In single machine scheduling problems with availability constraints, machines are not available for one or more periods of time. In this paper, we consider a single machine scheduling problem with flexible and periodic availability constraints. In this problem, the maximum continuous working time for each machine increases in a stepwise manner with two different values allowed. Also, the durati...

We present several heuristic algorithms based on tabu search for solving the multi-stage sequence-dependent group scheduling (SDGS) problem by considering minimization of makespan as the criterion. As the problem is recognized to be strongly NP-hard, several meta (tabu) search-based solution algorithms are developed to efficiently solve industry-size problem instances. Also, two different initi...

this article addresses a multi-stage flowshop scheduling problem with equal number of unrelated parallel machines. the objective is to minimize the makespan for a given set of jobs in the system. this problem class is np-hard in the strong sense, so a hybrid heuristic method for sequencing and then allocating operations of jobs to machines is developed. a number of test problems are randomly ge...

In this paper we deal with the two-stage hybrid flow shop with dedicated machines. The objective is to minimize the makespan. We first provide some basic properties, a set of lower bounds and two polynomial cases. We then propose a new heuristic based on the established properties. The heuristic tries to sequence jobs in such a way that the obtained makespan corresponds to the lower bound. In t...

The single-stage scheduling problem to minimize the makespan of identical jobs on uniform parallel machines is known to be solvable in polynomial-time. We extend this work to consider multi-stage systems with flowshop configuration. We show that the 2-stage problem may also be solved in polynomial-time and for the number of stages greater than two, the problem is shown to be NP-hard. We present...

This paper is focusing on an important transportation application encountered in supply chains, namely the capacitated two-stage fixed-charge transportation problem. For solving this complex optimization problem we described a novel hybrid heuristic approach obtained by combining a genetic algorithm based on a hash table coding of the individuals with a powerful local search procedure. The prop...

C often face nonstationary demand due to product life cycles and seasonality, and nonstationary demand complicates supply chain managers’ inventory decisions. This paper proposes a simple heuristic for determining stocking levels in a serial inventory system. Unlike the exact optimization algorithm, the heuristic generates a near-optimal solution by solving a series of independent single-stage ...