Research On Hub Network Design With Single Assignment And Multiple Assignements

We extract a network structure from an automobile spare parts logistics company's realistic problem, which is different from the network in previous logistics network literature. After exploring the unique nature of this network, we compare it with hub-spoke network and hierarchy network which are studied widely in the literature. Then we formulate the mathematical model of this type of network when the number of regional distribution centers is fixed and the fixed cost of a regional distribution center is 0. After that we propose a heuristics algorithm based on shortest path and simulated annealing. We show the efficiency of our algorithm by comparing our algorithm with Cplex via small instances and comparing our algorithm with another heuristics algorithm with large instances. Besides heuristics algorithm, we propose an exact algorithm based on Benders decomposition. By employing the special property of our model, the model can be solved relatively easy when the regional distribution center is fixed. Through various numeric instances, we prove that our algorithm can get the result faster than Cplex.Finally we extend our model to the circumstance that regional distribution centers'fixed cost is considered and the number of regional distribution center is a variable. We still apply simulated algorithm and Benders decomposition to this model. The comparison of large set of instances between these two algorithms and Cplex also demonstrates that our algorithms are efficient. We use a case, which is partially based on a company's data, to test our model and the algorithm which shows that our model and algorithm are very consistent with the realistic circumstance.