The definition of hinge is as follows. Let formula_6 be a set of hyperedges. A path w.r.t. formula_6 is a sequence of edges such that the intersection of each one with the next one is non-empty and not contained in the nodes of formula_6. A set of edges is connected w.r.t. formula_6 if, for each pair of its edges, there is a path w.r.t. formula_6 of which the two nodes are the first and the last edge. A connected component w.r.t. formula_6 is a maximal set of connected edges w.r.t. formula_6.