This study used Topological Weighted Centroid (TWC) to analyze the Coronavirus outbreak in Brazil. This analysis only uses latitude and longitude in formation of the capitals with the confirmed cases on May 24, 2020 t...This study used Topological Weighted Centroid (TWC) to analyze the Coronavirus outbreak in Brazil. This analysis only uses latitude and longitude in formation of the capitals with the confirmed cases on May 24, 2020 to illustrate the usefulness of TWC though any date could have been used. There are three types of TWC analyses, each type having five associated algorithms that produce fifteen maps, TWC-Original, TWC-Frequency and TWC-Windowing. We focus on TWC-Original to illustrate our approach. The TWC method without using the transportation information predicts the network for COVID-19 outbreak that matches very well with the main radial transportation routes network in Brazil.展开更多
Many sensor network applications require location awareness,but it is often too expensive to equip a global positioning system(GPS) receiver for each network node.Hence,localization schemes for sensor networks typical...Many sensor network applications require location awareness,but it is often too expensive to equip a global positioning system(GPS) receiver for each network node.Hence,localization schemes for sensor networks typically use a small number of seed nodes that know their locations and protocols whereby other nodes estimate their locations from the messages they receive.For the inherent shortcomings of general particle filter(the sequential Monte Carlo method) this paper introduces particle swarm optimization and weighted centroid algorithm to optimize it.Based on improvement a distributed localization algorithm named WC-IPF(weighted centroid algorithm improved particle filter) has been proposed for localization.In this localization scheme the initial estimate position can be acquired by weighted centroid algorithm.Then the accurate position can be gotten via improved particle filter recursively.The extend simulation results show that the proposed algorithm is efficient for most condition.展开更多
针对传统DV-Hop无线传感器网络定位算法误差较大的缺点,将接收信号强度指示RSSI(received signal strength indicator)加入定位系统对原算法进行改进。通过RSSI测距技术计算信标节点邻居节点的距离;根据接收信号强度指示(RSSI)的比值修...针对传统DV-Hop无线传感器网络定位算法误差较大的缺点,将接收信号强度指示RSSI(received signal strength indicator)加入定位系统对原算法进行改进。通过RSSI测距技术计算信标节点邻居节点的距离;根据接收信号强度指示(RSSI)的比值修正节点间跳数;采用极大似然估计法对待定位节点坐标初步估计后再用加权质心算法进一步精确定位。仿真结果表明,该改进方法与传统DVHop算法相比定位精度有较大的提升。展开更多
文摘This study used Topological Weighted Centroid (TWC) to analyze the Coronavirus outbreak in Brazil. This analysis only uses latitude and longitude in formation of the capitals with the confirmed cases on May 24, 2020 to illustrate the usefulness of TWC though any date could have been used. There are three types of TWC analyses, each type having five associated algorithms that produce fifteen maps, TWC-Original, TWC-Frequency and TWC-Windowing. We focus on TWC-Original to illustrate our approach. The TWC method without using the transportation information predicts the network for COVID-19 outbreak that matches very well with the main radial transportation routes network in Brazil.
文摘Many sensor network applications require location awareness,but it is often too expensive to equip a global positioning system(GPS) receiver for each network node.Hence,localization schemes for sensor networks typically use a small number of seed nodes that know their locations and protocols whereby other nodes estimate their locations from the messages they receive.For the inherent shortcomings of general particle filter(the sequential Monte Carlo method) this paper introduces particle swarm optimization and weighted centroid algorithm to optimize it.Based on improvement a distributed localization algorithm named WC-IPF(weighted centroid algorithm improved particle filter) has been proposed for localization.In this localization scheme the initial estimate position can be acquired by weighted centroid algorithm.Then the accurate position can be gotten via improved particle filter recursively.The extend simulation results show that the proposed algorithm is efficient for most condition.
文摘针对传统DV-Hop无线传感器网络定位算法误差较大的缺点,将接收信号强度指示RSSI(received signal strength indicator)加入定位系统对原算法进行改进。通过RSSI测距技术计算信标节点邻居节点的距离;根据接收信号强度指示(RSSI)的比值修正节点间跳数;采用极大似然估计法对待定位节点坐标初步估计后再用加权质心算法进一步精确定位。仿真结果表明,该改进方法与传统DVHop算法相比定位精度有较大的提升。
