Development of flow optimization models in reverse logistics : Application to refillable containers

Dans un monde industriel marqué par un contexte économique difficile, les entreprises se doivent d’étudier toutes les possibilités de réduction de coûts et d’optimisation de leur chaîne logistique. Un des champs récents d’optimisation développé dans la littérature concerne le concept de logistique inverse. Cette logistique représente la gestion des flux traversant une chaîne logistique dans le sens inverse des flux traditionnels. On y retrouve des activités liées au recyclage, à la réparation ou encore à la réutilisation de produits. Au sein de la Chaire Supply Chain, nous nous sommes donc intéressés à l’optimisation de la gestion de ces flux de retours, avec les contenants réutilisables comme objet d’étude intéressant pour nos différents partenaires. Dans ce sens, après avoir passé en revue la littérature sur le concept général de la logistique inverse, nous développons un ensemble de modèles recouvrant les combinaisons mono ou multi niveaux, mono ou multi périodes et mono ou multi contenants afin d’optimiser ces retours au sein de chaînes logistiques déjà définies. Ces modèles sont par la suite appliqués, soit fictivement pour un des modèles mono-période résolu grâce à une heuristique de décomposition développée pour des réseaux logistiques de grande taille, soit réellement chez nos partenaires pour les modèles multi-périodes résolus de façon exacte. Le but de ces applications étant d’utiliser ces modèles théoriques dans un contexte réel d’entreprise et d’en dégager les possibles bénéfices économiques mais également environnementaux grâce à la prise en compte des émissions liées au transport et au cycle de vie de ces contenants.In an industrial world touched by a complicated economic environment, companies need to explore all opportunities for cost reduction and supply chain optimization. A recent optimization field developed in the literature concerns the concept of reverse logistics. This concept deals with the flows management through a supply chain in the opposite direction to the traditional one. It includes activities related to recycling, repair or products reuse. In partnership with the industrial of the “Chaire Supply Chain”, we are interested in optimizing these reverse flows by focusing more particularly on reusable containers. For that, we propose a literature review on the general concept of reverse logistics and develop a set of models covering combinations between single and multi-levels, single and multi-periods and single and multi-containers problems in order to optimize this type of returns within already defined supply chains. These models are then applied, either in a fictive way for a single-period one solved by a decomposition heuristic proposed for large logistics networks, or in a real way for multi-period models solved exactly and applied to our partners problematic. The purpose of these applications is to use these theoretical models in a real business in order to identify economic benefits but also environmental ones by taking into account emissions from these containers transportation and manufacturing

Développement de modèles d'optimisation de flux en logistique inverse (Applications aux contenants réutilisables)

Dans un monde industriel marqué par un contexte économique difficile, les entreprises se doivent d étudier toutes les possibilités de réduction de coûts et d optimisation de leur chaîne logistique. Un des champs récents d optimisation développé dans la littérature concerne le concept de logistique inverse. Cette logistique représente la gestion des flux traversant une chaîne logistique dans le sens inverse des flux traditionnels. On y retrouve des activités liées au recyclage, à la réparation ou encore à la réutilisation de produits. Au sein de la Chaire Supply Chain, nous nous sommes donc intéressés à l optimisation de la gestion de ces flux de retours, avec les contenants réutilisables comme objet d étude intéressant pour nos différents partenaires. Dans ce sens, après avoir passé en revue la littérature sur le concept général de la logistique inverse, nous développons un ensemble de modèles recouvrant les combinaisons mono ou multi niveaux, mono ou multi périodes et mono ou multi contenants afin d optimiser ces retours au sein de chaînes logistiques déjà définies. Ces modèles sont par la suite appliqués, soit fictivement pour un des modèles mono-période résolu grâce à une heuristique de décomposition développée pour des réseaux logistiques de grande taille, soit réellement chez nos partenaires pour les modèles multi-périodes résolus de façon exacte. Le but de ces applications étant d utiliser ces modèles théoriques dans un contexte réel d entreprise et d en dégager les possibles bénéfices économiques mais également environnementaux grâce à la prise en compte des émissions liées au transport et au cycle de vie de ces contenants.In an industrial world touched by a complicated economic environment, companies need to explore all opportunities for cost reduction and supply chain optimization. A recent optimization field developed in the literature concerns the concept of reverse logistics. This concept deals with the flows management through a supply chain in the opposite direction to the traditional one. It includes activities related to recycling, repair or products reuse. In partnership with the industrial of the Chaire Supply Chain , we are interested in optimizing these reverse flows by focusing more particularly on reusable containers. For that, we propose a literature review on the general concept of reverse logistics and develop a set of models covering combinations between single and multi-levels, single and multi-periods and single and multi-containers problems in order to optimize this type of returns within already defined supply chains. These models are then applied, either in a fictive way for a single-period one solved by a decomposition heuristic proposed for large logistics networks, or in a real way for multi-period models solved exactly and applied to our partners problematic. The purpose of these applications is to use these theoretical models in a real business in order to identify economic benefits but also environmental ones by taking into account emissions from these containers transportation and manufacturing.CHATENAY MALABRY-Ecole centrale (920192301) / SudocSudocFranceF

