This thesis attempts to integrate the three supplier processes- supplier segmentation, supplier selection/evaluation and order allocation- based on a case study of a white goods manufacturer. These processes are dealt with in a hierarchical manner, where the decisions at an earlier stage (supplier segmentation) may affect on the results of later stages (supplier selection/evaluation and order allocation). Based on a wide set of variables gathered from the supplier segmentation literature and from the framework developed by the case company, a factor analysis is performed. The resulting eight factors (complexity and criticality, supply market dynamism, supplier&rsquo / s economic dependence, buyer&rsquo / s supplier dependence, uncertainty, supplier capabilities, supplier&rsquo / s specialization to white goods manufacturer and possibility of harm to user) are used for clustering analysis with the K-means method. Three different clustering schemes (4-clusters, 8-clusters, and 18-clusters) are analyzed to see the effect of number of clusters on the cluster means. A supplier selection model is constructed by the PROMETHEE method as was done in a former study at the same company. Two different scenarios are considered in the supplier selection phase: First, data from the former study are kept as they are. The second scenario considers a change of criteria weights. As a result, the qualified suppliers were found to be the same in both scenarios, but the rankings and net flows, which were inputs to the order allocation model, changed. The effects of these changes were discussed at a conceptual level, due to a lack of case data for the order allocation model.

This master´s thesis deals with the management of the purchasing strategy in the selected business company. This company sells products to final customers. The purpose of the thesis is to monitor purchasing processes mainly focusing on the supplier selection process. Thesis contains suggestion for a systematic selection process of prospective business partners, which is divided into four phases. Proposed suggestion contributes to higher productivity of the company´s purchasing strategy and considerably eliminates risk of high dependence on the sole supplier.

The diploma thesis decsribes the company purchasing processes. The thesis is focusing on the company purchasing functions. It defines the working methods and the processes through which the purchasing processes are coordinated. The target is to describe the complexity of the system and its complete structure. The theoretical part presents theoretical solutions to the problems related to absence of the strategic purchasing in the company. It describes the missing processes and suggests how to implement the strategic sourcing department. The practical part is focusing on presenting the solution to problems related to material procuring based on the company financial analysis. The goal is to implement missing processes in the company organization a to focus on the supplier selection and the supplier development as the key purchasing problem. The diploma thesis describes the purchasing system in its complexity. The thesis is structurized to describe every single function and process ensuring that the material procurement works effectively and efficiently.

La libéralisation des échanges, le développement des moyens de transport de marchandises à faible coût et l’essor économique des pays émergents font de la globalisation (mondialisation) des chaînes logistiques un phénomène irréversible. Si ces chaines globalisées permettent de réduire les coûts, en contrepartie, elles multiplient les risques de rupture depuis la phase d’approvisionnement jusqu’à la phase finale de distribution. Dans cette thèse, nous nous focalisons sur la phase amont. Nous traitons plus spécifiquement le cas d’une centrale d’achat devant sélectionner des fournisseurs et allouer les commandes aux fournisseurs retenus. Chacun des fournisseurs risque de ne pas livrer ses commandes pour des raisons qui lui sont propres (problèmes internes, mauvaise qualité) ou externes (catastrophe naturelle, problèmes de transport). Selon que les fournisseurs sélectionnés livrent ou non leurs commandes, l’opération dégagera un profit ou sera déficitaire. L’objectif de cette thèse, est de fournir des outils d’aide à la décision à un décideur confronté à ce problème tout en prenant en compte le comportement du dit décideur face au risque. Des programmes stochastiques en nombre entiers mixtes ont été proposés pour modéliser ce problème. La première partie du travail porte sur l’élaboration d’un outil visuel d’aide à la décision permettant à un décideur de trouver une solution maximisant le profit espéré pour un risque de perte fixé. La deuxième partie applique les techniques d’estimation et de quantification du risque VAR et CVaR à ce problème. L’objectif est d’aider un décideur qui vise à minimiser la valeur de l’espérance du coût (utilisation de VaR) ou à minimiser la valeur de l’espérance du coût dans le pire des cas (utilisation de VAR et CVaR). Selon nos résultats, il apparaît que le décideur doit prendre en compte les différents scénarios possibles quelque soit leurs probabilités de réalisation, pour que la décision soit efficace. / Trade liberalization, the development of mean of transport and the development economic of emerging countries which lead to globalization of supply chain is irreversible phenomen. They can reduce costs, in return, they multiply the risk of disruption from upstream stage to downstream stage. In this thesis, we focus on the inbound supply chain stage. We treat more specifically the case of a purchasing central to select suppliers and allocate the orders. Each of the suppliers cannot deliver its orders due to internal reasons (poor quality problems) or external reasons (natural disasters, transport problems). According to the selected suppliers deliver their orders or not, the transaction operation will generate a profit or loss. The objective of this thesis is to provide decision support tools to a decision maker faced with this problem by taking into account the behavior of decision maker toward risk. We proposed stochastic mixed integer linear programs to model this problem. In the first part, we focuses on the development of a decision support visual tool that allows a decision maker to find a compromise between maximizing the expected profit and minimize the risk of loss. In the second part, we integrated the techniques of estimation of risk VaR and CVaR in this problem. The objective is to help decision maker to minimize the expected cost and minimize the conditional value at risk simultanously via calculating of VaR. Result shows that the decision maker must tack into account the different scenarios of disruption regardless their probability of realisation.