The Research And Design Of A Real-time Monitoring System For Fire Safety

As the structure of buildings becomes more complex,electrified products become more common,the hidden dangers of fire safety accidents become increasingly prominent.Such accidents often cause serious loss of property,and people’s lives also cannot be guaranteed.With the gradual maturity of the Internet of Things system and the rapid development of essential technologies(sensor acquisition technology,wireless communication technology,Web technology etc.),it is possible to reduce the damage caused by fire safety accidents through collecting,processing and analyzing fire physical characteristics of the environment,then alarming and evacuating.It is aimed at the problems of narrow wireless communication coverage,weak signal penetration,insufficient anti-interference ability,and lack of data storage and processing and linkage with the fire department in traditional monitoring systems.This thesis designs and implements a real-time fire safety monitoring system combining with LoRa technology,one of Low Power Wide Area Network(LPWAN),and Web technology.The main contents and work done in this thesis include: First,according to the requirements of the system,the working mechanism of the system is expounded.Under this premise,the framework and design of the system were determined,and the design of each module were analyzed.Secondly,according to the physical quantities need to be monitored,three different sensors were selected,and the hardware of the acquisition module and the single-chip computer program were designed.In order to ensure the accuracy of data collection,the scanning cycle of data collection is optimized.Thirdly,in order to achieve the data transmission at the kilometer level and solve the problem of co-frequency interference and improve the expansibility of the system,combining the characteristics of LoRa technology,the networking mode of data transmission was determined and a timing polling solution was designed.Finally,on the Intelli J IDEA 2019 platform,with the use of Java and the WEB technology,a browser and appletbased data visualization and an application server was designed and implemented,to solve the problem of thread resource management of application server,a solution based on thread pool is designed.In this thesis,the designed system is functionally verified and tested.The verification results show that it can realize real-time monitoring,data visualization,real-time data refresh and software and hardware alarm functions;test results show that the average delay of data transmission is about 537 ms and the error rate is about 0%,The average delay of network requests is 461 ms,and the average communication distance is 2294 m.Each function and performance has reached the design index,which can meet certain actual monitoring needs.At the same time,the research on the fire safety monitoring system has certain reference significance.