基于经验线性法的Hyperion高光谱图像地表反射率反演研究

Surface Reflectance Retrieval of Hyperion Hyperspectral Imagery Based on the Empirical Line Calibration Method

基于经验线性大气校正法，分别选择水体和水泥堤坝作为暗、亮目标，对目前唯一在轨运行的高光谱图像Hyperion进行大气校正。与表观反射率的比较说明大气作用与地物实际反射率大小有关；与实测光谱进行对比研究，表明经验线性法所得结果在近红外和短波红外区域精度较高，绝对误差小于10％，最小值为2．6％，而在可见光波段精度较低，绝对误差在10％～13％。在实际应用中，该方法的关键是合理选择校正目标场。

Sustainable municipal development is based on rational expansion of construction land. According data of land use during the last ten years, this paper analyses the current problem of construction land expansion, its causes, and puts forward potential solutions. It is showed that,even though protective policies on agricultural land have been escalated in recent years, several problems do exist in construction land use in Changsha City： erosion of agricultural land, inefficient usage, and deteriorated ecological function. The source of such irrational expansions during the past 10 years, which is revealed by economic analysis, is the fact that the externality generated by the expansion was not effectively settled. Based on this analysis, the government regulations should be given priority over market forces in future policy design is proposed.