The effects of various rolling reductions (64.7%, 72.1%, 81.4% and 88.2%) on the microstructures and mechanical behaviors of Sc-containing Al-3.2Cu-1.5Li-based alloys were experimentally investigated through XRD, SEM (equipped with EBSD), TEM and the tensile test. The results showed that the grains of hot-rolled and T6-treated alloys are mainly dominated by substructure features, and the addition of the trace Sc element can obviously impede the static and dynamic recrystallization due to the formation of fine and stable nano-Al3(Sc, Zr) particles. Additionally, the combined effects of fine grains, dispersion, substructure and precipitation strengthening make the alloys with a rolling reduction of 81.4% possess higher tensile properties. With an increase in the rolling reduction, the tensile strength of the alloys increases first and then decreases, while the elongation gradually increases and then reaches a plateau, which was ascribed to the variation in the grain size and substructure features.

There are many kinds of skills for the workers in the project group, but the present scheduling methods do not consider that the workers have different proficiency in different skills. In this paper, a scheduling model of human resources project is established, which takes the worker’s skill proficiency into account and the project duration and labor cost are considered as the optimization objectives. The improved non-dominated sorting genetic algorithm (NSGAII) is used to solve the model. The simulation results show that the model can significantly improve the scheduling efficiency of the project team, and managers can make scheduling decisions according to preference in a series of solutions.

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