Exploiting the full potential of the World Wide Web will require semantic as well as syntactic interoperability. This can best be achieved by providing a further representation and inference layer that builds on existing and proposed web standards. The OIL language extends the RDF schema standard to provide just such a layer. It combines the most attractive features of frame based languages with the expressive power, formal rigour and reasoning services of a very expressive description logic. 1

. With the aim of building a "Semantic Web", the content of the documents must be explicitly represented through metadata in order to enable contents-guided search. Our approach is to exploit a standard language (RDF, recommended by W3C) for expressing such metadata and to interpret these metadata in conceptual graphs (CG) in order to exploit querying and inferencing capabilities enabled by CG formalism. The paper presents our mapping of RDF into CG and its interest in the context of the semantic Web. 1 Introduction The Web is recognized as a fabulous information repository, with millions of heterogeneous information sources available throughout the world. But the existing keyword-based search engines do not take into account the semantics of the documents accessible through the Web. The user can be easily overwhelmed by the huge number of answers (not always relevant) to a query. Therefore, the need of a "Semantic Web" is more and more emphasized [2, 3]. The semantics of the ...

The next generation of the Web is often characterized as the "Semantic Web": information will no longer only be intended for human readers, but also for processing by machines, enabling intelligent information services, personalized Web-sites, and semantically empowered search-engines. The Semantic Web requires interoperability on the semantic level. Semantic interoperability requires standards not only for the syntactic form of documents, but also for the semantic content. Proposals aiming at semantic interoperability are the results of recent W3C standardization efforts, notably XML/XML Schema and RDF/RDF Schema. In this paper, we make the following claims: . A further representation and inference layer is needed on top of the currently available layers of the WWW. . To establish such a layer, we propose a general method for encoding arbitrary ontology representation languages into RDF/RDF Schema. . We illustrate the extension method by applying it to a particular ontolo...

parsing, unparsing, generation, grammar, universal algebra, XML, RDF It is difficult to serialize an RDF graph as a humanly readable RDF/XML document. This paper describes the approach taken in Jena 1.2, in which a design pattern of guarded procedures invoked using top-down recursive descent is used. Each procedure corresponds to a grammar rule; the guard makes the choice about the applicability of the production. This approach is seen to correspond closely to the design of an LL(k) parser, and a theoretical justification of this correspondence is found in universal algebra.

. The CoMMA project (Corporate Memory Management through Agents) aims at developing an open, agent-based platform for the management of a corporate memory by using the most advanced results on the technical, the content, and the user interaction level. We focus here on methodologies for the set-up of multi-agent systems, requirement engineering and knowledge acquisition approaches. 1. Introduction How to improve access, share and reuse of both internal and external knowledge in a company? How to improve newcomers' learning and integration in a company? How to enhance technology monitoring in a company? Knowledge Management (KM) aims at solving such problems. Different research communities offer - partial - solutions for supporting KM. The integration of results from these different research fields seems to be a promising approach. This is the motivation of the CoMMA IST project-funded by the European Commission- which started February 2000. The main objective is to implement and ...

Many approaches for retrieving the images semantically have been proposed. There still have many known limitations. The key problem is the identification of appropriate concepts. In this paper, we introduce the new image retrieval system that employs a concept based technique utilizing ontology. There are many attempts to search images using ontology. However, they haven’t given the much good results. The reason is that the ontology just has been used to resolve the conceptual heterogeneous between the text annotations. Another reason is to use the much big ontology. To improve the accuracy in terms of precision and recall of an image retrieval system we have created a personalized ontology and spatial ontology. In trial implementation of our system we have achieved a level of accuracy at which was up to 83.9%. 1

Abstract. Semistructured data is now widely used in both web applications and database systems. Much of the research into this area defines algorithms that transform the data and schema, such as data integration, change management, view definition, and data normalization. While some researchers have defined a formalism for the work they have undertaken, there is no widely accepted formalism that can be used for the comparison of algorithms within these areas. The requirements of a formalism that would be helpful in these situations are that it must capture all the necessary semantics required to model the algorithms, it should not be too complex and it should be easy to use. This paper describes a first step in defining such a formalism. We have modelled the semantics expressed in the ORA-SS (Object Relationship Attribute data model for SemiStructured data) data modelling notation in two formal languages that have automatic verification tools. We compare the two models and present the findings.

Abstract – The paper presents an original survey on Web ontology editing tools, in respect with Semantic Web actual technologies. The material is focused on features that these tools might expose: granularity of expressivity, Web standards compliance, reasoning support, provided APIs and, not least, the interoperability issues. The comparative study is used a specific test ontology regarding the main characteristics and features of Semantic Web applications.

Abstract. We introduce an online knowledge base for semantic representation and annotation of a world heritage site in danger. For this purpose we designed ontology inside the protégé tool with multiple metadata-based schemas to represent a knowledge base for heritage buildings and to annotate heterogeneous data sources. The ontology schema also references multiple bibliographies so it can gather the complex history of each building, or multiple coordinated locations of each building. We built an ontology-driven Website generation system “Bam3DCG ” based on the Resource Description Framework graph exported from Protégé, and discuss practical problems for this type of system.

Resource Description Framework (RDF) is a general description technology that can be applied to many application domains. Redland is a software library for RDF which implements a flexible framework that complements this power and provides a high-level interface allowing instances of the RDF model to be stored, queried and manipulated. Redland implements the model concepts using an objectbased API and provides several of the classes as modules which can be added, removed or replaced to provide different functionality or application-specific optimisations. The framework also provides a core technology for developing new RDF applications that can experiment with implementation techniques, APIs and representation issues. Keywords: RDF, metadata, application framework 1 Introduction RDF[1] is a general purpose technology that enables the description of resources on the web using URIs for identifying the resources and URIs for the properties that describe the resources. This desi...