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...

In this paper we analyze the extension of classical smallest enclosing disk problem to case location a polyellipsoid fully cover set demand points in Rd. We prove that is polynomially solvable fixed dimension and mathematical programming formulations for it. also consider some geometric approaches foci polyellipsoids are known. Extensions algorithm by Elzinga-Hearn derived new problem. Moreover...

v

In this paper, we address a particular variation of the Turán problem for the hypercube. Alon, Krech and Szabó (2007) asked “In an n-dimensional hypercube, Qn, and for ` < d < n, what is the size of a smallest set, S, of Q`’s so that every Qd contains at least one member of S?” Likewise, they asked a similar Ramsey type question: “What is the largest number of colors that we can use to color th...