# Ontological Representation of Smart City Data: From Devices to Cities
## 4 Ontology Design Patterns Proposal for Smart City Ontologies  
Table 5 shows that several domains are represented by the analyzed ontologies. However, it can be observed that no ontology covers all the core domains for smart cities. Given this situation, it is advisable to provide a common conceptualization that involves such domains in order to represent the data potentially involved in smart city use cases. As mentioned in the Introduction, this work is devoted to provide a list of domain-dependent patterns, specifically named ODPs. In order to provide a set of ontological requirements for each core domain, an ontological reverse engineering has been performed. In this process, some smart city-related initiatives developed by standardization bodies, associations, and European projects have been taken into account. More precisely, the process is based on data models, ontologies, datasets, and standards provided by OGC (Open Geospatial Consortium [[http://www.opengeospatial.org](http://www.opengeospatial.org)]([http://www.opengeospatial.org](http://www.opengeospatial.org))), \begin{table}
\begin{tabular}{c c c c c c c} \hline
**Ontologies Domains** & **Administrative Area** & **City Object** & **Event** & **KPI** & **Public Service** & **Topology** & **Observations/ Measurements** \\ \hline \hline \multicolumn{1}{c}{festa-iot} & ✓ & & & ✓ & ✓ \\ \hline \hline \multicolumn{1}{c}{gci} & ✓ & & ✓ & ✓ & ✓ & ✓ \\ \hline \hline \multicolumn{1}{c}{km4c} & ✓ & ✓ & ✓ & ✓ & ✓ & ✓ \\ \hline \hline \multicolumn{1}{c}{oldssn} & ✓ & & & & & ✓ \\ \hline \hline \multicolumn{1}{c}{sao} & ✓ & ✓ & & & & ✓ \\ \hline \hline \multicolumn{1}{c}{san} & ✓ & & & & & ✓ \\ \hline \hline \multicolumn{1}{c}{saref} & ✓ & & & & ✓ & ✓ \\ \hline \hline \multicolumn{1}{c}{sco} & ✓ & & & ✓ & ✓ & ✓ \\ \hline \hline \multicolumn{1}{c}{sctc} & ✓ & & & ✓ & ✓ & ✓ \\ \hline \hline \multicolumn{1}{c}{seas/pep} & ✓ & & & & & \\ \hline \hline \multicolumn{1}{c}{smart-city} & ✓ & ✓ & ✓ & ✓ & ✓ & \\ \hline \hline \multicolumn{1}{c}{ssn/sosa} & ✓ & & & & & ✓ \\ \hline \hline \multicolumn{1}{c}{vital} & ✓ & & & ✓ & ✓ & ✓ \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Domains represented in smart city ontologies. FEMP (Spanish Federation of Municipalities and Provinces [[http://www.femp.es](http://www.femp.es)]([http://www.femp.es](http://www.femp.es))), ISO (International Organization for Standardization [[https://www.iso.org](https://www.iso.org)]([https://www.iso.org](https://www.iso.org))), FIWARE (A software platform for smart cities [[https://www.fiware.org](https://www.fiware.org)]([https://www.fiware.org](https://www.fiware.org))), and AENOR (Spanish Association for Normalization [[https://www.aenor.com](https://www.aenor.com)]([https://www.aenor.com](https://www.aenor.com))). Such a list of ontologies' requirements has been taken in the present survey as input in order to: (a) observe whether the analyzed ontologies model the given domains and to what extent and (b) propose a list of general ontological patterns to fulfill the proposed requirements. Taking all this information and inputs into account, a list of ODPs for smart city ontologies has been developed in order to support the reuse and to ease the ontology design and conceptualization activities. With the purpose of describing each ODP, a unified template, adapted from [48], was designed. The template consists of the following fields:  
* name: the given name for the pattern. * description: a natural language explanation of the domain addressed by the pattern. * requirements: the ontological requirements that the pattern addresses. * graphical representation: a diagram to describe the structure of the pattern, depicted by means of UML-based notation, as explained in [49]. * use case: an example about how this pattern can be applied. * note: remarks for clarifying some aspects of the pattern. According to the ontological requirements, classes, and properties have been identified in order to model the ODPs.