Results 221 to 230 of about 140,001 (255)

Bounds for the Randić Connectivity Index

Journal of Chemical Information and Computer Sciences, 1999
For a saturated hydrocarbon with n carbon atoms and m carbon-carbon bonds and with Randic connectivity index chi, two functions, L = L(n,m) and U = U(n,m), are determined, such that L < or = chi < U. These bounds are better than those previously reported; for most chemically relevant values of n and m there exist hydrocarbons for which chi = L or chi =
Ivan Gutman, Oswaldo Araujo, Daniel A. Morales   +2 more
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On a novel connectivity index

Journal of Mathematical Chemistry, 2009
We present a novel connectivity index for (molecular) graphs, called sum-connectivity index and give several basic properties for this index, especially lower and upper bounds in terms of graph (structural) invariants. It appears that this and the original Randić connectivity index that we call product- connectivity index are highly intercorrelated ...
Bo Zhou, Nenad Trinajstić, Trinajstić Nenad   +2 more
exaly   +3 more sources

A Validity Index Based on Connectivity

2009 Seventh International Conference on Advances in Pattern Recognition, 2009
In this paper we have developed a connectivity based cluster validity index. This validity index is able to detect the number of clusters automatically from data sets having well separated clusters of any shape, size or convexity. The proposed cluster validity index, connect-index, uses the concept of relative neighborhood graph for measuring the ...
Sriparna Saha 0001, Sanghamitra Bandyopadhyay   +1 more
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Comparison between the Szeged index and the eccentric connectivity index

Discrete Applied Mathematics, 2015
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Kinkar Ch Das, M J Nadjafi-Arani
exaly   +2 more sources

On the additive version of the connectivity index

AIP Conference Proceedings, 2012
A novel version of the Randic connectivity index that we call the product-connectivity index, named the sumconnectivity index, is tested on modeling retention indices of lower alkanes and cycloalkanes. The model obtained based on the sum-connectivity index is compared to the model based on the product-connectivity index.
Nikolic, Sonja, Trinajstic, Nenad, Ivaniš Turk, Sanja   +2 more
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Molecular Connectivity and Retention Indexes

Journal of Pharmaceutical Sciences, 1977
The molecular connectivity indexes, chi, of some alcohols, ethers, esters, and ketones did not correlate very well with their retention volumes in some GLC systems. It was concluded that the utility of chi for the prediction of biological activities could prove rather limited.
Y, Michotte, D L, Massart
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On the eccentric connectivity index and Wiener index of a graph

Quaestiones Mathematicae, 2014
Click on the link to view the abstract.Keywords: Eccentricity, eccentric connectivity index, minimum degreeQuaestiones Mathematicae 37(2014), 39 ...
Dankelmann, P, Morgan, MJ, Mukwembi, S, Swart, HC   +3 more
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Wiener Index of k-Connected Graphs

Journal of Interconnection Networks, 2021
The Wiener index [Formula: see text] of a connected graph [Formula: see text] is the sum of distances of all pairs of vertices in [Formula: see text]. In this paper, we show that for any even positive integer [Formula: see text], and [Formula: see text], if [Formula: see text] is a [Formula: see text]-connected graph of order [Formula: see text], then
Xiang Qin, Yanhua Zhao, Baoyindureng Wu
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On the connectivity index of trees

Journal of Mathematical Chemistry, 2007
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Jiang, Yue, Lu, Mei
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The Sum-Connectivity Index - An Additive Variant of the Randić Connectivity Index

Current computer-aided drug design, 2013
Applications of novel variant of the connectivity index that we call here the sum- connectivity index in structure-property modeling are reviewed. Accordingly, we named here the Randić connectivity index as the product-connectivity index. Correlations from literature that were obtained by one-descriptor models using both variants of connectivity ...
Bešlo, Drago, Skala, Karolj, Sović, Ivan, Lučić, Bono, Nikolić, Sonja, Trinajstić, Nenad, Plavšić, Dejan, Vikić-Topić, Dražen   +7 more
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