21 search results - page 4 / 5 » Characterization of eccentric digraphs |
ESA
1993
Springer
13 years 10 months ago
1993
Springer
A digraph is upward planar if it has a planar drawing such that all the edges are monotone with respect to the vertical direction. Testing upward planarity and constructing upward ...
MFCS
2007
Springer
13 years 12 months ago
2007
Springer
We show that every NP problem is polynomially equivalent to a simple combinatorial problem: the membership problem for a special class of digraphs. These classes are defined by me...
CLA
2004
13 years 7 months ago
2004
In Formal Concept Analysis, it is a very important but quite difficult task to draw line diagrams of concept lattices automatically. In particular, we want every planar lattice to ...
STOC
2003
ACM
14 years 6 months ago
2003
ACM
Let H be a fixed directed graph on h vertices, let G be a directed graph on n vertices and suppose that at least n2 edges have to be deleted from it to make it H-free. We show tha...
ENGL
2007
13 years 5 months ago
2007
Abstract—In any formal theory, a proof is a sequence of well formed formulas (wff). Here, we consider the digraph whose nodes are proofs and the edges are pairs of proofs such t...