从遥感图像监督分类结果到矢量对象的转换是遥感技术领域的一个瓶颈问题。提出了一种"分类图斑自适应概括"(Self-adaptive Generalization of Classified patch,SGCP)的方法,是针对这一问题的新尝试。SGCP能实现从破碎图斑到...从遥感图像监督分类结果到矢量对象的转换是遥感技术领域的一个瓶颈问题。提出了一种"分类图斑自适应概括"(Self-adaptive Generalization of Classified patch,SGCP)的方法,是针对这一问题的新尝试。SGCP能实现从破碎图斑到完整图像对象的自动转换,它由如下运算组成:(1)以形态学开启和形状系数分离道路与其他不透水表面;(2)以面积过滤和数学形态学操作去除噪声,以使图斑完整;(3)以递归凸残差回补简化图斑边界;(4)以膨胀和面积占优方法消除图斑裂隙;(5)以凸节点减少率评估图斑概括度,并同时以面积保持和分类精度保持评估概括精度;直至形成指定概括度的对象。概括运算的主要参数(如结构元素尺寸、递归次数、邻域窗口尺寸等)均由计算机自适应确定,同时预留部分用户调节参数,在自动概括的同时,允许人工干预概括程度。经Matlab仿真测试,该方法可以在保持分类精度与获取概括对象之间取得较好平衡。当图斑简化度上升22.9%时,面积平均变化仅为2.7%,分类精度仅平均下降0.72%。展开更多
Schottky diodes with an Ag/n-Si/W/Cu structure and 100μm in diameter were studied.Analyzing the silver metal surface coating on the n-Si substrate using a scanning probe microscopy（SPM） device showed a large number...Schottky diodes with an Ag/n-Si/W/Cu structure and 100μm in diameter were studied.Analyzing the silver metal surface coating on the n-Si substrate using a scanning probe microscopy（SPM） device showed a large number of nano patches in the surface with dimensions of 0 to 100 nm.The potential distribution of the patches revealed that the potential of each patch with the neighboring patches was different.The electrical characteristics of the devices were studied between temperature ranges of 300 and 380 K.When the temperature ideality factor approximately increases,the potential barrier height decreases.The potential barrier height was calculated separately from theⅠ-Ⅴand C-V characteristics.The main reasons for the significant difference between room temperature and higher temperatures were the differences in patch distribution,the different potentials of each patch,and the interactions between them.The effective potential barrier height depended on the degree of inhomogeneity,and thus the operating potential barrier height in the contact surface was smaller than the average value,and the ideality factor was more than unitary.With the increase in the potential value,the ideality factor becomes close to unitary, and with increasing temperatures,the ideality factor is increased.In this case,the maximum potential barrier height accrues at a greater distance from the metal contact.For this reason,at high temperatures the average value of the potential barrier height is smaller.Moreover,with increasing temperature,the ideality factor is increased.展开更多
Radiosity has been a popular method for photorealistic image generation.But the determination of form factors between curved patches is the most difficult and time consuming procedure, and also the errors caused by ap...Radiosity has been a popular method for photorealistic image generation.But the determination of form factors between curved patches is the most difficult and time consuming procedure, and also the errors caused by approximating source patch's radiosity with average values are obvious. In this paper,a radiosity algorithm for rendering curved surfaces represented by parameters is described. The contributed radiosity from differential areas on four vertices of the source patch to a receiving point is calculated firstly, then the contribution from the inner area of the source patch is evaluated by interpolating the values on four corners. Both the difficult problem of determining form-factors between curved surfaces and errors mentioned above have been avoided. Comparison of the experimental results using the new algorithm has been made with the ones obtained by traditional method. Some associated techniques such as the visibility test and the adaptive subdivision are also described.展开更多
文摘从遥感图像监督分类结果到矢量对象的转换是遥感技术领域的一个瓶颈问题。提出了一种"分类图斑自适应概括"(Self-adaptive Generalization of Classified patch,SGCP)的方法,是针对这一问题的新尝试。SGCP能实现从破碎图斑到完整图像对象的自动转换,它由如下运算组成:(1)以形态学开启和形状系数分离道路与其他不透水表面;(2)以面积过滤和数学形态学操作去除噪声,以使图斑完整;(3)以递归凸残差回补简化图斑边界;(4)以膨胀和面积占优方法消除图斑裂隙;(5)以凸节点减少率评估图斑概括度,并同时以面积保持和分类精度保持评估概括精度;直至形成指定概括度的对象。概括运算的主要参数(如结构元素尺寸、递归次数、邻域窗口尺寸等)均由计算机自适应确定,同时预留部分用户调节参数,在自动概括的同时,允许人工干预概括程度。经Matlab仿真测试,该方法可以在保持分类精度与获取概括对象之间取得较好平衡。当图斑简化度上升22.9%时,面积平均变化仅为2.7%,分类精度仅平均下降0.72%。
文摘Schottky diodes with an Ag/n-Si/W/Cu structure and 100μm in diameter were studied.Analyzing the silver metal surface coating on the n-Si substrate using a scanning probe microscopy（SPM） device showed a large number of nano patches in the surface with dimensions of 0 to 100 nm.The potential distribution of the patches revealed that the potential of each patch with the neighboring patches was different.The electrical characteristics of the devices were studied between temperature ranges of 300 and 380 K.When the temperature ideality factor approximately increases,the potential barrier height decreases.The potential barrier height was calculated separately from theⅠ-Ⅴand C-V characteristics.The main reasons for the significant difference between room temperature and higher temperatures were the differences in patch distribution,the different potentials of each patch,and the interactions between them.The effective potential barrier height depended on the degree of inhomogeneity,and thus the operating potential barrier height in the contact surface was smaller than the average value,and the ideality factor was more than unitary.With the increase in the potential value,the ideality factor becomes close to unitary, and with increasing temperatures,the ideality factor is increased.In this case,the maximum potential barrier height accrues at a greater distance from the metal contact.For this reason,at high temperatures the average value of the potential barrier height is smaller.Moreover,with increasing temperature,the ideality factor is increased.
文摘Radiosity has been a popular method for photorealistic image generation.But the determination of form factors between curved patches is the most difficult and time consuming procedure, and also the errors caused by approximating source patch's radiosity with average values are obvious. In this paper,a radiosity algorithm for rendering curved surfaces represented by parameters is described. The contributed radiosity from differential areas on four vertices of the source patch to a receiving point is calculated firstly, then the contribution from the inner area of the source patch is evaluated by interpolating the values on four corners. Both the difficult problem of determining form-factors between curved surfaces and errors mentioned above have been avoided. Comparison of the experimental results using the new algorithm has been made with the ones obtained by traditional method. Some associated techniques such as the visibility test and the adaptive subdivision are also described.
