Ontology-Based Heterogeneous XML Data Integration

2001

XML raises as the standard for semistructured data representation and data exchange in the Web. In this context, data integration mechanisms are required to provide an unified view of semantically related information of a same domain. In this paper, a bottom-up integration process is proposed to solve such problem. In this approach, an ontology is generated from the semantic integration of conceptual schemata derived from DTDs. The process is semi-automatic taking into account the intervention of an human expert to provide semantic adjustments. The resulting ontology is an unified vocabulary for semistructured concepts presented in several XML sources; keeps mapping information to DTD elements and attributes; and acts as a global schema for user queries. The overall integration process is briefly presented through examples.

Lecture Notes in Computer Science, 2002

We define an object-oriented data model called XSDM (XML Schema Data Model) and present a graphical representation of XML Schema integration. The three layers included are, namely, pre-integration, comparison and integration. During pre-integration, the schema present in XML Schema notation is read and is converted into the XSDM notation. During the comparison phase of integration, correspondences as well as conflicts between elements are identified. During the integration phase, conflict resolution, restructuring and merging of the initial schemas take place to obtain the global schema.

TR00-004, University of Florida, …, 2000

2004

Reconciling of knowledge from multiple heterogeneous data sources has been a major focus of database research for more than a decade.As a standard for exchanging business data on the WWW, XML should provide the ability of expressing data and semantics among them. Since most of application data are stored in relational databases due to its popularity and rich development experiences over it.Therefore, how to provide a proper mapping approach from relational model to XML model becomes the major research problem in the field of current information exchanging, sharing and integration..The model needs to be integrated and at the same time maintain the semantic knowledge among the data. The aim of this paper is to provide an overview for XML based data integration on semantic knowledge.At the end of the paper, we review some methodologies from existing literature.

"Semantic Hyper/Multi-media Adaptation: Schemes and Applications", Springer 2013

"In the context of the emergent Web of Data, a large number of organizations, institutes and companies (e.g., DBpedia, Geonames, PubMed ACM, IEEE, NASA, BBC) adopt the Linked Data practices and publish their data utilizing Semantic Web (SW) technologies. On the other hand, the dominant standard for information exchange in the Web today is XML. Many international standards (e.g., Dublin Core, MPEG-7, METS, TEI, IEEE LOM) have been expressed in XML Schema resulting to a large number of XML datasets. The SW and XML worlds and their developed infrastructures are based on different data models, semantics and query languages. Thus, it is crucial to provide interoperability and integration mechanisms to bridge the gap between the SW and XML worlds. In this chapter, we give an overview and a comparison of the technologies and the standards adopted by the XML and SW worlds. In addition, we outline the latest efforts from the W3C groups, including the latest working drafts and recommendations (e.g., OWL 2, SPARQL 1.1, XML Schema 1.1). Moreover, we present a survey of the research approaches which aim to provide interoperability and integration between the XML and SW worlds. Finally, we present the SPARQL2XQuery and XS2OWL Frameworks, which bridge the gap and create an interoperable environment between the two worlds. These Frameworks provide mechanisms for: (a) Query translation (SPARQL to XQuery translation); (b) Mapping specification and generation (Ontology to XML Schema mapping); and (c) Schema transformation (XML Schema to OWL transformation)."

Lecture Notes in Computer Science, 2005

This paper presents a detailed integration process for XML schemata called BInXS. BInXS adopts a global-as-view integration approach that builds a global schema from a set of heterogeneous XML schemata related to a same application domain. This bottom-up approach maps all element and attribute definitions in XML schemata to correspondent concepts at the global schema, allowing access to all data available at the XML sources. The integration process is semiautomatically performed over conceptual representations of the XML schemata, which provides a better understanding of the semantics of the XML data to be unified. A conceptual schema is generated by a set of conversion rules that are applied to a schema definition for XML data. Once this conceptual schema is the result of a meticulous analysis of the XML logical model, it is able to abstract the particularities of semistructured and XML data, like elements with mixed contents and elements with alternative representations. Therefore, the further unification of such conceptual schemata implicitly deals with structural conflicts inherent to semistructured and XML data. In addition, BInXS supports a mapping strategy based on XPath expressions in order to maintain correspondences among global concepts and data at the XML sources. 5 Figure 2 (b) is a logical abstraction of a schema defined through a DTD (Document Type Definition) or an XSD (XML Schema Definition) [5]

Expert Systems With Applications, 2005

Development of an intelligent system requires not only profound understanding of the problem under study, but also employment of different knowledge representation techniques and tools often based on a variety of paradigms and technological platforms. In this context automation of knowledge sharing between different systems becomes increasingly important. One solution might be to extend a knowledge modeling tool by implementing a set of new classes or functions for importing other knowledge formats (using, e.g. Java, CCC, etc.). But, this can be a rather difficult and time consuming task. Since XML is now widely accepted as knowledge representation syntax, we believe that a more suitable solution would be to use eXtensible Stylesheet Language Transformation (XSLT) a W3C standard for transforming XML documents. A special advantage of this approach is that even though an XSLT is written independently of any programming language, it can be executed by a program written in almost any up-to-date programming language. We experiment on an XSLT-based infrastructure for sharing knowledge between three knowledge modeling and acquisition tools that use different conceptual models for knowledge representation in order to evaluate cons and pros of the proposed XSLT approach. Two of these tools, JessGUI and JavaDON are ongoing efforts of the GOOD OLD AI research group to develop interoperable development tools for building intelligent systems, while the third one is Protégé-2000, a broadly accepted ontology development tool. q (J. Jovanović), dgasevic@ acm.org (D. Gašević). 1 Tel.: C1 604 268 7520; fax: C1 604 268 7488.

