Research On Optimization Of Container Multimodal Transportation Under Uncertain Environment

Multimodal transport of the container is the advanced stage of the logistics and transportation, and is regarded as an important symbol of the modernization process of freight transport in various countries. At present, the global intermodal center has transferred to China, the development of multimodal transport in China is just at the right time and gaining momentum. Since the state issued the "long term planning for the development of logistics industry", various places have attached great importance to the development of multimodal transport, accelerated the construction of the logistics channel, and the improvement of the comprehensive transportation system has become primary task of multimodal transport development in China. Chinese development of multimodal transport will accelerate the prosperity of the surrounding market, promote international trade activities and help the country’s "One Belt and One Road" strategy.Considering the circumstance, The paper briefly introduced theoretical knowledge of multimodal transport of the container, applied the multimodal transport to realistic cargo transportation, and gave a comprehensive analysis of uncertain factors in the transport process, then according to the constraints of transport activity and the objective function to construct the multimodal transport optimization model under uncertain environment, and designed a heuristic algorithm based on branch and bound method, Finally, proved the feasibility of the model and algorithm with examples.The main research contents of this paper are as follows:1. According to the actual situation, considering that the multimodal transport costs will be influenced by market factors, the paper regards the transportation costs as interval numbers, and builds an uncertain objective function with transport cost minimization. The transport costs including the transportation costs incurred in transit and conversion costs in transfer station, they are both interval numbers. While taking into account that the transport time will also be influenced by transit vehicles, transit station equipment and human factors, the paper also views the transportation time as interval numbers, and establishes an uncertain model which regarded the transport time and capacity constraints as constraint conditions, The transport time includes transportation time incurred in transit and transit time in the transfer station, They are also the interval numbers, Then through the interval ranking method and the expected value method, the uncertain optimization model will be transferred and can be used to solve the deterministic optimization model. Finally, the heuristic algorithm is used to solve the model.2. In real life, the uncertainty of the multimodal transport may also be the other two kinds of circumstances-fuzzy number and random number. So this paper built another model, in which the transportation cost is regarded as fuzzy number, and the uncertain objective function is established with the minimum transportation cost. And taking into account that the transit time of the goods in most cases has certain randomness, The paper regards the transit time as a random number, and establishes an uncertain optimization model which views the time limit as the constraints. Then, by means of the expectation value method and chance constrained method, the uncertain model is transformed into the specific model. Finally, the corresponding results are obtained by the heuristic algorithm.