Decision making is an important aspect managerial activit[Ik the importance and difficulty of performing the task of decision making, opportunities presented by computer technology to decision support for makers have generated a great deal of interest 12) During the 1970s and 1980s, the concept of deci- sion support systems(DSS) grew and evolved into full field of research, development, and practice. They need operation research(OR) methods to analyze and describe the specific problems better(3) The model compo- nent of DSS includes many kinds of OR methods and DSS deeply relies on the model component to seek the optimum solution with some constraints such as linear programming problems and network programming problems[4]. It is the branch of science dealing with techniques for optimizing the performance of systems