Guillaume Marquès

A review of Vendor Managed Inventory (VMI): from concept to processes

In the modern supplier–customer relationship, Vendor Managed Inventory (VMI) is used to monitor the customers inventory replenishment. Despite the large amount of literature on the subject, it is difficult to clearly define VMI and the main associated processes. Beyond the short-term pull system inventory replenishment often studied in academic works, partners have to share their vision of the demand, their requirements and their constraints in order to fix shared objectives for the medium/long-term. In other words, the integration of VMI implies consequences for the collaborative process that links each partners different planning processes. In this article we propose a literature review of VMI. Based on the conceptual elements extracted from this analysis, we suggest a VMI macro-process that summarises both operational and collaborative elements of VMI.

Decision support system for servitization of industrial SMEs: a modelling and simulation approach

Industry servitisation, i.e. the manufacturing industry transition towards the integration of services, provides for strong opportunities of new business model development and implementation. However, managing the industrial transformation to such business models means decision-makers are confronted with high decisional complexity. Such dramatic changes affect most enterprise performance drivers, and the interactions of the multiple business and industrial factors influencing the overall company performance make it very difficult for managers to specify consistent and efficient industrial configurations for their business processes. This context explains a concrete need for developing servitisation-dedicated decision support systems (DSS). The objective of the decision aid developed in this paper is to provide operational support which integrates the specific business and industrial features of so-called ‘product–service systems’ in order to study the interactions of different types of performance factors, notably market-oriented versus industrial-oriented factors. These developments are applied to a French Small and Medium Enterprise (SME). The key added values of the paper are (1) to specify a modelling and simulation approach associated to a generic simulator adaptable to various industrial contexts, then (2) to illustrate the concrete decision support provided in a case study of an SME in the business of remanufacturing electrical equipment. The case study highlights capacity management issues in a servitisation context.

How to anticipate the level of activity of a sustainable collaborative network: The case of urban freight delivery through logistics platforms

In this paper, we elaborate a methodology to study a particular case of collaborative network: city logistics. We identify that many solutions for urban logistics are, most of time, badly evaluated. Indeed, the theory often predicts a positive effect but the reality is most of time counterbalanced. We tried to fill this gap by making use of innovative methods. To do so, we mobilize several domains of knowledge: operational research, game theory and transportation studies on real cases. We suggest a solution to anticipate the level of activity of an Urban Consolidation Center and determine the condition under which it generates benefit for a carrier using or not, the collaborative network. We present the result obtained by application of our method on the real case of the city of Saint-Etienne.

Managing transition towards PSS: a production system simulation approach

The transition of manufacturing companies towards Product Service System (PSS) offers was mainly treated in the literature at the strategic level. This paper aims at studying the impact of the transition in operation management, with a specific focus on capacity management. With this purpose we present below a PSS Production System, used as a decision support tool. We first explain conceptually the modelling approach used, and the general concepts. Then we explain how discrete events simulation was applied to study different scenarios and strategy of capacity management on a case study. First results of this feasibility study are discussed.

PSS Production Systems: a simulation approach for change management

The research presented in this paper is oriented on the transition of the manufacturing industry towards the delivery of product-service system. The paper presents the first results in the development of a decision support system dedicated to help in configuring service-oriented production systems, notably with an objective of capacity management. An illustrative case study is presented, linked to the production of washing machines.

RTLS-based Process Mining: Towards an automatic process diagnosis in healthcare

Log files constitute the main data source required to be able to use a Process Mining tool. As soon as an information system enables to record events corresponding to activity changes, it is rather simple and rapid to completely and automatically model a process. In numerous fields, information systems do not record events enough detailed. Therefore the model obtained with Process Mining will not be accurate and detailed enough for further analysis. In this article, we are interested in modeling with Process Mining patient pathways in an external consulting service of a hospital center. Apart from recording patients at the front desk and when they are leaving, the information system does not collect enough events in order to manage to model in details the different patient pathways. As a result, the model must be realised with successive observations, interviews and manual collects. This work often represents a significant workload without ensuring data quality and representativeness. To resolve this issue we suggest using a Real Time Location System (RTLS) that enables to automatically record events according to patient locations in the service. The log file obtained can contain the pathway tracks followed by the patients with enough details to precisely rebuild the process with Process Mining. This article is intended for users, for diagnosis experts who will be able to realise an accurate diagnosis and then propose improvements. This article deals with our on-going work through a real case study.

Decision support with ill-known criteria in the collaborative supply chain context

In the field of Supply Chain Risk Management, the attitude of managers toward risk affect the tactical decision-making process in collaborative supply chains under an uncertain environment, concerning especially capacity levels, lot-sizing rules, purchasing strategies, production scheduling,?, etc. The issue can be formulated as a sequential decision problem under uncertainty where the customer decisions affect the decisions made by the supplier. In this paper we deal with two kinds of uncertainties. The first one is the uncertainty on the indicators of performance (which are not comparable) used by the decision maker to choose a solution (for example: service quality or inventory cost). Hence, we propose an approach based on subjective probability to evaluate the probability that a decision is optimal for the first actor and the probability that it is optimal for both. From these two evaluations, we propose a ranking function to help the first actor to take into account the second one when selecting a decision. The second kind of uncertainty pertains to the demand. A classical criterion under total uncertainty is Hurwicz criterion where a weight expresses a degree of pessimism. Nevertheless, the degree of pessimism is itself ill-known. Thus, it becomes difficult to take into account the behavior of the actors. Hence, we propose an approach based on possibility theory and the so-called pignistic transform, which computes a subjective probability distribution over the criteria. Then, we apply the method used for uncertain criterion. This approach is illustrated through an example and an industrial case study.