双代号收集图绘制中的虚箭线剖断(国外英文资料).doc

双代号网络图绘制中的虚箭线判定(国外英文资料) The virtual arrow line in the double codename network graph is determined by the existence, pointing and number In the drawing of the double codename network diagram, it is often necessary to introduce virtual arrows. But the accurate decision of the virtual arrows is more complicated than the correct drawing. , based on the application of virtual arrow line are summarized on the basis of, respectively, are given by the mapping relationship between requirement and need to introduce and required by the logical relations should be introduced, pointing to the existence of dummy arrow line and the number of criteria. The application of virtual arrows is applied The application of the virtual arrow line in the double codename network diagram can be summarized from the requirements of network logic relation and drawing relation. As shown in figure 1: The virtual arrow line required by the drawing relationship 2.1 drawing relationship requirements Drawing relationship requirement refers to the requirement that a pair of codename can represent only one job during the drawing process of the double codename network diagram. That is to say, there is no such thing as multiple work items in the drawing of the double code network diagram. Can be a number of job sharing a start node (called the node branch node) or sharing a complete node (called a collection for the node), but cant work many share the same start and finish on a node. The virtual arrows line of the drawing relationship is determined Compared with the virtual arrows, which are required by logical relations, the judgment (existence, pointing, and number) of the virtual arrows required by the drawing relationship is simple. Summarized as follows: The criterion of virtual arrows for drawing relationships -- Existence verdict: when n (n = 2) work begins and at the same time, there is a virtual arrow line, i.e. the need to introduce virtual arrows. Pointing to the decision: the virtual arrow lin