distance-balanced graphs are introduced as graphs in which every edge uv has the followingproperty: the number of vertices closer to u than to v is equal to the number of vertices closerto v than to u. basic properties of these graphs are obtained. in this paper, we study theconditions under which some graph operations produce a distance-balanced graph.

The genomic distance problem in the Hannenhalli-Pevzner (HP) theory is the following: Given two genomes whose chromosomes are linear, calculate the minimum number of translocations, fusions, fissions and inversions that transform one genome into the other. This paper presents a new distance formula based on a simple tree structure that captures all the delicate features of this problem in a uni...

fullerenes are closed−cage carbon molecules formed by 12 pentagonal and n/2 – 10hexagonal faces, where n is the number of carbon atoms. patrick fowler in his lecture inmcc 2009 asked about the wiener index of fullerenes in general. in this paper werespond partially to this question for an infinite class of fullerenes with exactly 10ncarbon atoms. our method is general and can be applied to full...

Considering the slow response and unstable velocity of agricultural machinery caused by soil resistance, actuator delay, environmental change, fluctuation, other internal external factors under real working conditions, a kind following control system that considers variable load delay was proposed. Taking distance-keeping, velocity-following, acceleration-following as parameters, controller mod...

A simple connected graph G is said to be interval distance monotone if the interval I (u, v) between any pair of vertices u and v in G induces a distance monotone graph. Aïder and Aouchiche [Distance monotonicity and a new characterization of hypercubes, Discrete Math. 245 (2002) 55–62] proposed the following conjecture: a graph G is interval distance monotone if and only if each of its interva...

Consider the following two graphs M a n d N, both with vertex set Z×Z, where Z is the set of all integers. In M, two vertices are adjacent when their euclidean distance is 1, while in N, adjacency is obtained when the distance is either 1 or 1/2. By definition, H is a metric subgraph of the graph G if the distance between any two points o f / 4 is the same as their distance in G. We determine a...

Computing the minimum distance of a lattice (and vectors achieving the minimum distance) is a fundamental problem in the algorithmic study of lattices, and the core of many applications in computer science and cryptography. Today, we will focus on mathematical properties of lattices, and answer questions like: is the quantity λ(Λ) always achieved by a pair of vectors? (I.e., can the inf in the ...