Cell formation problem with alternative process plans and alternative routes considering defect rate

This paper presents cell formation (CF) problem in dynamic condition with multiple alternative process plans and a set of alternative routes for each of process plans. Previous models paid attention to just one of the terms of process plans and routes and also they have not reflected the notion of defect rate after operations. Therefore, this paper also addresses defect rate. The proposed model seeks to minimize cell formation costs as well as the costs associated with production, while dynamic conditions, alternative routing, machine capacity limitation, cell size constraints, and outsourcing are also taken into account. The proposed model is solved in small, medium and large sizes to which a hybrid meta-heuristic approach is developed to cope. The developed algorithm consists of Simulated Annealing (SA) and Particle Swarm Optimization (PSO) to solve the problem in large scale due to high level of computational complexity. In the developed algorithm, the SA algorithm is applied to generate initial solution for the PSO. The comparison between results of exact and meta-heuristic methods for both small and medium scale problems confirms efficiency of the developed hybrid meta-heuristic approach.