Over the last few years, the number of smart objects connected to the Internet has grown exponentially in comparison to the number of services and applications. The integration between Cloud Computing and Internet of Things, named as Cloud of Things, plays a key role in managing the connected things, their data and services. One of the main challenges in Cloud of Things is the resource discovery of the smart objects and their reuse in different contexts. Most of the existent work uses some kind of multi-criteria decision analysis algorithm to perform the resource discovery, but do not evaluate the impact that the user constraints has in the final solution. In this paper, we analyse the behaviour of the SAW, TOPSIS and VIKOR multi-objective decision analyses algorithms and the impact of user constraints on them. We evaluated the quality of the proposed solutions using the Pareto-optimality concept.
With the growing popularity of Internet of Things (IoT) technologies and sensors deployment, more and more cities are leaning towards the initiative of smart cities. Smart city applications are mostly developed with aims to solve domain-specific problems. Hence, lacking the ability to automatically discover and integrate heterogeneous sensor data streams on the fly. To provide a domain-independent platform and take full benefits from semantic technologies, in this paper we present an Automated Complex Event I mplementation System (ACEIS), which serves as a middleware between sensor data streams and smart city applications. ACEIS discovers and integrates IoT streams in urban infrastructures for users' requirements expressed as complex event requests, based on semantic IoT stream descriptions. It also processes complex event patterns on the fly using semantic data streams.