Producing Linked Data for Smart Cities: The Case of Catania

Semantic Web technologies and in particular Linked Open Data provide a means for sharing knowledge about cities as physical, social, and technical systems, so enabling the development of smart city applications. This paper presents the case of Catania with the aim of sharing the lessons learnt, which can be reused as reference practices in other cases with similar requirements. The importance of achieving syntactic as well as semantic interoperability as a result of transforming heterogeneous sources into Linked Data is discussed: semantic interoperability must be solved at data level in order to ease the development of smart city applications. This claim is supported by showing how this issue impacts on the design of two smart city applications. As main contributions, the paper describes: (i) methods, procedures, and tools used for transforming heterogeneous sources into Linked Data; (ii) an ontology design pattern for modelling urban public transportation routes; (iii) methods, procedures and tools for ensuring semantic interoperability during the transformation process; (iv) the design of two smart city applications based on Linked Data. All produced data, models, and prototypes are publicly accessible online.