Modeling a distributed Heterogeneous Communication System using Parametric Timed Automata

In this report, we study the application of the Parametric Timed Automata(PTA) tool to a concrete case of a distributed Heterogeneous Communication System (HCS). The description and requirements of HCS are presented and the system modeling is explained carefully. The system models are developed in UPPAAL and validated by different test cases. Part of the system models are then converted into parametric timed automata and the schedulability checking is run to produce the schedulability regions

Parametric Real-Time System Feasibility Analysis Using Parametric Timed Automata

Real-time applications are playing an increasingly significant role in our life. The cost and risk involved in their design leads to the need for a correct and robust modelling of the system before its deployment. Many approaches have been proposed to verify the schedulability of real-time task system. A frequent limitation is that they force the task activation to restrictive patterns (e.g. periodic). Furthermore, the type of analysis carried out by the real-time scheduling theory relies on restrictive assumptions that could make the designers miss important optimization opportunities. On the other hand, the application of formal methods for verification of timed systems typically produces a yes/no answer that does not suggest any correction action or robustness margins of a given design. This work proposes an approach to combine the benefits of formal method in terms of flexibility with the production of a clear feedback for the designers. The key idea is to use parametric timed automata to enable the definition of flexible task activation patterns. The Parametric Verification of Temporal Properties (PTVP) algorithm proposed in this work produces a region of feasible parameters for realtime system. All the parameter valuation within this region is guaranteed to make the system respect the desired temporal behaviour. In this way developers are provided with a richer information than the simple feasibility of a given design choice. This method uses symbolic model checking technique to produce the result that is a union of polyhedral regions in the parameter space associated with feasible parameters. It is implemented in the tool Quinq that is based on NuSMV3. The tool also implemented an optimization to speed up the search, such as using non-parametric model checker to find counterexamples (i.e. traces) related to the unfeasible choices of parameters. Two applications of the tool and of the underlying method to several real-time system examples are presented in this dissertation : periodic real-time system tasks with offset and heterogeneous distributed real-time systems. A work that applies the tool in collaboration with another real-time system analysis tool, Modular Performance Analysis Toolbox, is also presented to show one of the many possible application of the method presented in this work. In this work we also compare our approach to the state of the art in the field of sensitivity analysis of real-time systems. However, compared to the other tools and approaches in this field, the method offered in this work presents unique advantages in the generality of the system modelling approach and the possibility to analyse the entire region of feasibility of any desired parameter in the system

Symbolic Computation of Schedulability Regions using Parametric Timed Automata

In this paper, we address the problem of symbolically computing the region in the parameter’s space that guarantees a feasible schedule, given a set of real-time tasks characterised by a set of parameters and by an activation pattern. We make three main contributions. First, we propose a novel and general method, based on parametric timed automata. Second, we prove that the algorithm terminates for the case of periodic processes with bounded offsets. Third, we provide an implementation based on the use of symbolic model checking techniques for parametric timed automata, and present some case studies

The Mobile Territorial Lab: A multilayered and dynamic view on parents' daily lives

none11siThe exploration of people’s everyday life has long been of interest to social scientists. Recent years have witnessed a growing interest in analyzing human behavioral data generated by technology (e.g. mobile phones). To date, a few large-scale studies have been designed to measure human behaviors and interactions using multiple sources of data. A common characteristic of these studies is the population under investigation: students having similar daily routines and needs. This choice constraints the range of behaviors, of places and the generalization of the results. In order to widen this line of studies, we focus on a different target group: parents with young children aged 0 through 10 years. Children influence multiple aspects of their parents’ lives, from the satisfaction of basic human needs and the fulfillment of social roles to their financial status and sleep quality. In this paper, we describe the Mobile Territorial Lab (MTL) project, a longitudinal living lab which has been sensing by means of technology (mobile phones) the lives of more than 100 parents in different areas of the Trentino region in Northern Italy. We present the preliminary results after two years of experimentation of, to the best of our knowledge, the most complete picture of parents’ daily lives. Through the collection and analysis of the collected data, we created a multi-layered view of the participants’ lives, tracking social interactions, mobility routines, spending patterns, and personality characteristics. Overall, our results prove the relevance of living lab approaches to measure human behaviors and interactions, which can pave the way to new studies exploiting a richer number of behavioral indicators. Moreover, we believe that the proposed methodology and the collected data could be very valuable for researchers from different disciplines such as social psychology, sociology, computer science, economy, etc., which are interested in understanding human behaviour.Centellegher, Simone; De Nadai, Marco; Caraviello, Michele; Leonardi, Chiara; Vescovi, Michele; Ramadian, Yusi; Oliver, Nuria; Pianesi, Fabio; Pentland, Alex; Antonelli, Fabrizio; Lepri, BrunoCentellegher, Simone; De Nadai, Marco; Caraviello, Michele; Leonardi, Chiara; Vescovi, Michele; Ramadian, Yusi; Oliver, Nuria; Pianesi, Fabio; Pentland, Alex; Antonelli, Fabrizio; Lepri, Brun