Drones for smart cities

Smart cities and unmanned aerial vehicles (UAVs) are two relatively recent concepts and also hot topics in research. The combination of these two technologies is expected to propel their capabilities even further for enabling revolutionary applications that will improve our quality of life. This Special Issue focuses on novel work done on the application of UAVs where state-of-the-art technologies in sensing, information dissemination, communications, and artificial intelligence (AI) are applied within the context of smart cities..

Integrating Usage Control with SIP-Based Communications

The Session Initiation Protocol (SIP) is a signaling protocol used for establishing and maintaining communication sessions involving two or more participants. SIP was initially designed for voice over IP and multimedia conferencing, and then was extended to support other services such as instant messaging and presence management. Today, SIP is also adopted to be used with 3G wireless networks, thus it becomes an integral protocol for ubiquitous environment. SIP has various methods that support a variety of applications such as subscribing to a service, notification of an event, status update, and location and presence services. However, when it comes to security, the use of wireless and mobile communication technologies and the pervasive nature of this environment introduce higher risks to security than that of the old simple environment. In this paper, we introduce new architecture that implements a new type of access control called usage access control (UCON) to control the access to the SIP-based communication at preconnection, during connection, and postconnection. This will enable prescribers of SIP services to control who can identify their locations to approve or disapprove their subsequent connections, and to also set some parameters to determine whether a certain communication can continue or should terminate

A Formal Approach to the Design of QoS Parameters in Multimedia Systems

In this paper we introduce a new approach to the formal design and modelling of QoS parameters in multimedia systems. This approach is based on the principle of separation of concerns. We use the process algebra based language LOTOS to specify the functional behaviour of the system and separately describe the quality of service requirements using an appropriate temporal logic. This temporal logic integrates real-time and stochastic constructs to enable the expression of QoS parameters such as deadlines, jitter and error rates. The specifications are then linked together in the same model. We also define a mapping from temporal logic statements to event schedulers. These schedulers can then be used to monitor the events that occur in the system and ensure that the system's behaviour achieves the QoS requirements. 1 Introduction Over the past few years a wide range of distributed systems has emerged to support multimedia applications. These systems are characterized by the processing an..

Specification of Stochastic Properties in Real-Time Systems.

In this paper we present a new approach to the formal specification of distributed real-time systems using the formal description technique LOTOS together with a stochastic temporal logic STL. This approach previously presented in the context of LOTOS/QTL, is characterized by a separation of concerns. The functional behaviour is described in LOTOS without regard for the time critical constraints. The specification is then extended with precise real-time requirements written in STL. We present a method to generate a timing event scheduler from the requirements in order to monitor the functional behaviour. 1 Introduction Over the past few years there have been several techniques used for the design and the validation of distributed systems. Traditionally, these techniques fall into two distinct fields: qualitative validation and quantitative evaluation. The former field is concerned by the formal correctness of the system and usually employs formal description techniques. These techni..