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This paper proposed a novel urban building extraction method to address the problems with shadow and spectral confusion using LiDAR data and very high resolution (VHR) imagery. The buildings were first extracted using height from LiDAR data and normalized difference vegetation index (NDVI) from VHR image. A refinement step was then adopted to reduce the errors caused by shadow and spectral similarity between the buildings with color roofs and vegetated roofs and the trees. A post processing step was finally conducted to further improve the result. The proposed method was quantitatively evaluated and compared with existing method using airborne LiDAR data and Quickbird image. The results indicated that the proposed method significantly outperformed the existing method. The proposed method is applicable for building extraction using VHR image and LiDAR data over complex urban areas with tall buildings and buildings with color roofs or vegetated roofs.

Based on the target gasoline engine, a first-order with delay throttle-speed model is built from the step response experiment. Then the PID controller parameters are tuned by the internal model control (IMC) design methodology. Although simulation is good, experiment results are not ideal for multi-speed references. To enhance the speed regulator's robustness, the integral sliding mode control (ISMC) algorithm is presented. The bench test results show that ISMC can overcome the drawbacks of the PI control.

The knowledge exchanging and sharing in enterprise acts an important role in enterprise knowledge management, and the effective knowledge exchanging and sharing is an important guarantee of the enterprise knowledge application and knowledge innovation. Through the analyses on six factors that affect enterprise knowledge exchanging and sharing include the tacit degrees of knowledge itself, the ability of the knowledge sender and receiver, the similarity degree of the knowledge sender and receiver, knowledge exchanging means and knowledge exchanging environment, the effect evaluation systems of knowledge exchanging and sharing in enterprise are constructed and analyzed in this paper.