The target function f(x) is the des

The target function f(x) is the desired target form represented by the design variable, so the target function is the function of the design variable, is a scalar. In engineering sense, the target function is the performance standard of the system, for example, the lightest weight, minimum cost, most reasonable form of a structure, the shortest production time and minimum energy consumption of a product, the best formula of an experiment, etc., the process of establishing the target function is the process of finding the relationship between the design variable and the target, the relationship between the target function and the design variable can be represented by curve, surface or supersurface.