Results 11 to 20 of about 231,101 (299)

Estimating the Vertex PI Index [PDF]

Zeitschrift für Naturforschung A, 2010
The vertex PI index is a distance-based molecular structure descriptor, that recently found numerous chemical applications. Lower and upper bounds for PI are obtained, as well as results of Nordhaus-Gaddum type.
das, kinkar, Gutman, Ivan
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The PI index of product graphs

Applied Mathematics Letters, 2008
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Hassan Yousefi-Azari, B. Manoochehrian, A. R. Ashrafi   +2 more
openaire   +3 more sources

Bounds On Szeged And Pi Indexes In Terms Of Second Zagreb Index [PDF]

, 2012
In this short note, we studied the vertex version and the edge version of the Szeged index and the PI index and obtained bounds for these indices in terms of the Second Zagreb index. Also, established the connections of bounds to the above sighted indices.
Ranjini P.S., Lokesha, V., Phani Raju, M.   +2 more
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Extremal graphs with respect to the vertex PI index

Applied Mathematics Letters, 2009
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Mohammad J. Nadjafi-Arani, Gholam Hossein Fath-Tabar, A. R. Ashrafi   +2 more
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On the extremal graphs with respect to the vertex PI index

Applied Mathematics Letters, 2010
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Ilić, Aleksandar, Aleksandar Ilić
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Assessment of myocardial performance index in late-onset fetal growth restriction [PDF]

, 2021
The aim of this study is to determine whether the myocardial performance index (MPI) is increased in fetal growth restriction (FGR) fetuses and if increased MPI is related to adverse outcomes of FGR. This is a prospective cross-sectional study.
Nguyen, Tran Thao Nguyen, Nguyen, Dac Nguyen, Yamamoto, Eiko, Kotani, Tomomi, Le, Lam Huong, Le, Minh Tam, Imai, Kenji, Kobayashi, Tomoko, Ushida, Takafumi, Sumigama, Seiji, Nguyen, Vu Quoc Huy, Moriyama, Yoshinori, Kikkawa, Fumitaka, Vo, Van Duc, Niimi, Kaoru, Truong, Quang Vinh, Cao, Ngoc Thanh   +16 more
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On Weighted PI Index of Graphs

Electronic Notes in Discrete Mathematics, 2016
Abstract The vertex PI index of a graph G, denoted by P I v ( G ) , is the sum over all edges uv of G of the number of vertices which are not equidistant from u and v. Similarly, the Weighted PI index of a graph G, denoted by P I w ( G ) = ∑ u v = e ∈ E ( G ) ( d G ( u ) + d G ( v
Kannan Pattabiraman, P. Kandan
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Computation of edge Pi index, vertex Pi index and Szeged index of some cactus chains

Mathematica Montisnigri, 2022
A cactus chain is a connected graph in which all blocks are cycles, each cycle has at most two cut-vertices and each cut-vertex is shared by exactly two cycles. In this paper we give exact values of edge PI index and vertex PI index of an arbitrary cactus chain and vertex Szeged index of some special types of cactus chains.
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The weighted vertex PI index

Mathematical and Computer Modelling, 2013
Abstract The vertex PI index is a distance-based molecular structure descriptor, that recently found numerous chemical applications. In order to increase diversity of this topological index for bipartite graphs, we introduce a weighted version defined as P I w ( G ) = ∑ e = u v ∈ E ( d e g ( u ) + d e g (
Aleksandar Ilic, Nikola Milosavljevic
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On graphs preserving PI index upon edge removal

, 2021
The paper is concerned with the PI index of graphs. Let G be a graph and e its edge. If PI(G) = PI(G- e) , then e is said to be a PI-invariant edge of G. Bipartite graphs have no PI-invariant edges. A general class of non-bipartite graphs is constructed,
Alex L., Indulal G., Gutman, Ivan
core   +1 more source