For data practitioners embracing the world of RDF and Linked Data, the openness and flexibility is a mixed blessing. For them, data validation according to predefined constraints is a much sought-after feature, particularly as this is taken for granted in the XML world. Based on our work in the DCMI RDF Application Profiles Task Group and in cooperation with the W3C Data Shapes Working Group, we published by today 81 types of constraints that are required by various stakeholders for data applications. These constraint types form the basis to investigate the role that reasoning and different semantics play in practical data validation, why reasoning is beneficial for RDF validation, and how to overcome the major shortcomings when validating RDF data by performing reasoning prior to validation. For each constraint type, we examine (1) if reasoning may improve data quality, (2) how efficient in terms of runtime validation is performed with and without reasoning, and (3) if validation results depend on underlying semantics which differs between reasoning and validation. Using these findings, we determine for the most common constraint languages which constraint types they enable to express and give directions for the further development of constraint languages.

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The UV spectrum and the absorption cross sections of carbonyl fluoride (COF2) have been measured in the wavelength range 200 – 230 nm at 296 K with a resolution of 0.03 nm by diode array spectroscopy. Preliminary results of the determination of the quantum yield of COF2 at 193 nm and 296 K are presented. The new absorption cross sections and the new estimate of the quantum yield were used to calculate photodissociation rate constants at solar zenith angles ranging from 0° to 86° as a function of height (0 – 55 km).

Methods to design of formal ontologies have been in focus of research since the early nineties when their importance and conceivable practical application in engineering sciences had been understood. However, often significant customization of generic methodologies is required when they are applied in tangible scenarios. In this paper, we present a methodology for ontology design developed in the context of data integration. In this scenario, a targeting ontology is applied as a mediator for distinct schemas of individual data sources and, furthermore, as a reference schema for federated data queries. The methodology has been used and evaluated in a case study aiming at integration of buildings' energy and carbon emission related data. We claim that we have made the design process much more efficient and that there is a high potential to reuse the methodology.

This paper presents Map-On, a web-based editor for visual ontology mapping developed at the Architecture, Representation and Computation research group of the La Salle at Ramon Llull University. The Map-On editor provides a graphical environment for ontology mapping creation based on the representation of mapping using an interactive graph layout. Thus, a point-and-click interface simplifies the mapping creation process. Based on the user inputs the editor automatically generates a R2RML document, particularly produces the IRI patterns and the SQL queries. It has been used in real scenarios alleviating the effort of coding R2RML statements which is one of the main barriers for adopting R2RML in research and in the industry communities.