Guess-and-determine attack is one of the general attacks on stream ciphers. It is a common cryptanalysis tool for evaluating security of stream ciphers. The effectiveness of this attack is based on the number of unknown bits which will be guessed by the attacker to break the cryptosystem. In this work, we present a relation between the minimum numbers of the guessed bits and uniquely restricted...

This paper considers some classes of graphs which are easily seen to have many perfect matchings. Such graphs can be considered robust with respect to the property of having a perfect matching if under vertex deletions (with some mild restrictions), the resulting subgraph continues to have a perfect matching. It is clear that you can destroy the property of having a perfect matching by deleting...

A graph G is 1-extendable or almost 1-extendable if every edge is contained in a perfect or almost perfect matching of G, respectively. Let d ≥ 3 be an integer, and let G be a graph of order n with exactly one odd component such that the degree of each vertex is either d or d + 1. If G is not almost 1-extendable, then we prove that n ≥ 2d + 5. In the special case that d ≥ 4 is even and G is a d...

The dimer model is a statistical mechanical model on a graph, where configurations consist of perfect matchings of the vertices. For planar graphs, expressions for the partition function and local statistics can be obtained using determinants. The planar dimer model can be used to model a number of other statistical mechanical processes such as the planar Ising model and free fermions. It is al...

In this paper we investigate the question whether a perfect matching can be isolated by a weighting scheme using Chinese Remainder Theorem (short: CRT). We give a systematical analysis to a method based on CRT suggested by Agrawal in a CCC’03-paper for testing perfect matchings. We show that this desired test-procedure is based on a deterministic weighting scheme which can be generalized in a n...

Let γ(G) be the domination number of a graph G. A graph G is domination-vertex-critical, or γ-vertex-critical, if γ(G− v) < γ(G) for every vertex v ∈ V (G). In this paper, we show that: Let G be a γ-vertex-critical graph and γ(G) = 3. (1) If G is of even order and K1,6-free, then G has a perfect matching; (2) If G is of odd order and K1,7-free, then G has a near perfect matching with only three...

Let γ(G) be the domination number of a graphG. A graphG is dominationvertex-critical, or γ-vertex-critical, if γ(G − v) < γ(G) for every vertex v ∈ V(G). In this paper, we show that: Let G be a γ-vertex-critical graph and γ(G) = 3. (1) If G is of even order and K1,6-free, then G has a perfect matching; (2) If G is of odd order and K1,7-free, then G has a near perfect matching with only three ex...