The article deals with the gravitation problem, which is widely used for solving different practical problems. First of all it is used to forecast the future traffic of a territory (Origin/destination problem). It is also used in the economy for forecasting the Leontief Input/Output table. It will be shown if the I-divergence is used for the sample O/D matrix and the future traffic matrix the cost function is exponential and the element of the forecasted matrix are determined in the well known RAS form. For the proof the geometric programming and its dual and the week and strong duality theorem are applied. © 2011 IEEE.

The Road Management Systems (and the Pavement Management System-PMS) usually do not take into consideration the changes of future traffic. The maintenance and rehabilitation actions and the development of the road network structure as well as the changing traffic structure modify the amount of the traffic on the road sections. The deterioration process depends on mostly the volume of the traffic. That is why it is important to take into consideration the change of the traffic volume during the planning time horizon. In this paper some techniques are shown which are capable of handling this problem: in the multiperiod, long time model at each planning period the traffic volume change is take into consideration; in the ranking models the problem can also be handled and solved; in the case of the one-period Markov stable model to finding the solution is straightforward. In the multiperiod model a stepwise optimization procedure is used instead of the original algorithm. The objective function is also modified, so that the sum of the differences of the actual solution and the Markov stable model solution is minimized. The result of this algorithm provides a better quality of the road network. The amount of traffic on the sectors depends on the development of the road network also. © 2008 IEEE.