Showing papers in "Computers & Operations Research in 2007"

TL;DR: A unified heuristic which is able to solve five different variants of the vehicle routing problem and shown promising results for a large class of vehicle routing problems with backhauls as demonstrated in Ropke and Pisinger.

TL;DR: A literature review that covers the entire purchasing process, considers both parts and services outsourcing activities, and covers internet-based procurement environments such as electronic marketplaces auctions is presented.

TL;DR: A PSO algorithm, extended from discrete PSO, for flowshop scheduling, which incorporates a local search scheme into the proposed algorithm, called PSO-LS, and shows that the local search can be really guided by PSO in the approach.

TL;DR: This paper presents a mixed integer nonlinear programming model for the design of a dynamic integrated distribution network to account for the integrated aspect of optimizing the forward and return network simultaneously.

TL;DR: This work tackles the development of efficient capacity planning policies for remanufacturing facilities in reverse supply chains, taking into account not only economic but also environmental issues, such as the take-back obligation imposed by legislation and the “green image” effect on customer demand.

TL;DR: A 0–1 mixed integer programming model is proposed, in which “forward” and “reverse” flows and their mutual interactions are considered and an algorithm based on Lagrangian heuristics is developed and tested on data adapted from classical test problems.

TL;DR: This work presents and compares several multi-objective optimization methods for solving the vendor selection problem, which includes weighted objective, goal programming and compromise programming, and describes the multicriteria models and the methods using a realistic example.

TL;DR: It is argued that six factors, including economics, resource, strategy, risk, management and quality, should be considered for outsourcing decisions, and proposes the use of analytic hierarchy process (AHP) and preference ranking organization method for enrichment evaluations (PROMETHEE) as aids in making IS outsourcing decisions.

TL;DR: This study reviews the selected material in the literature, including more than 70 studies dated 1986 or later, and investigates the applications, mixed integer programming models, and solution methods presented for the hierarchical facility location models.

TL;DR: An efficient variable neighborhood search heuristic for the capacitated vehicle routing problem to design least cost routes for a fleet of identically capacitated vehicles to service geographically scattered customers with known demands is presented.

TL;DR: A heuristic method based on artificial neural networks (NN) is applied in order to trace out the efficient frontier associated to the portfolio selection problem, considering a generalization of the standard Markowitz mean-variance model which includes cardinality and bounding constraints.

TL;DR: This paper reviews some of the most popular technologies that have been identified in the literature for the development of a customer churn management platform, and the advantages and disadvantages of the identified technologies are discussed.

TL;DR: A new multiobjective location-routing model has the objective of minimizing the total cost and the transportation risk and a large-scale implementation of the model in the Central Anatolian region of Turkey is presented.

TL;DR: A variant of the record-to-record travel algorithm for the standard vehicle routing problem to handle open routes, and computational results on test problems taken from the literature are reported.

TL;DR: This work is concerned with the efficient design of a reverse logistics network using an extended version of models currently found in the literature, defined as a mixed integer nonlinear program (MINLP-model) for a single product-single-level network.

TL;DR: A robust heuristic approach is proposed for the VRPTW using travel distance as the main objective through an efficient genetic algorithm and a set partitioning formulation that outperforms all previously known and published heuristic methods in terms of the minimal travel distance.

TL;DR: Heuristic algorithms to solve the vehicle routing problem with simultaneous pick-up and delivery approximately in a small amount of computing time are presented and constructive algorithms, local search algorithms and tabu search algorithms are presented.

TL;DR: This paper identifies factors affecting the BPO decision and structures a decision model using the analytic hierarchy process (AHP) method to assist management in making better decisions in outsourcing their business processes and help them to obtain the most benefits from BPO.

TL;DR: A generic stochastic model for the design of networks comprising both supply and return channels, organized in a closed loop system, based on the branch-and-cut procedure known as the integer L-shaped method is presented.

TL;DR: An approach based on column generation (CG) is applied for its solution, hitherto successful only in the vehicle routing problem with time windows, and outperforms all the existing algorithms both in terms of the quality of solutions generated and the solution time.

TL;DR: The formulation for the decision model and a numerical application to illustrate the use of the model are presented, which integrates both approaches to indicate a contract proposal.

TL;DR: A new enhanced neighborhood structure is proposed and applied to solving the job shop scheduling problem by TS approach and it is shown that for the rectangular problem this approach dominates all others in terms of both solution quality and performance.

TL;DR: A double-level order-up-to rule, so-called 2D rule, is derived, with one level corresponding to ‘young’ platelets and one to the total inventory, which is easy to implement and is shown to be ‘nearly optimal’.

TL;DR: The aim of this paper is to propose tools in order to implicitly consider different preventive maintenance policies on machines regarding flowshop problems by proposing a simple criterion to schedule preventive maintenance operations to the production sequence.

TL;DR: The applied metaheuristic combines the strengths of the well-known guided local search and evolution strategies metaheuristics into an iterative two-stage procedure that provides the best-known solutions to 70 test instances.

TL;DR: The results indicated that scientific methodology for outsourcer management system is very beneficial for the company.

TL;DR: The model yields a plan to re-position the export containers within the yard, so that no extra re-handles will be needed during the loading operation, and the optimization goal is to minimize the number of container movements during pre-marshalling.

TL;DR: An NP-hard production-distribution problem for one product over a multi-period horizon is investigated and metaheuristics that simultaneously tackle production and routing decisions give better results than the GRASP alone.

TL;DR: A variant of the record-to-record travel algorithm for the standard vehicle routing problem that takes a heterogeneous fleet into account is developed, and computational results on eight benchmark problems are reported.

TL;DR: A multi-objective maximal covering-based emergency vehicle location model is proposed that addresses the issue of determining the best base locations for a limited number of vehicles so that the service level objectives are optimized.