Based on Image Theory and tube-tree method, an applicable ray tracing method based on virtual source tree was presented in this paper.

本文在参照了镜像法、射线管法等射线跟踪思想的基础上，提出了一种有效的基于虚拟源树的射线跟踪模型。

youdao

This paper provides an effective ray tracing method for prediction of microcellular radio propagation, which is called a ray tracing method based on virtual source binary tree.

本文提出了一种能有效预测微小区环境中电波传播的射线跟踪算法——基于虚拟源二叉树的射线跟踪算法。

youdao

But each resource - a file or folder - in this source tree can have complicated version graphs, based on the branches created for each resource. (so in this sense a VOB is like a virtual repository).

但是每一个资源，一个文件或是一个文件夹，在这棵资源树中都对应于很复杂的版本图，这些版本图是基于对每个资源所创建的分支。(这么看起来，VOB像一个虚拟库。)

youdao