نتایج جستجو برای: the wiener index

تعداد نتایج: 16095485  

Journal: :Ars Mathematica Contemporanea 2015

Journal: :Advances in Linear Algebra & Matrix Theory 2021

Journal: :Journal of Combinatorial Optimization 2020

2016
YAPING MAO ZHAO WANG IVAN GUTMAN Ali Reza Ashrafi I. Gutman

The Wiener index W (G) of a connected graph G is defined as W (G) = ∑ u,v∈V (G) dG(u, v) where dG(u, v) is the distance between the vertices u and v of G. For S ⊆ V (G), the Steiner distance d(S) of the vertices of S is the minimum size of a connected subgraph of G whose vertex set is S. The k-th Steiner Wiener index SWk(G) of G is defined as SWk(G) = ∑ S⊆V (G) |S|=k d(S). We establish expressi...

Journal: :international journal of environmental research 0

gradual decrease of biodiversity related to the rapid industrialization and urbanization is stimulating the fundamental research towards a better understanding of the relationships between biodiversity and ecosystem functioning. present study emphasizes the nature and status of floral diversity in the vicinity of integrated industrial estate-pantnagar, uttarakhand, india (iie-pantnagar).three m...

Journal: :transactions on combinatorics 2014
farzaneh falahati nezhad ali iranmanesh abolfazl tehranian mahdieh azari

‎the second multiplicative zagreb coindex of a simple graph $g$ is‎ ‎defined as‎: ‎$${overline{pi{}}}_2left(gright)=prod_{uvnotin{}e(g)}d_gleft(uright)d_gleft(vright),$$‎ ‎where $d_gleft(uright)$ denotes the degree of the vertex $u$ of‎ ‎$g$‎. ‎in this paper‎, ‎we compare $overline{{pi}}_2$-index with‎ ‎some well-known graph invariants such as the wiener index‎, ‎schultz‎ ‎index‎, ‎eccentric co...

2008
H. YOUSEFI-AZARI A. R. ASHRAFI M. H. KHALIFEH

The Wiener index of a graph G is defined as W(G) = 1/2∑{x,y}⊆V(G)d(x,y), where V(G) is the set of all vertices of G and for x,y ∈ V(G), d(x,y) denotes the length of a minimal path between x and y. In this paper, we first report our recent results on computing Wiener, PI and Balaban indices of some nanotubes and nanotori. Next, the PI and Szeged indices of a new type of nanostar dendrimers are c...

2007
Weigen Yan Bo-Yin Yang Yeong-Nan Yeh

The sum of distances between all vertices pairs in a connected graph is known as the Wiener Index. It is the earliest of the indices that correlates well with many physicochemical properties of organic compounds and as such has been well-studied over the last quarter of a century. A q-analogue of this index, termed the Wiener Polynomial by Hosoya but also known today as the Hosoya Polynomial, e...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه علامه طباطبایی 1390

over the past decades a number of approaches have been applied for forecasting mortality. in 1992, a new method for long-run forecast of the level and age pattern of mortality was published by lee and carter. this method was welcomed by many authors so it was extended through a wider class of generalized, parametric and nonlinear model. this model represents one of the most influential recent d...

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