  This paper mainly investigates the circular open dimension problem (CODP),
which consists of packing a set of circles of known radii into a strip of fixed
width and unlimited length without overlapping. The objective is to minimize
the length of the strip. An iterated tabu search approach, named ITS, is
proposed. ITS starts from a randomly generated solution and attempts to gain
improvements by a tabu search procedure. After that, if the obtained solution
is not feasible, a perturbation operator is subsequently employed to
reconstruct the incumbent solution and an acceptance criterion is implemented
to determine whether or not accept the perturbed solution. This process is
repeated until a feasible solution has been found or the allowed computation
time has been elapsed. Computational experiments based on well-known benchmark
instances show that ITS produces quite competitive results with respect to the
best known results. For 18 representative CODP instances taken from the
literature, ITS succeeds in improving 13 best known results within reasonable
time. In addition, for another challenging related variant: the problem of
packing arbitrary sized circles into a circular container, ITS also succeeds in
improving many best known results. Supplementary experiments are also provided
to analyze the influence of the perturbation operator, as well as the
acceptance criterion.
