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Manufacturers are increasingly selling extended warranties to achieve high profitability. An important question is to sell the traditional or flexible extended warranty (TEW vs. FEW). TEW is sold at the time of product sales with a uniform price, while FEW can be sold at the time of product sales (the first point) or at the end of base warranty (the second point) with nonuniform prices. When selling FEW, manufacturers need to decide whether to preannounce the difference between the first-point and second-point warranty prices. To address such challenging issues, we develop theoretical models regarding selling TEW or FEW and find that neither of the two warranty services is always superior to the other. Particularly, FEW outperforms TEW when the manufacturer's cost efficiency of warranty is relatively high and/or the total warranty duration is relatively short. Interestingly, when selling FEW, it is not always better off concealing the price difference information, which is counterintuitive.

The initial period after the earthquake is the prime time for disaster relief. During this period, it is of great value to rationally locate the transfer facilities of relief materials and effectively arrange the transportation of relief materials. Considering the characteristics of the two-level emergency logistics system including uncertain demand, uncertain transportation time, multiple varieties of relief materials, shortage of supply, multi-transportation modes and different urgencies of relief material demand, the integrated issue with the concern of transfer facility location and relief material transportation is studied. Then, this problem is formulated as a grey mixed integer bi-level nonlinear programming in which the upper-level aims at the shortest relief material transportation time and the lower-level aims at the maximum fairness of relief material distribution. According to the characteristics of the model, a hybrid genetic algorithm is designed to solve the proposed model. Finally, a numerical simulation is carried out on the background of 5.12 Wenchuan Earthquake. In addition, the validation of the proposed model and algorithm is verified.

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In delivering perishable goods, certain unexpected disruptive events may cause the initial routing scheme to be infeasible. A new routing scheme must be generated quickly to alleviate delivery disturbances. According to the idea of disruption management, a disruption recovery model with a distinctive type of split delivery is developed for inter-route recourse based on an initial time-dependent vehicle routing model with time windows, which synthesizes the perishable nature of delivered goods and dynamic travel route choice in urban road networks. Then, a tabu search algorithm is proposed to solve the initial routing problem and further extended to generate the disruption recovery plan. Three computational experiments on the instances adapted from Solomon's and Gehring and Homberger's benchmark problems are conducted to illustrate the effectiveness of the proposed model and algorithm. INDEX TERMS Vehicle routing, disruption management, time-dependent, time windows, split delivery.