Tracking and Visualizing RFID-driven Material Flows for Multistage Machining Processes

A performance evaluation method for radio frequency identification–based tracking network of job-shop-type work-in-process material flows

“…In order to describe and formulate a material flow in job shops visually, an ''event-driven'' graphical schema model is proposed in the authors' early articles. 3,28 Table 1 shows the important concepts of the operations/ actions, triggering times, positions, and workpiece states in this schema model. As illustrated in Figure 1, there are four steps to describe the WIP material flows using the event-driven graphical schema.…”

“…The tracking particle size for machining or inventory process p i is written as a i . From the literature, 3,28 we can get that the RFID-based detecting spaces are used to monitor the workpiece states. Therefore, the number of workpiece states during a process is corresponding with the number of RFIDbased detecting spaces, and this parameter can be used to describe the tracking intensity of the process…”