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To solve a series of problems (including high cost and delivery delay) during takeaway delivery, a model for the vehicle routing problem (VRP) during goods pickup and delivery is developed by considering constraints such as the capacity of delivery vehicles, delivery mileage and time window. The model is constructed by transforming the satisfactions of merchants and customers into a penalty function and aiming to minimise the total delivery cost. As for the drawbacks in a conventional genetic algorithm (CGA), such as a low convergence rate and locally optimum solutions, an improved GA (IGA) is designed by separately using the insertion heuristic algorithm to construct initial solutions and introducing the forward continuous crossover and differential mutation strategies. On the one hand, the numerical analysis and test of weights indicate that the model can reduce the delivery cost of enterprises offering takeaway service and improve satisfactions of merchants and customers. It verifies that reasonably considering satisfactions of merchants and customers during vehicle routing is conducive to cost-reduction and increased efficiency of enterprises. On the other hand, a simulation is conducted to compare and analyse various algorithms based on two different scales of test examples, which validates the proposed algorithm as effective. The study provides a theoretical basis and decision reference for enterprises offering takeaway service to improve delivery efficiency and competitiveness.

To evaluate the cost-benefit of comprehensive parasitic disease control project in Rongxian County of Guangxi, so as to provide the evidence for formulating the control strategy of soil-transmitted nematode.The data of the overall input and output for soil-transmitted nematode control were collected from 2007 to 2009, and the cost-benefit was analyzed.The infection rates of soil-transmitted nematode dropped from 30.10% in 2007 to 12.30% in 2009. The overall cost of soil -transmitted nematode control was 969 185.6 Yuan from 2007 to 2009. The direct benefits arising from avoiding the incidence of the disease for populations reached 88.415 million Yuan in three years. The ratio of benefit-cost was 91:1.The soil -transmitted nematode infection brings a heavy financial burden on both the patients and society. The implementation of comprehensive control measures can effectively control the prevalence of the diseases and produce good social and economic benefits.

The input document images with skew can be a serious problem in the optical character recognition system. A method is proposed for skew detection in binary document images using mathematic morphology. The basic process of our approach consists of three steps: Firstly, a dilation operation is applied to the binary image; Secondly, the dilated image is thinned; Finally, the skew angle is detected using the Hough transform. The proposed approach with high precision can detect skew with large angle (−90δ-90Δ). The experimental result shows this method is applicable and efficient.