Etude de différents impacts simultanés sur les performances environnementales et financières d une chaîne logistique

International audienceLes chaînes logistiques évoluent dans un contexte en pleine mutation où le développement durable joue un rôle crucial. Les gouvernements adoptent ou sont en train d'adopter différentes mesures concernant les gaz à effet de serre. Or, les chaînes logistiques durables manquent d'outils d'aide à la décision. Notre recherche s'intéresse donc aux émissions d'équivalent carbone dues au stockage et au transport le long d'une chaîne logistique. Nous avons développé un modèle à trois maillons grâce à la simulation à événements discrets. Trois données d'entrées sont variables : l'efficacité de l'entreprise, sa localisation et le type de produits fabriqués. Nous comparons les différents scénarios pos-sibles grâce à des critères environnementaux (émissions d'équivalent carbone) et des critères financiers (stocks, nombre de kilomètre parcourus). Les objectifs principaux sont les suivants : fournir un outil réaliste de simulation et proposer des solutions pour réduire les émissions d'équivalent carbone

Editorial: Supply networks design and management

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A simulation-based approach to assess impacts of urban logistics policies on traffic flow dynamics

International audienceIn urban environments, there are now many challenging problems concerning freight transport.As cities around the world grow rapidly, there is an increase in pickup-delivery truck traffic inurban areas. It turns out that commercial traffic is now a major source of externalities in metroareas, including congestion, noise, air pollution (small particulates, NOx, greenhouse gasemissions), and traffic incidents [1].To overcome these issues, many interesting and innovative strategies have been developed inEurope and other parts of the world. Especially, some researchers proposed the idea of citylogistics to solve these difficult problems [2-3]. The idea of this concept is to rationalize thefreight activities in cities by optimizing operations considering the traffic conditions and thecongestion issues. Consequently, public authorities strongly need decision support frameworksto evaluate urban logistics planning and management.It turns out that a key point in predicting the impacts of city logistics is the influence of freighton traffic flow dynamics. Particularly, pickup-delivery trucks maneuvers generate roadcapacity reduction and lead to delay for individual drivers. Although this is a crucial topic, theliterature rarely addresses this issue. This paper aims to fill this lack of understanding byincorporating the effects of urban freight in a traffic flow model

Contribution à la conception et au pilotage d'une entreprise réseau

http://www1.utt.fr/mosim01/pdf/ARTICLE-197.pdfInternational audienceL'évolution du contexte économique a remis en question les stratégies manufacturières des entreprises qui se sont trouvées obligées de rationaliser leurs efforts, pour consolider leurs positions sur le marché. Pour ce faire, certaines se sont regroupées en des structures en réseau rendues possibles grâce aux technologies de l'information et de la communication. La dynamique de ces architectures industrielles a intéressé des chercheurs de différentes disciplines. On se propose dans cette communication, de faire le point sur des éléments relatifs à l'étude des structures en réseau, à savoir la modélisation et les chaînes logistiques, pour s'intéresser ensuite de plus près à un modèle coopératif d'entreprise réseau, à sa configuration, sa dynamique et ses mécanismes de prise de décision

The ConWip Production Control System: a Literature Review

International audienceA growing body of literature dealing with ConWip has been observedduring the past decade. Considering the current industrial challengescharacterized by adaptability, product customization, shortened lead times andcustomer satisfaction, ConWip appears to be an effective and adaptedproduction control system for manufacturers. Given this context, this paper aimsto update the previous literature review about ConWip that was made in 2003and to provide an understanding key through an original classification method.This method allows the reader to distinguish papers that concentrate on ConWipsizing, ConWip performance, ConWip environment or on the comparison ofConWip with other PCS. It also provides a reading key about the researchapproach. Taking these criteria into account, this paper helps to answer thefollowing questions: how can ConWip be implemented? How can ConWip beoptimized? Why and when should ConWip be used? The paper then concludeswith some research avenues

Ontology-Based Approach for Application Integration

http://interop-esa05.unige.ch/INTEROP/Proceedings/Doctoral/PerPaper/II-1-Izza.pdfInternational audienceEnterprise Application Integration (EAI) is still facing the crucial semantic integration problem. This latter is not correctly addressed by today's EAI solutions that focus mainly on the technical and syntactical integration. Addressing the semantic integration level will promote EAI by providing it more consistency and robustness. Some efforts are suggested to solve the semantic integration problem, but they are still not mature. This paper deals with semantic problem in EAI and will present an ontology-based approach in order to overcome some issues of the integration problem

Resolution of Key Roles for the Distal Pocket Histidine in Cytochrome c Nitrite Reductases

Cytochrome c nitrite reductases perform a key step in the biogeochemical N-cycle by catalyzing the six-electron reduction of nitrite to ammonium. These multi-heme cytochromes contain a number of His/His ligated c-hemes for electron transfer and a structurally differentiated heme that provides the catalytic center. The catalytic heme has proximal ligation from lysine, or histidine, and an exchangeable distal ligand bound within a pocket that includes a conserved histidine. Here we describe properties of a penta-heme cytochrome c nitrite reductase in which the distal His has been substituted by Asn. The variant is unable to catalyze nitrite reduction despite retaining the ability to reduce a proposed intermediate in that process, namely, hydroxylamine. A combination of electrochemical, structural and spectroscopic studies reveals that the variant enzyme simultaneously binds nitrite and electrons at the catalytic heme. As a consequence the distal His is proposed to play a key role in orienting the nitrite for N-O bond cleavage. The electrochemical experiments also reveal that the distal His facilitates rapid nitrite binding to the catalytic heme of the native enzyme. Finally it is noted that the thermodynamic descriptions of nitrite- and electron-binding to the active site of the variant enzyme are modulated by the prevailing oxidation states of the His/His ligated hemes. This is behavior that is likely to be displayed by other multi-centered redox enzymes such that there are wide implications for considering the determinants of catalytic activity in this important and varied group of oxidoreductases

A modelling approach of pooled urban consolidation centers

International audienceCity logistics are the last link of complex supply chains which involve numerous stakeholders: carriers, inhabitants, public administration, etc. It is a small part of the total traveled distance, nevertheless it can represent up to 28% of the total transport cost [1]. Moreover, air pollution emissions related to urban freight transport is estimated between 16% and 50% of the overall pollution made by transport activities in a city [2]. Most of time, communal decision-makers do not have enough knowledge to take adapting local public policy to face these stakes [3]. As aforementioned, designing efficient transport facilitates small businesses, shops and boutiques, and therefore improve livelihood and livability of cities [4]. Hence, it is necessary to provide sustainable solutions to relieve the traffic congestion on the city center and reduce the environmental impact of urban freight transport.City logistics’ solutions available in literature [5,6] seem to be based on the use of two principles: multi-modal and pooling. Two research questions emerge. The first, how could the use of multi-modal facilities address city logistics issues? The second which is the purpose of this paper: which impact would the use of pooling concept have on urban logistics?Our approach is to develop a “What if” decision support system to provide pertinent information beforehand when designing a city logistics project. Indeed, there is a pressing need to establish models allowing ex ante assessment [7,8]

Estimer le comportement du chauffeur en milieu urbain à travers des modèles de tournées

International audienceCette communication propose une méthodologie pour estimer le comportement du chauffeur en moilieu urbain. Plus précisément, il compte construire des tournées de livraison urbaines en tenant compte de différentes logiques du chauffeur, et en les intégrant au clacul du parcours le plus proche à celui du chauffeur. Nous présentons la méthodologie générale ainsi que des résultats d'une première simulation