The maximum common substructure (MCS) problem is of great importance in multiple aspects of chemoinformatics. It has diverse applications ranging from lead prediction to automated reaction mapping and visual alignment of similar compounds. Many different algorithms have been developed [1], both exact and approximate. Since the MCS problem is NP-complete, the strict time constraints of most appl...

We propose a new fast algorithm for solving the Maximum Common Subgraph (MCS) problem. MCS is an NP-complete problem. In this paper, we focus on a special class of graphs, i.e. Planar Triangulation Graphs, which are commonly used in computer vision, pattern recognition and graphics. By exploiting the properties of Planar Triangulation Graphs and restricting the problem to connected MCS, for two...

The complexity of the maximum common connected subgraph problem in partial k-trees is still not fully understood. Polynomial-time solutions are known for degree-bounded outerplanar graphs, a subclass of the partial 2-trees. On the contrary, the problem is known to be NP-hard in vertex-labeled partial 11-trees of bounded degree. We consider series-parallel graphs, i.e., partial 2-trees. We show ...

This paper presents some strong valid inequalities for the Maximum Common Induced Subgraph Problem (MCIS) and the proofs that the inequalities are facet-defining under certain conditions. TheMCIS is an NP-hard problem and, therefore, no polynomial time algorithm is known to solve it. In this context, the study of its polytope can help in the development of more efficient branch-and-bound and br...

Generalized maps are widely used to model the topology of nD objects (such as images) by means of incidence and adjacency relationships between cells (vertices, edges, faces, volumes, ...). In this paper, we introduce distance measures for comparing generalized maps, which is an important issue for image processing and analysis. We introduce a first distance measure which is defined by means of...

this article shows that persian fragments are derived via a'-movement of the remnant plus tp deletion. evidence like case-matching, binding effects, and scope and bound pronouns show that persian fragments result from the application of deletion rule. but prior to this application, fragments are extracted out of the ellipsis site and moved to the left periphery of the sentence. evidence li...

The relationship between two important problems in pattern recognition using attributed relational graphs, the maximum common subgraph and the minimum common supergraph of two graphs, is established by means of simple constructions, which allow to obtain the maximum common subgraph from the minimum common supergraph, and vice versa. On this basis, a new graph distance metric is proposed for mea...

Penetrating explosive fragments are the most common cause of neck injuries sustained by UK service personnel deployed to Afghanistan. Analysis of these fragments will enable future ballistic protective materials to be tested with appropriate projectiles. However, only a small number of fragments excised from the neck have been available for analysis and they are potentially unrepresentative. We...