In this paper we characterize those forbidden triples of graphs, no one of which is a generalized claw, su2cient to imply that a 2-connected graph of su2ciently large order is hamiltonian. c © 2002 Elsevier Science B.V. All rights reserved.

No silicon fabrication and characterization of circuits with topologies designed by evolution has been done before, leaving open questions about the feasibility of the evolutionary design approach, as well as on how highperformance, robust, or portable such designs could really be when implemented in hardware. This paper is the first to report on a silicon implementation of circuits evolved in ...

A poset P = (X,≺) is a unit OC interval order if there exists a representation that assigns an open or closed real interval I(x) of unit length to each x ∈ P so that x ≺ y in P precisely when each point of I(x) is less than each point in I(y). In this paper we give a forbidden poset characterization of the class of unit OC interval orders and an efficient algorithm for recognizing the class. Th...

Let P be a hereditary property. Let kP(G) denote the number of forbidden subgraphs, which are contained in G. A graph G is said to be weakly P-saturated, if G ∈ P and the edges of the complement of G can be labelled e1, e2, . . . , el in such way that for i= 0, 1, . . . , l− 1 the inequality kP(Gi+1)> kP(Gi) holds, whereG0=G,Gi+1=Gi + ei andGl =Kn. The minimum possible size of weakly P-saturate...

This paper presents a fully automated microrobotic system based on force/vision referenced control designed for cell mechanical characterization. The design of the prototype combines Scanning Probe Microscopy (SPM) techniques with advanced robotics approaches. As a result, accurate and non-destructive mechanical characterization based on soft contact mechanisms are achieved. The in vitro workin...

In this paper we propose a multipartite version of the classical Turán problem of determining the minimum number of edges needed for an arbitrary graph to contain a given subgraph. As it turns out, here the non-trivial problem is the determination of the minimal edge density between two classes that implies the existence of a given subgraph. We determine the critical edge density for trees and ...

This paper is concerned with the fixed-parameter tractability of the problem of deciding whether a graph can be made into a graph with a specified hereditary property by deleting at most i vertices, at most j edges, and adding at most k edges, where i, j, k are fixed integers. It is shown that this problem is fixed-parameter tractable whenever the hereditary property can be characterized by a f...

Tucker characterized the minimal forbidden submatrices of binary matrices that do not have the consecutive-ones property. We give a linear-time algorithm to find such a minimal one in any binary matrix that does not have the consecutive-ones property. Lekkerkerker and Boland characterized the minimal forbidden induced subgraphs for the class of interval graphs. We give a linear-time algorithm t...

Interval p-graphs were introduced by Brown et al. in 2002 as a generalization of interval bigraphs [D.E. Brown, S.C. Flink and J.R. Lundgren, Congr. Numer. 157 (2002), 79–93]. Little work has been done towards characterizing them. For interval bigraphs the only known forbidden subgraph characterization is for trees. As it appears to be quite difficult to find a forbidden subgraph characterizati...

We examine two criteria for balance of a gain graph, one based on binary cycles and one on circles. The graphs for which each criterion is valid depend on the set of allowed gain groups. The binary cycle test is invalid, except for forests, if any possible gain group has an element of odd order. Assuming all groups are allowed, or all abelian groups, or merely the cyclic group of order 3, we ch...