This paper reviewed the developments of the last ten years in the field of international high-resolution earth observation, and introduced the developmental status and plans for China's high-resolution earth obser...This paper reviewed the developments of the last ten years in the field of international high-resolution earth observation, and introduced the developmental status and plans for China's high-resolution earth observation program. In addition, this paper expounded the transformation mechanism and procedure from earth observation data to geospatial information and geographical knowledge, and examined the key scientific and technological issues, including earth observation networks, high-precision image positioning, image understanding, automatic spatial information extraction, and focus services. These analyses provide a new impetus for pushing the application of China's high-resolution earth observation system from a "quantity" to "quality" change, from China to the world, from providing products to providing online service.展开更多
传统扩张状态观测器(extended state observer,ESO)在运行时普遍存在着由于状态变量的初始观测值和实际值的偏差过大带来的初始微分峰值现象。为抑制微分峰值现象,避免系统调节过程中出现振荡,缩短调节时间,提高动态性能,提出了一种改...传统扩张状态观测器(extended state observer,ESO)在运行时普遍存在着由于状态变量的初始观测值和实际值的偏差过大带来的初始微分峰值现象。为抑制微分峰值现象,避免系统调节过程中出现振荡,缩短调节时间,提高动态性能,提出了一种改进型三阶时变参数ESO。首先,给出了改进型三阶时变参数ESO的构建方法和稳定性证明。然后,分析了该新型ESO在有扰动时的观测误差范围,并与传统ESO做了对比。最后,通过仿真表明该三阶改进型时变参数ESO能有效抑制微分峰值现象,且比传统的三阶非线性ESO具有更快的收敛速度和更高的观测精确度。展开更多
基金supported by National Basic Research Program of China(Grant No. 2012CB719906)
文摘This paper reviewed the developments of the last ten years in the field of international high-resolution earth observation, and introduced the developmental status and plans for China's high-resolution earth observation program. In addition, this paper expounded the transformation mechanism and procedure from earth observation data to geospatial information and geographical knowledge, and examined the key scientific and technological issues, including earth observation networks, high-precision image positioning, image understanding, automatic spatial information extraction, and focus services. These analyses provide a new impetus for pushing the application of China's high-resolution earth observation system from a "quantity" to "quality" change, from China to the world, from providing products to providing online service.
文摘传统扩张状态观测器(extended state observer,ESO)在运行时普遍存在着由于状态变量的初始观测值和实际值的偏差过大带来的初始微分峰值现象。为抑制微分峰值现象,避免系统调节过程中出现振荡,缩短调节时间,提高动态性能,提出了一种改进型三阶时变参数ESO。首先,给出了改进型三阶时变参数ESO的构建方法和稳定性证明。然后,分析了该新型ESO在有扰动时的观测误差范围,并与传统ESO做了对比。最后,通过仿真表明该三阶改进型时变参数ESO能有效抑制微分峰值现象,且比传统的三阶非线性ESO具有更快的收敛速度和更高的观测精确度。
