Titlebook: Discrete Geometry, Combinatorics and Graph Theory; 7th China-Japan Conf Jin Akiyama,William Y. C. Chen,Qinglin Yu Conference proceedings 20

craven

Sufficient Conditions for the Existence of Perfect Heterochromatic Matchings in Colored Graphs,ngs for which the maximum matching problem is solvable in polynomial time, the maximum heterochromatic matching problem is NP-complete. This means that to find both sufficient and necessary good conditions for the existence of perfect heterochromatic matchings should be not easy. In this paper, we o

Exonerate

Impossibility of Transformation of Vertex Labeled Simple Graphs Preserving the Cut-Size Order,be equivalent. From the equivalence, . precedes .′ in the order means that there is a sequence of cross-operations transforming . into .′. However, even if both graphs are simple, non-simple graphs may appear on the way of the transformation. If both graphs have the same number of edges, we conjectu

貧困

連鎖

手工藝品

漂亮才會豪華

繁忙

Isolated Toughness and Existence of ,-Factors,; otherwise, set .(.)?=?|.(.)|???1. Let . and . be two nonnegative integer-valued functions defined on .(.) satisfying .?≤?.(.)?≤?.(.)?≤?. . The purpose in this paper are to present sufficient conditions in terms of the isolated toughness and the minimum degree for graphs to have .-factors and (., .

heirloom

A Note on the Integrity of Middle Graphs,and .(.???.) denote the the subset of . and the order of the largest component of .???., respectively. In this paper, we determine the integrity and some other parameters of middle graphs of some classes of graphs.

兇猛

Indecomposable Coverings, any fixed concave quadrilateral, that cannot be decomposed into two coverings. We also construct, for every .?>?1, a set of points . and a family of disks . in the plane, each containing at least . elements of ., such that no matter how we color the points of . with two colors, there exists a disk

儲備

The Decycling Number of Cubic Planar Graphs,ted cubic planar graphs of order 2. and ., then there exist integers .. and .. such that there exists a graph . with .(.)?=?. if and only if . is an integer satisfying ..?≤?.?≤?... We also find all corresponding integers .. and ... In addition, we prove that if . is the class of all connected cubic