accessing and manipulating data extracted from flat files or databases, documents retrieved from the Web, as well as data that is locally materialized in warehouses or is generated by software. We consider several tasks to provide optimized and seamless integration of biomolecular data. Challenges to be addressed include capturing and representing source capabilities; developing a methodology to acquire and represent semantic knowledge and metadata about source contents, overlap in source contents, and access costs; and decision support to select sources and capabilities using cost based and semantic knowledge, and generating low cost query evaluation plans. (Also referenced as UMIACS-TR-2001-51

Configuração e interrogação com sistemas federados

Apesar da existência de produtos comerciais e da investigação na área, a construção de sistemas de informação com diversos componentes distribuídos, heterogéneos e autónomos - conhecidos como sistemas de informação federados - é ainda um desafio. Estes sistemas de informação oferecem uma visão global unificada sobre os vários modelos de dados (parciais). No entanto, a modelação destes sistemas é um desafio, já que modelos de dados como o relacional não incluem informação sobre a distribuição e tratamento de heterogeneidade. É também necessário interagir com estes sistemas de informação, através de interrogações sobre os diversos componentes dos sistemas, sem ser necessário conhecer os detalhes dos mesmos. Este trabalho propõe uma abordagem a estes desafios, através da utilização de modelos para descrição semântica, e.g. linguagem OWL (Ontology Web Language), para construir uma descrição unificada dos seus diversos modelos parciais. O modelo criado para dar suporte a esta descrição é, em parte, baseado em ontologias existentes, que foram alteradas e extendidas para resolver diversos desafios de modelação. Sobre este modelo, é criado um componente de software que permite a execução de interrogações SQL (Structured Query Language) sobre o sistema federado, resolvendo os problemas de distribuição e heterogeneidade existentes

PATAXÓ: A Framework to Allow Updates Through XML Views

XML has become an important medium for data exchange, and is frequently used as an interface to (i.e., a view of) a relational database. Although a lot of work has been done on querying relational databases through XML views, the problem of updating relational databases through XML views has not received much attention. In this work, we map XML views expressed using a subset of XQuery to a corresponding set of relational views. Thus, we transform the problem of updating relational databases through XML views into a classical problem of updating relational databases through relational views. We then show how updates on the XML view are mapped to updates on the corresponding relational views. Existing work on updating relational views can then be leveraged to determine whether or not the relational views are updatable with respect to the relational updates, and if so, to translate the updates to the underlying relational database

Survey over Existing Query and Transformation Languages

A widely acknowledged obstacle for realizing the vision of the Semantic Web is the inability of many current Semantic Web approaches to cope with data available in such diverging representation formalisms as XML, RDF, or Topic Maps. A common query language is the first step to allow transparent access to data in any of these formats. To further the understanding of the requirements and approaches proposed for query languages in the conventional as well as the Semantic Web, this report surveys a large number of query languages for accessing XML, RDF, or Topic Maps. This is the first systematic survey to consider query languages from all these areas. From the detailed survey of these query languages, a common classification scheme is derived that is useful for understanding and differentiating languages within and among all three areas

Uniform resource visualization

Computing environments continue to increase in scale, heterogeneity, and hierarchy, with resource usage varying dynamically during program execution. Computational and data grids and distributed collaboration environments are examples. To understand performance and gain insights into developing applications that efficiently use system resources, performance visualization has proven useful. Performance visualization tools, however, often are specific to a particular resource at a certain level of the system, possibly with fixed views. Thus, they limit a user\u27s ability to observe a performance problem associated with multiple resources across system levels and platforms. To address this limitation, information integration is necessary. In this research, we propose a new performance visualization framework, Uniform Resource Visualization (URV), focusing on integration of performance information into system-level visualizations. The goal of URV research is to systemize the performance visualization of resources with reusable and composable visualizations