Along with the long-term preservation of digital publications the next important goal is public access and in this regard user-centred design of digital repositories. Several repositories worldwide have shown that users are their most critical element. Repositories as such are valuable only if used. The success of the repository is often influenced by the content and the design of the interface...

background: osteoporosis is a serious public health. since the majority of bone mass occurs during adolescence, primary prevention  is important. probably mother’s participation in health education interventions leads to promote health behaviors in children. to assess a lifestyle modifcation intervention focused on mothers and students has an impact on osteoporosis preventive  behaviors in adol...

An almost self-centered graph is a connected of order $n$ with exactly $n-2$ central vertices, and an peripheral $n-1$ vertices. We determine (1) the maximum girth $n$; (2) independence number radius $r$; (3) minimum $k$-regular graph; (4) size (5) possible degrees (6) vertices degree in $n-4$ which second largest possible. Whenever extremal graphs have neat form, we also describe them.

Disorders of the Central Nervous System (CNS) are worldwide causes of morbidity and mortality. In order to further investigate the nature of the CNS research, we generate from an initial reference a controlled vocabulary of CNS disorder-related terms and ontological tree structure for this vocabulary, and then apply the vocabulary in an analysis of the past ten years of abstracts (N = 10,488) f...

Graph-like data structures and rule-based systems play an important role within many branches of computer science. Nevertheless, their symbiosis in the form of graph rewriting systems or graph grammars are not yet popular among software engineers. This is a consequence of the fact that graph grammar tools were not available until recently and of the lack of knowledge about how to use graph gram...

This paper discusses activity graphs, the mathematical formalism underlying the Activity Coordination System, a process-centered system for collaborative work. The activity graph model was developed for the purpose of describing, tracking, and guiding distributed, communication-intensive activities. Its graph-based semantics encompasses the more familiar Petri nets, but has several novel proper...

We discuss general techniques, centered around the “Layerwise Separation Property” (LSP) of a planar graph problem, that allow to develop algorithms with running time c √ k|G|, given an instance G of a problem on planar graphs with parameter k. Problems having LSP include planar vertex cover, planar independent set, and planar dominating set. Extensions of our speed-up technique to basically al...

Choose random pointsX1, X2, X3, . . . independently from a uniform distribution in a unit ball in <. Call Xn a dominator iff distance(Xn, Xi) ≤ 1 for all i < n, i.e. the first n points are all contained in the unit ball that is centered at the n’th point Xn. We prove that, with probability one, only finitely many of the points are dominators. For the special casem = 2, we consider the unit disk...

Let V be a set of distinct points in the Euclidean plane. For each point x 2 V , let sx be the ball centered at x with radius equal to the distance from x to its nearest neighbour. We refer to these balls as the spheres of in uence of the set V . The sphere of in uence graph on V is de ned as the graph where (x; y) is an edge if and only if sx and sy intersect. In this extended abstract, we dem...

Given a planar graph G, the graph theoretic dilation of G is defined as the maximum ratio of the shortestpath distance and the Euclidean distance between any two vertices of G. Given a planar point set S, a triangulation of S that achieves minimum graph theoretic dilation is called a minimum dilation triangulation of S. In this paper, we show that a simple exclusion region for an edge e of the ...