Research On Emergency Rescue Mobility Model And Emergency Communication System For Post-Earthquake

The frequent occurrence of earthquakes in China has brought serious threats to people’s lives and property.Earthquake observation and post-earthquake emergency rescue are important guarantees for reducing earthquake disaster losses.Firstly,the widely deployed communication equipment cluster for seismic observation undertakes the task of continuously updating and uploading the monitored seismic information.The status of the links in the cluster is of great important to data transmission.In this paper,an error ratio analysis method is proposed to define reasonable fault alarm threshold,which can provide accurate link status judgment basis for the cluster monitoring platform.Secondly,according to the catastrophic intensity,we propose a Four-quadrant Rescue Mobility Model which improves the rescue efficiency and reduces casualties.The post-earthquake rescue process is divided into two stages: opening way of saving lives stage and rescue spreading stage.In the first stage,we divide the whole disaster area into several regions according to the catastrophic intensities,and the rescuers move from outside to the severely affected area.In the second stage,we make further divisions according to the Four-quadrant Rescue Mobility Model,and rescuers are evenly allocated to each region.Simulation results show that the model can shorten the rescue time and reduce casualties under the conditions of equal disaster area numbers and equal catastrophic intensities.Furthermore,considering that the energy consumptions of mobile nodes are strictly limited in the disaster scenario,we design a multi criteria decision making method for the optimal next hop node selections.We establish a multi-criteria decision matrix based on four attributes: energy consumptions,numbers of connected nodes,hop counts to the emergency communication vehicle and distances to the emergency communication vehicle.The optimal next hop node is selected by solving the weighted multi-criteria decision matrix.Simulation results show that the energy consumptions are reduced and the packets reception rates are improved under this method.In the post-earthquake emergency communication network,the communication nodes have the characteristics of energy constraints,high communication energy consumptions and low data calculation energy consumptions.Locations of rescuers are frequently changing due to rescue tasks.In this paper,we design a new routing protocol based on the Four-quadrant Rescue Mobility Model as well as the optimal next hop node selection method.The new protocol modifies the format of routing request packet by adding four indexes: rescue urgency,quadrant level,quadrant partition set and quadrant weight.Simulation results show that the protocol improves the packets delivery rate and reduces the end-to-end delay in emergency communication network.After the devastating earthquake,the emergency communication network may be interfered by many wireless signals,and its bandwidth resources may be occupied either unintentionally or maliciously.According to four kinds of Unmanned Aerial Vehicles(UAVs)eavesdropping and jamming scenarios,as well as the constraints of UAV power limitations,we establish an optimization model for eavesdropping and jamming,which maximizes the number of eavesdropping packets.Furthermore,we propose the optimal selection algorithm for eavesdropping and jamming,and analyze the complexity of the algorithm theoretically.Simulation results show that the algorithm reduces the power consumption of eavesdropping and jamming,and increases the number of eavesdropped packets.In the end,we summarize the studies on emergency rescue mobility model and emergency communication system for post-earthquake,and then we point out the challenges and prospects in this field.