124 research outputs found
Emission reduction via supply chain coordination
This paper examines the environmental impact of potential coordination on supply chains. A decentralized two-node supply chain is studied, in which one node is a buyer ordering from a second node, who is a supplier operating under the lot-for-lot policy. The supplier is allowed to use a quantity discount to manipulate the buyer's decision reducing both his individual cost and system's operational costs. This results in decreasing the frequency of deliveries. We demonstrate that environmentally friendly policies could be also cost saving. The crucial factor about the environmental benefits is the total distance travelled rather than the vehicle loads. We establish the magnitude of the environmental benefits using numerical examples under specific operational parameters. Complete and incomplete information cases are investigated, where the buyer and the supplier make their decisions to optimize their own business operations
Multicut Benders decomposition algorithm for process supply chain planning under uncertainty
Hybrid robust and stochastic optimization for closed-loop supply chain network design using accelerated Benders decomposition
Environmental Externalities Score: a new emission factor to model green vehicle routing problem
In this paper, we introduce a new emissions factor referred to as the Environmental Externalities score (EES) as a measure of transportation network factors (e.g., gradient, rolling resistance, air resistance etc.) having an impact on fuel consumption of a vehicle. We express the EES by vehicle class (i.e. light-duty and heavy-duty) as a function of each one of these factors. We base our results on extensive bibliographic research and we provide comparisons between different routing scenarios. This novel emission factor is developed to define the objective function of the green vehicle routing problem. © 2015, Springer-Verlag Berlin Heidelberg
Special volume on operational research on the interrelated application areas of energy, transportation and the environment
[No abstract available
Pilotage de production à moyen et à court terme : contribution aux problématiques d'optimisation globale vs locale et à l'ordonnancement dans les raffineries
In today's society the optimal control of medium and short term production scheduling represents a very important decision into supply chain management. In the first part of this work, we are interested in the problem of optimal control production in a medium term supply chain of two stages. The objective is to understand, in our system, what is the gain of global optimisation in contrast to local. We evaluate the behaviour of our system within two different types of optimisation (deterministic and stochastic). The models are formulated using tools from mathematical programming and from queuing theory. Many analyses are carried out, in order to define the behaviour of each model. These analyses enable a comparison between the models and help us identify the true superiority of global optimisation. In the second part, we examine the problem of short term production scheduling, which is applied in the petrochemical industry. We study the problem of scheduling the loading and unloading of tanks and the scheduling of crude oil to the refinery. The objective here is to minimise the set up cost of the tanks. We propose a general model, which takes into consideration all the different types of blending preparation and the different options of distillation of the crude oil.Le pilotage optimal de production à moyen et à court terme représente de plus en plus une décision importante pour la gestion efficace d'une chaîne logistique. Dans la première partie de ce travail, nous nous intéressons au pilotage optimal de production à moyen terme d'une chaîne logistique à deux étages. Notre objectif est de savoir quel est le bénéfice d'une optimisation globale par rapport à l'optimisation locale. Nous étudions le comportement du système pour deux types de demande (déterministe/stochastique) et par rapport aux deux types d'optimisation. La modélisation est faite à l'aide des outils de la programmation mathématique et de la théorie des files d'attente. Plusieurs analyses ont été réalisées pour pouvoir définir le comportement de chaque modèle afin de pouvoir lescomparer. Dans la deuxième partie, nous considérons le problème d'optimisation de la production à court terme appliqué à une raffinerie pétrolière. Nous nous intéressons à l'ordonnancement des activités de chargement/déchargement du pétrole brut dans les réservoirs de stockage en ayant comme objectif la minimisation du coût de reconfiguration. Nous présentons une modélisation générique qui tient compte de tous les modes de préparation de mélanges et des différentes options de distillation. Nous donnons les différentes méthodes développées pour améliorer l'efficacité de la résolution ainsi qu'une nouvelle extension sur la méthode de décomposition de Benders. Nous terminons en comparant les différentes méthodes en terme de critères de qualité de la solution obtenue et du temps de résolution
Correction to: Generic approaches for the rescheduling of public transport services (Energy Systems, (2020), 10.1007/s12667-020-00393-w)
In the original version of this article, unfortunately series of errors have been introduced during the publication process that compromise the readability of the article to considerate degree. The errors refer to presentation issues and not issues that challenge the scientific evidence provided within the article. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature
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