Internet worms pose a major threat to Internet infrastructure security, and their destruction will be truly costly. Therefore, the networks must be protected as much as possible against such attacks. In this paper we propose automatic and accurate system for signature generation for unknown polymorphic worms. We have designed a novel double-honeynet system, which is able to detect new worms tha...

As shown in previous work, there is a well-defined nonperturbative gravitational path integral including an explicit sum over topologies in the setting of Causal Dynamical Triangulations in two dimensions. In this paper we derive a complete analytical solution of the quantum continuum dynamics of this model, obtained uniquely by means of a double-scaling limit. We show that the presence of infi...

It is shown that the existence of a Hamiltonian path in a planar automatic graph of bounded degree is complete for Σ1 1 , the first level of the analytical hierarchy. This sharpens a corresponding result of Hirst and Harel for highly recursive graphs. Furthermore, we also show: (i) The Hamiltonian path problem for finite planar graphs that are succinctly encoded by an automatic presentation is ...

Embedding of paths have attracted much attention in the parallel processing. Many-to-many communication is one of the most central issues in various interconnection networks. A graph G is globally two-equal-disjoint path coverable if for any two distinct pairs of vertices (u, v) and (w, x) of G, there exist two disjoint paths P and Q satisfied that (1) P joins u to v and Q joins w to x, (2) |P ...

We consider a variant of the path cover problem, namely, the k-fixed-endpoint path cover problem, or kPC for short, on interval graphs. Given a graph G and a subset T of k vertices of V (G), a k-fixed-endpoint path cover of G with respect to T is a set of vertex-disjoint paths P that covers the vertices of G such that the k vertices of T are all endpoints of the paths in P . The kPC problem is ...

A Disjoint Path Cover (DPC for short) of a graph is a set of pairwise (internally) disjoint paths that altogether cover every vertex of the graph. Given a set S of k sources and a set T of k sinks, a many-to-many k-DPC between S and T is a disjoint path cover each of whose paths joins a pair of source and sink. It is classified as paired if each source of S must be joined to a designated sink o...

For a graph G and a positive integer k, a subset S of vertices of G is called a k-path vertex cover if every path of order k inG contains at least one vertex from S. The cardinality of a minimum k-path vertex cover is denoted by ψk(G). In this paper, we give some bounds and the exact values in special cases for ψk of the Cartesian, and lexicographic products of some graphs. Key–Words: Vertex co...

A certifying algorithm for a problem is an algorithm that provides a certificate with each answer that it produces. The certificate is a piece of evidence that proves that the answer has not been compromised by a bug in the implementation. A path cover of a graph G = (V,E) is a family of vertex-disjoint paths that covers all vertices in V . Given a graph G, the path cover problem is to find a p...

A 3-path vertex cover in a graph is a vertex subset C such that every path of three vertices contains at least one vertex from C. The parameterized 3-path vertex cover problem asks whether a graph has a 3-path vertex cover of size at most k. In this paper, we give a kernel of 5k vertices and an O(1.7485)-time polynomial-space algorithm for this problem, both new results improve previous known b...

In this paper, the motion control of a mobile robot, which is based on a specific type of chaotic systems, is studied. These systems produce the well-known from the nonlinear theory double-scroll chaotic attractors. So, the proposed motion control strategy of the mobile robot is based on a chaotic path planning generator in order to cover a terrain fast and with unpredictable way. For choosing ...