高分辨遥感综合定标技术系统的研发助推我国遥感产业进入发展新阶段

随着定量遥感信息技术的快速发展,对遥感数据质量检测与评估提出了迫切的应用需求。本研究攻克了宽动态高均匀固定人工靶标技术、自主辐射定标技术、高分辨率微波图像分辨率在轨检测技术等瓶颈问题,构建了涵盖地面标准测试目标系统、地面测量技术系统、测试数据处理系统在内的高分辨遥感综合定标技术系统,建成了国际上系统化程度最高、综合测试功能最强、适用范围最广的航空航天共用高分辨遥感综合定标场。该技术系统已用于多型国产新型遥感载荷的严格航空校飞以及多个系列国内外高分辨率遥感卫星的在轨定标与性能评测,在提升我国遥感技术社会经济效益转化质量和回报效率等方面发挥了重要作用。

FY-3C MERSI反射波段在轨宽动态综合辐射定标方法

为解决FY-3C/MERSI反射波段非线性响应导致传统两点定标不适用问题,提出了在轨宽动态综合辐射定标方法。融合多种不依赖于地面同步测量的替代方案,利用各方案定标样本的多等级反射率特性,实现遥感器宽动态范围的辐射定标。每种方案的定标样本采用分段平均方法进行等权重融合,最终定标系数基于融合后样本通过加权拟合回归获得。非线性特征采用发射前室外定标实验分析的二次项系数进行修正,在轨计算定标斜率和截距。分析和验证结果表明:各替代方案样本分布具有很好一致性,融合样本相关性可达0.99;综合定标结果在反射率大于10%的中高端目标回归残差小于1%,高端定标结果与基于深对流云目标的交叉定标(DCC)检验样本的相对差异小于1.5%,敦煌同步观测实验检验结果表明中端精度优于3%;由于MERSI对低亮度辐射响应能力显著降低,发射前室外定标实验获得的非线性系数不能适用,定标结果在低目标反射率出现高估现象。该成果可应用于所有FY-3C/MERSI反射通道,明显降低两点法定标的不确定性以及非线性的影响。

Preliminary study on road-region ecosystem stability evaluation

A scientific and rational evaluation on road-region ecosystem stability is the premise to properly deal with the relationship between highway constructing and ecological environment protecting to a sustainable development. Based on the connotative meaning and the procedure of evaluation on road-region ecosystem stability, this paper studied the principles and the method on determining the evaluation index system on road-region ecosystem stability. It put forward an index system for assessing road-region ecosystem stability as a reference. On the basis of detailed analyze of the multidimensional space of road-region ecosystem, a new multi-objective comprehensive evaluation method for road-region ecosystem stability is presented and a calculation tormula for multi-objective comprehensive level of road-region ecosystem stability. This method was used to evaluate road-region ecosystem stability of Lin-Chang highway. This method possessed definite theoretical value and reliability in practice.