Person:
Artalejo Rodríguez, Jesús Manuel

First Name

Jesús Manuel

Last Name

Artalejo Rodríguez

URI

https://hdl.handle.net/20.500.14352/82709

Affiliation

Universidad Complutense de Madrid

Faculty / Institute

Ciencias Matemáticas

Area

Estadística e Investigación Operativa

Identifiers

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Now showing 1 - 10 of 89

Analysis of Markov multiserver retrial queues with negative arrivals
(Queueing Systems, 2001) Artalejo Rodríguez, Jesús Manuel; Anisimov, Vladimir V.
Negative arrivals are used as a control mechanism in many telecommunication and computer networks. In the paper we analyze multiserver retrial queues; i.e., any customer finding all servers busy upon arrival must leave the service area and re-apply for service after some random time. The control mechanism is such that, whenever the service facility is full occupied, an exponential timer is activated. If the timer expires and the service facility remains full, then a random batch of customers, which are stored at the retrial pool, are automatically removed. This model extends the existing literature, which only deals with a single server case and individual removals. Two different approaches are considered. For the stable case, the matrix–analytic formalism is used to study the joint distribution of the service facility and the retrial pool. The approximation by more simple infinite retrial model is also proved. In the overloading case we study the transient behaviour of the trajectory of the suitably normalized retrial queue and the long-run behaviour of the number of busy servers. The method of investigation in this case is based on the averaging principle for switching processes.
Stationary analysis of a retrial queue with preemptive repeated attempts
(Operations Research Letters, 2001) Artalejo Rodríguez, Jesús Manuel; Dudin, Alexander N.; Klimenok, Valentina, I.
We consider a retrial queueing system where customers at the retrial group have preemptive priority over customers at the waiting line. The stationary distribution can be approximated at a desired level of accuracy in such a way that the approximated marginal distribution of the number of customers at the retrial group remains equal to the exact marginal distribution.
On the distribution of the successful and blocked events in the M/M/c retrial queue: A computational approach
(Applied Mathematics and Computation, 2007) Artalejo Rodríguez, Jesús Manuel; Amador Pacheco, Julia
This paper deals with the main retrial queue of M/M/c-type with exponential repeated attempts. We refer to a busy period and present a detailed computational analysis of four new performance measures: (i) the successful retrials, (ii) the blocked retrials, (iii) the successful primary arrivals, and (iv) the blocked primary arrivals.
The SIS and SIR stochastic epidemic models: A maximum entropy approach
(Theoretical population biology, 2011) Artalejo Rodríguez, Jesús Manuel; López Herrero, María Jesús
We analyze the dynamics of infectious disease spread by formulating the maximum entropy (ME) solutions of the susceptible-infected-susceptible (SIS) and the susceptible-infected-removed (SIR) stochastic models. Several scenarios providing helpful insight into the use of the ME formalism for epidemic modeling are identified. The ME results are illustrated with respect to several descriptors, including the number of recovered individuals and the time to extinction. An application to infectious data from outbreaks of extended spectrum beta lactamase (ESBL) in a hospital is also considered.
Stochastic epidemic models: new behavioral indicators of the disease spreading
(Applied Mathematical Modelling, 2014) Artalejo Rodríguez, Jesús Manuel; López Herrero, María Jesús
The purpose of this paper is to propose new indicators of the dynamics of infectious disease spread in stochastic epidemic models, including both global system-oriented descriptors (e.g. the final size measured as the number of individuals infected on a least one occasion during an outbreak) and individual-oriented descriptors (e.g. the time to reach an individual run of infections). We focus on birth-and-death models and the basic SIR epidemic model but the methodology remains valid for other nonlinear stochastic epidemic models. The theory is illustrated by numerical experiments which demonstrate that the proposed behavioral indicators can be applied efficiently
Some results on the M/G/1 queue with N-policy
(Asia-Pacific Journal of Operational Research, 1998) Artalejo Rodríguez, Jesús Manuel
This paper deals with the M/G/1 queue with N-policy. We show some applications of the stochastic decomposition property for the queue size. A new stochastic decomposition property for the waiting time is observed. Explicit expressions for the moments of the stationary waiting time are also obtained.
On the single server retrial queue with balking
(INFOR. Information systems and operational research, 2000) Artalejo Rodríguez, Jesús Manuel; López Herrero, María Jesús
We are concerned with the M/G/1 retrial queue with balking. The ergodicity condition is first investigated making use Of classical mean drift criteria. The limiting distribution of the number of customers in the system is determined with the help of a recursive approach based on the theory of regenerative processes. Many closed form expressions are obtained when we reduce to the M/M/1 queue for some representative balking policies.
Algorithmic analysis of the maximum queue length in a busy period for the M/M/c retrial queue
(INFORMS Journal on Computing, 2007) Artalejo Rodríguez, Jesús Manuel; Economou, A.; López Herrero, María Jesús
This paper deals with the maximum number of customers in orbit (and in the system) during a busy period for the M/M/c retrial queue. Determining the distribution for the maximum number of customers in orbit is reduced to computation of certain absorption probabilities. By reducing to the single-server case we arrive at a closed analytic formula. For the multi-server case we develop an efficient algorithmic procedure for computation of this distribution by exploiting the special block-tridiagonal structure of the system. Numerical results illustrate the efficiency of the method and reveal interesting facts concerning the behavior of the M/M/c retrial queue.
Accessible bibliography on retrial queues: Progress in 2000–2009
(Mathematical and Computer Modelling, 2010) Artalejo Rodríguez, Jesús Manuel
In this work, we present a bibliography on retrial queues which updates the bibliography published in this journal in Artalejo (1999) [7]. The bibliography is focused on the progress made during the last decade 2000–2009. For the sake of completeness, a few papers published in 1999, and non-cited in Artalejo (1999) [7], have also been included. To keep the length manageable we have excluded conference proceedings, theses, unpublished reports, and works in languages other than English.
Low retrial analysis of multiserver queues with repeated attempts due to impatience
(Simulation in Industry´2000, 2000) Artalejo Rodríguez, Jesús Manuel; López Herrero, María Jesús; Moller, DPF
We consider a multiserver queueing system where customers may become impatient and then retry for service after some random time. The study of this queueing model is motivated by the existence of exchange distributed operating systems with a time-out mechanism (Boyer et al. 1988). In this paper, we concentrate on the system performance under low retrial rate.