摘要: Data Flow Diagram(DFD)has been widely used in Software Engineering as means of require- ment analysis and system specification.However,one defect of DFD approach remains untackled: the lack of formal semantics has brought about a lot of problems.In this paper,we model Data Flow Diagram as networks of concurrent processes.With the use of temporal logic language XYZ/E,the formal basis of the semantic specification of DFD can be ensured,and the system prop- erties sach as safety and liveness can be easily char…