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Optimal QoS control of interacting service stations

Abdelkrim Haqiq, I. Lambadaris, N. Mikou, L. Orozco-Barbosa (2002)

RAIRO - Operations Research - Recherche Opérationnelle

We consider a system of three queues and two types of packets. Each packet arriving at this system finds in front of it a controller who either sends it in the first queue or rejects it according to a QoS criterion. When the packet finishes its service in the first queue, it is probabilistically routed to one of two other parallel queues. The objective is to minimize a QoS discounted cost over an infinite horizon. The cost function is composed of a waiting cost per packet in each queue and a rejection...

Optimal QoS control of interacting service stations

Abdelkrim Haqiq, I. Lambadaris, N. Mikou, L. Orozco–Barbosa (2010)

RAIRO - Operations Research

We consider a system of three queues and two types of packets. Each packet arriving at this system finds in front of it a controller who either sends it in the first queue or rejects it according to a QoS criterion. When the packet finishes its service in the first queue, it is probabilistically routed to one of two other parallel queues. The objective is to minimize a QoS discounted cost over an infinite horizon. The cost function is composed of a waiting cost per packet in each queue and a rejection...

Optimal transportation networks as free Dirichlet regions for the Monge-Kantorovich problem

Giuseppe Buttazzo, Eugene Stepanov (2003)

Annali della Scuola Normale Superiore di Pisa - Classe di Scienze

In the paper the problem of constructing an optimal urban transportation network in a city with given densities of population and of workplaces is studied. The network is modeled by a closed connected set of assigned length, while the optimality condition consists in minimizing the Monge-Kantorovich functional representing the total transportation cost. The cost of trasporting a unit mass between two points is assumed to be proportional to the distance between them when the transportation is carried...

Optimization of power transmission systems using a multi-level decomposition approach

Alexandre Dolgui, Nikolai Guschinsky, Genrikh Levin (2007)

RAIRO - Operations Research

We discuss the use of operations research methods for computer-aided design of mechanical transmission systems. We consider how to choose simultaneously transmission ratios and basic design parameters of transmission elements (diameters, widths, modules and tooth number for gears, diameters of shafts). The objectives, by the order of importance, are: to minimize the deviation of the obtained speeds from desired; to maximize the transmission life; to minimize the total mass. To solve this...

Parallélisation d'une Combinaison des Méthodes de Monte-Carlo et Quasi-Monte-Carlo et Application aux Réseaux de Files d'Attente

Bruno Tuffin, Louis-Marie Le Ny (2010)

RAIRO - Operations Research

We propose a parallel algorithm which uses both Monte-Carlo and quasi-Monte-Carlo methods. A detailed analysis of this algorithm, followed by examples, shows that the estimator's efficiency is a linear function of the processor number. As a concrete application example, we evaluate performance measures of a multi-class queueing network in steady state.

Path functionals over Wasserstein spaces

Alessio Brancolini, Giuseppe Buttazzo, Filippo Santambrogio (2006)

Journal of the European Mathematical Society

Given a metric space X we consider a general class of functionals which measure the cost of a path in X joining two given points x 0 and x 1 , providing abstract existence results for optimal paths. The results are then applied to the case when X is aWasserstein space of probabilities on a given set Ω and the cost of a path depends on the value of classical functionals over measures. Conditions for linking arbitrary extremal measures μ 0 and μ 1 by means of finite cost paths are given.

Separable convexification and DCA techniques for capacity and flow assignment problems

P. Mahey, Thai Q. Phong, H. P. L. Luna (2001)

RAIRO - Operations Research - Recherche Opérationnelle

We study a continuous version of the capacity and flow assignment problem (CFA) where the design cost is combined with an average delay measure to yield a non convex objective function coupled with multicommodity flow constraints. A separable convexification of each arc cost function is proposed to obtain approximate feasible solutions within easily computable gaps from optimality. On the other hand, DC (difference of convex functions) programming can be used to compute accurate upper bounds and...

Separable convexification and DCA techniques for capacity and flow assignment problems

P. Mahey, Thai Q. Phong, H. P.L. Luna (2010)

RAIRO - Operations Research

We study a continuous version of the capacity and flow assignment problem (CFA) where the design cost is combined with an average delay measure to yield a non convex objective function coupled with multicommodity flow constraints. A separable convexification of each arc cost function is proposed to obtain approximate feasible solutions within easily computable gaps from optimality. On the other hand, DC (difference of convex functions) programming can be used to compute accurate upper bounds and...

Currently displaying 101 – 120 of 146