A Double Classification of Common Pitfalls in Ontologies

The application of methodologies for building ontologies has improved the ontology quality. However, such a quality is not totally guaranteed because of the difficulties involved in ontology modelling. These difficulties are related to the inclusion of anomalies or worst practices in the modelling. In this context, our aim in this paper is twofold: (1) to provide a catalogue of common worst practices, which we call pitfalls, and (2) to present a double classification of such pitfalls. These two products will serve in the ontology development in two ways: (a) to avoid the appearance of pitfalls in the ontology modelling, and (b) to evaluate and correct ontologies to improve their quality

Model-driven design, simulation and implementation of service compositions in COSMO

The success of software development projects to a large extent depends on the quality of the models that are produced in the development process, which in turn depends on the conceptual and practical support that is available for modelling, design and analysis. This paper focuses on model-driven support for service-oriented software development. In particular, it addresses how services and compositions of services can be designed, simulated and implemented. The support presented is part of a larger framework, called COSMO (COnceptual Service MOdelling). Whereas in previous work we reported on the conceptual support provided by COSMO, in this paper we proceed with a discussion of the practical support that has been developed. We show how reference models (model types) and guidelines (design steps) can be iteratively applied to design service compositions at a platform independent level and discuss what tool support is available for the design and analysis during this phase. Next, we present some techniques to transform a platform independent service composition model to an implementation in terms of BPEL and WSDL. We use the mediation scenario of the SWS challenge (concerning the establishment of a purchase order between two companies) to illustrate our application of the COSMO framework

Methods and Tools for Management of Distributed Event Processing Applications

Die Erfassung und Verarbeitung von Ereignissen aus cyber-physischen Systemen bietet Anwendern die Möglichkeit, kontinuierlich über Leistungsdaten und aufkommende Probleme unterrichtet zu werden (Situational Awareness) oder Wartungsprozesse zustandsabhängig zu optimieren (Condition-based Maintenance). Derartige Szenarien verlangen aufgrund der Vielzahl und Frequenz der Daten sowie der Anforderung einer echtzeitnahen Auswertung den Einsatz geeigneter Technologien. Unter dem Namen Event Processing haben sich dabei Technologien etabliert, die in der Lage sind, Datenströme in Echtzeit zu verarbeiten und komplexe Ereignismuster auf Basis räumlicher, zeitlicher oder kausaler Zusammenhänge zu erkennen. Gleichzeitig sind heute in diesem Bereich verfügbare Systeme jedoch noch durch eine hohe technische Komplexität der zugrunde liegenden deklarativen Sprachen gekennzeichnet, die bei der Entwicklung echtzeitfähiger Anwendungen zu langsamen Entwicklungszyklen aufgrund notwendiger technischer Expertise führt. Gerade diese Anwendungen weisen allerdings häufig eine hohe Dynamik in Bezug auf Veränderungen von Anforderungen der zu erkennenden Situationen, aber auch der zugrunde liegenden Sensordaten hinsichtlich ihrer Syntax und Semantik auf. Der primäre Beitrag dieser Arbeit ermöglicht Fachanwendern durch die Abstraktion von technischen Details, selbständig verteilte echtzeitfähige Anwendungen in Form von sogenannten Echtzeit-Verarbeitungspipelines zu erstellen, zu bearbeiten und auszuführen. Die Beiträge der Arbeit lassen sich wie folgt zusammenfassen: 1. Eine Methodik zur Entwicklung echtzeitfähiger Anwendungen unter Berücksichtigung von Erweiterbarkeit sowie der Zugänglichkeit für Fachanwender. 2. Modelle zur semantischen Beschreibung der Charakteristika von Ereignisproduzenten, Ereignisverarbeitungseinheiten und Ereigniskonsumenten. 3. Ein System zur Ausführung von Verarbeitungspipelines bestehend aus geographisch verteilten Ereignisverarbeitungseinheiten. 4. Ein Software-Artefakt zur graphischen Modellierung von Verarbeitungspipelines sowie deren automatisierter Ausführung. Die Beiträge werden in verschiedenen Szenarien aus den Bereichen Produktion und Logistik vorgestellt, angewendet und evaluiert

FLACOS’08 Workshop proceedings

The 2nd Workshop on Formal Languages and Analysis of Contract-Oriented Software (FLACOS’08) is held in Malta. The aim of the workshop is to bring together researchers and practitioners working on language-based solutions to contract-oriented software development. The workshop is partially funded by the Nordunet3 project “COSoDIS” (Contract-Oriented Software Development for Internet Services) and it attracted 25 participants. The program consists of 4 regular papers and 10 invited participant presentations

Semantic Services Grid in Flood-forecasting Simulations

Flooding in the major river basins of Central Europe is a recurrent event affecting many countries. Almost every year, it takes away lives and causes damage to infrastructure, agricultural and industrial production, and severely affects socio-economic development. Recurring floods of the magnitude and frequency observed in this region is a significant impediment, which requires rapid development of more flexible and effective flood-forecasting systems. In this paper we present design and development of the flood-forecasting system based on the Semantic Grid services. We will highlight the corresponding architecture, discovery and composition of services into workflows and semantic tools supporting the users in evaluating the results of the flood simulations. We will describe in detail the challenges of the flood-forecasting application and corresponding design and development of the service-oriented model, which is based on the well known Web Service Resource Framework (WSRF). Semantic descriptions of the WSRF services will be presented as well as the architecture, which exploits semantics in the discovery and composition of services. Further, we will demonstrate how experience management solutions can help in the process of service discovery and user support. The system provides a unique bottom-up approach in the Semantic Grids by combining the advances of semantic web services and grid architectures