基于BP网络的视电阻率快速计算  

Fast algorithm for apparent resistivity calculation based on back propagation neural networks

作　　者：谢品芳[1] 谢林涛[1] 付志红[1] 张淮清[1] 

机构地区：[1]重庆大学输配电装备及系统安全与新技术国家重点实验室,重庆400030

出　　处：《重庆大学学报（自然科学版）》2009年第9期1111-1116,共6页Journal of Chongqing University

基　　金：国家自然科学基金资助项目(40874094);三峡库区生态环境教育部重点实验室访问学者基金资助项目(KLVF-2007-1)

摘　　要：为避开复杂的电磁场数值计算,判断地下异常,用于现场指导,提出了神经网络的方法。讨论了实际发射机电流的非阶跃下降,并结合所用发射机对响应公式进行了关断延时校正。分析了常规的数值计算方法,由核函数的特点选用三层反向传播(back propagation,BP)网络结构,通过训练确定隐含层单元数和收敛较好的算法。用2种常规的数值算法与文中方法做仿真实验的对比,实验表明,用BP网络计算能快速实现瞬变电磁数据的处理,指导瞬变电磁探测。To avoid the complex numerical calculation for the electromagnetic field and determine underground abnormality, a neural network based method is proposed. In consideration of turn-off transmitter current, the effect of a linear ramp turn-off current on transmitter is corrected. The characteristics of transient expression and the traditional calculation algorithm for apparent resistivity are analyzed, and a predigest structure of network is obtained based on the kernel expression. The three-layer back propagation（BP） neural network is trained by using sample data in homogeneous half-space, and its number in hidden layer was determined. The method proposed is compared with two traditional calculation methods with simulation experiments. The result demonstrates that BP neural network has a high speed of processing data and is useful in explanation of the transient electromagnetic method.

关 键 词：瞬变电磁法 关断效应 BP网络 视电阻率 

分 类 号：TM153.1[电气工程—电工理论与新技术]