摘要
基于美国大学大气联盟发布的电离层F2层最大电子密度数据NmF2,以年积日DOY、当地时LT、经度LON、纬度LAT和F10.7太阳活动指数FLUX为输入,利用MATLAB神经网络工具箱构建区域电离层模型并进行模拟,通过模型值与观测值的比较发现,2012年4月11日印尼8.6级地震前震中附近上空NmF2在震前第16天(3月26日)明显减小约40%。
On the basis of the F2 layer peak electron density(NmF2) from University Corporation for Atmospheric Research(UCAR),U.S.A.,we constructed a Back Propogation(BP) artificial neural network(ANN) into which inputting five parameters:DOY(day of year),local time(LT),longitude(LON),latitude(LAT) and solar activity index of F10.7(FLUX) and then using the Matlab ANN for building the local ionosphere model and made the simulation.Through comparing the model value with observations during the 2012 Indonesia earthquake period,it is found that around the epicenter a obvious NmF2 decrease appeared on day 16(26 March) before the earthquake,the rate of decline to 40%.
引文
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