JEAN-MARIE , Alain

We present the marmoteCore software project, an open environment for modeling with Markov chains. This platform aims at providing the general scientific user with tools for creating Markov models and accessing the many solution algorithms available for their analysis. We describe its object-oriented architecture, some of its presently available...

This paper is concerned with load balancing in Omega-like networks. A variation of the Mitra-Cieslak random re-routing algorithm is considered. The global aim of the paper is to analyze the cost of the resequencing algorithm that has to be implemented in order to cope with possible message overtaking due to re-routing. Analytical expressions...

We consider a system of two independent servers in parallel. The arriving customers can be directed to either of the two waiting lines. We suppose that there are several classes of customers, routed according to Bernoulli process (with rates depending on class only), and that they have to be resequenced before leaving the system. We determine...

We consider systems with Poisson arrivals and a deterministic delay structure given by some increasing sequence. We characterize the distribution of waiting times in the transient regime, and describe effective ways to evaluate it. We also compute the stationary waiting time distribution in the case where the deterministic structure becomes...

In this paper, we consider a singular control optimization problem which generalizes the Gordon–Schaefer model. A population of individuals with endogenous growth is harvested by two independent agents, and their joint profit is maximized. We show that adding a second control to the standard model greatly complicates the standard solution,...

Modeling the amount of solar energy received by a photovoltaic panel is an essential part of Green IT research. The specific motivation of this work is the management of the energy consumption of large datacenters. We propose a new stochastic model for the solar irradiance, featuring minute-scale variations and therefore suitable for short-term...

We consider a single server queue in continuous time, in which customers must beserved before some limit sojourn time of exponential distribution. A customer who is not servedbefore this limit leaves the system: it is impatient. The fact of serving customers and the fact oflosing them due to impatience induce costs. The fact of holding them in...

The nature of fishing activities is such that marine habitats can be deteriorated when employing destructive fishing gear. This makes even more complex the determination of sustainable fishing policies and has led some authors to propose dynamic models which take into account this habitat degradation. In this work, we analyze in detail one of...

We consider a single server queue in continuous time, in which customers must be served before some limit sojourn time of exponential distribution. Customers who are not served before this limit leave the system: they are impatient. The fact of serving customers and the fact of losing them due to impatience induce costs. The fact of holding...

In this paper, we introduce a new accumulation process, the Semi-Markov Accumulation Process (SMAP). This class of processes extends the framework of continuous-time Markov Additive Processes (MAPs) by allowing the underlying environmental component to be a semi-Markov process instead of a Markov process. Next, we follow an analytic approach to...

The tutorial provides an introduction to the capabilities of software environment Marmotevia its Python interface: pyMarmote/pyMarmoteMDP.Marmote is a programming library for modeling with Markov chains, analyzing and "solving" these chains. It provides the objects for building continuous-time and discrete-timeMarkov chains on discrete but...

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The main property of a (hard) real-time system is feasibility. It is the guarantee that tasks do always meet their deadlines, when the system is running under a given scheduling policy. An optimal policy produces a feasible schedule whenever a feasible schedule exists. It is therefore the most appropriate choice if feasibility is the only...

We consider a single server queue in discrete time, in which customers must be served before some limit sojourn time of geometrical distribution. A customer who is not served before this limit leaves the system: it is impatient. The fact of serving customers and the fact of losing them due to impatience induce costs. The purpose is to decide...

Parallelism in the download process of large files is an efficient mechanism for distributed systems. In such systems, some peers (clients) exploit the power of parallelism to download blocks of data stored in a distributed way over some other peers (servers). Determining response times in parallel downloading with capacity constraints on both...

Parallelism in the download process of large files is an efficient mechanism for distributed systems. In such systems, some peers (clients) exploit the power of parallelism to download blocks of data stored in a distributed way over some other peers (servers). Determining response times in parallel downloading with capacity constraints on both...

Disponible dans les fichiers attachés à ce document

Timing analysis of real time scheduling policies is concerned with the analysis of response times, because real-time constraints impose that tasks must complete before their deadlines. For the well studied earliest deadline first (EDF) and the fixed priority preemptive (FPP) policy, results are known under various assumptions about tasks. In...

We present the marmoteCore software, an open environment for modeling with Markovchains, developed within the MARMOTE project. 1 This platform aims at providing the generalscientific user with tools for creating Markov models and computing, or simulating, theirbehavior. It provides a software library implementing both basic models and methods...

In this paper, we discuss the problem of estimating the number of "elephants'' in a stream of IP packets. First, the problem is formulated in the context of multisets. Next, we explore some of the theoretical space complexity of this problem, and it is shown that it cannot be solved with less than $\Omega (n)$ units of memory in general, $n$...

We consider a discrete time, infinite horizon dynamic game of groundwater extraction. As usual in this kind of models, the marginal extraction cost depends on the level of the groundwater. The goal of this paper is to point out the importance of the moment where this cost is announced to the players. We consider the case where the cost is...

Prefetching is a basic mechanism in the World Wide Web that speculates on the future behaviour of users to avoid the response delays. The relatively new requirement of the instantaneous response in some interactive services like On-Demand applications fuelled the need for ways to represent and reason about the challenging problem of prefetching...

Prefetching control is a vital operation for the On-demand interactive systems where the instantaneous response is the crucial factor for the system success. The controller in such type of interactive system operates in an uncertain environment and makes sequences of decisions with long and short term stochastic effects. The difficulty, then,...