动态网络最短路径射线追踪算法中向后追踪方法的改进

An Improved Method on Backward Tracing of the Shortest Path Raytracing Algorithm with Dynamic Networks

动态网络最短路径射线追踪算法中的向后追踪方法能够解决线性走时插值算法(LTI)向后追踪过程不稳定的问题,但是其计算效率较低.综合利用节点次级源的位置信息以及波的传播规律,提出了改进方法,排除了动态网络最短路径射线追踪算法向后追踪过程中存在的大量冗余计算.数值算例表明,改进的向后追踪方法具有较高的计算效率,是动态网络最短路径射线追踪算法中向后追踪方法的几倍至几十倍;若将改进后的向后追踪方法应用于动态网络最短路径射线追踪改进算法,则该算法的计算效率将提高一倍左右.

The backward tracing method of the shortest path ray tracing algorithm with dynamic net- works can solve the unstability problem in the backward tracing procedure of the LTI （Linear Travel-time Interpolation） algorithm, but the computational efficiency of the method is low. This study presented an improved method on backward tracing. According to the location information of the secondary sources for the nodes and the law of wave propagation, a large number of redundancy calculation are excluded in the backward tracing of the dynamic networks tracing algorithm. The numerical examples show that the im- proved method exhibits the higher computational efficiency. The calculation efficiency of the improved method is several times that of the backward tracing method of the dynamic networks tracing algorithm. When the improved method is applied to the improved algorithm of the shortest path ray tracing with dy- namic networks, the computational efficiency of the algorithm can be increased by about 100 %.