Resee矿山遥感监测系统变化向导模块在矿山变化信息提取中的应用

依靠自主研发的Resee矿山遥感自动监测系统中的变化向导模块可对矿区进行方法评价及变化图斑提取,辅助相关部门监视工作区存在的部分违规采矿行为,很好地实现对矿区采矿行为及影像的动态监测,对矿山环境的变化进行有效的监督管理,大大提高了矿山监测的效率和准确性.     

传感光纤-砂土界面力学性质的试验研究

近年来分布式光纤感测技术在岩土与地质工程领域的应用研究已成为一个研究热点,但工程实践表明,埋入式传感光纤与被测岩土体之间的变形协调性会对监测结果产生显著的影响,该问题一直制约着光纤感测技术在工程监测中的推广。本文通过一系列室内拉拔试验,对比了3种预埋于砂土中的单模光纤在不同上覆压力的作用下的拉拔力-拉拔位移曲线,并建立了一个用于描述光纤-砂土界面力学性质的三段式的拉拔模型,分析峰值拉拔力、残余拉拔力、有效拉拔位移和残余拉拔位移4个参数在不同上覆压力作用下的变化情况。分析结果揭示传感光纤-砂土界面的力学特性和应力传递规律,为分布式光纤传感技术在岩土体变形监测中的应用,尤其在变形监测光纤的选用标准方面,提供了参考依据。     

Remote sensing-based analysis of the planform changes in the Upper Amazon River over the period 1986–2006

An analysis of the planform changes of the Colombian reach of the Amazon River was carried out over a period of 19.9 years. Remote sensing image processing techniques were applied to Landsat images acquired in 1986, 1994, 2001 and, 2006. These images were selected based on minimal daily water level variations, while providing the widest temporal span. Plan view river changes and geomorphologic characteristics were examined to identify which channel pattern classification best represents this large tropical river system. Discharge was also analyzed to determine whether changes in the river's plan view are a direct response to variations in discharge. The system had a depositional tendency between 1986 and 2006, with a period where erosion was more intense than deposition between 1994 and 2001. Percent change in the plan view area of the system (1.4% yr⁻¹) and the maximum migration rates (125 m yr⁻¹) suggest that this reach of the Amazon is less active than reaches upstream and the downstream reach between the confluences of the Jutaí and Japurá Rivers. Variations in discharge appear to be responsible for deposition and erosion dynamics observed after this remote sensing analysis in the Colombian reach of the Amazon River. Characteristics including multiple channels with vegetated islands developed from within-channel deposition, meandering planform, lateral activity of channel margins, and the absence of islands with saucer-like morphology suggest a multichannel, meandering pattern for this reach of the Amazon, that corresponds to a laterally active anabranching river.     

基于ArcGIS镶嵌数据集的正射影像数据库构建方法初探

数字正射影像数据具有直观、信息量大、覆盖面广和经济、方便、获取快速等优点,是我国基础地理信息数据库的重要内容。本文讨论了基于ArcGIS镶嵌数据集栅格模型构建数字正射影像数据库的一些基本问题。首先对近年来的影像空间数据库技术进行了梳理,然后基于ArcGIS镶嵌数据集模型提出了数字正射影像数据库构建方法,其中对影像入库涉及的栅格数据存储模型、建库步骤、相关参数等问题进行了分析与探讨。最后,开展了海南省某测区小型正射影像数据库构建试验,通过试验证明了文中方法的可用性与可靠性。     

一种大文件多版本遥感影像数据组织管理方法

近年来,遥感技术的飞速发展使得影像数据的使用也越来越广泛和深入,而影像分辨率的增加,使得数据量急剧增长,对数据的存储和管理提出了很高的要求。针对传统遥感影像数据组织存储的不足,本文提出了一种大文件金字塔数据存储结构,用来高效存储管理影像数据;同时针对多时相遥感影像数据,提出了基于版本机制的影像数据管理模式。实验表明这种方法具有更高的存储检索效率。     

An ensemble pansharpening approach for finer-scale mapping of sugarcane with Landsat 8 imagery

