The spatial information of high-resolution remote sensing images is more abundant, and the expression of ground object information in detail is clearer. Vegetation is a component of the environment and the most important component of terrestrial ecosystems. Therefore, vegetation information extraction from remote sensing images is particularly significant. This paper takes Shanghai Pudong New Area as the research area, adopts threshold classification method and membership function classification method to extract vegetation information, and introduces normalized vegetation index as feature to extract vegetation information from WorldView-3 satellite remote sensing image. The results show that the accuracy of vegetation information extraction based on membership function classification method is higher. The classification accuracy of typical vegetation area is higher than 90%, and the Kappa coefficient is higher than 0.86, which can significantly reduce the fragmentation caused by classification. At the same time, high-resolution remote sensing images show great potential for the extraction of vegetation information in urban areas.
The research showed the simulation of position error when assembling a reflective mirror of parabolic trough concentrator. The shape of a reflective mirror is like a parabolic cylinder model, relying on the back of the four-point mounted on a special setup, making it unable to move. Therefore, it is of great importance of the machining precision of special bracket. We need to analyze the influence of reflective mirror‘s intercept factor in order to guide the processing precision. It is assumed that each reflective mirror is rigid, we have calculated the intercept factor of reflector with mounting points’ random error of different standard deviation, comparing the simulating results with TRACEPRO. As a sequence, we can approve the feasibility of the algorithm, and give the effect of different random errors on the light-gathering efficiency. On the basis, we provide the machining accuracy of bracket. The simulation results show that when the mounting points’ standard deviation of position error is less than 0.5 mm, the intercept factor of receiver has reached upwards of 92% with 60 mm diameter for receiver, which can satisfy the design requirements.