Algorithm for increase the transportation network capacity with minimum cost

This paper presents the problem of increasing the capacity of a transportation network with minimal costs. Supposing we have a transportation network that simulates a real situation and we need to increase the capacity of network with a specified quantity from the substance transported. The most algorithms that solve transportation network consider the arcs transportation capacity for determining the maximum of the capacity of the network. But real network are formed by real elements (roads, pipes etc.). If we need to increase the capacity of the network we have two solutions: increase the capacity of one or many existing arcs or installing a new arc between two nodes. This problem involves a total cost of the operations that depend on the selected solution. The scope of this work is to determine the minimum cost for increasing the capacity of a transportation network with a determined value.