Improving placement of CSA-nets

Communication structured acyclic nets (CSA-nets) are a Petri net-based formalism for representing interactions between subsystems of complex evolving systems (CES). CSA-nets, made up of sets of acyclic-nets, are suitable tools for modelling and visualising event-based systems' execution behaviour. Each subsystem is represented using a separate acyclic net and is linked with other acyclic nets through a set of buffer places. These buffer places link different acyclic nets and depict their interactions. Analysis and visualising CES is a complex task. The hurdle is that a huge number of subsystems resulting from alternative and concurrent scenarios of CESs results in a huge number of buffer places, increasing the number of crossings arcs. One way to mitigate this problem is to filter out some system components. However, this results in information loss. This paper focuses on improving the visualisation of CSA-nets by rearranging their component acyclic nets to minimise the number of crossing arcs. To this end, this paper takes inspiration from the main ideas behind three well-known sorting algorithms, viz. bubble sort, insertion sort and selection sort, and integrates them with formulas to compute crossing. Experimental comparisons are carried out to compare the improvements resulting from following each of the three approaches. The outcomes point to the high effectiveness of the selection sort-inspired approach.