迭代优化的网络最短路径射线追踪方法研究

网络最短路径射线追踪算法，用预先设置的网格节点的连线表示地震波传播路径，当网格节点稀疏时，获得的射线路径呈Z字形，计算的走时比实际走时偏差大.本文在网络最短路径射线追踪算法的基础上，提出了迭代法与网络最短路径相结合的射线追踪算法，运用迭代法优化计算由网络最短路径算法得到的射线路径，并对迭代法进行修正，从而克服了最短路径射线追踪算法的缺陷，大大提高了最小走时和射线路径的计算精度.

A method of shortest path raytracing by iterative optimization

The shortest path raytracing algorithm in networks is widely applied to calculate scismic ray paths and traveltimes, in which the beelines between network nodes are used to approximate the ray paths. When using a few nodes the ray usually follows a zig-zag path that is longer than the real raypath, and the calculated traveltime at a receiver is also larger than the real one. To solve this problem, we develop a shortest path raytracing by iterative optimization. We use the iterative algorithm to optimize ray path to overcome the weakness of the conventional networks algorithm, so the precision of calculated minimum traveltimes and the raypaths are improved greatly.