Construction of Non-expandable Non-overlapping Sets of Pictures
  The non-overlapping sets of pictures are sets such that no two pictures in the set (properly) overlap. They are the generalization to two dimensions of the cross-bifix-free sets of strings. Non-overlapping sets of pictures are non-expandable when no other picture can be added without violating the property. We present a construction of non-expandable non-overlapping (NENO) sets of pictures and show some examples of application. 
Marcella Anselmo, Dora Giammarresi, Maria Madonia
cs.FL