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Fast approximation of minimum multicast congestion – Implementation versus theory

Andreas Baltz, Anand Srivastav (2004)

RAIRO - Operations Research - Recherche Opérationnelle

The problem of minimizing the maximum edge congestion in a multicast communication network generalizes the well-known N P -hard multicommodity flow problem. We give the presently best theoretical approximation results as well as efficient implementations. In particular we show that for a network with m edges and k multicast requests, an r ( 1 + ε ) ( r t e x t O P T + exp ( 1 ) ln m ) -approximation can be computed in O ( k m ε - 2 ln k ln m ) time, where β bounds the time for computing an r -approximate minimum Steiner tree. Moreover, we present a new fast heuristic that...

Fast approximation of minimum multicast congestion – Implementation VERSUS Theory

Andreas Baltz, Anand Srivastav (2010)

RAIRO - Operations Research

The problem of minimizing the maximum edge congestion in a multicast communication network generalizes the well-known NP-hard multicommodity flow problem. We give the presently best theoretical approximation results as well as efficient implementations. In particular we show that for a network with m edges and k multicast requests, an r(1 + ε)(rOPT + exp(1)lnm)-approximation can be computed in O(kmε-2lnklnm) time, where β bounds the time for computing an r-approximate minimum Steiner tree. Moreover,...

Fast simulation for road traffic network

Roberta Jungblut-Hessel, Brigitte Plateau, William J. Stewart, Bernard Ycart (2001)

RAIRO - Operations Research - Recherche Opérationnelle

In this paper we present a method to perform fast simulation of large markovian systems. This method is based on the use of three concepts: Markov chain uniformization, event-driven dynamics, and modularity. An application of urban traffic simulation is presented to illustrate the performance of our approach.

Fast simulation for Road Traffic Network

Roberta Jungblut-Hessel, Brigitte Plateau, William J. Stewart, Bernard Ycart (2010)

RAIRO - Operations Research

In this paper we present a method to perform fast simulation of large Markovian systems. This method is based on the use of three concepts: Markov chain uniformization, event-driven dynamics, and modularity. An application of urban traffic simulation is presented to illustrate the performance of our approach.

Fault diagnosis of networked control systems

Christophe Aubrun, Dominique Sauter, Joseph Yamé (2008)

International Journal of Applied Mathematics and Computer Science

Networked Control Systems (NCSs) deal with feedback control systems with loops closed via data communication networks. Control over a network has many advantages compared with traditionally controlled systems, such as a lower implementation cost, reduced wiring, simpler installation and maintenance and higher reliability. Nevertheless, the networkinduced delay, packet dropout, asynchronous behavior and other specificities of networks will degrade the performance of closed-loop systems. In this context,...

Finding target units in FDH model by least-distance measure model

Ali Ebrahimnejad, Reza Shahverdi, Farzad Rezaee Balf, Maryam Hatefi (2013)

Kybernetika

Recently, some authors used the Least-Distance Measure model in order to obtain the shortest distance between the evaluated Decision Making Unit (DMU) and the strongly efficient production frontier. But, their model is not applicable for situation in which the production possibility set satisfies free disposability property. In this paper, we propose a new approach to this end in FDH model which improves the application potential of the Least-Distance Measure and overcomes the mentioned shortcoming....

Finite buffer GI/Geo/ 1 batch servicing queue with multiple working vacations

P. Vijaya Laxmi, Kanithi Jyothsna (2014)

RAIRO - Operations Research - Recherche Opérationnelle

This paper analyzes a discrete-time finite buffer renewal input queue with multiple working vacations where services are performed in batches of maximum size “b”. The service times both during a regular service period and vacation period and vacation times are geometrically distributed. Employing the supplementary variable and imbedded Markov chain techniques, we derive the steady-state queue length distributions at pre-arrival, arbitrary and outside observer’s observation epochs. Based on the queue...

Flexible measures in production process: A DEA-based approach

Alireza Amirteimoori, Ali Emrouznejad (2011)

RAIRO - Operations Research

Data envelopment analysis (DEA) has been proven as an excellent data-oriented efficiency analysis method for comparing decision making units (DMUs) with multiple inputs and multiple outputs. In conventional DEA, it is assumed that the status of each measure is clearly known as either input or output. However, in some situations, a performance measure can play input role for some DMUs and output role for others. Cook and Zhu [Eur. J. Oper. Res.180 (2007) 692–699] referred to these variables...

Flexible measures in production process: A DEA-based approach

Alireza Amirteimoori, Ali Emrouznejad (2011)

RAIRO - Operations Research

Data envelopment analysis (DEA) has been proven as an excellent data-oriented efficiency analysis method for comparing decision making units (DMUs) with multiple inputs and multiple outputs. In conventional DEA, it is assumed that the status of each measure is clearly known as either input or output. However, in some situations, a performance measure can play input role for some DMUs and output role for others. Cook and Zhu [Eur. J. Oper. Res.180 (2007) 692–699] referred to these variables...

Flots entiers et multiflots fractionnaires couplés par une contrainte de capacité

Alain Quilliot, Fatiha Bendali, Jean Mailfert (2005)

RAIRO - Operations Research - Recherche Opérationnelle

Nous modélisons ici plusieurs problèmes de Transport et de Gestion de Flux à l’aide d’un flot entier et d’un multiflot fractionnaire couplés par une contrainte de capacité. Pour le problème ainsi obtenu, nous proposons différents schémas de résolution par relaxation et décomposition, qui induisent la recherche d’un flot auxiliaire dont la partie entière supérieure doit minimiser un certain coût, et qui requièrent la mise en œuvre d’un processus d’agrégation. Nous en déduisons diverses heuristiques...

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