Results 31 to 40 of about 150 (120)
Automatic image segmentation based on label propagation
IET Image Processing, Volume 15, Issue 11, Page 2532-2547, September 2021., 2021 Abstract This article introduces an automatic approach for the segmentation of coloured natural scene images based on graphs and the propagation of labels originally designed for communities detection in complex networks. Images are initially pre‐segmented with super‐pixels, followed by feature extraction using colour information of each super‐pixels ...
Ivar Vargas Belizario +2 more
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On some aspects of the generalized Petersen graph
Electronic Journal of Graph Theory and Applications, 2017 Let $p \ge 3$ be a positive integer and let $k \in {1, 2, ..., p-1} \ \lfloor p/2 \rfloor$. The generalized Petersen graph GP(p,k) has its vertex and edge set as $V(GP(p, k)) = \{u_i : i \in Zp\} \cup \{u_i^\prime : i \in Z_p\}$ and $E(GP(p, k)) = \{u_i ...
V. Yegnanarayanan
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Recent Progress about Flight Delay under Complex Network
Complexity, Volume 2021, Issue 1, 2021., 2021 Flight delay is one of the most challenging threats to operation of air transportation network system. Complex network was introduced into research studies on flight delays due to its low complexity, high flexibility in model building, and accurate explanation about real world. We surveyed recent progress about flight delay which makes extensive use of
Tang Zhixing +3 more
wiley +1 more source
Degree‐Based Indices of Some Complex Networks
Journal of Mathematics, Volume 2021, Issue 1, 2021., 2021 A topological index is a numeric quantity assigned to a graph that characterizes the structure of a graph. Topological indices and physico‐chemical properties such as atom‐bond connectivity (ABC), Randić, and geometric‐arithmetic index (GA) are of great importance in the QSAR/QSPR analysis and are used to estimate the networks. In this area of research,
Lei Ding +7 more
wiley +1 more source
More on the Laplacian Estrada index
Applicable Analysis and Discrete Mathematics, 2009 Let G be a graph with n vertices and let ?1, ?2, . . . , ?n be its Laplacian eigenvalues. In some recent works a quantity called Laplacian Estrada index was considered, defined as LEE(G)?n1 e?i. We now establish some further properties of LEE, mainly upper and lower bounds in terms of the number of vertices, number of edges, and the first Zagreb index.
Bo Zhou, Ivan Gutman
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A New Like Quantity Based on “Estrada Index”
Journal of Inequalities and Applications, 2010 We first define a new Laplacian spectrum based on Estrada index, namely, Laplacian Estrada-like invariant, LEEL, and two new Estrada index-like quantities, denoted by S and EEX, respectively, that are generalized versions of the Estrada index. After that,
A. Dilek Güngör
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On the laplacian estrada index of a graph
Applicable Analysis and Discrete Mathematics, 2009 Let G be a graph of order n. Let ?1 , ?2 , . . . , ?n be the eigenvalues of the adjacency matrix of G, and let ?1 , ?2 , . . . , ?n be the eigenvalues of the Laplacian matrix of G. Much studied Estrada index of the graph G is defined n as EE = EE(G)= ?n/i=1 e?i . We define and investigate the Laplacian Estrada index of the graph G, LEE=LEE(G)= ?n/i=1 e(
Jianxi Li, Chee Shiu, An Chang
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More on the normalized Laplacian Estrada index [PDF]
Applicable Analysis and Discrete Mathematics, 2014 Let G be a simple graph of order N. The normalized Laplacian Estrada index of G is defined as NEE(G)=?Ni=1 e?i?1, where ?1, ?2,... , ?N are the normalized Laplacian eigenvalues of G. In this paper, we give a tight lower bound for NEE of general graphs.
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The normalized Laplacian Estrada index of a graph
Filomat, 2014 In this paper, we define and investigate the normalized Laplacian Estrada index of a graph. Some bounds for the normalized Laplacian Estrada index of a graph in term of its vertex number, maximum (or minimum) degree are obtained, some inequalities between the normalized Laplacian Estrada and the normalized Laplacian energy are also obtained.
Jianxi Li, Ji-Ming Guo, Wai Shiu
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Laplacian Estrada index of trees
, 2011 Let $G$ be a simple graph with $n$ vertices and let $μ_1 \geqslant μ_2 \geqslant...\geqslant μ_{n - 1} \geqslant μ_n = 0$ be the eigenvalues of its Laplacian matrix. The Laplacian Estrada index of a graph $G$ is defined as $LEE (G) = \sum\limits_{i = 1}^n e^{μ_i}$.
Ilic, Aleksandar, Zhou, Bo
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