In recent years, branch-and-cut algorithms have become firmly established as the most effective method for solving generic mixed integer linear programs (MILPs). Methods for automatically generating inequalities valid for the convex hull of solutions to such MILPs are a critical element of branch-and-cut. This paper examines the nature of the so-called separation problem, which is that of gener...

We propose a 3D conforming-nonconforming mixed finite element for solving symmetric stress Stokes equations. The low-order conforming finite elements are not inf-sup stable. The low-order nonconforming finite elements do not satisfy the Korn inequality. The proposed finite element space consists of two conforming components and one nonconforming component. We prove that the discrete inf-sup con...

In this paper we provide a unified treatment of general two-term disjunctions on crosssections of the second-order cone. We derive a closed-form expression for a convex inequality that is valid for such a disjunctive set and show that this inequality is sufficient to characterize the closed convex hull of all two-term disjunctions on ellipsoids and paraboloids, and split disjunctions on all cro...

The goals of hub location problems are finding the location of hub facilities and determining the allocation of non-hub nodes to these located hubs. In this work, we discuss the multi-modal single allocation capacitated p-hub covering problem over fully interconnected hub networks. Therefore, we provide a formulation to this end. The purpose of our model is to find the location of hubs and the ...

We investigate the connection between the validity of certain logarithmic Sobolev inequality and the validity of suitable generalizations of Gagliardo–Nirenberg inequalities. A similar connection holds between reverse logarithmic Sobolev inequalities and a new class of reverse Gagliardo–Nirenberg inequalities, valid for a suitable class of functions. 0. Introduction The main concern of this pap...

Two-step MIR inequalities are valid inequalities derived from a facet of a simple mixedinteger set with three variables and one constraint. In this paper we investigate how to effectively use these inequalities as cutting planes for general mixed-integer problems. We study the separation problem for single constraint sets and show that it can be solved in polynomial time when the resulting ineq...

This paper is devoted to the study of Wirtinger-type inequalities for the Lebesgue∆-integral on an arbitrary time scale T. We prove a general inequality for a class of absolutely continuous functions on closed subintervals of an adequate subset of T. By using this expression and by assuming that T is bounded, we deduce that a general inequality is valid for every absolutely continuous function ...

Necessary and sufficient conditions on V are obtained (in terms of the solvability of a linear pde) for (3) to hold. Analogous results involving improvements are obtained for the weighted versions. We establish optimal inequalities which are similar to (1) and are valid for u ∈ H(Ω). We obtain results on improvements of this inequality which are similar to the above results on improvements. In ...

We consider the class of generalized entropy (GE) measures that are commonly used to measure inequality. When used in the context of very small samples, as is frequently the case in studies of industrial concentration, these measures are significantly biased. We derive the analytic expression for this bias for an arbitrary member of the GE family, using a small-sigma expansion. This expression ...