Results 1 to 10 of about 6,027,070 (293)
Cacti with Extremal PI Index [PDF]
Transactions on Combinatorics, 2016 The vertex PI index PI(G)=∑ xy∈E(G) [n xy (x)+n xy (y)] PI(G)=∑xy∈E(G)[nxy(x)+nxy(y)] is a distance-based molecular structure descriptor, where n xy (x) nxy(x) denotes the number of vertices which are closer to the vertex x x than to the vertex y y
Chunxiang Wang, Shaohui Wang , Bing Wei
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PI INDEX OF SOME BENZENOID GRAPHS [PDF]
Journal of the Chilean Chemical Society, 2006 The Padmakar-Ivan (PI) index of a graph G is defined as PI(G) = ∑(n eu (e|G)+ n ev (e|G)), where n eu (e|G) is the number of edges of G lying closer to u than to v, n ev (e|G) is the number of edges of G lying closer to v than to u and summation goes over all edges of G. In this paper, we first compute the PI index of a class of pericondensed benzenoid
REZA ASHRAFI, ALI, LOGHMAN, AMIR
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On vertex PI index of certain triangular tessellation networks
Main Group Metal Chemistry, 2021 The Wiener index, due to its many applications is considered to be one of very important distance-based index. But the Padmaker-Ivan (PI) index is kind of the only distance related index linked to parallelism of edges.
Bokhary Syed Ahtsham Ul Haq, Adnan
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Estimating the PI-Estrada index of graphs [PDF]
Discrete Mathematics Letters, 2021 Summary: Let \(G\) be a graph with \(n\) vertices. The PI-Estrada index of \(G\) is an invariant that is calculated from the eigenvalues of the vertex-PI matrix of \(G\). The main purpose of this paper is to establish upper and lower bounds for the PI-Estrada index of a graph in terms of the number of vertices, edges, triangles and pendant vertices.
Akbar Jahanbani +2 more
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Estimating the Vertex PI Index
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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Computing PI and Szeged indices of multiple phenylenes and cyclic hexagonal-square chain consisting of mutually isomorphic hexagonal chains [PDF]
Journal of the Serbian Chemical Society, 2007 PI and Szeged indices are two of the most important topological indices defined in chemistry. In this study, the PI and Szeged indices of linear [n]-phenylenes and a cyclic hexagonal-square chain consisting of n mutually isomorphic hexagonal chains were ...
Yousefi-Azari H. +3 more
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Effects of irrigation and nitrogen management on hybrid maize seed production in north-west China [PDF]
Frontiers of Agricultural Science and Engineering, 2016 Scientific irrigation and nitrogen management is important for agricultural production in arid areas. To quantify the effect of water and nitrogen management on yield components, biomass partitioning and harvest index (HI) of maize for seed production ...
Hui RAN,Shaozhong KANG,Fusheng LI,Ling TONG,Taisheng DU
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Phase‐index correlation delay shift keying modulation
IET Communications, 2022 High‐data‐rate phase‐orthogonality correlation‐delay‐shift‐keying (HPO‐CDSK) transmits 2‐bits orthogonal signal in parallel and achieve higher spectral efficiency in the category of non‐coherent detection chaotic systems. However, the spectral efficiency
Jun‐Yi Duan, Hua Yang
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Role of 3D Ultrasound and Doppler in Differentiating Clinically Suspected Cases of Leiomyoma and Adenomyosis of Uterus [PDF]
Journal of Clinical and Diagnostic Research, 2015 Introduction: Adenomyosis and Leiomyoma are common disorders affecting females in their reproductive age. They mimic each other in clinical presentation. Due to similarities in clinical symptoms and signs, missing one diagnosis in favour of the other
Kaveri Sharma +7 more
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Forwarding and optical indices of 4-regular circulant networks [PDF]
, 2015 An all-to-all routing in a graph $G$ is a set of oriented paths of $G$, with exactly one path for each ordered pair of vertices. The load of an edge under an all-to-all routing $R$ is the number of times it is used (in either direction) by paths of $R ...
Gan, Heng-Soon +2 more
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