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581.
基于碱熔法的改进和多接收电感耦合等离子质谱仪(MC-ICP-MS)的发展,近年来高精度Si同位素组成(δ30Si)分析方法取得了长足进步,分析精度(2SD)自气体质谱仪(GS-MS)时代的±0.15‰~±0.30‰ 提高到优于±0.10‰,足以辨析高温过程中Si同位素发生的微小分馏,并且避免了实验流程中使用含氟等危险化学品。二次离子质谱(SIMS)和飞秒激光剥蚀(fs LA)的发展使得原位Si同位素组成分析精度近期也优化到±0.10‰~±0.22‰。文章对近年来Si同位素分析方法的发展沿革进行综述,探讨建立溶液法MC-ICP-MS的高精度Si同位素分析方法的进展与局限,并比对了国内外各个实验室已发表国际国内Si同位素标准物质测定值,最后总结了硅酸盐地球(BSE)、地壳和陨石等主要地质储库的δ30Si组成范围。  相似文献   
582.
稀少控制的多源卫星影像区域网平差研究   总被引:1,自引:0,他引:1  
利用多源卫星影像的联合区域平差技术,在控制点极少和影像纹理特征极差的情况下,实现更大覆盖范围的更高精度快速定位,具有重要的实际意义.本文研究了少控制弱连接的多卫星影像区域网平差的精度问题,利用P5和WorldView-I卫星影像,进行了缺少控制点和连接点的困难地区联合区域网定位实验,分析了不同情况下区域网平差对系统误差的改正效果.研究成果对测绘困难地区的工作有一定的参考意义.  相似文献   
583.
This paper is an exploratory study, which aimed to discover the synergies of data fusion and image segmentation in the context of EO-based rapid mapping workflows. Our approach pillared on the geographic object-based image analysis (GEOBIA) focusing on multiscale, internally-displaced persons’ (IDP) camp information extraction from very high spatial resolution (VHSR) images. We applied twelve pansharpening algorithms to two subsets of a GeoEye-1 image scene that was taken over a former war-induced ephemeral settlement in Sri Lanka. A multidimensional assessment was employed to benchmark pansharpening algorithms with respect to their spectral and spatial fidelity. The multiresolution segmentation (MRS) algorithm of the eCognition Developer software served as the key algorithm in the segmentation process. The first study site was used for comparing segmentation results produced from the twelve fused products at a series of scale, shape, and compactness settings of the MRS algorithm. The segmentation quality and optimum parameter settings of the MRS algorithm were estimated by using empirical discrepancy measures. Non-parametric statistical tests were used to compare the quality of image object candidates, which were derived from the twelve pansharpened products. A wall-to-wall classification was performed based on a support vector machine (SVM) classifier to classify image objects candidates of the fused images. The second site simulated a more realistic crisis information extraction scenario where the domain expertise is crucial in segmentation and classification. We compared segmentation and classification results of the original images (non-fused) and twelve fused images to understand the efficacy of data fusion. We have shown that the GEOBIA has the ability to create meaningful image objects during the segmentation process by compensating the fused image’s spectral distortions with the high-frequency information content that has been injected during fusion. Our findings further questioned the necessity of the data fusion step in rapid mapping context. Bypassing time-intensive data fusion helps to actuate EO-based rapid mapping workflows. We, however, emphasize the fact that data fusion is not limited to VHSR image data but expands over many different combinations of multi-date, multi-sensor EO-data. Thus, further research is needed to understand the synergies of data fusion and image segmentation with respect to multi-date, multi-sensor fusion scenarios and extrapolate our findings to other remote sensing application domains beyond EO-based crisis information retrieval.  相似文献   
584.
针对侧扫声纳受海洋复杂环境影响大的特点,本文提出了一种基于相邻条带共视目标的方法,并结合声纳原始记录文件中航向、姿态等信息,对侧扫声纳位置及航向等进行修正,实现了相邻条带拼接,对拼接后的图像分别采用加权平均和小波变换的方法进行融合处理,并使用信息熵对图像质量进行了评价.试验验证了该方法的有效性和可行性.  相似文献   
585.
南极是地球上对全球气候变化最敏感、响应最迅速的区域之一,针对南极冰盖变化的监测对很多领域有着十分重要的意义。本文针对南极区域选取MODIS与Land—sat ETM+两种遥感影像,通过ENVI遥感平台,利用包括WAVELET变换法、PCA变换法、BROVEY变换法和HPF变换法等4种影像方法进行融合,并选择均值、标准差、偏差指数、相关系数等评价指标,对融合后的影像进行评价。得出结论:ETM+影像WAVELET算法融合效果最好,而对于Modis影像PCA算法融合效果最好,两种卫星影像对不同尺度的监测都有着各自的优势。  相似文献   
586.
殷涛  张姝娟  李德江 《东北测绘》2014,(6):122-124,130
对影像融合基本方法进行了综述,并采用基于HSV,PC和Brovey算法对资源三号影像进行融合试验。在已有融合试验及结果评定的基础上,将该方法广泛应用于地理国情普查中的多源遥感影像处理,为后续的业内分类及信息提取提供有利支撑。  相似文献   
587.
王昆  张丽  王志勇  田丰 《测绘科学》2013,38(3):140-142,92
基于空间变异理论,本文提出了一种基于半方差函数的STARFM改进模型。该模型利用半方差函数分析基准Landsat影像的空间统计特性,确定影像各波段的空间相关距离——变程,然后将变程的2倍作为STARFM模型滑动窗口的宽度,预测了指定MDOIS时刻的Landsat影像;改变滑动窗口大小后的预测影像和实际观测影像各波段的平均绝对差值和平均差值均大于利用半方差函数确定滑动窗口宽度的预测影像,表明STARFM改进模型具有优越性。  相似文献   
588.
This paper presents a data fusion method in distributed multi-sensor system including GPS and INS sensors' data processing. First, a residual \Gc2-strategy with the corresponding algorithm is designed. Then a coefficient matrices calculation method of the information sharing principle is derived. Finally, the federated Kalman filter is used to combine these independent, parallel, real-time data. A pseudolite (PL) simulation example is given.  相似文献   
589.
This paper studies urban waterlog-draining decision support system based on the 4D data fusion technique. 4D data includes DEM, DOQ, DLG and DRG. It supplies entire databases for waterlog forcast and analysis together with non-spatial fundamental database. Data composition and reasoning are two key steps of 4D data fusion. Finally, this paper gives a real case: Ezhou Waterlog-Draining Decision Support System (EWDSS), with two application models, i. e., DEM application model, water generating and draining model.  相似文献   
590.
On the basis of a thorough understanding of the physical characteristics of remote sensing image, this paper employs the theories of wavelet transform and signal sampling to develop a new image fusion algorithm. The algorithm has been successfully applied to the image fusion of SPOT PAN and TM of Guangdong province, China. The experimental results show that a perfect image fusion can be built up by using the image analytical solution and re-construction in the image frequency domain based on the physical characteristics of the image formation. The method has demonstrated that the results of the image fusion do not change spectral characteristics of the original image.  相似文献   
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