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In this paper, the sand break into highway problem in desert, which is caused by the sand flow blown by wind, is studied. The mathematical models are introduced by considering the fixed, semi-fixed and free sand desert fields based on the fluid dynamics and the sand particle dynamics. Different kinds of numerical models are made by changing the desert highway height, wind flow direction and its uniformity. The weak coupling method is used due to spatial relationships between air flow field and the sand flow field. Finally, by coupling the airflow field and sand flow field with desert highway, the numerical simulations of sand forming process on desert highway are conducted. The numerical results shown, that the wind blown sand breaks into highway easier when wind direction perpendicular highway and if the highway height higher than the range size of the sand surface the wind blown sand break into highway is more difficult.

The numerical controlled plastic film cutting machine in our design is used for flower bags making. It is composed of four parts; cutting mechanism, delivering mechanism, tool rest and machine bed. The tool rest is a critical structure to cutting and adhering operations. The tool rest is a long -thin rod with big span, usually it’s failure is because of bending deformation caused by less stiffness. In this study, we finished FEM 3D modeling of tool rest structure to increase its structure stiffness. We analyzed bending deformation characteristics of the tool rest, performed 3D FEM analysis and choose a relatively reliable structure after comparing maximum deformation in three different candidate structures. As a result, support structure of the tools rest was optimized, providing us a numerical data for structure reformation.

In this paper, based on survey data of delays on intersections in urban highways and in accordance with theoretical capacity of each traffic lane, various reasons of delay in intersections are analyzed numerically. A discrete traffic model to simulate traffic in intersections using Gaussian mesh method is built. After modifying intersection properties, weight of each factor in terms of their effect to capacity is acquired. An optimized way to solve traffic delay is hereby recommended.

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