He has developed what he describes as a percolation model for word puzzles. In his paper, Hartmann writes that he came to the idea of a percolation model for word puzzles while working on one himself.

Researchers develop a probabilistic framework using percolation theory to assess cascading cyber risks in drone swarms, enabling better insurance pricing and risk management for emerging drone ...

Mandsaur (Madhya Pradesh): In a significant event marking the 150th birth anniversary of Lord Birsa Munda, people's representatives performed bhoomi pujan for 58 new ponds and 212 percolation ...