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The motion commands to feed drives constitute a major source for excitation of the vibrations. In this paper the vibration of feed drive caused by the motion commands is simulated by using a mathematic method. The mechanical transmission system is modeled as a dual inertia system. Three typical trajectories are used to analyze the effect of motion profiles on feed drive vibration by using a simulation model of feed drive controller.

The development of shale gas can influence the land use and exacerbate the problem of land use. The drilling and fracturing of a well need a large well site. Taking all the coverage of road building, platforms and pipelines into account, the average coverage of every well is near 16.2 hectares. More than 80 shale gas wells have been drilled and covered 1296 hectares. According to the development plan of shale gas of China, more than 300 shale gas wells will be drilled and will occupy 6156 hectares land to 2015. To the end of 2020, about 1.6~1.7×104 shale gas wells will have been drilled and 27.54×104 hectares land will be occupied. The quality of land is damaged during the process of shale gas development, lowering the soil fertility and making the land reclamation more difficult. During the process of shale gas development, the assessment and supervision and management system of land use should be reinforced and land use and reclamation should be reasonably planned. The efficiency and sustainability of land use can be improved by technology innovation of well drilling.

The impact of green purchasing on the enterprise performance was analyzed in this paper. An empirical study in the China textile and garment industry was carried out, and research results show that the five dimensions of green purchasing (Supply chain management, Ecological design, Operation management, External environment management and Environmental authentication) have significant impact on enterprise performance.