389
which is a typical system used in the hospitals of
Thailand and belongs to the class of individual
block/fixed interval. The adaptive-penalty GA has
been applied in determining the optimal number of
doctors and appointment interval. Using the adap-
tive penalty scheme, optimization constraints could
be automatically and numerically handled. Since
GA operates in a numerical manner, the algorithm
is applicable to practical problems where explicit
expressions of objective functions and constraints
are not possible to derive. The application of the
proposed methodology has been shown through a
numerical example in which the uncertainty of sys-
tem and input is incorporated. The numerical result
has shown that the proposed methodology could