Reverse Logistics Optimization : Application to Reusable Containers

International audienceReverse Logistics is now considered as an interesting source of economies in supply chain management. Through different activities, this logistics has received increasing attention from researchers and practitioners. In this paper, we are interested in a tactical problem by focusing on the optimization of return flows of reusable containers, while considering an existing network. This situation is very encountered by third part logistics companies. The optimization model we propose is a MILP which minimizes the total cost of these return flows. In order to be realistic, we want to use this model on large size networks. The key point is the computation time which exponentially increases with the size of the problem. A simple heuristic is also proposed in order to reduce this computational time. Finally, a numerical experiment is presented to demonstrate the performance of the developed model as well as the efficiency of the proposed heuristic

Reusable Containers Management: From a Generic Model to an Industrial Case Study

International audienceIn recent years, the management of product return flows traditionally called reverse logistics has received increasing attention from the academic and business worlds. Indeed, the industrial world is more and more concerned with the environmental and economic benefits of such a type of logistics. Nevertheless, the maturity levels on these returns management strongly differ from one company to another. The aim of this work is thus to develop a generic model for reverse logistics management focused on reusable containers. This generic model should be adaptable to the specific requirements of a company (logistics network design, containers management rules, etc.). After positioning the problem within the literature and explaining the approach, we briefly describe the developed generic model. Then, we focus on a precise and real-life industrial application at a luxury goods company, describing their problem, the tailored model, as well as the results obtained from economic and environmental points of view

Reusable transportation items management: A case study

International audienceThe management of product return flows, traditionally called reverse logistics, has received more and more attention from researchers and practitioners, because of the possible environmental and economic benefits highlighted in some studies of recent years. Another reason could also be an obligation of new legislation like for electronic and electrical waste management. Nevertheless, the maturity levels on these returns management strongly differ from one company to another. That is why, in this paper, we propose a notation system to classify different types of reverse logistics, particularly for reused products. Each notation so related to a generic model, developed and proposed to practitioners. These generic models should be adaptable to the specific requirements of a company (logistics network design, products management policies ...). After positioning the problem within the literature and explaining the approach, we describe the notation system proposed. Then, we focus on a real industrial application at a food company, describing their problematic, the tailored model as well as some smart logistics remarks to improve the results obtained

Outer membrane vesicles are vehicles for the delivery of Vibrio tasmaniensis virulence factors to oyster immune cells

Vibrio tasmaniensis LGP32, a facultative intracellular pathogen of oyster haemocytes, was shown here to release outer membrane vesicles (OMVs) both in the extracellular milieu and inside haemocytes. Intracellular release of OMVs occurred inside phagosomes of intact haemocytes having phagocytosed few vibrios as well as in damaged haemocytes containing large vacuoles heavily loaded with LGP32. The OMV proteome of LGP32 was shown to be rich in hydrolases (25%) including potential virulence factors such as proteases, lipases, phospholipases, haemolysins and nucleases. One major caseinase/gelatinase named Vsp for vesicular serine protease was found to be specifically secreted through OMVs in which it is enclosed. Vsp was shown to participate in the virulence phenotype of LGP32 in oyster experimental infections. Finally, OMVs were highly protective against antimicrobial peptides, increasing the minimal inhibitory concentration of polymyxin B by 16-fold. Protection was conferred by OMV titration of polymyxin B but did not depend on the activity of Vsp or another OMV-associated protease. Altogether, our results show that OMVs contribute to the pathogenesis of LGP32, being able to deliver virulence factors to host immune cells and conferring protection against antimicrobial peptides