Fig. 1

Example of temporal subgraph isomorphism with \(\Delta =5\). Target T contains exactly one occurrence of query Q, which is the subgraph formed by nodes and edges colored in red. Subgraph \(S_1\) is not a solution because contacts do not all occur within time interval \(\Delta\). Subgraph \(S_2\) is not a solution because contacts do not follow the chronological order imposed by query edges, though all contacts occur within time interval \(\Delta\)