Optimal design of buffer material in the geological disposal of radioactive wastes using the satisficing trade-off method and a self-organizing map

In this paper, we consider the use of a multi-objective optimization method in order to obtain a preferred solution for the buffer material optimal design problem in the high-level geological disposal of radioactive waste. The buffer material optimal design problem is formulated as a constrained multi-objective optimization problem. Its Pareto optimal solutions are distributed evenly over the entire feasible region. Hence, we develop a search method to find a preferred solution easily for a decision maker from the Pareto optimal solutions, which are distributed evenly and broadly. In the preferred solution search method, a technique for visualization of a Pareto optimal solution set using a self-organizing map is introduced into the satisficing trade-off method, which is an interactive method for obtaining a Pareto optimal solution that satisfies a decision maker. We confirm the effectiveness of the preferred solution search method in the buffer material optimal design problem.