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An improved ant algorithm for Multi-mode Resource Constrained Project Scheduling Problem

Peng Wuliang, Huang Min, Hao Yongping (2014)

RAIRO - Operations Research - Recherche Opérationnelle

Many real-world scheduling problems can be modeled as Multi-mode Resource Constrained Project Scheduling Problems (MRCPSP). However, the MRCPSP is a strong NP-hard problem and very difficult to be solved. The purpose of this research is to investigate a more efficient alternative based on ant algorithm to solve MRCPSP. To enhance the generality along with efficiency of the algorithm, the rule pool is designed to manage numerous priority rules for MRCPSP. Each ant is provided with an independent...

An introduction to multiprocessor scheduling.

J.K. Lenstra, A.H.G. Rinnooy (1981)

Qüestiió

This is a tutorial survey of recent results in the area of multiprocessor scheduling. Computational complexity theory provides the framework in which these results are presented. They involve on one hand the development of new polynomial optimization algorithms, and on the other hand the application of the concept of NP-hardness as well as the analysis of approximation algorithms.

Batch scheduling problem with due-date and fuzzy precedence relation

Xuesong Li, Hiroaki Ishii, Minghao Chen (2012)

Kybernetika

A single-machine batch scheduling problem is investigated. Each job has a positive processing time and due-date. Setup times are assumed to be identical for all batches. All batch sizes cannot exceed a common upper bound. As in many practical situations, jobs have to be subject to flexible precedence constraints. The aim of this paper is to find an optimal batch sequence. The sequence is to minimize the maximal completion time and maximize the minimum value of desirability of the fuzzy precedence....

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...

Coloration de graphes : fondements et applications

Dominique de Werra, Daniel Kobler (2003)

RAIRO - Operations Research - Recherche Opérationnelle

Les modèles classiques de coloration doivent leur notoriété en grande partie à leurs applications à des problèmes de type emploi du temps ; nous présentons les concepts de base des colorations ainsi qu’une série de variations et de généralisations motivées par divers problèmes d’ordonnancement dont les élaborations d’horaires scolaires. Quelques algorithmes exacts et heuristiques seront présentés et nous esquisserons des méthodes basées sur la recherche Tabou pour trouver des solutions approchées...

Coloration de graphes : fondements et applications

Dominique de Werra, Daniel Kobler (2010)

RAIRO - Operations Research

The classical colouring models are well known thanks in large part to their applications to scheduling type problems; we describe the basic concepts of colourings together with a number of variations and generalisations arising from scheduling problems such as the creation of school schedules. Some exact and heuristic algorithms will be presented, and we will sketch solution methods based on tabu search to find approximate solutions to large problems. Finally we will also mention the use...

Computing the greatest 𝐗 -eigenvector of a matrix in max-min algebra

Ján Plavka (2016)

Kybernetika

A vector x is said to be an eigenvector of a square max-min matrix A if A ⊗ x = x . An eigenvector x of A is called the greatest 𝐗 -eigenvector of A if x ∈ 𝐗 = { x ; x ̲ ≤ x ≤ x ¯ } and y ≤ x for each eigenvector y ∈ 𝐗 . A max-min matrix A is called strongly 𝐗 -robust if the orbit x , A ⊗ x , A 2 ⊗ x , ⋯ reaches the greatest 𝐗 -eigenvector with any starting vector of 𝐗 . We suggest an O ( n 3 ) algorithm for computing the greatest 𝐗 -eigenvector of A and study the strong 𝐗 -robustness. The necessary and sufficient conditions for strong 𝐗 -robustness are introduced and an efficient...

Décomposition temporelle et caractérisation de solutions admissibles pour le problème d'ordonnancement à une machine

M.-L. Levy, P. Lopez, B. Pradin (2010)

RAIRO - Operations Research

We propose a temporal decomposition approach for the one-machine scheduling problem with ready times and due dates. A set of feasible schedules is characterized by means of constraint-based analysis rules. They permit the determination of the feasible locations of each task in a sequence, represented by rank intervals. A decomposition procedure based on comparisons of rank intervals is developed in order to group tasks to be sequenced in the neighbourhood of each other in a feasible solution. Computational...

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