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The transportation of hazardous materials may result in significant social risks. The route planning is one of the most effective measures to reduce the risk and the cost. A new probability model based on time dependent of links is developed. The routing algorithm based on the model is also put forward to find the optimal route whose sum of weighted risk-cost is the least. An example is introduced to verify its usability. The model is convenient for carrier to select the optimal route by adjusting the probability distribution in different time slots of links according to the real situation.

The transportation of containers is an important part of the modern logistics industry. As a result of unbalance freight volume between different regions, the empty container allocation has already become a very important and valuable research project. Taking into account the limitations of capacity in railway lines and multiple types of containers, this paper treats the railway empty container allocation as a multi-origin, multi-destination, and multi-commodity problem. An optimal model of this problem is formulated. In view of the interact ability in solving the model, a heuristic method is developed. A numeric example indicates that the model is correct and the method is effective.

In railway passenger transportation systems, it is a practical significance to find riding route. It is very difficult for passengers to choose the best transfer routes when a transportation network is complex. Considering the traits of railway transportation networks, we formulate a 0-1 programming model and a hypergraph model to the optimal path problem with transfer times limited. An improved priority-based encoding genetic algorithm is presented to solve the models. By using the method proposed in the paper, the transfer paths in the railway transportation network are analyzed and calculated. Finally, we give a numerical example. The computer simulations show the effectiveness of the proposed methods.