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International audience ; In this era of big data, of quantified self and of smart cities, wireless sensor networks are meant to be used every day, for all sort of applications. Made of tiny sensors, they collect data and communicate through wireless technologies. Because they may take part in sensitive or military applications, security is an essential matter in such networks. Confidentiality and authenticity can be ensured by the use of dedicated mechanisms. Focusing on availability, we propose here a new practical approach to protect the network against denial of service attacks thanks to the use of traffic monitoring agents called cNodes. The approach uses a fair election process of cNodes in accordance with classical criteria related to residual energies and the presence of compromised nodes which may have greedy or jamming behaviors. Results obtained from simulations show that this method is effective both in terms of detection and of energy conservation.

International audience ; In this era of big data, of quantified self and of smart cities, wireless sensor networks are meant to be used every day, for all sort of applications. Made of tiny sensors, they collect data and communicate through wireless technologies. Because they may take part in sensitive or military applications, security is an essential matter in such networks. Confidentiality and authenticity can be ensured by the use of dedicated mechanisms. Focusing on availability, we propose here a new practical approach to protect the network against denial of service attacks thanks to the use of traffic monitoring agents called cNodes. The approach uses a fair election process of cNodes in accordance with classical criteria related to residual energies and the presence of compromised nodes which may have greedy or jamming behaviors. Results obtained from simulations show that this method is effective both in terms of detection and of energy conservation.

International audience ; In this era of big data, of quantified self and of smart cities, wireless sensor networks are meant to be used every day, for all sort of applications. Made of tiny sensors, they collect data and communicate through wireless technologies. Because they may take part in sensitive or military applications, security is an essential matter in such networks. Confidentiality and authenticity can be ensured by the use of dedicated mechanisms. Focusing on availability, we propose here a new practical approach to protect the network against denial of service attacks thanks to the use of traffic monitoring agents called cNodes. The approach uses a fair election process of cNodes in accordance with classical criteria related to residual energies and the presence of compromised nodes which may have greedy or jamming behaviors. Results obtained from simulations show that this method is effective both in terms of detection and of energy conservation.

In project management process, the objective is to define and develop a model for planning, scheduling, controlling, and monitoring different activities of a particular project. Time scheduling plays an important role in successful implementation of various activities and general outcome of project. In practice, various factors cause projects to suffer from time delay in accomplishing the activities. One important reason is imprecise knowledge about time duration of activities. This study addresses the problem of project scheduling in uncertain resource environments, which are defined by uncertain activity durations. The study presents a solution of the levelling and allocation problems for projects that have some uncertain activities. The resources are minimised using resource levelling based on a proposed heuristic algorithm with limited duration. The algorithm performs the resource scheduling (levelling and allocation) for minimum moments. The efficiency of the proposed algorithm is indicated by the resource improvement coefficient and rate of resource utilisation.

International audience ; Sensor networks have been increasingly deployed for civil and military applications over the last years. Due to their low resources, sensors come along with new issues regarding network security and energy consumption. Focusing on the network availability, previous studies proposed to protect the network against denial of service attacks with the use of traffic monitoring agents. Working on the election process, we try to enhance this solution by introducing an energy-aware and secure method to dynamically select these "cNodes" in a clustered WSN: nodes with the higher residual energy get elected. We discuss limitations of this deterministic selection and suggest to designate new control nodes, "vNodes", to monitor the cNodes by periodically enquiring about their remaining energy, thus ensuring that they do not lie during the election process in attempt to keep their role. Validation is first carried out with a formal specification of our proposal using the UPPAAL model-checker. We model nodes by means of communicating timed automata, logical clocks and timing constraints. Through Computation Tree Logic we express and check properties for the election processes, related to energy and presence of greedy or jamming nodes.

International audience ; Sensor networks have been increasingly deployed for civil and military applications over the last years. Due to their low resources, sensors come along with new issues regarding network security and energy consumption. Focusing on the network availability, previous studies proposed to protect the network against denial of service attacks with the use of traffic monitoring agents. Working on the election process, we try to enhance this solution by introducing an energy-aware and secure method to dynamically select these "cNodes" in a clustered WSN: nodes with the higher residual energy get elected. We discuss limitations of this deterministic selection and suggest to designate new control nodes, "vNodes", to monitor the cNodes by periodically enquiring about their remaining energy, thus ensuring that they do not lie during the election process in attempt to keep their role. Validation is first carried out with a formal specification of our proposal using the UPPAAL model-checker. We model nodes by means of communicating timed automata, logical clocks and timing constraints. Through Computation Tree Logic we express and check properties for the election processes, related to energy and presence of greedy or jamming nodes.

International audience ; Sensor networks have been increasingly deployed for civil and military applications over the last years. Due to their low resources, sensors come along with new issues regarding network security and energy consumption. Focusing on the network availability, previous studies proposed to protect the network against denial of service attacks with the use of traffic monitoring agents. Working on the election process, we try to enhance this solution by introducing an energy-aware and secure method to dynamically select these "cNodes" in a clustered WSN: nodes with the higher residual energy get elected. We discuss limitations of this deterministic selection and suggest to designate new control nodes, "vNodes", to monitor the cNodes by periodically enquiring about their remaining energy, thus ensuring that they do not lie during the election process in attempt to keep their role. Validation is first carried out with a formal specification of our proposal using the UPPAAL model-checker. We model nodes by means of communicating timed automata, logical clocks and timing constraints. Through Computation Tree Logic we express and check properties for the election processes, related to energy and presence of greedy or jamming nodes.

Although substantial reductions in under-5 mortality have been observed during the past 35 years, progress in the Eastern Mediterranean Region (EMR) has been uneven. This paper provides an overview of child mortality and morbidity in the EMR based on the Global Burden of Disease (GBD) study. We used GBD 2015 study results to explore under-5 mortality and morbidity in EMR countries. In 2015, 755,844 (95% uncertainty interval (UI) 712,064-801,565) children under 5 died in the EMR. In the early neonatal category, deaths in the EMR decreased by 22.4%, compared to 42.4% globally. The rate of years of life lost per 100,000 population under 5 decreased 54.38% from 177,537 (173,812-181,463) in 1990 to 80,985 (76,308-85,876) in 2015; the rate of years lived with disability decreased by 0.57% in the EMR compared to 9.97% globally. Our findings call for accelerated action to decrease child morbidity and mortality in the EMR. Governments and organizations should coordinate efforts to address this burden. Political commitment is needed to ensure that child health receives the resources needed to end preventable deaths. ; Peer reviewed