This paper proposes two relax and fix heuristics for the simultaneous lot sizing and sequencing problem in permutation flow shops involving sequence-dependent setups and capacity constraints. To evaluate the effectiveness of mentioned heuristics, two lower bounds are developed and compared against the optimal solution. The results of heuristics are compared with the selected lower bound .

This paper provides a test method to make a fair comparison between different heuristics in structure optimization. When statistical methods are applied to the structural optimization (namely heuristics or meta-heuristics with several tunable parameters and starting seeds), the "one problem - one result" is extremely far from the fair comparison. From statistical point of view, the minimal requ...

in recent years stock exchange has become one of the most attractive and growing businesses in respect of investment and profitability. but applying a scientific approach in this field is really troublesome because of variety and complexity of decision making factors in the field. this paper tries to deliver a new solution for portfolio selection based on multi criteria decision making literatu...