Results 1 to 10 of about 213,453 (163)
Cacti with Extremal PI Index [PDF]
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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Estimating the PI-Estrada index of graphs [PDF]
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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On the square PI index of graphs [PDF]
Liju Alex +3 more
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The vertex PI index and Szeged index of bridge graphs [PDF]
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Toufik Mansour, Matthias Schork
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On vertex PI index of certain triangular tessellation networks
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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Computing PI and Szeged indices of multiple phenylenes and cyclic hexagonal-square chain consisting of mutually isomorphic hexagonal chains [PDF]
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]
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
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]
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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The PI Index of polyomino chains
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Lixing Xu, Shubo Chen
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