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Scheduling an interval ordered precedence graph with communication delays and a limited number of processors

Alix Munier Kordon, Fadi Kacem, Benoît Dupont de Dinechin, Lucian Finta (2013)

RAIRO - Operations Research - Recherche Opérationnelle

We consider the scheduling of an interval order precedence graph of unit execution time tasks with communication delays, release dates and deadlines. Tasks must be executed by a set of processors partitioned into K classes; each task requires one processor from a fixed class. The aim of this paper is to study the extension of the Leung–Palem–Pnueli (in short LPP) algorithm to this problem. The main result is to prove that the LPP algorithm can be extended to dedicated processors and monotone communication...

Scheduling electric power generators using particle swarm optimization combined with the lagrangian relaxation method

Huseyin Balci, Jorge Valenzuela (2004)

International Journal of Applied Mathematics and Computer Science

This paper describes a procedure that uses particle swarm optimization (PSO) combined with the Lagrangian Relaxation (LR) framework to solve a power-generator scheduling problem known as the unit commitment problem (UCP). The UCP consists of determining the schedule and production amount of generating units within a power system subject to operating constraints. The LR framework is applied to relax coupling constraints of the optimization problem. Thus, the UCP is separated into independent optimization...

Scheduling in the presence of processor networks : complexity and approximation

Vincent Boudet, Johanne Cohen, Rodolphe Giroudeau, Jean-Claude König (2012)

RAIRO - Operations Research

In this paper, we study the problem of makespan minimization for the multiprocessor scheduling problem in the presence of communication delays. The communication delay between two tasks i and j depends on the distance between the two processors on which these two tasks are executed. Lahlou shows that a simple polynomial-time algorithm exists when the length of the schedule is at most two (the problem becomes 𝒩𝒫-complete when the length of the schedule ...

Scheduling in the presence of processor networks : complexity and approximation

Vincent Boudet, Johanne Cohen, Rodolphe Giroudeau, Jean-Claude König (2012)

RAIRO - Operations Research

In this paper, we study the problem of makespan minimization for the multiprocessor scheduling problem in the presence of communication delays. The communication delay between two tasks i and j depends on the distance between the two processors on which these two tasks are executed. Lahlou shows that a simple polynomial-time algorithm exists when the length of the schedule is at most two (the problem becomes 𝒩𝒫-complete when the length of the schedule ...

Scheduling jobs in open shops with limited machine availability

Jacek Błażewicz, Piotr Formanowicz (2002)

RAIRO - Operations Research - Recherche Opérationnelle

In this paper, open shop scheduling problems with limited machine availability are studied. Such a limited availability of machines may appear in many real-life situations, e.g. as preventive maintenance activities. Three types of jobs are distinguished: non-preemptable, resumable and preemptable. An operation of a resumable job if not completed before a non-availability period of a machine may be suspended and continued without additional cost when the machine becomes available. In the paper, results...

Scheduling jobs in open shops with limited machine availability

Jacek Błażewicz, Piotr Formanowicz (2010)

RAIRO - Operations Research

In this paper, open shop scheduling problems with limited machine availability are studied. Such a limited availability of machines may appear in many real-life situations, e.g. as preventive maintenance activities. Three types of jobs are distinguished: non-preemptable, resumable and preemptable. An operation of a resumable job if not completed before a non-availability period of a machine may be suspended and continued without additional cost when the machine becomes available. In the paper,...

Scheduling multiprocessor tasks on two parallel processors

Jacek Błażewicz, Paolo Dell'Olmo, Maciej Drozdowski (2002)

RAIRO - Operations Research - Recherche Opérationnelle

In this work scheduling multiprocessor tasks on two parallel identical processors is considered. Multiprocessor tasks can be executed by more than one processor at the same moment of time. We analyze scheduling unit execution time and preemptable tasks to minimize schedule length and maximum lateness. Cases with ready times, due-dates and precedence constraints are discussed.

Scheduling multiprocessor tasks on two parallel processors

Jacek Błażewicz, Paolo Dell'Olmo, Maciej Drozdowski (2010)

RAIRO - Operations Research

In this work scheduling multiprocessor tasks on two parallel identical processors is considered. Multiprocessor tasks can be executed by more than one processor at the same moment of time. We analyze scheduling unit execution time and preemptable tasks to minimize schedule length and maximum lateness. Cases with ready times, due-dates and precedence constraints are discussed.

Scheduling UET Trees with Communication Delays on two Processors

Frederic Guinand, Denis Trystman (2010)

RAIRO - Operations Research

In this paper, we present a new linear time algorithm for scheduling UECT (Unit Execution and Communication Time) trees on two identical processors. The chosen criterion is the makespan. The used strategy is based on clustering of tasks. We show that this algorithm builds optimal schedules. Some extensions are discussed for non UECT tasks.

Scheduling with periodic availability constraints and irregular cost functions

Francis Sourd (2007)

RAIRO - Operations Research

This paper addresses a one-machine scheduling problem in which the efficiency of the machine is not constant, that is the duration of a task is longer in badly efficient time periods. Each task has an irregular completion cost. Under the assumption that the efficiency constraints are time-periodic, we show that the special case where the sequence is fixed can be solved in polynomial time. The general case is NP-complete so that we propose a two-phase heuristic to find good solutions. Our approach...

Secuenciación dinámica de sistemas de fabricación flexible mediante aprendizaje automático: análisis de los principales sistemas de secuenciación existentes.

Paolo Priore, David de la Fuente, Javier Puente, Alberto Gómez (2001)

Qüestiió

Una forma habitual de secuenciar de modo dinámico los trabajos en los sistemas de fabricación es mediante el empleo de reglas de secuenciación. Sin embargo, el problema que presenta este método es que el comportamiento del sistema de fabricación dependerá de su estado, y no existe una regla que supere a las demás en todos los posibles estados que puede presentar el sistema de fabricación. Por lo tanto, sería interesante usar en cada momento la regla más adecuada. Para lograr este objetivo, se pueden...

Simulated Annealing and Tabu Search for Discrete-Continuous Project Scheduling with Discounted Cash Flows

Grzegorz Waligóra (2014)

RAIRO - Operations Research - Recherche Opérationnelle

Discrete-continuous project scheduling problems with positive discounted cash flows and the maximization of the NPV are considered. We deal with a class of these problems with an arbitrary number of discrete resources and one continuous, renewable resource. Activities are nonpreemptable, and the processing rate of an activity is a continuous, increasing function of the amount of the continuous resource allotted to the activity at a time. Three common payment models – Lump Sum Payment, Payments at...

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