Identifying Data-Flow Errors in Cyber-Physical Systems Based on the Simplified Merged Process of Petri Nets

Data-flow errors are prevalent in cyber-physical systems (CPS). Although various approaches based on business process modeling notation (BPMN) have been devised for CPS modeling, the absence of formal specifications complicates the verification of data-flow. Formal techniques such as Petri nets are popularly used for identifying data-flow errors. However, due to their interleaving semantics, they suffer from the state-space explosion problem. As an unfolding method for Petri nets, the merged process (MP) technique can well represent concurrency relationships and thus be used to address this issue. Yet generating MP is complex and incurs substantial overhead. By designing and applying <tex>$\alpha$</tex>-deletion rules for Petri nets with data (PNDs), this work simplifies MP, thus resulting in simplified MP (SMP) that is then used to identify data-flow errors. Our approach involves converting a BPMN into a PND and then constructing its SMP. The algorithms are developed to identify data-flow errors, e.g., redundant-data and lost-data ones. The proposed method enhances the efficiency and effectiveness of identifying data-flow errors in CPS. It is expected to prevent the problems caused by data-flow errors, e.g., medical malpractice and economic loss in some practical CPS. Its practicality and efficiency of the proposed method through several CPS. Its significant advantages over the state of the art are demonstrated.