Catálogo de publicaciones - libros

The deployment of multi-tiered applications in large-scale environments remains a difficult task: the architecture of these applications is complex and the target environment is heterogeneous, open and dynamic. In this paper, we show how the component-based approach simplifies the design, the deployment and the reconfiguration of a J2EE system. We propose an architecture description language that allows specifying constraints on the resources needed by the components and on their location, and a deployment solution that handles failures.

Web applications are tightly coupled with the platforms that a particular service provider intends to support and the execution scenario envisioned at the design time. Consequently, the resulting applications do not adapt well to all clients and runtime execution contexts. The goal of our research is to develop methods and software to support which can be customized to specific requirements. Thinking in terms of [2], we need a product line for a given Web application, each instance of which is for a specific execution platform and context. To achieve such a product line, we have to satisfy two requirements: universal accessibility and context-dependent component distribution.

Service-Oriented Computing (SOC) is emerging as a promising software development paradigm based on the concept of encapsulating application logic within independent, loosely coupled, stateless services that interact via messages using standard communication protocols. The design principles of SOC are yet to be well understood; therefore service-oriented systems are often developed in an ad-hoc fashion, with little support for validating the quality of the service-oriented (SO) design upon which such systems are based. As such, there is a need for mechanisms supporting the measurement of internal structural quality attributes of SO designs (such as coupling and cohesion) in order to predict and enhance the quality of the final product.

ODESeW allows developing ontology-based Web portals. We describe the functionalities offered by a specific deployment of the ODESeW application development platform, oriented to the management of EU R&D projects. As an example of this specific deployment, we focus on the project management functionalities currently provided for the EU KnowledgeWeb Network of Excellence (NoE).

An is a ( an ontology simply based on a hierarchy of concepts and a hierarchy of relations) enriched with axioms used to fix the semantic interpretation of concepts and relations. Such an ontology can be a domain ontology, an ontology of representation, an ontology of PSM, etc. In our work, we argue in favor of using a graph-based solution to deal with the different activities related to Heavyweight Ontology Engineering, in particular ontology representation, ontology operationalisation, ontology evaluation ( verification and validation) and ontology matching. Our approach consists in using the graph-based paradigm to represent all the components of an heavyweight ontology ( Concepts, Relations and Axioms) and using graph homomorphism techniques to compare (at the conceptual level) the core components of an heavyweight ontology: the Axioms. This explicit graph-based representation of axioms coupled with reasoning capabilities based on graphs homomorphism facilitates both (1) the definition of important notions for Heavyweight Ontology Engineering such as or and (2) the topological comparison of axioms, which in our work is used to define a new approach of ontology matching mainly based on axiom-based ontology morphisms.

An ontology is [1]. Ontologies are seen as important technique for semantic data processing, and in particular for interoperability. As they represent knowledge about a certain evolving real world domain the ontologies have to evolve as well. Knowledge about the changes is mandatory to correctly interpret data or documents based on the semantics defined in the ontology. Furthermore, the correct comparison of data and documents from different points in time, based on different versions of an ontology is only possible if the differences between these versions are known.

News feeds using RDF Site Summary (RSS) are becoming common-place for news providers on the Internet. Using a news aggregator, users can stay informed about the topics they are interested in without having to constantly check the actual web pages themselves. This near instant availability of a plethora of news sources poses new challenges: filtering and categorisation techniques are needed that adapt to changing information needs of the users as well as to the changes occurring in the topics reported on. This paper presents an approach to filtering news feeds relevant to a set of interests using ad-hoc ontologies. These filters are created from a small core-ontology describing topics of articles the user is interested in.

A catalog holds information about a set of objects, typically classified using terms taken from a given thesaurus. Mediated access to a collection of catalogs over the same domain therefore requires some strategy to deal with multiple thesauri, which represent different classifications for the same domain. This paper proposes an approach using online mapping rate estimations to define weighted relationships between terms of distinct thesauri. The mediator then uses such relationships to remap keyword-based queries to the different catalogs. Moreover, query answers provide valuable feedback to adjust the relationship weights, thereby improving the mediator accuracy.

Usually, online games cannot adapt to the dynamic change of population. In this paper, we propose a new dynamic load balancing approach for online games using predefined area information. To control dynamic change of population, it divides or merges fields considering the surveyed load based on predefined area information. By the simple modification to this information, we can easily control problems that come from changes of map data, changes of resources’ status, or changes of user’s behavior pattern.

Within grid environments, as the number of remote operations increases, the latencies for these operations become a dominant factor for application performance. Bulk operations represent one potential methodology to reduce latencies for large numbers of similar operations. However, the identification of bulks can pose a non-trivial exercise for application developers, often implying changes in the remote API, and hence direct code modifications to the application.