Efficient Semantics-Based Compliance Checking Using LTL Formulae and Unfolding

Algorithm 9

Determining the basic predicate concur.

function  CONCUR

Input: Two taskID 𝑡 and 𝑡^′, a process model 𝑟

Output: A boolean value

begin

 𝔾∶=  RetrieveBigraphs(𝑟);

 return _𝐺⋀_∈𝔾((RetrieveAllEvents(𝐺,𝑡)=∅∧  RetrieveAllEvents(𝐺,𝑡^′)=∅)∨

     (RetrieveAllEvents(𝐺,𝑡)≠∅∧  RetrieveAllEvents(𝐺,𝑡^′)≠∅∧

     ∀_{𝑒∈𝖱𝖾𝗍𝗋𝗂𝖾𝗏𝖾𝖠𝗅𝗅𝖤𝗏𝖾𝗇𝗍𝗌(𝐺,𝑡)}∀_{𝑒′∈𝖱𝖾𝗍𝗋𝗂𝖾𝗏𝖾𝖠𝗅𝗅𝖤𝗏𝖾𝗇𝗍𝗌(𝐺,𝑡′)}[NoDirectedPath(𝑒,𝑒^′,𝐺)∧  NoDirectedPath(𝑒^′,𝑒,𝐺)]))