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以“像方观测直线与像方预测直线必须重合”作为几何约束条件,以有理函数模型（RFM）作为高分辨率卫星影像的几何处理模型,提出了一种直线特征约束的高分辨率卫星影像区域网平差方法.本文方法仅需像方直线与物方直线相对应,无须像方直线上的像点与物方直线上的地面点一一对应.通过对圣迭戈试验区的两景IKONOS 影像、斯波坎试验区的两景QuickBird 影像和普罗旺斯试验区的两景SPOTG5影像进行试验,结果表明：本文方法可以充分利用直线特征作为控制条件,有效补偿RPC参数中的系统误差,获得的IKONOS、QuickBird和SPOT-5影像区域网平差的平面与高程精度均优于1个像素.

<正>异源高分辨率卫星影像匹配是高分辨率卫星影像处理的技术关键,也是实现三维重建、信息提取、变化监测等应用研究工作的技术基础。研究表明在地面覆盖相同的情况下,随着空间分辨率的提高,卫星影像数据量急剧增加,并由此产生了几何噪声增大、阴影变化影响、局部形变加剧、纹理相似性降低等异源高分辨率影像特有的问题。传统同(异)源遥感影像匹配方法多数着眼于低、

高精度定位是遥感影像几何处理和地理空间信息获取的基础,是利用高分辨率卫星遥感影像测制各种比例尺地形图的基本保障。论文针对当前高分辨率卫星遥感影像几何处理中还存在的问题,在深入分析高分辨率卫星遥感影像成像机理的基础上,引入四元数作为描述成像传感器姿态的数学工具,对基于四元数的高分辨率卫星遥感影像定位理论与方法所涉及的外方位元素建模、成像几何模型的构建、多传感器的区域网平差等多个关键问题进行了较为深入的研究，论文完成的主要工作和创新点如下：

通过对高分辨率卫星遥感影像成像机理进行分析，提出一种基于四元数微分方程的外方位元素求解方法。该方法采用四元数描述影像成像姿态，建立基于四元数微分方程的成像几何模型。为求解该模型，引入3个独立的解算参数，计算过程中不直接求解姿态四元数，而是解算参数，使得未知数个数与现有方法相同，并采用Tikhonov正则化理论进一步求解方程。试验结果表明该方法正确可靠，具有很好的稳定性和适应性，解算参数的引入效果显著，对定位精度有一定的提高，并且完全避免了三角函数运算。

简要介绍高分辨率卫星遥感影像的严格几何处理模型，提出较为严密的影像姿态角系统误差检校模型。通过对SPOT-5、CBERS-02B两种卫星遥感影像的试验证实模型的正确性和方法的有效性。对影像姿态角系统误差进行补偿后，可明显提高卫星遥感影像对地目标定位的精度，且优于影像姿态角常差检校的效果，目标点平面定位精度达到了±（2-～3）像素的水平。

针对高分辨率遥感影像有理函数模型（RFM）在实际应用中存在过度参数化和定位精度不高的问题，提出基于离差阵和消去变换及残余系统误差补偿的高分辨率遥感影像RFM优化方法。试验结果表明，经过参数筛选后的RFM参数均为无偏估计值，拟合精度可以达到全部参数用于拟合时的精度，而且模型病态性基本消除，模型稳定性更高。残余系统误差补偿方法可以有效消除RFM拟合严格成像模型的残余误差，达到与严格成像模型一致的对地定位精度。

Coarse-resolution satellite albedo products are important for climate change and energy balance research because of their capability to characterize the spatiotemporal patterns of land surface parameters at both the regional and global scales. The accuracy of coarse-resolution products is usually assessed via comparison with in situ measurements. The key issue in the comparison of remote sensing observations with in situ measurements is scaling and uncertainty. This paper presents a strategy for validating 1-km-resolution remote sensing albedo products using field measurements and high-resolution re- mote sensing observations. Field measurements were collected to calibrate the high-resolution （30 m） albedo products derived from HJ-1a/b images. Then, the calibrated high-resolution albedo maps were resampled （i.e., upscaled） to assess the accuracy of the coarse-resolution albedo products. The samples of field measurements and high-resolution pixels are based on an uncertainty analysis. Two types of coarse-resolution albedo datasets, from global land surface satellite （GLASS） and moderate-resolution imaging spectroradiometer （MODIS）, are validated over the middle reaches of the Heihe River in Chi- na. The results indicate that the upscaled HJ （Huan Jing means environment in Chinese and this refers to a satellite constel- lation designed for environment and disaster monitoring by China） albedo, which was calibrated using field measurements, can provide accurate reference values for validating coarse-resolution satellite albedo products. However, the uncertainties in the upscaled HJ albedo should be estimated, and pixels with large uncertainties should be excluded from the validation process.

