Abstract We present in this paper a generalization of the one-commodity pickup and delivery traveling salesman problem where each customer supplies or demands a given amount of a certain product. The objective is to design a minimum cost two-echelon transportation network. The first echelon is the route of a capacitated vehicle that visits some customers, and the second echelon consists in the allocation of the non-visited customers to visited ones. The customers that must be visited by the vehicle and the ones that must be allocated to others are not predefined. We presentthree mathematical models for the problem, design an exact branch-and-cut algorithm to solve it, and show extensive computational results on benchmark instances.

中文翻译：

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单车两梯队一品提货问题

摘要 我们在本文中提出了单一商品提货和送货旅行商问题的概括，其中每个客户供应或要求给定数量的某种产品。目标是设计一个成本最低的两梯队交通网络。第一梯队是有能力的车辆访问一些客户的路线，第二梯队包括将未访问的客户分配给访问的客户。车辆必须访问的客户和必须分配给其他人的客户不是预先定义的。我们提出了该问题的三个数学模型，设计了一个精确的分支和切割算法来解决它，并在基准实例上展示了广泛的计算结果。