长江三峡库区Landsat7 ETM+数据的处理方法探讨

Landsat7 ETM+是陆地卫星系列的最新数据,其突出优势在于提高了多光谱波段的空间分辨率,增加了一个分辨率为15 m的全色波段,丰富了数据的信息量。选取长江三峡库区的两景ETM+原始数据,基于不同的地学遥感应用要求,试验性地研究了Landsat7 ETM+新型数据的数字处理方法,并比较了这些处理方法的应用效果。结果表明,选择适当的数字方法对新型Landsat7ETM+遥感数据进行处理,能够快速、有效地获得同时具备较高的光谱分辨率和空间分辨率的遥感数字图像,显示出较好的应用优势。     

包抽样对异常检测的影响及其消除方法研究

针对当前流统计抽样在异常检测中存在的问题,分析包抽样和时域聚合导致流记录时间序列失真的原因,利用网络异常的尺度聚集特性,提出一种基于不重叠窗口聚合的多尺度分解方法,以消除由包抽样和时域聚合带来的信号噪声。仿真结果表明,该方法能降低抽样率对流尺度上信噪比的影响,提高异常检测的性能。     

ETM影像融合的评价分析

针对Landsat-7 ETM影像，对采用HIS变换、Brovey变换、相关系数加权法、SFIM变换、ISVR变换5种方法实现的ETM全色波段与ETM多光谱波段融合结果进行分析，并以均值、标准差、信息熵、平均梯度及相对偏差作为评价指标，通过试验对融合影像进行综合定量评价。结果表明，HIS变换光谱失真最大；Brovey变换在光谱保真和保持空间分辨率方面都不理想；相关系数加权法的融合结果严重地依赖权系数的取值；基于SFIM变换的融合方法，能最大限度地保留光谱特征，但空间分辨率提高不明显；而基于ISVR变换的融合方法，光谱失真小，空间分辨率高，其最大优势是考虑了多光谱影像与全色影像间的波段关系，可作为ETM影像融合的最佳方法。
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美国陆地卫星7号宽带数据

美国陆地卫星７ 号已于１９９９ 年４ 月１５ 日发射升空,预计７ 月中旬左右将由测试、调整阶段进入正常运行阶段,届时,国际地面站将可按协议接收其下行的宽带数据。对宽带数据结构的全面了解是进行遥感图像预处理系统开发的基础,介绍了美国陆地卫星７ 号宽带数据的基本结构,供相关研究人员参考     

基于卡尔曼滤波的Landsat-8卫星影像几何精校正

卡尔曼滤波是一种递推线性最小方差估计算法,被广泛应用于GPS动态数据处理、组合导航和通信与信号处理等领域。本文将卡尔曼滤波引入卫星影像几何精校正处理中,以Landsat-8卫星影像为例,利用卡尔曼滤波方法和地面控制点构建运动方程和测量方程,实现了对卫星星历和姿态数据的修正。实验证明,相比于传统最小二乘平差法,该方法使用较少的控制点即可达到稳定的精度,降低了几何精校正对控制点数量的依赖,具有较高适用性。     

Mapping land cover change in a reindeer herding area of the Russian Arctic using Landsat TM and ETM+ imagery and indigenous knowledge

Much of Russia north of the treeline is grazed by reindeer, and this grazing has materially altered the vegetation cover in many places. Monitoring vegetation change in these remote but ecologically sensitive regions is an important task for which satellite remote sensing is well suited. Further difficulties are imposed by the highly dynamic nature of arctic phenology, and by the difficulty of obtaining accurate official data on land cover in arctic Russia even where such data exist. We have approached the problem in a novel fashion by combining a conventional multispectral analysis of satellite imagery with data on current and historical land use gathered by the techniques of social anthropology, using a study site in the Nenets Autonomous Okrug (NAO). A Landsat-7 ETM+ image from the year 2000 was used to generate a current land cover classification. A Landsat-5 TM image was used to generate a land-cover classification for 1988, taking due account of phenological differences and between the two dates. A cautious comparison of these two classifications, again taking account of possible effects of phenological differences, shows that much of the study area has already undergone a notable transformation to grass-dominated tundra, almost certainly as a result of heavy grazing by reindeer. The grazing pattern is quite heterogeneous, and may have reached unsustainable levels in some areas. Finally, we suggest that this situation is unlikely to be unique to our study area and may well be widespread throughout the Eurasian tundra zone, particularly in the west.     

ADSL的故障分析与处理方法

随着通信和计算机技术的飞速发展,非对称数字用户环路（ADSL）技术得到了更加广泛的应用。但是随着ADSL用户的迅猛增加,ADSL的故障频繁发生,用户故障申诉率也有大幅度的提高。文章简要介绍了ADSL的基本原理及其发展历程,着重分析了一线工作人员在实际中经常遇到的问题,对故障的处理方法进行了讨论,详细阐明了造成网速缓慢的多重原因。     

基于ETM+的深圳市绿地信息提取方法研究

针对深圳市生态绿地信息系统的规划需求,利用Landsat ETM+影像通过对3种图像增强方法(原始波段组合、差值运算、NDVI与其它波段组合)进行比较,集中探讨了深圳市绿地信息提取的最佳方法。结果表明,NDVI与其它波段组合法对于深圳市绿地信息的提取,可以得到比较理想的绿地分布信息,达到了城市生态绿地监测的要求。     

Retrieval of Component Temperatures based on Landsat-7 ETM+ Remote Sensing Data

Land surface temperature plays an important role in drought monitoring and Simulation of surface heat flux.In arid and semi\|arid regions,the Two\|Source Energy Balance model (TSEB) is commonly used to calculate the heat flux of the earth’s surface.Taking the typical irrigated area of the middle reaches of Heihe as the research area,the four Landsat\|7 ETM+ remote sensing images are selected.The soil surface temperature and canopy temperature were retrieved by combining vegetation index with TSEB model.The decomposition algorithm of soil surface temperature and vegetation canopy temperature is mainly discussed.The results showed that soil surface temperature and vegetation canopy temperature had good temporal and spatial consistency.The inversion accuracy of soil surface temperature and vegetation canopy temperature is indirectly verified by surface net radiation and surface heat flux.The calculated values of surface net radiation and surface heat flux correlate well with the observed values,and the correlation coefficient is greater than 0.92.The linear regression analysis of surface net radiation and surface heat flux shows that the fitting accuracy is high.The soil surface temperature and canopy temperature obtained by surface temperature decomposition are feasible for monitoring drought in typical areas and simulating surface heat flux.     

基于Excel与XML交互的物流业数据处理方法

XML数据文件具有的与平台无关、可移植性强等特性使其已成为跨系统交换数据的标准格式,而Excel的强大数据统计分析功能使其广泛应用在财务、统计、金融等领域。Excel与XML数据交互处理功能可以实现物流业动态数据交换、分析与处理。     

基于Excel与XML交互的物流业数据处理方法

XML数据文件具有的与平台无关、可移植性强等特性使其已成为跨系统交换数据的标准格式，而Excel的强大数据统计分析功能使其广泛应用在财务、统计、金融等领域。Excel与XML数据交互处理功能可以实现物流业动态数据交换、分析与处理。