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This paper examines the short term production planning problem encountered in the fine-paper industry. In this industry, different types of pulp are transformed by parallel papermachines into large rolls of paper sheets. The paper sheets are then cut and packaged based oncustomer needs. The paper machines usually represent the bottleneck stage in the productionprocess. At this bottleneck stage, a predetermined production sequence has to be maintained.The paper proposes a tight mixed-integer programming formulation to model this productionprocess. It is showed that real size problem instances can be solved with commercial integerprogramming solvers. Furthermore, we show that by adding some simple valid inequalities tothe proposed formulation, major improvements to the solution time can be achieved

Factors such as tariffs, exchange rates, income tax legislations, national factors of production (e.g. natural resources supply, labour and infrastructure), transfer prices, trade barriers and competition (e.g. world wide distribution of capacity and demand) may have an important impact on company performance. In this paper, we discuss the international factors that may have an important impact on the structure of the value creation networks of Canadian pulp and paper companies, and we show how they could be incorporated in a global supply chain optimization model. To do this, we use a simplified production-distribution network structure in order to emphasize the role of international factors without complicating the analysis. The global network considered is composed of four echelons: fiber and pulp suppliers, pulp and paper mills, distribution centers and demand zones. We provide some modeling elements for the construction of a global optimization model through the synthesis of the existing literature on international network design. We conclude with a discussion of modeling extensions required to obtain network optimization models adequate for decision support in the pulp and paper industry.

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This chapter examines the short term production, transportation and inventory planning problems encountered in the fine-paper industry. After positioning the problems in the context of a general supply chain planning system for the pulp and paper industry, a comprehensive synchronized production-distribution model is gradually developed. First, a model for the dynamic lot-sizing of intermediate products on a single paper machine with a predetermined production cycle is proposed. The model also plans the production and inventory of finished products. Then, we consider the lot-sizing of intermediate products on multiple parallel paper machines with a predetermined production sequence. Finally, simultaneous production and distribution planning for a single mill multiple distribution centers network is studied by considering different transportation modes between the mill and its Distribution Centers (DCs).

This paper presents a novel strategic planning model for optimising fibre resource allocation in the pulp and paper industry. The model is a large mixed-integer program which maximises value creation by using known relationships belween fibre properties and pulp and paper properties to match fibre resources with the processes and end-products to which they are best suited. I can be used to identify optimal fibre allocation practices and to assess the economic potential of new processes and end-products.

The wood fibre based product industry is one of the most important for countries such as Sweden, Finland, Russia and Canada., 0

In this paper we propose a generic planning model for the pulp and paper supply chain. We first review the different business units of the supply chain and the material flows. We then propose a supply chain and paper industry. We further extend the discussion by adressing the difficult problem of distributed planning, even in a hierarchically organized system. To conclude, we propose a multi-agent framework to simulate different configurations of supply chain and anticipate the impact of the different decision models used by the different business units of the supply chain.

The wood fibre based product industry is one of the most important for countries such as Sweden, Finland, Russia and Canada., 0

Les tarifs douaniers, les taux de change, les taux d’imposition des entreprises, les facteurs nationaux de production (ressources naturelles, main-d’œuvre, capital et infrastructures), les prix de transfert, les barrières commerciales et la distribution géographique de l’offre et de la demande sont des facteurs qui ont un impact important sur la performance d’une compagnie multinationale. Or, la position relative des pays par rapport à la majorité de ces facteurs évolue dans le temps. Pour demeurer concurrentielles, les entreprises multinationales doivent donc adapter périodiquement la structure de leurs réseaux de création de valeur aux changements structuraux des facteurs internationaux. Cet article montre que ce constat est particulièrement valable pour les compagnies canadiennes de pâtes et papiers. Après avoir analysé l’évolution des facteurs internationaux qui façonnent la performance de ces compagnies, nous indiquons comment les modèles d’optimisation des réseaux logistiques couramment disponibles peuvent être utilisés pour restructurer les réseaux de création de valeur des compagnies. L’article se termine par une discussion sur les extensions nécessaires aux modèles existants d’optimisation de réseaux afin de rendre compte de l’ensemble des facteurs importants pour l’industrie des pâtes et papiers., Customs fees, exchange rates, business tax rates, national production factors (natural resources, labour, capital and infrastructures), transfer price, trade barriers and geographical distribution of supply and demand are all factors that have a major impact on the performance of a multinational company. The relative position of countries regarding most of these factors evolves over time. To stay competitive, multinational businesses must therefore periodically restructure their value creation networks to adapt to structural changes in international factors. This article shows that such observations are particularly true of Canadian pulp and paper companies. After analyzing the evolution of international factors that shape the performance of these companies, we indicate how currently available logistics network optimization models can be used to restructure these companies’ value creation networks. The article ends with a discussion of the need to extend existing models of network optimization to more fully embrace all factors crucial to the pulp and paper industry., Aranceles, tipo de cambio, tipo impositivo a empresas, factores nacionales de producción (recursos naturales, mano de obra, capital e infraestructuras), costos de transferencia, barreras comerciales y distribución geográfica de oferta y demanda, son factores que tienen una fuerte incidencia sobre el desempeño de una empresa transnacional causando que la posición relativa de los países frente a la mayoría de estos factores evolucione con el tiempo. Para mantenerse competitivas, las transnacionales deben, por ende, adecuar regularmente la estructura de sus redes de creación de valor en función de los cambios estructurales de los factores internacionales. En este artículo se explica que esta observación se aplica particularmente a las empresas papeleras canadienses. Después haber estudiado la evolución de los factores internacionales que influyen en el desempeño de estas empresas se indica cómo los modelos de optimización de redes logísticas comúnmente disponibles pueden servir para reestructurar las redes de creación de valor de las empresas. El artículo concluye con una discusión sobre la necesaria expansión de los modelos actuales de optimización de redes para que estos consideren la globalidad de los factores importantes para la industria papelera.

