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let g be a connected simple (molecular) graph. the distance d(u, v) between two vertices u and v of g is equal to the length of a shortest path that connects u and v. in this paper we compute some distance based topological indices of h-phenylenic nanotorus. at first we obtain an exactformula for the wiener index. as application we calculate the schultz index and modified schultz index of this ...

This study identified high-risk locations (hotspots) using geographic information systems (GIS) and spatial analysis. Five years of accident data (2013–2017) for the Lokoja-Abuja-Kaduna highway in Nigeria were used. The concentration analysis was conducted mean center Kernel density estimation method. These further verified Moran’s I statistics (spatial autocorrelation) to determine their clust...

Land use change has an important influence on the spatial and temporal distribution of PM2.5 concentration. Therefore, based particulate matter (PM2.5) data from remote sensing instruments land in long time series, Getis-Ord Gi* statistic SP-SDM are employed to analyze pattern its response China. It is found that average increased 25.49 ?g/m3 31.23 during 2000-2016, showing annual growth rate 0...

The forest of Meiji-Jingu shrine was afforested 100 years ago with the aim creating a sublime one century later. In this study, we conducted visual landscape assessment to explore whether had reached status. Specifically, spatial condition associated sublimity and types that made visitors feel were assessed using combination data collected from geotagged visitor employed photography questionnai...

background: doppler indices of umbilical artery are used as indicator of fetal well being. objective: to compare doppler parameters of umbilical artery including pulsatility index (pi) and resistance index (ri) in patients with preeclampsia with those of normal pregnancies and to evaluate the diagnostic characteristics of these parameters in preeclampsia. materials and methods: in a case contro...

let $g$ be a connected graph, and let $d[g]$ denote the double graph of $g$. in this paper, we first derive closed-form formulas for different distance based topological indices for $d[g]$ in terms of that of $g$. finally, as illustration examples, for several special kind of graphs, such as, the complete graph, the path, the cycle, etc., the explicit formulas for some distance based topologica...

drought as a natural but temporary imbalance of water availability is the interaction between natural environment and human life resulting in diminished water resources availability and reduced carrying capacity of the ecosystems. drought indices are essential elements for an efficient drought monitoring system. these indices make the transforming information of climatic anomalies easier and al...

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the padmakar-ivan (pi) index is a wiener-szeged-like topological index which reflectscertain structural features of organic molecules. the pi index of a graph g is the sum of alledges uv of g of the number of edges which are not equidistant from the vertices u and v. inthis paper we obtain the second and third extremals of catacondensed hexagonal systems withrespect to the pi index.