The alpine treeline ecotone is an important component of mountain ecosystems of the Nepal Himalaya; it plays a vital role in the livelihood of indigenous people,and provides ecosystem services. However,the region faces a problem of paucity of data on treeline characteristics at the regional and landscape scales. Therefore,we used Remote Sensing（RS）,and Geographic Information Science（GIS） approaches to investigate cross-scale interactions in the treeline ecotone. Additionally,European Space Agency land cover map,International Center for Integrated Mountain Development（ICIMOD） land cover map,ecological map of Nepal,and United States Geological Survey Shuttle Radar Topography Mission-Digital Elevation Model were used to analyze treeline pattern at the regional scale. Digital Globe high-resolution satellite imagery of Barun（eastern Nepal） and Manang（central Nepal） were used to study treeline patterns at the landscape scale. Treeline elevation ranges from 3300-4300 m above sea level. Abies spectabilis,Betula utilis,and Pinus wallichiana are the main treeline-forming species in the Nepal Himalaya. There is an east to west treeline elevationgradient at the regional scale. No slope exposure is observed at the regional scale; however,at the landscape scale,slope exposure is present only in a disturbed area（Manang）. Topography and human disturbance are the main treeline controlling factor in Barun and Manang respectively.

Both interchannel wetlands and multi-channels are crucial geomorphologic units in an anastomosing river system. Planform characteristics and development of interchannel wetlands and multi-channels control the characteristics of anastomosing rivers. To under- stand the role that interchannel wetlands play in the development of anastomosing rivers, a study was conducted on the Maqu Reach of the Upper Yellow River （MRUYR）, a gravel-bed anastomosing river characterized by highly developed interchannel wetlands and ana- branches. Geomorphologic units in the studied reach were extracted from high resolution satellite imagery in Google Earth. The size distributions of interchannel wetlands and inter- channel wetland clusters （IWCs）, a special combination of interchannel wetlands and ana- branches, were investigated. Geomorphologic parameters, including the ratio of interchannel wetland area to IWC area （P）, shoreline density （DL）, and node density （Dn） were used to analyze planform characteristics of IWCs and the development of multi-channels in the stud- ied reach. The results suggest that small or middle sized interchannel wetlands and large or mega sized IWCs are more common at the study site. The area of IWC （Su） is highly cor- related with other geomorphologic parameters. P increases with increasing Su, and the upper limit is about 80%, which indicates that the development of interchannel wetlands and ana- branches in the IWC is in the equilibrium stage. In contrast, D~ and D, show a tendency to decrease with increasing Su due to diverse evolution processes in IWCs with different sizes. There are three main reasons leading to the formation of IWCs： varying stream power due to the meandering principal channel; development of the river corridor due to the weakening of geologic structure control; and high stability of interchannel wetlands due to conservation by shoreline vegetation.

In this paper, an attempt to analyse landslide hazard and vulnerability in the municipality of Pahuatlfin, Puebla, Mexico, is presented. In order to estimate landslide hazard, the susceptibility, magnitude （area-velocity ratio） and landslide frequency of the area of interest were produced based on information derived from a geomorphological landslide inventory; the latter was generated by using very high resolution satellite stereo pairs along with information derived from other sources （Google Earth, aerial photographs and historical information）. Estimations of landslide susceptibility were determined by combining four statistical techniques： （i） logistic regression, （ii） quadratic discriminant analysis, （iii） linear discriminant analysis, and （iv） neuronal networks. A Digital Elevation Model （DEM） of lo m spatial resolution was used to extract the slope angle, aspect, curvature, elevation and relief. These factors, in addition to land cover, lithology anddistance to faults, were used as explanatory variables for the susceptibility models. Additionally, a Poisson model was used to estimate landslide temporal frequency, at the same time as landslide magnitude was obtained by using the relationship between landslide area and the velocity of movements. Then, due to the complexity of evaluating it, vulnerability of population was analysed by applying the Spatial Approach to Vulnerability Assessment （SAVE） model which considered levels of exposure, sensitivity and lack of resilience. Results were expressed on maps on which different spatial patterns of levels of landslide hazard and vulnerability were found for the inhabited areas. It is noteworthy that the lack of optimal methodologies to estimate and quantify vulnerability is more notorious than that of hazard assessments. Consequently, levels of uncertainty linked to landslide risk assessment remain a challenge to be addressed.