For digraphs D and H, a mapping f : V (D)V (H) is a homomorphism of D to H if uv A(D) implies f(u)f(v) A(H). If, moreover, each vertex u V (D) is associated with costs ci(u), i...
Mader asked whether every C4-free graph G contains a subdivision of a complete graph whose order is at least linear in the average degree of G. We show that there is a subdivision...
Let P be a set of points in Rd . We propose GEOFILTERKRUSKAL, an algorithm that computes the minimum spanning tree of P using well separated pair decomposition in combination with ...
Given a spatio-temporal network (ST network) whose edge properties vary with time, a time-sub-interval minimum spanning tree (TSMST) is a collection of distinct minimum spanning t...
The phenomenon of visual curve completion, where the visual system completes the missing part (e.g., due to occlusion) between two contour fragments, is a major problem in percept...