Sophie D'Amours

Using Operational Research for Supply Chain Planning in the Forest Products Industry

Abstract Over the years, Operational Research (OR) has been used extensively to support the forest products industry and public forestry organizations (e.g., governments, environmental protection groups) in their respective planning activities concerning the flow of wood fiber from the forest to the customer. The applications deal with a wide range of problems, ranging from long-term strategic problems related to forest management or company development to very short-term operational problems, such as planning for real-time log/chip transportation or cutting. This paper presents an overview of the different planning problems and reviews the past contributions in the field of forestry, with a focus on applications and problem descriptions. In the context of the 50th anniversary of the Canadian Operational Research Society, this paper also recognizes the contributions of many Canadian researchers to the field of forestry management.

Networked manufacturing:: The impact of information sharing

Abstract In this paper we address the impact of information sharing between firms of a manufacturing network. Firms of the network are selected and scheduled to produce an order based on a price–time evaluation of their bids using an optimal planning model for networked manufacturing. Networking strategies, where business relationships are characterized by different levels of shared information on price and capacity, are classified. An illustrative example sketches the impact of information sharing on networked manufacturing using three different kinds of bidding protocol expressing how firms aggregate their information to conform to networking requirements. Finally, the results show that higher networking flexibility in terms of price–time alternatives can be achieved when firms favor tight partnership relations, offering consequently a better scheduling performance.

A strategic framework for networked manufacturing

Abstract This paper introduces a strategic framework for designing and operating agile manufacturing networks, enabling to collaboratively plan, control and manage day-to-day contingencies in a dynamic environment. It is based on a distributed collaborative vision of manufacturing systems. We first introduce a network-oriented organizational strategy according to which a manufacturing business dynamically organizes its operations through the configuration and activation of a distributed network of interdependent responsible manufacturing centers. Then, we present a collaborative relationships strategy as a contractual approach to implement operational networks. Finally, we introduce an operational strategy, showing how this networked collaborative approach can be used to manage day-to-day activities and contingencies in a close-to-reality manner. The concepts underlying the strategic framework are illustrated using a simplified case inspired by our manufacturing partner, a world-class motorcoach manufacturer.

Information Sharing as a Coordination Mechanism for Reducing the Bullwhip Effect in a Supply Chain

The bullwhip effect is an amplification of the variability of the orders placed by companies in a supply chain. This variability reduces the efficiency of supply chains, since it incurs costs due to higher inventory levels and supply chain agility reduction. Eliminating the bullwhip effect is surely simple; every company just has to order following the market demand, i.e., each company should use a lot-for-lot type of ordering policy. However, many reasons, such as inventory management, lot-sizing, and market, supply, or operation uncertainties, motivate companies not to use this strategy. Therefore, the bullwhip effect cannot be totally eliminated. However, it can be reduced by information sharing, which is the form of collaboration considered in this paper. More precisely, we study how to separate demand into original demand and adjustments. We describe two principles explaining how to use the shared information to reduce the amplification of order variability induced by lead times, which we propose as a cause of the effect. Simulations confirm the value of these two principles with regard to costs and customer service levels

Integration of reverse logistics activities within a supply chain information system

This article deals with problems related to the file integration of reverse logistics activities within an organization and to the coordination of this new system. Reverse logistics activities refer to the recovery and processing of unused products and to the redistribution of reusable materials. For better control and management of these activities, new approaches and information support system are proposed here. A new organizational system, which represents the course of the operational processes and the management of the organizations resources (labor, material, etc.), and an information system architecture are proposed for a rehabilitation center.

A framework for an efficient implementation of logistics collaborations

In order to beat the competition, access new markets and respect operational, social and environmental constraints, enterprises establish collaborations with many other business entities. Furthermore, with costs and information sharing, organizations have the opportunity to optimize their logistics activities. However, each enterprise has its own objectives and typically makes its own planning decisions to meet these objectives. Therefore, it becomes crucial to determine how business entities will work together as well as the value of the collaboration. Specifically, it is necessary to identify how logistics activities will be planned and executed, who will take the leadership of the collaboration and how benefits will be shared. In this article, we explain how efficiently build and manage inter-firms relationships. Moreover, we propose five coordination mechanisms that contribute to ensure information sharing, the coordination of logistics activities and the share of benefits. Case studies are used to demonstrate the utility of the framework.

Supply Chain Management and Multiagent Systems: An Overview

This chapter introduces the topic of this book by presenting the fields of supply chain management, multiagent systems, and the merger of these two fields into multiagent-based supply chain management. More precisely, the problems encountered in supply chains and the techniques to address these problems are first presented. Multiagent systems are next broadly presented, before focusing on how agents can contribute to solving problems in supply chains.

Cost allocation in the establishment of a collaborative transportation agreement—an application in the furniture industry

Transportation is an important part of the Canadian furniture industry supply chain. Even though there are often several manufacturers shipping in the same market region, coordination between two or more manufacturers is rare. Recently, important potential cost savings and delivery time reduction have been identified through transportation collaboration. In this paper we propose and test on a case study involving four furniture companies, a logistics scenario that allows transportation collaboration. Moreover, we address the key issue of cost savings sharing, especially when heterogeneous requirements by each collaborating company impact the cost-savings. To do so, we propose a new cost allocation method that is validated through a case study. Sensibility analysis and details about the actual outcome of the case study complete the discussion.

Multi-item dynamic production-distribution planning in process industries with divergent finishing stages

This paper examines a multi-item dynamic production-distribution planning problem between a manufacturing location and a distribution center. Transportation costs between the manufacturing location and the distribution center offer economies of scale and can be represented by general piecewise linear functions. The production system at the manufacturing location is a serial process with a multiple parallel machines bottleneck stage and divergent finishing stages. A predetermined production sequence must be maintained on the bottleneck machines. A tight mixed-integer programming model of the production process is proposed, as well as three different formulations to represent general piecewise linear functions. These formulations are then used to develop three equivalent mathematical programming models of the manufacturer-distributor flow planning problem. Valid inequalities to strengthen these formulations are proposed and the strategy of adding extra 0-1 variables to improve the branching process is examined. Tests are performed to compare the computational efficiency of these models. Finally, it is shown that by adding valid inequalities and extra 0-1 variables, major computational improvements can be achieved.

Synchronized production-distribution planning in a single-plant multi-destination network

This paper examines the flow synchronization problem between a manufacturing location and multiple destinations. Multiple products can be shipped from the manufacturing location to different locations via multiple transportation modes. These transportation modes may have different transportation lead times. The transportation costs structure of the different transportation modes offer economies of scale and can be represented by general piecewise linear functions. The production system at the manufacturing location is a serial process with a bottleneck stage. At the bottleneck stage, a predetermined production sequence must be maintained as is the case in some process-based industries. We propose a tight mixed integer programming model for integrated planning of production and distribution in the network. We show that by adding simple valid inequalities and special 0-1 variables, major computational improvements can be achieved when solving this problem with commercial solvers such as Cplex. We also propose a sequential solution approach, based on the independent, but synchronized, solutions of the production and distribution sub-problems. Finally, the solution methods proposed are tested experimentally for realistic problems and the advantage of integrated planning over independent but synchronized planning is assessed.