The purpose of this paper is three-fold. Firstly, the exact models from queueing theory for non-stationary conditions which the CTT models should approximate are established and applied so far that they produce concrete results. To the author's knowledge this is done here for the first time. Secondly, the accuracies of the non-stationary models for mean queue lengths and mean waiting times derived from the CTT are investigated. Thirdly, the non-stationary exact models from queueing theory also allow to consider more characteristics than just the mean queue length or the mean waiting time where the CTT models are confined to. Furthermore it is shown in the paper that a well-known approximation formula for mean waiting times which is due to Akcelik and Troutbeck (1991) can also be derived by a slight modification of the CTT. The Akcelik-Troutbeck formula is also included in the comparisons with the exact results, and the agreement is seen to be almost as good as for the Kimber-Ho11is fonnu1as, in general. (Author/publisher) For the covering entry of this conference, please see ITRD abstract No. E208120.
Samenvatting