Quel systéme vocalique pour l 'enseignement du FLE?.

Sin resume

Design of a Lora-Based IoT Network using Enhance Clustering Protocols.

LoRa is an IoT (Internet of Things) enabling technology which is particularly suitable for low data rateapplications. The technology can achieve extended network coverage while operating in unlicensed ISM bandand falls into the category of Low Power Wide Area Networks (LPWANs) technologies. Currently, LoRa WANnetworks face challenges related to Collision rates, packet delivery, and efficient management of static andmobile nodes. Existing methods based on ALOHA have limitations that hinder the effectiveness inaccommodating the diverse requirements of Lora networks. In this study, A LoRa IOT network with bothstatic and mobile nodes is modelled in MATLAB Environment. Static-Based Time Slot (SBTS) and Energy-Aware Dynamic User Clustering (EADUC) clustering approaches are implemented for Clustering andimplemented using ALOHA and TDMA medium Access mechanisms. The implementation assesses how theseprotocols impact key network metrics like Signal-to-Interference Ratio (SIR), Packet Delivery Ratio (PDR) andCollision rate (CR). Result from the analysis underscores the clear performance superiority of the SBTS-TDMAprotocol in LoRa networks. SBTS-TDMA achieved the highest Signal-to-Interference Ratio (SIR) at 10.97 dB,significantly outperforming EADUC-TDMA, EADUC-ALOHA, and SBTS-ALOHA, which enhances interferencemanagement. It also excelled in Packet Delivery Ratio (PDR), reaching 78.84%, demonstrating greaterreliability in data transmission than other protocols. Additionally, with a Collision Rate of just 0.00045, SBTS-TDMA outperformed EADUC-TDMA, EADUC-ALOHA, and SBTS-ALOHA, reinforcing its efficiency andreliability for data integrity in LoRa networks

An Improved Energy-Aware Distributed Unequal Clustering Protocol using BBO Algorithm for Heterogeneous Load Balancing

With the rapid extension of IoT-based applications various distinct challenges are emerging in this area Among these concerns the node s energy efficiency has a special importance since it can directly affect the functionality of IoT-Based applications By considering data transmission as the most energy-consuming task in IoT networks clustering has been proposed to reduce the communication distance and ultimately overcome node energy wastage However cluster head selection as a non-deterministic polynomial-time hard problem will be challenging notably by considering node s heterogeneity and real-world IoT network constraints which usually have conflicts with each other Due to the existence of conflict among the main system parameters various solutions have been proposed in recent years that each of which only considered a few real-world limitations and parameter

Boletín oficial de la provincia de León: Num. 69 (08/06/1866)

Copia digital. Valladolid : Junta de Castilla y León. Consejería de Cultura y Turismo, 2011-201

A Review on Hierarchical Unequal Clustering Based Protocols in Wireless Sensor Network

Wireless Sensor Networks (WSNs) are drawing attention of various researchers in the area of wireless sensing technology. The one of the major constraint on WSNs is the limited battery resources. Due to this, the routing among sensor nodes plays a vital role in reducing the energy consumption of nodes. Clustering not only provides scalability to the network, but it also balances the energy consumption among nodes according to their roles in the cluster. Equal clustering creates the problem of Hot-Spot among those nodes that have to relay the data from the farther clusters. In this paper we have studied various routing protocols which follow unequal clustering. It is found after studying these protocols that unequal clustering help tremendously in saving the energy and avoids the problem of Hot-Spot

Secure and Energy Efficient Distributed Routing protocol using GA-BWO for Large Scale WSNs

Large scale wireless sensor network (LS-WSN)is one of the important parts in modern-daycommunication that employing low-cost sensor devices with different environmental and physicalparameters. The secure communication path between the base station and sensor nodes are built withthe help of an efficient routing protocol. In the past years, the existing protocols met few difficulties interms of higher computational complexity, poor cluster head selection performance, higher energyconsumption, lower security, expensive in cluster head selection, scalability management, and unevenload distribution, and so on.In this paper, Secure Energy-Efficient Distributed (SEED) protocol withmultiple sink nodes was developed to select the best residual energy. secure path selection usinggenetic algorithm mutation (GA)with black widow optimization (BWO) approach.The novel routingprotocol is named as GA-BWO-SEED. Particularly, the mutation phase of the conventional BWOalgorithm is improved with the help of direction average strategy of genetic algorithm. Further,thefuzzy logic system (FLC) selects the most relevant and optima cluster heads. The simulationresults shows that the proposed GA-BWO-SEED method demonstrates optimal performance outputamong all other methods

Campus Crier

Student newspaper for Central Washington University for April 27, 1939https://digitalcommons.cwu.edu/cwu_student_newspaper/1328/thumbnail.jp

A QoS-Aware Data Collection Protocol for LLNs in Fog-Enabled Internet of Things

© 2004-2012 IEEE. Improving quality of service (QoS) of low power and lossy networks (LLNs) in Internet of things (IoT) is a major challenge. Cluster-based routing technique is an effective approach to achieve this goal. This paper proposes a QoS-Aware clustering-based routing (QACR) mechanism for LLNs in Fog-enabled IoT which provides a clustering, a cluster head (CH) election, and a routing path selection technique. The clustering adopts the community detection algorithm that partitions the network into clusters with available nodes' connectivity. The CH election and relay node selection both are weighted by the rank of the nodes which take node's energy, received signal strength, link quality, and number of cluster members into consideration as the ranking metrics. The number of CHs in a cluster is adaptive and varied according to a cluster state to balance the energy consumption of nodes. Besides, the protocol uses the CH role handover technique during CH election that decreases the control messages for the periodic election and cluster formation in detail. An evaluation of the QACR has performed through simulations for various scenarios. The obtained results show that the QACR improves the QoS in terms of packet delivery ratio, latency, and network lifetime compared to the existing protocols

Scalability Analysis of the UDCOPA Protocol in Large and Massive IoT Environments

Clustering has a very positive impact on any optimization problem on the Internet of Things (IoT) or Wireless Sensor Networks (WSN). Energy efficiency based on clustering has proved its efficiency in this area of research, increasing the lifetime of the network and the high availability of services provided by applications based on this type of networks. Unequal clustering represents an advance on equal clustering in terms of flexibility, as it does not impose a predefined radius for clusters formation by elected CHs. Instead, CHs can dynamically adjust the size of their clusters or the radius of their condidature or election according to various factors and criteria, such as energy constraint. As a result, this type of clustering optimizes energy consumption, balances the load between CHs and improves scalability. Unequal-DCOPA (UDCOPA) is an unequal clustering protocol, which enhances the DCOPA protocol (A Distributed Clustering Based on Objects Performances Aggregation for Hierarchical Communications in IoT Applications), that allows CHs to optimize their energy and send a message announcing their solicitation over an Adaptive Radius of Clustering (ARC) that is adjusted according to its local parameters. In this paper, we explore the geographical and quantitative scalability of this protocol as well as the load balancing of clusters and CHs. The results show that UDCOPA is a scalable protocol that maintains its energy and lifetime properties even in geographically very large areas and in massive environments