Development of Reconfigurable Distributed Embedded Systems with a Model-Driven Approach

International audienceIn this paper, we propose a model-driven approach allowing to build reconfigurable distributed real-time embedded (DRE) systems. The constant growth of the complexity and the required autonomy of embedded software systems management give the dynamic reconfiguration a big importance. New challenges to apply the dynamic reconfiguration at model level as well as runtime support level are required. In this direction, the development of reconfigurable DRE systems according to traditional processes is not applicable. New methods are required to build and to supply reconfigurable embedded software architectures. In this context, we propose an model-driven engineering based approach that enables to design reconfigurable DRE systems with execution framework support. This approach leads the designer to specify step by step his/her system from a model to another one more refined until the targeted model is reached. This targeted model is related to a specific platform leading to the generation of the most part of the system implementation. We also develop a new middleware that supports reconfigurable DRE systems

A New Model-Based Framework for Testing Security of IOT Systems in Smart Cities Using Attack Trees and Price Timed Automata

International audienceIn this paper we propose a new model-based framework for testing security properties of Internet of Things in Smart Cities. In general a model-based approach consists in extracting test cases from a formal specification either of the system under test or the environment of the considered system in an automatic fashion. Our framework is mainly built on the use of two formalisms namely Attack Trees and Price Timed Automata. An attack tree allows to describe the strategy adopted by the malicious party which intends to violate the security of the considered IOT system. An attack tree is translated into a network of price timed automata. The product of the constructed price timed automata is then computed using the well known UPPAALL platform. The obtained timed automata product serves as input for the adopted test generation algorithm. Moreover our framework takes advantage of the use of the standardized specification and execution testing language TTCN-3. With this respect, the obtained abstract tests are translated into the TTCN-3 format. Finally we propose a cloud-oriented architecture in order to ensure test execution and to collect the generated verdicts

Towards a Runtime Standard-Based Testing Framework for Dynamic Distributed Information Systems

International audienceIn this work, we are interested in testing dynamic distributed information systems. That is we consider a decentralized information system which can evolve over time. For this purpose we propose a runtime standard-based test execution platform. The latter is built upon the normalized TTCN-3 specification and implementation testing language. The proposed platform ensures execution of tests cases at runtime. Moreover it considers both structural and behavioral adaptations of the system under test. In addition, it is equipped with a test isolation layer that minimizes the risk of interference between business and testing processes. The platform also generates a minimal subset of test scenarios to execute after each adaptation. Finally, it proposes an optimal strategy to place the TTCN-3 test components among the system execution nodes

Overcoming Non-determinism in Testing Smart Devices: A Case Study

This paper presents a case study in ”black-box” assessment of a ”smart” device where, based only on the user manuals and the instrument itself, we try to build confidence in smart device reliability. To perform the black-box assessment, we developed a test environment which automates the generation of test data, their execution and interpretation of the results. The assessment was made more complex by the inherent non-determinism of the device. For example, non-determinism can arise due to inaccuracy in an analogue measurement made by the device when two alternative actions are possible depending on the measured value. This non-determinism makes it difficult to predict the output values that are expected from a test sequence of analogue input values. The paper presents two approaches to dealing with this difficulty: (1) based on avoidance of test values that could have multiple responses, (2) based on consideration of all possible interpretations of input data. To support the second approach we use advanced modelling and simulation techniques to predict all the likely interpretations and check whether any of them is observed at the smart device output

Sustainable maritime crude oil transportation: a split pickup and split delivery problem with time windows

This paper studies a novel sustainable vessel routing problem modeling considering the multi-compartment, split pickup and split delivery, and time windows concepts. In the presented problem, oil tankers transport crude oil from supply ports to demand ports around the globe. The objective is to find ship routes, as well as port arrival and departure times, in a way that minimizes transportation costs. As a second objective, we considered the sustainability aspect by minimizing the vessel energy efficiency operational indicator. Multiple products are transported by a heterogeneous fleet of tankers. Small realistic test instances are solved with the exact method

Spectral properties for polynomial and matrix operators involving demicompactness classes

The first aim of this paper is to show that a polynomially demicompact operator satisfying certain conditions is demicompact. Furthermore, we give a refinement of the Schmoëger and the Rakocević essential spectra of a closed linear operator involving the class of demicompact ones. The second aim of this work is devoted to provide some sufficient conditions on the inputs of a closable block operator matrix to ensure the demicompactness of its closure. An example involving the Caputo derivative of fractional of order α is provided. Moreover, a study of the essential spectra and an investigation of some perturbation results.peerReviewe

Genetic Algorithms for Optimal Reactive Power Compensation of a Power System with Wind Generators based on Artificial Neural Networks

In this paper, we develop a method to maintain an acceptable voltages profile and minimization of active losses of a power system including wind generators in real time. These tasks are ensured by acting on capacitor and inductance benches implemented in the consuming nodes. To solve this problem, we minimize an objective function associated to active losses under constraints imposed on the voltages and the reactive productions of the various benches. The minimization procedure was realised by the use of genetic algorithms (GA). The major disadvantage of this technique is that it requires a significant computing time thus not making it possible to deal with the problem in real time. After a training phase, a neural model has the capacity to provide a good estimation of the voltages, the reactive productions and the losses for forecast curves of the load and the wind speed, in real time