Construction and use of national emergency broadcast system, related to the safety of lives and property. Broadcasting system has the simple construction, easy to set up, transmission distance, wide transmission range...Construction and use of national emergency broadcast system, related to the safety of lives and property. Broadcasting system has the simple construction, easy to set up, transmission distance, wide transmission range, transmission speed, etc., in the notice of emergency incidents, emergency command, emergency evacuation and emergency settle played a pivotal role. In the recent years, countries earthquakes, tsunamis and other natural disasters occur frequently, causing great loss of life and property, the establishment of the emergency broadcast system, more and more government attention. We introduced the emergency broadcast system in Japan, the United States, Britain and other countries, analyzes the problems our country to carry out emergency broadcast services need to pay attention, and made recommendations.展开更多
Vehicular ad-hoc networks(VANETs)play an essential role in enhancing transport infrastructure by making vehicles intelligent and proficient in preventing traffic fatalities.Direction-based greedy protocols pick the ne...Vehicular ad-hoc networks(VANETs)play an essential role in enhancing transport infrastructure by making vehicles intelligent and proficient in preventing traffic fatalities.Direction-based greedy protocols pick the next route vehicle for transmitting emergency messages(EMs)depending upon the present location of adjacent vehicles towards sink vehicles by using an optimal uni-directional road traffic approach.Nevertheless,such protocols suffer performance degradation by ignoring the moving directions of vehicles in bi-directional road traffic where topological changes happen continuously.Due to the high number of vehicles,it is essential to broadcast EMs to all vehicles to prevent traffic delays and collisions.A cluster-based EM transmitting technique is proposed in this paper.For urban VANETs,this paper pioneers the clustering of bi-directional road traffic for robust and efficient routing of EMs.In this regard,this paper introduces a routing protocol,namely,the bi-directional urban routing protocol(BURP).In addition to the paths and relative locations of vehicles,BURP takes account of the distance parameter by using the Hamming distance function to determine the direction ofmotion of vehicles and communicates EMs through the cluster head(CH).Amodified k-medoids algorithm is presented for the clustering of bi-directional road traffic.A median method is presented for selecting CH to ensure the longrunning of a cluster.Simulation results show that BURP provides enhanced throughput,a maximized packet delivery ratio,low energy consumption,and network delay relative to eminent routing protocols.展开更多
5G新无线空口组播广播服务(5G-New Radio Multicast and Broadcast Services,5G NR MBS)技术可以显著提高广播电视信号的传播距离和覆盖范围,极大拓宽应急广播的传播路径和信息容量,进而有效满足应急广播关键任务的实际需求。深入研究5...5G新无线空口组播广播服务(5G-New Radio Multicast and Broadcast Services,5G NR MBS)技术可以显著提高广播电视信号的传播距离和覆盖范围,极大拓宽应急广播的传播路径和信息容量,进而有效满足应急广播关键任务的实际需求。深入研究5G广播技术+应急广播系统的融合模式,进一步阐述5G NR MBS技术应用于应急广播关键任务的组织架构、实施方法与步骤以及应用场景等具体内容。实践表明,5G NR MBS技术能够在应急广播信号广域覆盖和定向传输等方面提供稳定的技术支撑,弥补了信号弱覆盖方面的不足,解决了应急广播“最后一公里”覆盖面不全、方向不精准等现实问题。展开更多
文摘Construction and use of national emergency broadcast system, related to the safety of lives and property. Broadcasting system has the simple construction, easy to set up, transmission distance, wide transmission range, transmission speed, etc., in the notice of emergency incidents, emergency command, emergency evacuation and emergency settle played a pivotal role. In the recent years, countries earthquakes, tsunamis and other natural disasters occur frequently, causing great loss of life and property, the establishment of the emergency broadcast system, more and more government attention. We introduced the emergency broadcast system in Japan, the United States, Britain and other countries, analyzes the problems our country to carry out emergency broadcast services need to pay attention, and made recommendations.
文摘Vehicular ad-hoc networks(VANETs)play an essential role in enhancing transport infrastructure by making vehicles intelligent and proficient in preventing traffic fatalities.Direction-based greedy protocols pick the next route vehicle for transmitting emergency messages(EMs)depending upon the present location of adjacent vehicles towards sink vehicles by using an optimal uni-directional road traffic approach.Nevertheless,such protocols suffer performance degradation by ignoring the moving directions of vehicles in bi-directional road traffic where topological changes happen continuously.Due to the high number of vehicles,it is essential to broadcast EMs to all vehicles to prevent traffic delays and collisions.A cluster-based EM transmitting technique is proposed in this paper.For urban VANETs,this paper pioneers the clustering of bi-directional road traffic for robust and efficient routing of EMs.In this regard,this paper introduces a routing protocol,namely,the bi-directional urban routing protocol(BURP).In addition to the paths and relative locations of vehicles,BURP takes account of the distance parameter by using the Hamming distance function to determine the direction ofmotion of vehicles and communicates EMs through the cluster head(CH).Amodified k-medoids algorithm is presented for the clustering of bi-directional road traffic.A median method is presented for selecting CH to ensure the longrunning of a cluster.Simulation results show that BURP provides enhanced throughput,a maximized packet delivery ratio,low energy consumption,and network delay relative to eminent routing protocols.
文摘5G新无线空口组播广播服务(5G-New Radio Multicast and Broadcast Services,5G NR MBS)技术可以显著提高广播电视信号的传播距离和覆盖范围,极大拓宽应急广播的传播路径和信息容量,进而有效满足应急广播关键任务的实际需求。深入研究5G广播技术+应急广播系统的融合模式,进一步阐述5G NR MBS技术应用于应急广播关键任务的组织架构、实施方法与步骤以及应用场景等具体内容。实践表明,5G NR MBS技术能够在应急广播信号广域覆盖和定向传输等方面提供稳定的技术支撑,弥补了信号弱覆盖方面的不足,解决了应急广播“最后一公里”覆盖面不全、方向不精准等现实问题。
