Sightseeing route planning problem by electric vehicle on the Time-Expanded Network

This paper proposes a sightseeing route planning problem by electric vehicle with time-dependency of traveling times between any two sightseeing sites. In order to represent the time-dependency, Time-Expanded Network (TEN), which contains a copy to the set of nodes in the underlying static network for each discrete time step, is introduced. In addition, it is hard for the tourist to set satisfaction values at sightseeing sites numerically, but it is not difficult to classify sightseeing sites into several groups. Therefore, the objective function of our proposed model is set to maximize the total visiting sightseeing sites in each group. The problem is a multiobjective programming problem, and hence, a principle of compromise is introduced to solve our proposed problem in network optimization. Furthermore, the main constrained network optimization problem is equivalently transformed into a recursive equation, and an exact and greedy algorithm is developed.