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Outsourcing logistics operation to third-party logistics has attracted more attention in the past several years. However, very few papers analyzed fuel consumption model in the context of outsourcing logistics. This problem involves more complexity than traditional open vehicle routing problem (OVRP), because the calculation of fuel emissions depends on many factors, such as the speed of vehicles, the road angle, the total load, the engine friction, and the engine displacement. Our paper proposed a green open vehicle routing problem (GOVRP) model with fuel consumption constraints for outsourcing logistics operations. Moreover, a hybrid tabu search algorithm was presented to deal with this problem. Experiments were conducted on instances based on realistic road data of Beijing, China, considering that outsourcing logistics plays an increasingly important role in China's freight transportation. Open routes were compared with closed routes through statistical analysis of the cost components. Compared with closed routes, open routes reduce the total cost by 18.5% with the fuel emissions cost down by nearly 29.1% and the diver cost down by 13.8%. The effect of different vehicle types was also studied. Over all the 60-and 120-node instances, the mean total cost by using the light-duty vehicles is the lowest.

Understanding the effects of different sowing patterns and densities on plant growth characters and yield of peanut is essential for the design and adjustment of management practices that allow improvement and stabilization of peanut production. In the present study, Arachis hypogaea L. cv. Luhua 11 was used to determine the effects of planting density on pod development and yield of peanuts under the mode of single seeded precision sowing through field experiments. The results showed that an appropriate precision sowing density of 195,000-225,000 per hectare leads to an optimal pod number to produce pods, with dry matter accumulation resulting in significantly increased pod yield and harvest index(HI). When the same area sowing seed number of 255,000 per hectare, the kernel yield, pod yield, and HI per plant of the single seeded precision sowing method were higher than those of the double seeded precision sowing method.

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