a r t i c l e i n f o a b s t r a c t A graph Γ is k-CS-transitive, for a positive integer k, if for any two connected isomorphic induced subgraphs A and B of Γ , each of size k, there is an automorphism of Γ taking A to B. The graph is called k-CS-homogeneous if any isomorphism between two connected induced subgraphs of size k extends to an automor-phism. We consider locally-finite infinite k-...

a recursive-circulant $g(n; d)$ is defined to be acirculant graph with $n$ vertices and jumps of powers of $d$.$g(n; d)$ is vertex-transitive, and has some strong hamiltonianproperties. $g(n; d)$ has a recursive structure when $n = cd^m$,$1 leq c < d $ [10]. in this paper, we will find the automorphismgroup of some classes of recursive-circulant graphs. in particular, wewill find that the autom...

A regular and edge transitive graph which is not vertex transitive is said to be semisymmetric Every semisymmetric graph is necessarily bipartite with the two parts having equal size and the automorphism group acting transitively on each of these two parts A semisymmet ric graph is called biprimitive if its automorphism group acts prim itively on each part In this paper a classi cation of bipri...

In the past, diierent authors developed distinct approaches to the problem of transitive orientation. This also resulted in diierent ideas and diierent theorems which seem unrelated. In this paper we show the connections between these theories and present a new algorithm to recognize a comparability graph. A comparability graph is an undirected graph G = (V; E), jV j = n, jEj = m, in which ever...

Let Γ be a graph and let G be a group of automorphisms of Γ. The graph Γ is called G-normal if G is normal in the automorphism group of Γ. Let T be a finite non-abelian simple group and let G = T l with l ≥ 1. In this paper we prove that if every connected pentavalent symmetric T -vertex-transitive graph is T -normal, then every connected pentavalent symmetric G-vertex-transitive graph is G-nor...

An automorphism of a 7nite simple graph is an adjacency automorphism if for every vertex x∈V ( ), either x = x or x is adjacent to x in . An adjacency automorphism 7xing no vertices is a shift. A connected graph is strongly adjacency-transitive (respectively, uniquely shift-transitive) if there is, for every pair of adjacent vertices x; y∈V ( ), an adjacency automorphism (respectively, a unique...

A transitive signature scheme allows a signer to publish a graph in an authenticated and cost-saving manner. The resulting authenticated graph is indeed the transitive closure of the graph constructed by edges which are explicitly signed by the signer. A property of the transitive signature scheme enables such scenario is called composability which means that by knowing signatures on two edges ...

Summary: Associations among biological objects such as genes, proteins, and drugs can be discovered automatically from scientific literature. This paper describes ‘TransMiner’ a system for finding interesting associations among objects by mining the Medline database of scientific literature. The direct associations among the objects are discovered based on the principle of cooccurrence from the...

A near-polygonal graph is a graph Γ which has a set C of m-cycles for some positive integer m such that each 2-path of Γ is contained in exactly one cycle in C. If m is the girth of Γ , then the graph is called polygonal. We provide a construction of an infinite family of polygonal graphs of arbitrary even girth with 2-arc transitive automorphism groups, showing that there are infinitely many 2...

One of the basic facts of group theory is that each finite group contains a Sylow p-subgroup for each prime p which divides the order of the group. In this note we show that each vertex-transitive selfcomplementary graph has an analogous property. As a consequence of this fact, we obtain that each prime divisor p of the order of a vertex-transitive self-complementary graph satisfies the congrue...