Using extended activity-network diagram to design a process quality control model

A complicated mechanical product to be manufactured always contains a series of procedures named processes or operations which form a complicated network diagram. In order to guarantee the process quality and the final quality of product, this paper presents a process quality control model by using the extended activity-network diagram technique. In this control model, task nodes correspond to processes or operations and arcs to relationship between two nodes. The functions of a task node are made up of event and status. The event refers to the activities of off-line or on-line quality control and fault diagnosis of a process or an operation while status to error status and its transmitting rule of a process or an operation. The proposed model can map and navigate the quality control procedure of multistage processes well.