Location Embedding and Deep Convolutional Neural Networks for Next Location Prediction

International audienc

QCOF: New RPL Extension for QoS and Congestion-Aware in Low Power and Lossy Network

Low power and lossy networks (LLNs) require a routing protocol under real-time and energy constraints, congestion aware and packet priority. Thus, Routing Protocol for Low power and lossy network (RPL) is recommended by Internet Engineering Task force (IETF) for LLN applications. In RPL, nodes select their optimal paths towards their preferred parents after meeting routing metrics that are injected in the objective function (OF). However, RPL did not impose any routing metric and left it open for implementation. In this paper, we propose a new RPL objective function which is based on the quality of service (QoS) and congestion-aware. In the case paths fail, we define new RPL control messages for enriching the network by adding more routing nodes. Extensive simulations show that QCOF achieves significant improvement in comparison with the existing objective functions, and appropriately satisfies real-time applications under QoS and network congestion.info:eu-repo/semantics/publishedVersio

Joint Connectivity-Coverage Temperature-Aware Algorithms for Wireless Sensor Networks

International audienceTemperature variations have a significant effect on low power wireless sensor networks as wireless communication links drastically deteriorate when temperature increases. A reliable deployment should take temperature into account to avoid network connectivity problems resulting from poor wireless links when temperature increases. A good deployment needs also to adapt its operation and save resources when temperature decreases and wireless links improve. Taking into account the probabilistic nature of the wireless communication channel, we develop a mathematical model that provides the most energy efficient deployment in function of temperature without compromising the correct operation of the network by preserving both connectivity and coverage. We use our model to design three temperature-aware algorithms that seek to save energy (i) by putting some nodes in hibernate mode as in the SO (Stop-Operate) algorithm, or (ii) by using transmission power control as in PC (Power-Control), or (iii) by doing both techniques as in SOPC (Stop-Operate Power-Control). All proposed algorithms are fully distributed and solely rely on temperature readings without any information exchange between neighbors, which makes them low overhead and robust. Our results identify the optimal operation of each algorithm and show that a significant amount of energy can be saved by taking temperature into account

Location Embedding and Deep Convolutional Neural Networks for Next Location Prediction

International audienc

Allongement de la durée de vie des réseaux sans fils de capteurs par l'optimisation des protocoles de routage et d'accès au canal

L'allongement de la durée de vie d'un réseau de capteurs requiert des optimisations sur deux niveaux complémentaires: local et global. Sur le niveau local, chaque nœud doit optimiser sa consommation d'énergie pour allonger sa durée de vie, et sur le niveau global, les nœuds doivent coopérer ensemble pour optimiser la gestion globale des ressources en énergie. Dans cette thèse nous nous sommes attaqués à ces deux problèmes par l'optimisation des protocoles de communications. Notre contribution a principalement touché les protocoles MAC et de routage. Au niveau de la couche MAC, nous avons travaillé sur la réduction de deux principales sources de perte d'énergie: les collisions et l'écoute inutile. Nous avons différencié deux types de collisions: celles causées par les nœuds cachés et celles causées par les nœuds visibles, et deux formes d'écoute inutile: celle résultant de la réception des messages inutiles et celle provenant de la réception des signaux inutiles. Pour toutes ces formes de perte d'énergie, nous avons proposés des solutions pertinentes. Au niveau de la couche routage, nous avons proposé un protocole permettant de combiner deux techniques d'allongement de durée de vie du réseau: la réduction du surcoût des protocoles et l'équilibrage de charge entre les nœuds pour leur éviter une mort prématurée. Notre contribution dans cette thèse non seulement fournit des protocoles MAC et des protocoles de routage efficaces en énergie et optimisés les uns indépendamment des autres, mais aussi une ébauche de conception inter couches dans laquelle les protocoles sont optimisés conjointement.Extending the lifetime of a sensor network requires optimizations at two complementary scopes: local and global. At the scope front, each node should optimize its own energy consumption to maximize its life span. At the global scope, nodes should cooperate to optimize the global usage of energy resources. ln this thesis, we have addressed both problems through the optimization of communication protocols. Our contribution mainly concerns MAC and Routing protocols. At the MAC layer, we have tackled the problem of reduction two major sources of energy waste: collisions and overhearing. We have differentiated two types of collisions: those caused by hidden nodes and those caused by visible nodes, and two forms of overhearing: that resulting from the reception of irrelevant messages and that resulting from the reception of useless signais. For ail of these identified sources of energy waste, we have proposed solutions that improve the networks lifetime. At the routing layer, we have proposed a protocol capable of combining two lifetime extension techniques: reducing protocols' overhead and load balancing among nodes to avoid their premature death Our contribution in this thesis not only provides more energy-efficient MAC and routing protocols that are optimized independently from each other, but also a cross layer design in which MAC and routing protocols are jointly optimized.GRENOBLE1-BU Sciences (384212103) / SudocSudocFranceF

