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Different from the conventional logistics service network design problem, we design a fast logistics service network based on high-speed railway. An integrative optimization model which is applicable for solving practical problems is established. This paper simultaneously considers three subproblems: Train timetabling, freight flow assignment and electrical multiple units (EMU) routing plan, in which the objectives are simultaneous to minimize the total train travel time, the operation cost and transportation cost of freight transport, the number of freight EMU and the number of maintenance tasks. The constraints imposed in the model include space-time path resource assignment restriction, node operation capability, train safety interval time, train connection time restriction, freight service time window, train loading capacity restriction and EMU routing restriction. Based on the thoughts of divide and conquer, the original problem is decomposed by using the decomposition mechanism of the Lagrange relaxation algorithm to solve the integrated optimization model. To verify the feasibility and effectiveness of the model and algorithm proposed in this paper, a case study is conducted based on Harbin Dalian high-speed railway.

Global routing is an essential phase during the process of physical design of integrated circuits. Combinatorially, this problem amounts to a set of interdependent Steiner tree problems. Several versions of the problem are of importance in practical applications. All of them can be formulated as integer programs. Several such formulations have been investigated in the past, and different solution methods have been developed for different formulations.

In this paper we give an overview of integer program formulations of the global routing problem and their solution methods, and we introduce new concepts for solving this important combinatorial problem. Finally, we present integer program formulations that integrate placement with global routing.