Multi-objective optimization for process control of the in-situ bioremediation system

The process control of in-situ bioremediation system is complex and involves multiple objectives. An interactive multi-objective decision-making tool has been developed for process control of the in-situ bioremediation system. The controller consists of three steps. First, the evolutionary multi-objective optimization method is used to identify a set of optimal control strategies and costs corresponding to different efficiency requirements. Secondly, the costs and efficiencies are normalized based on results from a questionnaire that has been developed for acquiring information about the normalization functions. In the third step, the interactive system acquires the user's preferences on tradeoffs of the two objectives of cost and efficiencies. Then the system generates the optimal control strategy using genetic algorithm. The interactive system has been applied to a case study. The results show that the control system can taken into consideration relative importance of each objective and generate a set of optimal strategies based on the particular requirements of the decision maker.