Research On Intelligent Induction Technology Of Emergency Evacuation In Large Public Places

With the acceleration of urbanization in China,while the structure and function of large-scale public places are developing toward diversification and novelty,more and more attention is paid to the safety of large-scale crowd flow.However,due to the high density,large mobility and unfamiliar internal structure of personnel in large public places,the speed,effectiveness,reliability and intelligence of communication signal transmission of emergency evacuation indication system in large public places are being challenged to a certain extent.Based on the synergy of availability,crowding and evacuation capacity of evacuation passageway,as well as evacuation capability and retention phenomenon of the crowd,adaptive ant colony algorithm was used to set up the large-scale personnel emergency evacuation decision optimization model of large-scale public places,and the model was applied in some subway stations and commercial pedestrian street,and then was verified by Pathfinder software.The results show that the emergency evacuation decision optimization model constructed can achieve the global optimal optimization goal of evacuation route.While achieving the shortest overall actual evacuation time RSET,the model can balance the utilization rate of each exit to the greatest extent,and alleviate the phenomenon of crowd detention and congestion at some evacuation exits.In this paper,a parallel multithreading communication method is adopted to improve the intelligent emergency evacuation wireless guidance sign communication method based on LoRa,and the performance of communication signal transmission is tested in a subway station.The results show that the transmission between the central control end and intelligent wireless guidance emergency evacuation indicator signals can be completed within 0.2s,which meets the requirements of the response time for evacuation indicator sign in the Technical Standard for Fire Emergency Lighting and Evacuate Indicating System.The signal transmission time is irrelevant to the signal instruction contents.Transmission distance and the building structure have no impact on the signal transmission time.The operation of the metro vehicles in and out of the station and the electromagnetic signal of the electrical equipment have effects on signal transmission.The performance was tested the signs of the emergency evacuation wireless guidance in the environment of fire accident,the results show that can still be clearly identified in the environment with large smoke concentration,and can work normally in the environment with high thermal radiation and temperature.The demonstration application of the three-level linkage control system of fire monitoring front-end,central control end and intelligent emergency evacuation wireless guidance sign is carried out in a library.The results show that the system is able to apply the emergency evacuation decision optimization model to globally optimize evacuation path based on accident,and the visual and acoustic wireless guidance was realized.The system can guide personal to escape away from the point of ignition.The system can achieve wireless transmission,and has a flexible layout and signal transmission with high efficiency,etc.