Extend motif analysis to longer subsequences

Extend the network-motif analysis of near-wall turbulence from three-node octant subsequences to four-node subsequences in order to identify longer dynamical patterns involving sequences of more than three octants.

Background

The study identifies statistically significant motifs consisting of three successive octants in the state space of roll-like, streak, and meander mode energies. Overlapping three-node motifs in the MFU180 and FB180 suggest longer patterns involving four or more successive octants.

The authors do not perform the four-node analysis because it would require substantially more data, but explicitly leave this extension unresolved for future work.

References

Extending this analysis to sub-sequences of length four would likely reveal further insights into these longer patterns, though this would require substantially more data and is left for future work.

— Coherent-structure dynamics in wall turbulence from state-space trajectories  (2609.04515 - Lenz et al., 3 Sep 2026) in Section 3.1.2, subsection “$(r,s,m)$ network motifs”