In this paper, the problem of determining the best schedule for a set of projects has been modeled in the form of a generalized tardiness flowshop (GTF) problem. We develop a set of heuristic algorithms for minimizing the total tardiness of jobs in a GTF problem. In the generalized version of tardiness flowshop problems, a job is considered to be a collection of operations and there is a due da...

Producing customized products to respond to changing markets in a short time and at a low cost is one of the goals in agile manufacturing. To achieve this goal customized products can be produced using an assembly-driven product differentiation strategy. The successful implementation of this strategy lies in efficient scheduling of the system. However, little research has been done in addressin...

An implementation of a genetic algorithm for the n/m/P/Cmax sequencing problem is presented, and two performance enhancements hybridisation with a local search algorithm, and a `string fridge` are evaluated. This implementation is then extended to allow the genetic algorithm to optimise the placement of additional processing units to enhance productivity, and to meet order deadlines. Finally, p...

This paper presents an MILP model for the permutation flowshop wherein the setup times are both separable from the job processing times and independent of a job’s position in the processing sequence. Two experiments were conducted to estimate the computer times necessary to solve problems with up to 9 machines and 15 jobs, and to then compare these solution time requirements to those required ...

The proposed hybrid stage shop scheduling (HSSS) model, inspired from a real case in the high-fashion industry, aims to fully exploit the potential of parallel resources, splitting and overlapping concurrent operations among teams of multifunctional machines and operators on the same job. The HSSS formally extends mixed shop scheduling (a combination of flowshop and open shop), which is able to...

We consider the problem of minimizing the makespan in a flowshop involving maximal and minimal time lags, denoted by Fm|θ, θ|Cmax. Time lag constraints generalize the classical precedence constraints between operations: minimal (respectively maximal) time lags indeed specify that the time elapsed between two operations must be lower(respectively upper-) bounded. We assume that such constraints ...

The manufacturing processes of a chip resistor are very similar to a flowshop scheduling problem only with minor details which can be modeled using some extra constraints; while permutation flowshop scheduling problems (PFSPs) have attracted much attention in the research works. Many approaches like genetic algorithms were dedicated to solve PFSPs effectively and efficiently. In this paper, a n...

Flowshop scheduling is an interdisciplinary challenge of addressing major optimality criteria of minimizing makespan and total-flow-time. The enumerations for finding the probabilities for improving the utilization of resources turn this problem towards NP-Hard. Particle Swam Optimization (PSO) has proven its ability to find of near optimal solution when problem size is large. Local search tech...

In this paper, we consider a flowshop scheduling problem with sequence-dependent setup times and a bicriteria objective to minimize the work-in-process inventory for the producer and to maximize the customers’ service level. The use of a bicriteria objective is motivated by the fact that successful companies in today’s environment not only try to minimize their own cost but also try to fulfill ...

This paper deals with the heuristic solution of flexible flowshop scheduling problems with unrelated parallel machines. A setup time is necessary before starting the processing of a job, where the setup time depends on the previous job. No preemption of jobs is allowed. As objective function, this paper considers the minimization of the positively weighted convex sum of makespan and the number ...