Abstract
A transport system in Japan has faced many new challenges since the first oil crisis took place in 1973. Besides the limited oil supply, there is also other requirement such as making up an optimum system. But the method of evaluation of transport system does not attain the perfection yet, and an evaluation of energy system is pointed out to be confused. It is extremely important to understand that transmission is widely different from consumption in evaluation of energy system, and also important to develop a mathematical model that evaluates a transport system. Realizing this point early, a study of this subject has been commenced and recently theoretical results have been obtained. In this paper, considering a simple model of energy flow, a mechanism of hierarchical structure of transport systems has been analyzed.
