A pair of Mond–Weir type nondifferentiable second-order symmetric primal and dual problems in mathematical programming is formulated. Weak duality, strong duality, and converse duality theorems are established under η-pseudobonvexity assumptions. Symmetric minimax mixed integer primal and...

The Vehicle Routing Problem with Backhauling deals with the supply of finished goods from a depot to a number of delivery points, and picking up returnable items and bringing them back to the depot using a fleet of trucks. Traditionally, the objective of the problem has been to determine the...

The capacitated facility location problem (CFLP) is a well-known combinatorial optimization problem with applications in distribution and production planning. A variety of lower bounds based on Lagrangean relaxation and subgradient optimization has been proposed for this problem. However,...

A widely used method in the analysis of complex econometric models is to replace the "true model" by an aggregative one in which the variables are grouped and replaced by sums or weighted averages of the variables in each group. The analysis of the problem of choosing an aggregative model...

A widely used method in the analysis of complex econometric models is to replace the "true model" by an aggregative one in which the variables are grouped and replaced by sums or weighted averages of the variables in each group. The analysis of the problem of choosing an aggregative model...

In this paper we give a "personal" survey of the research on the polyhedral approach to lot-sizing problems developed over the last ten years. Most results concern the formulation and reformulations of single-item problems which can be used to tighten the formulation of practical multi-item and...