We tested the effects of three fast pansharpening methods – Intensity-Hue-Saturation (IHS), Brovey Transform (BT), and Additive Wavelet Transform (AWT) – on sugarcane classification in a Landsat 8 image (bands 1–7), and proposed two ensemble pansharpening approaches (band stacking and band averaging) which combine the pixel-level information of multiple pansharpened images for classification. To test the proposed ensemble pansharpening approaches, we classified “sugarcane” and “other” land cover in the unsharpened Landsat multispectral image, the individual pansharpened images, and the band-stacked and band-averaged ensemble images using Support Vector Machines (SVM), and assessed the classification accuracy of each image. Of the individual pansharpened images, the AWT image achieved higher classification accuracy than the unsharpened image, while the IHS and BT images did not. The band-stacked ensemble images achieved higher classification accuracies than the unsharpened and individual pansharpened images, with the IHS-BT-AWT band-stacked image producing the most accurate classification result, followed by the IHS-BT band-stacked image. The ensemble images containing averaged pixel values from multiple pansharpened images achieved lower classification accuracies than the band-stacked ensemble images, but most still had higher accuracies than the unsharpened and individual pansharpened results. Our results indicate that ensemble pansharpening approaches have the potential to increase classification accuracy, at least for relatively simple classification tasks. Based on the results of the study, we recommend further investigation of ensemble pansharpening for image analysis (e.g. classification and regression tasks) in agricultural and non-agricultural environments.     

Quantifying uncertainty in remote sensing-based urban land-use mapping

Land-use/land-cover information constitutes an important component in the calibration of many urban growth models. Typically, the model building involves a process of historic calibration based on time series of land-use maps. Medium-resolution satellite imagery is an interesting source for obtaining data on land-use change, yet inferring information on the use of urbanised spaces from these images is a challenging task that is subject to different types of uncertainty. Quantifying and reducing the uncertainties in land-use mapping and land-use change model parameter assessment are therefore crucial to improve the reliability of urban growth models relying on these data. In this paper, a remote sensing-based land-use mapping approach is adopted, consisting of two stages: (i) estimating impervious surface cover at sub-pixel level through linear regression unmixing and (ii) inferring urban land use from urban form using metrics describing the spatial structure of the built-up area, together with address data. The focus lies on quantifying the uncertainty involved in this approach. Both stages of the land-use mapping process are subjected to Monte Carlo simulation to assess their relative contribution to and their combined impact on the uncertainty in the derived land-use maps. The robustness to uncertainty of the land-use mapping strategy is addressed by comparing the most likely land-use maps obtained from the simulation with the original land-use map, obtained without taking uncertainty into account. The approach was applied on the Brussels-Capital Region and the central part of the Flanders region (Belgium), covering the city of Antwerp, using a time series of SPOT data for 1996, 2005 and 2012. Although the most likely land-use map obtained from the simulation is very similar to the original land-use map – indicating absence of bias in the mapping process – it is shown that the errors related to the impervious surface sub-pixel fraction estimation have a strong impact on the land-use map's uncertainty. Hence, uncertainties observed in the derived land-use maps should be taken into account when using these maps as an input for modelling of urban growth.     

资源一号02C卫星多光谱数据真彩色模拟技术研究

资源一号02C卫星多光谱数据没有蓝色波段,给制作真彩色影像带来了一定困难。本文针对02C卫星多光谱波段的特点,分析了常用线性模拟蓝波段影像方法,选取多景不同时相的、覆盖山地或平地的真实数据进行加权法和平均值法的对比试验,定性与定量分析后的结果表明：基于加权法生成蓝波段的真彩色模拟结果,无论是从整体色调方面,还是从典型地类的颜色方面,均优于基于平均值法生成蓝波段的真彩色模拟结果,可进一步深入研究后进行规模化应用。     

基于定向片模型的SPOT-5遥感影像自检校光束法平差

本文通过建立内方位自检校模型,利用定向片模型对外方位元素进行内插建模,建立了基于定向片模型的自检校光束法平差,研究不同控制点数量和不同定向片间隔对定位精度的影响,并利用河南嵩山地区SPOT-5遥感影像数据对模型进行了实验验证和分析,结果表明,平面精度可以达到10.06m,高程精度可以达到8.84m.     

基于SmartImage的低空影像快速拼接应用案例分析

通过对低空数字航空摄影系统中的航摄数据使用SmartImage 软件进行影像数据拼接案例的介绍和分析,叙述了影像拼接的具体作业流程及特点。从数据操作的快速性和简便性上详细分析了其在应急测绘中的应用,为更好地利用无人机航摄数据做好快速应急测绘保障提供了技术思路。