Allongement de la durée de vie des réseaux sans fils de capteurs par l'optimisation des protocoles de routage et d'accès au canal

L'allongement de la durée de vie d'un réseau de capteurs requiert des optimisations sur deux niveaux complémentaires: local et global. Sur le niveau local, chaque nœud doit optimiser sa consommation d'énergie pour allonger sa durée de vie, et sur le niveau global, les nœuds doivent coopérer ensemble pour optimiser la gestion globale des ressources en énergie. Dans cette thèse nous nous sommes attaqués à ces deux problèmes par l'optimisation des protocoles de communications. Notre contribution a principalement touché les protocoles MAC et de routage. Au niveau de la couche MAC, nous avons travaillé sur la réduction de deux principales sources de perte d'énergie: les collisions et l'écoute inutile. Nous avons différencié deux types de collisions: celles causées par les nœuds cachés et celles causées par les nœuds visibles, et deux formes d'écoute inutile: celle résultant de la réception des messages inutiles et celle provenant de la réception des signaux inutiles. Pour toutes ces formes de perte d'énergie, nous avons proposés des solutions pertinentes. Au niveau de la couche routage, nous avons proposé un protocole permettant de combiner deux techniques d'allongement de durée de vie du réseau: la réduction du surcoût des protocoles et l'équilibrage de charge entre les nœuds pour leur éviter une mort prématurée. Notre contribution dans cette thèse non seulement fournit des protocoles MAC et des protocoles de routage efficaces en énergie et optimisés les uns indépendamment des autres, mais aussi une ébauche de conception inter couches dans laquelle les protocoles sont optimisés conjointement.Extending the lifetime of a sensor network requires optimizations at two complementary scopes: local and global. At the scope front, each node should optimize its own energy consumption to maximize its life span. At the global scope, nodes should cooperate to optimize the global usage of energy resources. ln this thesis, we have addressed both problems through the optimization of communication protocols. Our contribution mainly concerns MAC and Routing protocols. At the MAC layer, we have tackled the problem of reduction two major sources of energy waste: collisions and overhearing. We have differentiated two types of collisions: those caused by hidden nodes and those caused by visible nodes, and two forms of overhearing: that resulting from the reception of irrelevant messages and that resulting from the reception of useless signais. For ail of these identified sources of energy waste, we have proposed solutions that improve the networks lifetime. At the routing layer, we have proposed a protocol capable of combining two lifetime extension techniques: reducing protocols' overhead and load balancing among nodes to avoid their premature death Our contribution in this thesis not only provides more energy-efficient MAC and routing protocols that are optimized independently from each other, but also a cross layer design in which MAC and routing protocols are jointly optimized.GRENOBLE1-BU Sciences (384212103) / SudocSudocFranceF

Evaluating Regression Models for Temporal Prediction of Wi-Fi Device Mobility

International audienceThe ability to predict the arrival and residence time of mobile users at a particular place is essential for the development of a wealth of new applications and services, such as smart heating control, transportation planning or urban navigation. Previous techniques based on probabilistic models have not been able to perform such prediction accurately. In this paper, we present two linear mobility models, namely Linear Regression, and Auto-Regression, to predict the temporal behavior, particularly the residence time, of individual users. We run performance evaluation experiments on two different WiFi mobility traces datasets made available through the CRAWDAD project. Our results show that using linear regression-based learning algorithms significantly improve the residence time prediction accuracy compared to state-of-the-art methods, and achieve prediction errors in the order of seconds and minutes for a large number of users

Preamble sampling MAC protocols with persistent receivers in wireless sensor networks

very selective A+International audienceWe provide an analytical framework for preamble sampling techniques for MAC protocols in wireless sensor networks, from which we derive closed-form formulas for lifetime and reliability calculations. In addition to take into account transmitter behavior that controls the form and the content of the transmitted preamble, our model also considers receiver behavior that controls the duration of preamble reception in case of successful and failed reception. Along with both transmitter and receiver behavior, our model considers a non-perfect channel and thus takes into account the impacts of transmission errors and retransmissions on lifetime and reliability of preamble sampling protocols. Numerical results show that no protocol is universally optimal; that is, each protocol has its own optimal operation point that depends on the given channel and load conditions