For a graph G , we denote by N ( ) the number of non-empty subtrees . If is connected, its Wiener index W sum distances between all unordered pairs vertices In this paper establish some comparative results and It shown that > if order n ≥ 7 diameter 2 or 3. Also graphs are constructed with large diameters Moreover, for tree T ≇ S prove starlike maximum degree 3 exactly two degrees one which ...

In this research, a new model development and innovation of conventional boat named plug-in hybrid electric recreational (PHERB) was introduced to overcome the fuel economy nowadays. This paper focus on comparison simulation results PHERB with advanced vehicle simulator (ADVISOR) an automotive analysis tool (AUTONOMIE) models in terms machine, energy system storage, propeller model. The is cons...