In China, the urban-rural dual structure of land market has resulted in urban sprawl caused by industrial diffusion. Urban sprawl disintegrated agricultural communities in suburbs, thereby increasing the unemployment ...In China, the urban-rural dual structure of land market has resulted in urban sprawl caused by industrial diffusion. Urban sprawl disintegrated agricultural communities in suburbs, thereby increasing the unemployment rate among farmers who lost their lands. To address this problem, the Chinese government proposed a reform program to analyze the monopoly of the government in the land market and guarantee the property rights of farmers. This study analyzed the connection between land market mechanism and suburban space formation. Results concluded that the current land transfer system caused industrial urban sprawl, and the reform program may promote the urban sprawl of population. Two typical models of rural land development were studied. A model called land cooperatives based on land pooling joint stock system was proposed to build a compact and sustainable suburban space.展开更多
Under the premise of unchanging the collective ownership and the mode of family business, China should choose land shares pack system as the goal pattern of farmland system innovation. It is hoped that the pattern is ...Under the premise of unchanging the collective ownership and the mode of family business, China should choose land shares pack system as the goal pattern of farmland system innovation. It is hoped that the pattern is accepted and supported by both sides of the government and the farmers, and then it constructs the land reasonable circulation and the effective centralism mechanism, thus realizing smooth transition from the traditional agriculture to the modem agriculture.展开更多
The research of unmanned aerial vehicles＇（UAVs＇）autonomy navigation and landing guidance with computer vision has important signifcance.However,because of the image blurring,the position of the cooperative points ...The research of unmanned aerial vehicles＇（UAVs＇）autonomy navigation and landing guidance with computer vision has important signifcance.However,because of the image blurring,the position of the cooperative points cannot be obtained accurately,and the pose estimation algorithms based on the feature points have low precision.In this research,the pose estimation algorithm of UAV is proposed based on feature lines of the cooperative object for autonomous landing.This method uses the actual shape of the cooperative-target on ground and the principle of vanishing line.Roll angle is calculated from the vanishing line.Yaw angle is calculated from the location of the target in the image.Finally,the remaining extrinsic parameters are calculated by the coordinates transformation.Experimental results show that the pose estimation algorithm based on line feature has a higher precision and is more reliable than the pose estimation algorithm based on points feature.Moreover,the error of the algorithm we proposed is small enough when the UAV is near to the landing strip,and it can meet the basic requirements of UAV＇s autonomous landing.展开更多
文摘In China, the urban-rural dual structure of land market has resulted in urban sprawl caused by industrial diffusion. Urban sprawl disintegrated agricultural communities in suburbs, thereby increasing the unemployment rate among farmers who lost their lands. To address this problem, the Chinese government proposed a reform program to analyze the monopoly of the government in the land market and guarantee the property rights of farmers. This study analyzed the connection between land market mechanism and suburban space formation. Results concluded that the current land transfer system caused industrial urban sprawl, and the reform program may promote the urban sprawl of population. Two typical models of rural land development were studied. A model called land cooperatives based on land pooling joint stock system was proposed to build a compact and sustainable suburban space.
文摘Under the premise of unchanging the collective ownership and the mode of family business, China should choose land shares pack system as the goal pattern of farmland system innovation. It is hoped that the pattern is accepted and supported by both sides of the government and the farmers, and then it constructs the land reasonable circulation and the effective centralism mechanism, thus realizing smooth transition from the traditional agriculture to the modem agriculture.
基金supported by the NUAA Fundamental Research Funds(No.NS2013034)
文摘The research of unmanned aerial vehicles＇（UAVs＇）autonomy navigation and landing guidance with computer vision has important signifcance.However,because of the image blurring,the position of the cooperative points cannot be obtained accurately,and the pose estimation algorithms based on the feature points have low precision.In this research,the pose estimation algorithm of UAV is proposed based on feature lines of the cooperative object for autonomous landing.This method uses the actual shape of the cooperative-target on ground and the principle of vanishing line.Roll angle is calculated from the vanishing line.Yaw angle is calculated from the location of the target in the image.Finally,the remaining extrinsic parameters are calculated by the coordinates transformation.Experimental results show that the pose estimation algorithm based on line feature has a higher precision and is more reliable than the pose estimation algorithm based on points feature.Moreover,the error of the algorithm we proposed is small enough when the UAV is near to the landing strip,and it can meet the basic requirements of UAV＇s autonomous landing.
