选取四川阿坝州九寨沟县M_S7.0地震、新疆博尔塔拉州精河县M_S6.6地震、四川广元市青川县M_S5.4地震作为案例分析，绘制活跃WiFi数量、无线网络联网设备数量、汇总在线设备数量、活跃基站数量等4种地震灾情指标在地震发生前后数量变化的折线图。根据与地震前1天变化情况的对比分析，验证地震灾情指标的可用性，选取出效果好的指标，这对进一步研究震后快速获取极震区位置、影响场方向等具有重要意义。

Four earthquakes with M_S7.0 in Jiuzhaigou, Sichuan, M_S6.6 in Jinghe County, Boltara Prefecture, Xinjiang, M_S5.4 in Qingchuan County, Guangyuan City, Sichuan, and M_S4.8 in Rongchang District, Chongqing, were selected as case studies. We draw the line charts of the four earthquake disaster indices(the number of active WiFi, the number of wireless network networking equipment, the number of online equipment, the number of active stations) before and after the occurrence of earthquake to show their changes in number. the availability of earthquake disaster index is verified by comparing it with that of the previous day, and the effective index is selected, which is convenient for further research on the rapid acquisition of the location of the extreme earthquake area and the direction of the influence field after the earthquake.

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国家重点研发计划项目（2018YFC1504503、2018YFC1504403）、“大中城市地震灾害情景构建”重点专项（2016QJGJ14）共同资助