Articles scientifiques

A Queuing Framework for Routing Problems with Time-dependent Travel Times

H. Peremans, T. Van Woensel, N. Vandaele, L. KERBACHE

Journal of Mathematical Modelling and Algorithms

mars 2007, vol. 6, n°1, pp.151-173

Départements : Informations Systems and Operations Management, GREGHEC (CNRS)

Transportation is an important component of supply chain competitiveness since it plays a major role in the inbound, inter-facility, and outbound logistics. In this context, assigning and scheduling vehicle routing is a crucial management problem. Despite the existence of numerous publications dealing with efficient scheduling methods for vehicle routing, very few address the inherent stochastic nature of this problem. In this paper, a novel framework for modelling routing problems with time-dependent travel times due to potential traffic congestion is considered. The approach developed introduces mainly the traffic congestion component modelled through a queueing mode!. Standard test problems are used for illustrative purposes as well as for a discussion on the feasibility of proposed solutions if travel times are not constantKey words time-dependent routing problems - queueing - dynamic travel times

Automatic Formulation of Stochastic Programs Via an Algebraic Modeling Language

J. Thénié, C. VAN DELFT, J. Vial

Computational Management Science

janvier 2007, vol. 4, n°1, pp.17-40

Départements : Informations Systems and Operations Management, GREGHEC (CNRS)

Mots clés : Stochastic programming, Algebraic modeling language, Deterministic equivalent

This paper presents an open source tool that automatically generates the so-called deterministic equivalent in stochastic programming. The tool is based on the algebraic modeling language ampl. The user is only required to provide the deterministic version of the stochastic problem and the information on the stochastic process, either as scenarios or as a transitions-based event tree

E-Government Payoffs: Evidence from Cross- Country Data


Journal of Global Information Management

2007, vol. 15, n°4, pp.20-40

Départements : Informations Systems and Operations Management, GREGHEC (CNRS)

Mots clés : Business competitiveness, e-government, Government efficiency, IT impact, Reduction of social divide, Secondary data

Using secondary data from 99 countries and IT impact literature as the guiding theoretical perspective; we examine the payoffs from e-government in the form of national performance. We do this by initially examining the relationship of e-government development with the first order government process efficiency parameters (resource spending efficiency and administrative process efficiency). Subsequently we examine the association of these first order efficiency outcomes with the two second order dimensions of national performance (reduction of social divide and business competitiveness). Our analysis reveals significant association of ‘e-government development’ with both the first order ‘government efficiency parameters’. Further analysis reveals significant relationships of ‘government efficiency parameters’ with thedimensions of ‘national performance’. Important role of ‘national business competitiveness’ in the reduction of ‘social divide’ is brought forth through post-hoc analysis. Through this research, we make some important contributions which have implications for researchers, practitioners, public administrators, and policy makers

Facility Reliability Issues in Network p-Median Problems: Strategic Centralization and Co-location Effects

M. MENEZES, O. Berman, D. Krass

Operations Research

mars-avril 2007, vol. 55, n°2, pp.332-350

Départements : Informations Systems and Operations Management

In this paper we analyze a facility location model where facilities may be subject to disruptions, causing customers to seek service from the operating facilities. We generalize the classical p-Median problem on a network to explicitly include the failure probabilities, and analyze structural and algorithmic aspects of the resulting model. The optimal location patterns are seen to be strongly dependent on the probability of facility failure - with facilities becoming more centralized, or even co-located, as the failure probability grows. Several exact and heuristic solution approaches are developed. Extensive numerical computations are performed

Favoriser l'innovation radicale dans une entreprise multidivisionnelle. Discussion du modèle ambidextre à partir de l'analyse d'un cas

S. BEN MAHMOUD-JOUINI, F. Charue-Duboc, F. Fourcade

Finance - Contrôle - Stratégie

septembre 2007, vol. 10, n°3, pp.5-41

Départements : Informations Systems and Operations Management, GREGHEC (CNRS)

Le modèle d'organisation ambidextre constitue l'une des réponses avancées par la littérature pour développer des innovations radicales dans les grandes entreprises. Il met en avant la coexistence d'unités dédiées à l'exploration et d'autres à l'exploration et au développement de ces innovations. L'articulation de ces unités, à la fois séparées et intégrées. a été peu étudiée. Sur la. base d'une étude longitudinale d'une nouvelle unité organisationnelle créée pour favoriser l'innovation dans une grande entreprise multidivisionnelle, nous caractérisons plusieurs modes d'intégration situés à des niveaux différents ct fondés sur des mécanismes variés.


Informations Systems and Operations Management

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Vasiliki KOSTAMI

Informations Systems and Operations Management

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