I'm using global optimization toolbox (both simulated annealing and genetic algorithm) to perform an optimization. But the change happening in the objective function after each iteration is minuscule and the result that I'm getting is unsatisfactory. I must mention that the number of design variables is 66. Can you suggest particular changes that need to be done in the "option" structure of these tools to make them suitable for large number of design variables. Or is there something else that I'm missing out? I feel that the tool is unable to make significant alteration in the design variables in each iteration.