The research leading to the modeling framework presented in this paper was motivated by the need to provide Canadian pulp and paper producers with a means of maximizing the value created from available fibre supplies. The proposed approach involves finding optimal strategies for partitioning fibre supplies into grades, allocating fibre grades to process streams, selecting appropriate production technologies and capacities, and establishing end-product range compositions and production volumes. These strategies are elaborated with a mixed-integer programming model which can be solved using commercial optimization software. Three test case scenarios are used to validate the model and illustrate how it can be applied to strategic and tactical decision making. A variant of this model has also been applied to an industrial planning problem.

The pulp and paper industry depends on a long and integrated supply chain. Forest products start in forest harvest areas as trees and end up as multiple products used in the dayto-day life of all people. The lead time from the first step to the last is long and involves many steps operated by several companies and organizations. In this overview paper we describe the supply chain in its entirety, its participants and the planning problems arising along the chain. We divide the planning problems into strategic, tactical and operative in a supply chain matrix, describe their characteristics and provide applications as illustrations. We discuss the need for information and decision support for planners in each of these areas. This relates to planning within a single company as well as integrated planning across several. A number of tailor-made systems have been developed and published in the literature and we describe these tools/systems together with their characteristics and results. We conclude with a discussion of current issues and outline future research areas.

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.

One of the important objectives of supply chain S&OP (Sales and Operations Planning) is the profitable alignment of customer demand with supply chain capabilities through the coordinated planning of sales, production, distribution, and procurement. In the make-to-order manufacturing context considered in this paper, sales plans cover both contract and spot sales, and procurement plans require the selection of supplier contracts. S&OP decisions also involve the allocation of capacity to support sales plans. This article studies the coordinated contract selection and capacity allocation problem, in a three-tier manufacturing supply chain, with the objective to maximize the manufacturer's profitability. Using a modeling approach based on stochastic programming with recourse, we show how these S&OP decisions can be made taking into account economic, market, supply, and system uncertainties. The research is based on a real business case in the Oriented Strand Board (OSB) industry. The computational results show that the proposed approach provides realistic and robust solutions. For the case considered, the planning method elaborated yields significant performance improvements over the solutions obtained from the mixed integer programming model previously suggested for S&OP.

Fine paper mills produce a variety of paper grades to satisfy demand for a large number of sheeted products. Huge reels of different paper grades are produced on a cyclical basis on paper machines. These reels are then cut into rolls of smaller size which are then either sold as such, or sheeted into finished products in converting plants. A huge number of roll sizes would be required to cut all finished products without trim loss and they cannot all be inventoried. An assortment of rolls is inventoried with the implication that the sheeting operations may yield trim loss. The selection of the assortment of roll sizes to stock and the assignment of these roll sizes to finished products have a significant impact on performances. This paper presents a model to decide the parent roll assortment and assignments to finished products based on these products demand processes, desired service levels, trim loss and inventory holding costs. Risk pooling economies made by assigning several finished products to a given roll size is a fundamental aspect of the problem. The overall model is a binary non-linear program. Two solution methods are developed: a branch and price algorithm based on column generation and a fast pricing heuristic, and a marginal cost heuristic. The two methods are tested on real data and also on randomly generated problem instances. The approach proposed was implemented by a large pulp and paper company.

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.