摘要 |
PROBLEM TO BE SOLVED: To create a raw material purchase and use plan in a short time by turning constraint equations and objective functions given in nonlinear expressions into a mathematical programming problem in linear expressions.SOLUTION: The present invention relates to creating a raw material purchase and use plan for minimizing costs needed for the purchase and manufacture of raw materials (iron ore, coke, coal, and auxiliary material) while observing constraints pertaining to the properties of products (pig iron, sintered ore, and slag) and the capacities of manufacturing facilities. In this case, prescribed variables included in constraint equations and objective functions are fixed, and nonlinear terms remaining as nonlinear expressions even after the fixation of the prescribed variables are removed, and thereby the constraint equations and objective functions are turned into linear expressions. Then, a mathematical programming problem expressed by the constraint equations and the objective functions turned into the linear expressions is solved, and the amounts of the raw materials purchased and used that minimize the objective functions, and the properties and amounts of the products are calculated.SELECTED DRAWING: Figure 2 |