In this paper we have formulated two new production-transportation models: the model of discrete production-transportation problem and the model of bilevel discrete transportation problem. We have solved the models on two sets of available real-life data from a petroleum industry and we have compared the results.
In our future work we plan to consider some further extensions of the models proposed such as discrete production-transportation problem with several modes of transportation, discrete production-transshipment transportation problem with the warehouses between the producers and the customers, and multimodal discrete production-transportation problem with capacity constraints. Furthermore, it would be interesting to formulate the D-PTP and BD-PTP as network problem due to the existence of many efficient network algorithms.