We prove a decomposition result for locally finite graphs which can be used to extend results on edge-connectivity from finite to infinite graphs. It implies that every 4k-edge-connected graph G contains an immersion of some finite 2k-edge-connected Eulerian graph containing any prescribed vertex set (while planar graphs show that G need not contain a subdivision of a simple finite graph of lar...

By applying the Tutte decomposition of 2{connected graphs into 3{block trees we provide unique structural characterizations of several classes of 2{connected graphs, including minimally 2{connected graphs, minimally 2{edge{connected graphs, critically 2{connected graphs, critically 2{edge{connected graphs, 3{edge{connected graphs, 2{connected cubic graphs and 3{connected cubic graphs. We also g...

Edge detection improves image readability and it is an important part of images preprocessing aimed to their segmentation and automatic recognition of their contents. This paper describes selected methods of edge detection in magnetic resonance images, with the emphasis on the wavelet transform use. The first part briefly describes the mathematical background of the wavelet transform, including...

An automatic two-dimensional mesh generation scheme based on superelement decomposition technique is presented. The proposed approximate skeletal method (ASM) uses shape interrogation techniques on simplified geometric representation of the shape boundary to generate non-intersecting, topologically simple and mappable superelements. A recursive mesh generation scheme, meshing by successive deco...

Suppose Kv is the complete undirected graph with v vertices. Let K4 − e be the graph obtained from K4 by removing one edge. A (K4 − e) group divisible design (briefly (K4 − e)-GDD) of type h is a triple (X,G,B), where G is a partition of X into groups each of size h, B is an edge-disjoint decomposition of the edge set of Kh,h,...,h, the multipartite complete undirected graph with G as the parti...

Let G be a graph whose edges are colored with k colors, and H=(H1,⋯,Hk) be a k-tuple of graphs. A monochromatic H-decomposition of G is a partition of the edge set of G such that each part is either a single edge or forms a monochromatic copy of Hi in color i, for some 1≤i≤k. Let φk(n,H) be the smallest number ϕ, such that, for every order-n graph and every k-edge-coloring, there is a monochrom...

A decomposition of a graph G is a collection ψ of graphs H1, H2, . . . , Hr of G such that every edge of G belongs to exactly one Hi. If each Hi is either an induced path in G, then ψ is called an induced acyclic path decomposition of G and if each Hi is a (induced) cycle in G then ψ is called a (induced) cycle decomposition of G. The minimum cardinality of an induced acyclic path decomposition...

In this paper, we consider the normality or the integer decomposition property (IDP, for short) for Minkowski sums of integral convex polytopes. We discuss some properties on the toric rings associated with Minkowski sums of integral convex polytopes. We also study Minkowski sums of edge polytopes and give a sufficient condition for Minkowski sums of edge polytopes to have IDP.

Edge-coloured directed graphs provide an essential structure for modelling and analysis of complex systems arising in many scientific disciplines (e.g. feature-oriented systems, gene regulatory networks, etc.). One the fundamental problems edge-coloured is detection strongly connected components, or SCCs. The size appearing practice can be enormous both number vertices colours. large prevents u...