2008

XML is designed to facilitate data exchange between applications. However, XML and its schema languages do not express semantics but rather the document structure, such as the nesting information. Therefore, in the integration of XML, we should emphasize the semantics more than the document structures. In this paper, we provide a context aware framework, named BICAA, which aims to enhance the XML semantic integration. In BICAA, we generate both DAML+OIL context ontology and context instances. Through this bidirectional approach, we hope to achieve better context-aware computing in the XML semantic integration.

Support in the exchange of data, information, and knowledge is becoming a key issue in current computer technology. Ontologies may play a major role in supporting the information exchange processes, as they provide a shared and common understanding of a domain. However, it is still an important question how ontologies can be applied fruitfully to online resources. Therefore, we will investigate the relation between ontology representation languages and document structure techniques (schemas) on the web. We will do this by giving a detailed comparison of OIL, a proposal for expressing ontologies in the Web, with XML Schema, a proposed standard for describing the structure and semantics of XML based documents. We will argue that these two refer to different levels of abstraction, but that, in several cases, it can be advantageous to base a document schema on an ontology. Lastly, we will show how this can be done by providing an translation procedure from an OIL ontology to a specific XML Schema. This will result in a schema that can be used to capture instances of the ontology. 123

2003

The eXtensible Markup Language (XML) offers many important benefits and improvements over its predecessor, HTML. But, articles have appeared about XML with exaggerated claims of it being a "Rosetta Stone" with "miraculuous ways" to almost automatically provide information integration. These claims are actually being believed by some executives. It is almost surprising that no one has claimed that XML can cure cancer and provide world peace! In reality, XML must face many of the same challenges that plagued Electronic Data Interchange (EDI) and database integration efforts of the past. To a large extent, there are both managerial and technical challenges -much related to the difficulties of attaining universally accepted semantically-rich standards. In this paper, these challenges will be discussed with specific emphasis on the issue of dealing with a real-world with multiple "contexts." Some promising research directions, some overlapping with the "semantic web" effort, will be presented.

Electronic Trans. on …, 2001

Support in the exchange of data, information, and knowledge is becoming a key issue in current computer technology. Ontologies may play a major role in supporting the information exchange processes, as they provide a shared and common understanding of a domain. However, it is still an important question how ontologies can be applied fruitfully to online resources. Therefore, we will investigate the relation between ontology representation languages and document structure techniques (schemas) on the web. We will do this by giving a detailed comparison of OIL, a proposal for expressing ontologies in the Web, with XML Schema, a proposed standard for describing the structure and semantics of XML based documents. We will argue that these two refer to different levels of abstraction, but that, in several cases, it can be advantageous to base a document schema on an ontology. Lastly, we will show how this can be done by providing an translation procedure from an OIL ontology to a specific XML Schema. This will result in a schema that can be used to capture instances of the ontology. 123

2007

Organizations have to work with large volumes of information at different formats. In this context they are necessary tools and formats like XML, to integrate these data and solve the heterogeneity problem. In this paper we proposed a new software tool called XDS. XDS (eXtensible Data Sources) is a new system to integrate data from relational databases, native XML databases and XML documents. On the other hand, the environment of libraries has also their bibliographical catalogues at different sources and formats. Therefore, we show the use and validity of the XDS system in this environment obtaining the results in a bibliographical format like MODS (Metadata Object Description Schema). Hereby the resources of different bibliographical catalogues can be consulted obtaining the results in a common format as MODS.

2008 International Conference on Automated Solutions for Cross Media Content and Multi-Channel Distribution, 2008

The role of metadata is gaining importance due to today's growth of multimedia content. Currently, XML is the standard for data interchange. However, as XML Schemas do not express semantics but rather the document structure, there is a lack of semantic interoperability regarding current (XMLbased) metadata standards. By using Semantic Web technologies, ontologies can be created to describe the semantics of a particular metadata format. A problem is that the existing XML data (compliant with a particular metadata format) cannot be used by an ontology, implying the need for a conversion of XML data to RDF instances. In this paper, a generic approach is proposed for the transformation of XML data into RDF instances in an ontology-dependent way. By means of a mapping document, the link is described between an XML Schema (describing the structure of particular XML data) and an OWL ontology. Our approach is illustrated by applying it to the DIG35 specification, which is an XML-based metadata standard for the description of digital images.

One definition of an ontology is that it is a specification of a conceptualization that is designed for reuse across multiple applications [Gr93,Gu95]. By a conceptualization, we mean a set of concepts, relations, objects, and constraints that define a semantic model of some domain of interest. An ontology is a specification of a conceptualization in the sense that it is a formal encoding of the concepts, relations, objects, and constraints within that semantic model.

GI Jahrestagung (2), 2004

This paper addresses some classical problems to integrate data sources that are heterogeneous in structure with possibly redundant data along a real world example integrating three bibliographic data sources. We show how XML-technology can be applied for the data integration process in a straightforward manner to populate a data warehouse, how an ontology can be used as common schema, and how a generic, declarative approach can increase flexibility and scalability. Our procedure enables more advanced query functionality for integrated data sources.