This paper presents an application of genetic algorithms (GAs) to nonl
inear constrained optimization. GAs are general purpose optimization a
lgorithms which apply the rules of natural genetics to explore a given
search space. When GAs are applied to nonlinear constrained problems,
constraint handling becomes an important issue. The proposed search a
lgorithm is realized by GAs which utilize a penalty function in the ob
jective function to account for violation. This extension is based on
systematic multi-stage assignments of weights in the penalty method as
opposed to single-stage assignments in sequential unconstrained minim
ization. The experimental results are satisfactory and agree well with
those of the gradient type methods.