Operations Research articles from September 2003

Operations Research archives from September 2003

Still flowing: approaches to traffic flow and traffic jam modeling.(Invited paper)
September 1, 2003... Certain aspects of traffic flow measurements imply the existence of a phase transition. Models known from chaos and fractals, such as nonlinear analysis of coupled differential equations, cellular automata, or coupled maps, can generate...

Drift or shift? Continuity, change, and international variation in knowledge production in OR/MS.(OR chronicle)
September 1, 2003... With the aim of contributing to the debate around OR/MS as a discipline, this study provides a historical comparative investigation of publicly available knowledge production in the field. The empirical investigation is based on a content...

Explicit solutions of optimization models and differential games with nonsmooth (asymmetric) reference-price effects.
September 1, 2003... Models in marketing with asymmetric reference effects lead to nonsmooth optimization problems and differential games which cannot be solved using standard methods. In this study, we introduce a new method for calculating explicitly optimal...

A dynamic model for inventory lot sizing and outbound shipment scheduling at a third-party warehouse.
September 1, 2003... This paper presents a model for computing the parameters of an integrated inventory replenishment and outbound dispatch scheduling policy under dynamic demand considerations. The optimal policy parameters specify (i) how often and in what...

Necessary and sufficient conditions for delay moments in FIFO multiserver queues with an application comparing s slow servers with one fast one.(first-in first-out)
September 1, 2003... In this paper we establish the weakest known sufficient conditions for the existence of stationary delay moments in FIFO GI/GI/s queues, for s [greater than or equal to] 2. These conditions involve not only the service time distribution, as in...

The ordered open-end bin-packing problem.
September 1, 2003... We study a variant of the classical bin-packing problem, the ordered open-end bin-packing problem, where first a bin can be filled to a level above 1 as long as the removal of the last piece brings the bin's level back to below 1 and second,...

A three-stage model for a decentralized distribution system of retailers.
September 1, 2003... We present and study a three-stage model of a decentralized distribution system consisting of n retailers, each of whom faces a stochastic demand for an identical product. In the first stage, before the demand is realized, each retailer...

Efficient algorithms for the inverse spanning-tree problem.
September 1, 2003... The inverse spanning-tree problem is to modify edge weights in a graph so that a given tree T is a minimum spanning tree. The objective is to minimize the cost of the deviation. The cost of deviation is typically a convex function. We propose...

From fluid relaxations to practical algorithms for high-multiplicity job-shop scheduling: the holding cost objective.
September 1, 2003... We design an algorithm for the high-multiplicity job-shop scheduling problem with the objective of minimizing the total holding cost by appropriately rounding an optimal solution to a fluid relaxation in which we replace discrete jobs with the...

Using ranking and selection to "clean up" after simulation optimization.
September 1, 2003... In this paper we address the problem of finding the simulated system with the best (maximum or minimum) expected performance when the number of systems is large and initial samples from each system have already been taken. This problem may be...

An exact algorithm for the two-constraint 0-1 knapsack problem.
September 1, 2003... We consider a knapsack problem in which each item has two types of weight and the container has two types of capacity. We discuss the surrogate, Lagrangian, and continuous relaxations, and give an effective method to determine the optimal...