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Aspects of Impatience in a Finite Buffer Queue

Medhi Pallabi, Amit Choudhury (2012)

RAIRO - Operations Research

In a multi server queuing system, buffer size is often larger than the number of servers. This necessitates queuing and waiting for some customers. Customers become impatient while waiting for service. Additionally, they may also become impatient if service is not offered at the desired rate. This paper analyses a finite buffer multi server queuing system with the additional restriction that customers may balk as well as renege. Closed form expressions...

Boundedness on stochastic Petri nets.

J. Campos, F. Plo, M. San Miguel (1993)

Revista Matemática de la Universidad Complutense de Madrid

Stochastic Petri nets generalize the notion of queuing systems and are a useful model in performance evaluation of parallel and distributed systems. We give necessary and sufficient conditions for the boundedness of a stochastic process related to these nets.

Branch-and-bound algorithm for total weighted tardiness minimization on parallel machines under release dates assumptions

Imed Kacem, Nizar Souayah, Mohamed Haouari (2012)

RAIRO - Operations Research

This paper deals with the parallel-machine scheduling problem with the aim of minimizing the total (weighted) tardiness under the assumption of different release dates. This problem has been proven to be NP-hard. We introduce some new lower and upper bounds based on different approaches. We propose a branch-and-bound algorithm to solve the weighted and unweighted total tardiness. Computational experiments were performed on a large set of instances...

Branch-and-bound algorithm for total weighted tardiness minimization on parallel machines under release dates assumptions

Imed Kacem, Nizar Souayah, Mohamed Haouari (2012)

RAIRO - Operations Research

This paper deals with the parallel-machine scheduling problem with the aim of minimizing the total (weighted) tardiness under the assumption of different release dates. This problem has been proven to be NP-hard. We introduce some new lower and upper bounds based on different approaches. We propose a branch-and-bound algorithm to solve the weighted and unweighted total tardiness. Computational experiments were performed on a large set of instances...

Computational schemes for two exponential servers where the first has a finite buffer

Moshe Haviv, Rita Zlotnikov (2011)

RAIRO - Operations Research - Recherche Opérationnelle

We consider a system consisting of two not necessarily identical exponential servers having a common Poisson arrival process. Upon arrival, customers inspect the first queue and join it if it is shorter than some threshold n. Otherwise, they join the second queue. This model was dealt with, among others, by Altman et al. [Stochastic Models20 (2004) 149–172]. We first derive an explicit expression for the Laplace-Stieltjes transform of the distribution underlying the arrival (renewal) process to...

Computational schemes for two exponential servers where the first has a finite buffer

Moshe Haviv, Rita Zlotnikov (2011)

RAIRO - Operations Research

We consider a system consisting of two not necessarily identical exponential servers having a common Poisson arrival process. Upon arrival, customers inspect the first queue and join it if it is shorter than some threshold n. Otherwise, they join the second queue. This model was dealt with, among others, by Altman et al. [Stochastic Models20 (2004) 149–172]. We first derive an explicit expression for the Laplace-Stieltjes transform of the distribution underlying the arrival (renewal) process to...

Finite time asymptotics of fluid and ruin models: multiplexed fractional Brownian motions case

Krzysztof Dębicki, Grzegorz Sikora (2011)

Applicationes Mathematicae

Motivated by applications in queueing fluid models and ruin theory, we analyze the asymptotics of ( s u p t [ 0 , T ] ( i = 1 n λ i B H i ( t ) - c t ) > u ) , where B H i ( t ) : t 0 , i = 1,...,n, are independent fractional Brownian motions with Hurst parameters H i ( 0 , 1 ] and λ₁,...,λₙ > 0. The asymptotics takes one of three different qualitative forms, depending on the value of m i n i = 1 , . . . , n H i .

How to eliminate non-positive circuits in periodic scheduling: a proactive strategy based on shortest path equations

Sid-Ahmed-Ali Touati, Sébastien Briais, Karine Deschinkel (2013)

RAIRO - Operations Research - Recherche Opérationnelle

Usual periodic scheduling problems deal with precedence constraints having non-negative latencies. This seems a natural way for modelling scheduling problems, since task delays are generally non-negative quantities. However, in some cases, we need to consider edges latencies that do not only model task latencies, but model other precedence constraints. For instance in register optimisation problems devoted to optimising compilation, a generic machine or processor model can allow considering access...

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