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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...

Flots entiers et multiflots fractionnaires couplés par une contrainte de capacité

Alain Quilliot, Fatiha Bendali, Jean Mailfert (2006)

RAIRO - Operations Research

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...

Flow control in connection-oriented networks: a time-varying sampling period system case study

Przemysław Ignaciuk, Andrzej Bartoszewicz (2008)

Kybernetika

In this paper congestion control problem in connection-oriented communication network with multiple data sources is addressed. In the considered network the feedback necessary for the flow regulation is provided by means of management units, which are sent by each source once every M data packets. The management units, carrying the information about the current network state, return to their origin round trip time RTT after they were sent. Since the source rate is adjusted only at the instant of...

Flow Polyhedra and Resource Constrained Project Scheduling Problems

Alain Quilliot, Hélène Toussaint (2012)

RAIRO - Operations Research - Recherche Opérationnelle

This paper aims at describing the way Flow machinery may be used in order to deal with Resource Constrained Project Scheduling Problems (RCPSP). In order to do it, it first introduces the Timed Flow Polyhedron related to a RCPSP instance. Next it states several structural results related to connectivity and to cut management. It keeps on with a description of the way this framework gives rise to a generic Insertion operator, which enables programmers to design greedy and local search algorithms....

Forecast horizon and planning horizon paths in time-indexed network

Stanisław Bylka (2006)

Banach Center Publications

The problem of existence of a forecast (or planning) horizon has been considered in many special models, more or less precisely. We specify and investigate this problem for families of cheapest paths in networks with weakly ordered nodes. In a discrete network, the standard forward algorithm finds the subnetwork generated by optimal paths. The proposed forward procedure reduces subnetworks such that the forecast horizon remains unchanged. Based on the final subnetwork, we have an answer to the forecast...

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