Federico Pasin

An integrated model for logistics network design

In this paper we introduce a new formulation of the logistics network design problem encountered in deterministic, single-country, single-period contexts. Our formulation is flexible and integrates location and capacity choices for plants and warehouses with supplier and transportation mode selection, product range assignment and product flows. We next describe two approaches for solving the problem---a simplex-based branch-and-bound and a Benders decomposition approach. We then propose valid inequalities to strengthen the LP relaxation of the model and improve both algorithms. The computational experiments we conducted on realistic randomly generated data sets show that Benders decomposition is somewhat more advantageous on the more difficult problems. They also highlight the considerable performance improvement that the valid inequalities produce in both solution methods. Furthermore, when these constraints are incorporated in the Benders decomposition algorithm, this offers outstanding reoptimization capabilities.

Quality management practices and their impact on performance

Purpose – This paper aims to explore the relationship between quality management practices and their impact on performance.Design/methodology/approach – First, critical quality management practices are identified and classified in three main categories: management, infrastructure, and core practices. Then, a model linking these practices and performance is proposed and empirically tested. The empirical data were obtained from a survey of 133 Tunisian companies from the plastic transforming sector.Findings – The results reveal a positive relationship between quality management practices and organizational performance. Moreover, the findings show a significant relationship between management and infrastructure practices. In addition, the results illustrate a direct effect of infrastructure practices on operational performance and of core practices on product quality.Research limitations/implications – The conceptual model proposed and tested in this study can be used by researchers for developing quality ma...

The impact of a simulation game on operations management education

This study presents a new simulation game and analyzes its impact on operations management education. The proposed simulation was empirically tested by comparing the number of mistakes during the first and second halves of the game. Data were gathered from 100 teams of four or five undergraduate students in business administration, taking their first course in operations management. To assess learning, instead of relying solely on an overall performance measurement, as is usually done in the skill-based learning literature, we analyzed the evolution of different types of mistakes that were made by students in successive rounds of play. Our results show that although simple decision-making skills can be acquired with traditional teaching methods, simulation games are more effective when students have to develop decision-making abilities for managing complex and dynamic situations.

Scheduling technicians and tasks in a telecommunications company

This paper proposes a construction heuristic and an adaptive large neighborhood search heuristic for the technician and task scheduling problem arising in a large telecommunications company. This problem was solved within the framework of the 2007 challenge set up by the French Operational Research Society (ROADEF). The paper describes the authors’ entry in the competition which tied for second place.

A DYNAMIC GAME OF OPERATIONS AND MARKETING MANAGEMENT IN A SUPPLY CHAIN

The aim of the paper is to study some important differences between (classical) non-cooperative and (modern) cooperative supply chain management. For this purpose, the paper develops a differential game model involving operations and marketing activities that are performed by a manufacturer and a retailer in a simple two-member supply chain. We consider a particular single brand of the manufacturer. The manufacturer decides on production volume, production process improvement and national advertising efforts, while the retailer decides her purchase volume by the manufacturer and her pricing policy toward the final consumers. A revenue sharing contract is employed in the non-cooperative setting. Among the issues addressed on the manufacturer side are the trade-off between production and process improvement activities, the path of inventory over time, and the trade-off between attracting new customers and improving the loyalty of current customers. For the retailer we study the inventory and price evolution over time.

Iterated tabu search for the car sequencing problem

This paper introduces an iterated tabu search heuristic for the daily car sequencing problem in which a set of cars must be sequenced so as to satisfy requirements from the paint shop and the assembly line. The iterated tabu search heuristic combines a classical tabu search with perturbation operators that help escape from local optima. The resulting heuristic is flexible, easy to implement, and fast. It has produced very good results on a set of test instances provided by the French car manufacturer Renault.

Quality improvement and goodwill accumulation in a dynamic duopoly

Abstract This paper analyzes optimal advertising and quality improvement decisions by duopolist firms competing in a dynamic setting. An extended version of the Lanchester model is formulated where conformance quality and goodwill are both involved in competition for market share. Each competitor’s new customer attraction rate depends on its own goodwill, while the disloyalty rate for current customers is influenced by the proportion of defective items. The search for a non-cooperative solution by qualitative as well as numerical means leads to definition of the optimal path for advertising and improvement efforts for each competitor, examined under a wide range of configurations.

A large neighbourhood search heuristic for the aircraft and passenger recovery problem

This paper introduces a large neighbourhood search heuristic for an airline recovery problem combining fleet assignment, aircraft routing and passenger assignment. Given an initial schedule, a list of disruptions, and a recovery period, the problem consists in constructing aircraft routes and passenger itineraries for the recovery period that allow the resumption of regular operations and minimize operating costs and impacts on passengers. The heuristic alternates between construction, repair and improvement phases, which iteratively destroy and repair parts of the solution. The aim of the first two phases is to produce an initial solution that satisfies a set of operational and functional constraints. The third phase then attempts to identify an improved solution by considering large schedule changes while retaining feasibility. The whole process is iterated by including some randomness in the construction phase so as to diversify the search. This work was initiated in the context of the 2009 ROADEF Challenge, a competition organized jointly by the French Operational Research and Decision Analysis Society and the Spanish firm Amadeus S.A.S., in which our team won the first prize.

An application of simulation to analyse resource sharing among health‐care organisations

In the field of inventory management, it is a well‐known fact that centralisation, by sharing the risk between several entities, helps reduce the inventory required to provide a certain level of service. In practice, centralisation can be difficult to accomplish, because improvements to the system’s general performance may be achieved at the expense of some of the entities involved. This paper describes a simulation‐based methodology used to study the impacts of equipment pooling on a group of local community service centres (CLSCs) in the Montreal (Canada) region. In addition to quantifying the benefits of the pooling process, the approach allowed the stakeholders to reach an agreement by appraising various pooling scenarios and identifying the conditions that would help ensure fairness.

A dynamic game with monopolist manufacturer and price-competing duopolist retailers

The paper considers a dynamic game with a single manufacturer who supplies two retailers. The manufacturer determines his production rate of a specific product, the rate of quality improvement efforts as well as the rate of advertising for the product. Each retailer controls her purchasing rate and the consumer sales price. Payments from a retailer to the manufacturer are determined by a wholesale price or a revenue-sharing scheme. The retailers operate in the same consumer market in which they compete in prices for the consumer demand. Nash equilibrium conditions are derived and numerical methods are employed to characterize equilibrium behavior of the players in a differential game of fixed and finite duration.