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高分辨率遥感在城市发展动态监测中的应用 总被引:3,自引:1,他引:3
与传统的遥感影像相比,高分辨率遥感影像有着空间分辨率高、时间分辨率高、信息量大、所包含的地物的几何和纹理信息更加明显、能提取地物三维信息等优点。城市中的研究对象多属于一些尺寸相对较小且空间信息较为重要的地物,再加上已形成一套全新的面向对象的高分辨率遥感数据的处理和信息提取方法。这使得高分辨率遥感技术成为城市发展动态监测以及相关信息提取的最有效手段。动态监测中获得的数据还进一步运用于城市规划布局、市容市政管理、城市生态环境保护、城市交通建设规划、城市防震减灾以及数字交通和数字城市的建设等诸多方面。 相似文献
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M. R. Deinert J. -Y. Parlange T. Steenhuis J. Throop K. Ünlü K. B. Cady 《Journal of Hydrology》2004,290(3-4):192-201
Few methods exist for measuring rapidly changing fluid contents at the pore scale that simultaneously allow whole flow field visualization. We present a method for using real-time neutron radiography to measure rapidly changing moisture profiles in porous media. The imaging technique monitors the attenuation of a thermal neutron beam as it traverses a flow field and provides measurements every 30 ms with an image area >410 cm2 and a spatial resolution 0.05 cm. The technique is illustrated by measuring the variation in moisture content across a wetting front moving at constant velocity through SiO2 sand. The relative contributions of the hydraulic conductivity and diffusivity terms in Richards' equation to the total fluid flux within the wetting front region were also measured. The diffusivity was found to rise from zero to a peak value within the wetting front region before falling off while the conductivity was found to rise monotonically. The reliability of the technique was checked via mass balance. 相似文献
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机载SAR图像定向参数的F.LDT解法 总被引:1,自引:1,他引:1
从SAR图像的F.Leberl构像模型出发,推导了成像载体匀速运动条件下的SAR图像定向参数的直接变找(Direct Transformation for F.Leberl Model。F.LDT)解法。通过比较F.LDT解法与F.Leberl构像方程线性代迭代解法的实验结果,得出结论:F.LDT解法可以满足精度要求,且无需初值,不需迭代,计算过程简单,避免了线性化迭代方法不收敛的情况。最后对影响F.LDT解法精度的因素进行了分析。 相似文献
718.
美国国立光学天文台的IRAF软件系统,已成为国内光谱处理的主要计算机软件之一。由射电天文需要发展起来的FITS格式,已作为国际上交换磁带数据资料的通用格式。本文简单地介绍了FITS格式,讨论了如何将厚片CCD光谱观测资料转换为IRAF图像,继而转换为标准FITS格式。这对于使用IRAF系统进行光谱处理,以及国内国际间的资料交换是有用的。 相似文献
719.
Determination of the cleat angle distribution of the RECOPOL coal seams, using CT-scans and image analysis on drilling cuttings and coal blocks 总被引:1,自引:1,他引:0
Karl-Heinz A.A. Wolf Frank van Bergen Rudy Ephraim Henk Pagnier 《International Journal of Coal Geology》2008,73(3-4):259-272
Cleat orientation, cleat frequency and cleat angle distribution of deep coal seams are only available by the use of drilling cores and from coal mine samples. Coal drilling cuttings are a cheap and fast alternative to measure cleat angle distributions with the use of image analysis techniques. In this study oriented coal samples and drilling cuttings of the RECOPOL field experiment are compared and used to explain and validate the proposed method. In other words, cleat angle distributions from drilling cuttings are measured by image analysis. The geological framework of the polish coals is described. The image analysis methodologies for the measurement of fracture faces of cuttings and from CT-scan images, derived from these coals, are explained. The results of the methods on the cuttings are compared with cleat orientation distributions from CT-scans and artificial fragments from coal blocks of the same seams. These evaluations show high agreements between the methods. The cleat angle distributions of drilling cuttings of four seams are compared with the cleat orientation distributions of a regional structural geological study. The high correlation in this study shows that cleat angle distributions of coal seams can be used as input parameters for reservoir modelling. 相似文献
720.
We have used Ramaty High Energy Solar Spectroscopic Imager (RHESSI) modulation profiles in the 25 – 300 keV range to construct
high-fidelity visibilities of 25 flares having at least two components. These hard X-ray visibilities, which are mathematically
identical to the visibilities of radio imaging, were input to software developed for mapping solar flares in the microwave
domain using the Maximum Entropy Method (MEM). We compared and contrasted the MEM maps with Clean and Pixon maps made with
RHESSI software. In particular, we assessed the reliability of the maps and their morphologies for future investigations of
the symmetry of bipolar electron beaming in the sample set. 相似文献