Abstract
This paper deals with an optimaization problem of assembled parts for product variety which was introduced by Futagami et al. [6]. The problem was formulated as is an integer programming problem whose criterion function has non-linear term. First we note that this problem may be formulated as a facility location problem which is introduced as a relaxation problem. It is also shown that the problem may be formulated to a linear programming with 0-1 variables. Related to a key to solution for the optimization problem, we introduce a continuous relaxation problem which is a linear programmings problem. This relaxation problem can be used as a lower bound for the original problem. Further, it is shown that under some condition an optimum solution of the relaxation problem becomes to the solution of the original problem.
