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Collaborative multicenter pickup and delivery problems with time window assignment (CMPDPTWA) are introduced in this paper and formulated and solved as a two-stage optimization problem. First, the collaborative mechanism achieves optimal transportation resource configuration in a multicenter logistics network. Second, open-closed mixed pickup and delivery routes satisfying the demands and time windows of customers are proposed to enhance transportation efficiency and reduce the total logistics operating cost. A set of candidate-time windows is assigned to the corresponding customers through time window assignment (TWA) strategy to increase the operational efficiency of logistics network. A bi-objective programming model for CMPDPTWA is formulated to minimize the number of vehicles and total operating cost. An improved k -means clustering algorithm is used to cluster customers according to their proximities to pickup and delivery centers for reducing the computational complexity to solve the abovementioned problem. A self-learning non-dominated sorting genetic algorithm-II (SNSGA-II) is proposed to optimize the open-closed mixed pickup and delivery routes in CMPDPTWA. An update mechanism for the probabilities of crossover and mutation is devised to improve the efficiency of searching the solution space, and thus to accelerate the convergence of SNSGA-II. The performance of the proposed algorithm is compared with that of other algorithms, and the results indicate that it can generate near-optimal solutions for CMPDPTWA. A game theoretical method involving a cost gap allocation model and the strictly monotonic path strategy is proposed to find the best profit allocation scheme and the optimal coalition sequence for stabilizing the collaborative coalition. Finally, the proposed method is applied to a case study using the real-world logistics network in Chongqing City, China. Six scenarios with and without the collaborative mechanism and TWA strategy are simulated and compared with one another to verify the efficacy of the proposed method. The results show that the collaborative mechanism and TWA strategy can improve the utilization of transportation resources and operational efficiency. Thus, they can facilitate an efficient and sustainable urban logistics network. • Collaborative multicenter pickup and delivery problems with TWA is studied. • A bi-objective optimization model is developed based on collaborative networks. • A hybrid method with k -means clustering and SNSGA-II is devised to solve the model. • Profit allocation and coalition stability are tested under different game methods. • A case study is conducted to show the applicability of proposed approach. [ABSTRACT FROM AUTHOR]

Abstract: It is difficult to evaluate the performance of the different companies feasibly and fairly only depending on experts. An evaluation model based on TOPSIS (Technique for Order Preference by Similarity to Ideal Solution) is built to solve this problem. In this model, the method of data processing and the evaluation algorithms are analyzed detailed. By means of the evaluation model, eight electric power supply bureau of Chongqing are evaluated in this paper, and the results show feasibly and reasonably. [Copyright &y& Elsevier]