“…Several works have used semantics and ontologies within smart cities for a variety of functions, e.g., to add value to data collected from sensor and social data streams [85], to combine sensor and social data streams with machine learning techniques and to facilitate interoperability and information exchange [83]. A range of projects has explored the use of the semantic web in specific domains, such as energy and transport [28], mobility and autonomous vehicles [86], traffic jams and delay [87], surveillance system [88], emergency management [89], environment [90], parking [91], energy [92,93], water [94] and so on. Several projects and frameworks have also emerged, aiming to exploit semantics to enable interoperability, e.g., OpenIoT [95], CityPulse [96] and VITAL [97].…”