Topology is the top-most element of any topology model. 拓扑是任何拓扑模型的最高层元素。
Output scope of the conditional transformation group is defined as being between the top-most connected output element and the bottom-most connected output element. 条件转换组合的输出范围被定义为介于最顶级的连接输出元素和最底层的连接输出元素之间。