The problem of maximal hub covering as a challenging problem in operation research. Transportation programming seeks to find an optimal location of a set of hubs to reach maximum flow in a network. Since the main structure's parameters of the problem such as origin-destination flows, costs and travel time, change periodically in the real world applications, new issues arise in handling it. In t...

let $r$ be a commutative ring with identity. let $g(r)$ denote the maximal graph associated to $r$, i.e., $g(r)$ is a graph with vertices as the elements of $r$, where two distinct vertices $a$ and $b$ are adjacent if and only if there is a maximal ideal of $r$ containing both. let $gamma(r)$ denote the restriction of $g(r)$ to non-unit elements of $r$. in this paper we study the various graphi...

Abstract The extended Drinfel’d algebra (ExDA) is the underlying symmetry of non-Abelian duality in low-energy effective theory string theory. Non-Abelian U-dualities maximal supergravities have been studied well, but there has no study on dualities half-maximal supergravities. We construct ExDA for d ≥ 4. also find an extension homogeneous classical Yang–Baxter equation these theories.

objective: exercise activity could be an amendment to polycystic ovary syndrome (pcos). however the acute and chronic effects of various exercise intensities on serum leptin levels are ambiguous. this study investigates the acute and chronic responses of various intensities of exercise on serum leptin levels and weights of female rats with pcos. methods: in this semi-empirical study, 80 adult w...

let $g$ be a non-abelian group of order $p^n$‎, ‎where $nleq 5$ in which $g$ is not extra special of order $p^5$‎. ‎in this paper we determine the maximal size of subsets $x$ of $g$‎ ‎with the property that $xyneq yx$ for any $x,y$ in $x$ with‎ ‎$xneq y$‎.

It is shown that every dp-minimal integral domain R a local ring and for non-maximal prime ideal ℘ of R, the localization R℘ valuation ℘R℘ = ℘. Furthermore, if only its residue field infinite or finite maximal principal.