the wiener index w(g) of a connected graph g is defined as the sum of the distances betweenall unordered pairs of vertices of g. the eccentricity of a vertex v in g is the distance to avertex farthest from v. in this paper we obtain the wiener index of a graph in terms ofeccentricities. further we extend these results to the self-centered graphs.

Assessment of performance in tracking set-point changes for single loop systems is presented. In contrast to the works that used stochastic performances, the current assessment uses a deterministic performance measure, i.e. the integration of absolute tracking errors (abbr. IAE). A benchmark system that has an open loop transfer function (abbr. OLTF) comprised of one LHP zero, one integrator, a...

The aim of the present study was to examine whether the relationship between motor coordination and academic achievement is mediated by working memory (WM) in a normative adolescent sample. Participants included 93 adolescents aged 12-16. The Movement Assessment Battery for Children-2 provided three indicators of motor coordination (Manual Dexterity, Aiming and Catching, and Balance), the WM In...

Changes in rank-dependent income-related health inequality measures over time may usefully be decomposed into contributions due to changes in health outcomes and changes in individuals' positions in the income distribution. This paper establishes the normative implications of this type of decomposition by embedding it within a broader analysis of changes in the 'health achievement' index. We fu...

The personality construct of geekism is introduced as the tendency to act out one’s need for cognition in the domain of computing technology. Achievement goal theory is introduced, and we ask, what drives geeks in terms of achievement. In a questionnaire study, it is shown that geekism is related to achievement motivation in imagined situations with technology. Need for cognition showed strong ...

This study was an attempt to find out whether co-teaching model has statistically any significant impact on improving motivation and achievement of Iranian Young EFL Learners or not. The study was conducted at Salehin English Language Department in Tehran. To accomplish the purpose of this study, the researchers chose a sample of 91 participants which was reduced to 62 homogenous students throu...

In this paper we develop a new and generic theory about the necessary and sufficient conditions for deadlock-free routing in the interconnection networks An extension of the channel dependency graph described by Dally is defined, the channel dynamic dependency graph. The main achievement of this new concept is consecuence of introducing the concept of time and the flow control function in its d...