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941.
分水岭变换在遥感影像线状特征提取中的应用 总被引:3,自引:0,他引:3
在现有目标识别方法的基础上 ,提出一种结合目标的特性进行分水岭变换提取目标的方法。试验结果表明 ,这种方法可以有效地从遥感影像中提取线状特征。 相似文献
942.
The seismic reflection studies carried in the Essaouira Basin, intermediate zone between the High Atlas and the Atlantic Margin, show the presence of halokinetic structures that played a significant role in the evolution of the basin. Salt dynamics was controlled by the Atlantic rifting and the Atlasic orogen. These tectonic controls and the margin segmentation are responsible for the diachronism of salt movement. Halokinesis varied in time and space in the basin and was more active offshore, where autochtonous and allochtonous salt layers are present. To cite this article: K. Mehdi et al., C. R. Geoscience 336 (2004). 相似文献
943.
In its current status, medical imaging involves a wide range of imaging modalities and is faced with a range of interesting research questions, while trying to automatically convert the huge floods of image data to useful information. The major characteristic of the developed techniques is the exploitation of visual similarities or differences; that is basically qualitative treatment of the information inherent in the images. This proves to be a major shortcoming, leading to erroneous or unreliable results in many cases. To this end, technology transfer from the part of photogrammetry can be proven very beneficial. Such a contribution can be geared by the fact that photogrammetry has developed efficient tools for accounting for imaging formation geometry. These tools, appropriately tuned for medical applications, can accelerate the technology transfer across the involved disciplines. Understanding the possible photogrammetric contributions by the medical imaging experts, and realizing the medical problems in photogrammetric terms by the photogrammetrists, remains a major barrier to this transfer. The intended scope of this paper is to provide a foundation for exchange of ideas and provoke photogrammetric research interest in these issues. 相似文献
944.
利用机载三维成像仪的DSM数据自动提取建筑物 总被引:6,自引:1,他引:6
利用三维成像仪获取的DSM作为数据源,首先采用影像分割得到建筑物的平面轮廓线,再根据建筑物一般具有规则平面形状的特点,对建筑物的平面边缘线进行规格化处理,最后求出建筑物的平均高度值,从面得到建筑物的三维信息。试验表明,该方法是实用的。 相似文献
945.
Preliminary analysis of the Knipovich Ridge segmentation: influence of focused magmatism and ridge obliquity on an ultraslow spreading system 总被引:2,自引:0,他引:2
Kyoko Okino Daniel CurewitzMiho Asada Kensaku TamakiPeter Vogt Kathleen Crane 《Earth and Planetary Science Letters》2002,202(2):275-288
Bathymetry, gravity and deep-tow sonar image data are used to define the segmentation of a 400 km long portion of the ultraslow-spreading Knipovich Ridge in the Norwegian-Greenland Sea, Northeast Atlantic Ocean. Discrete volcanic centers marked by large volcanic constructions and accompanying short wavelength mantle Bouguer anomaly (MBA) lows generally resemble those of the Gakkel Ridge and the easternmost Southwest Indian Ridge. These magmatically robust segment centers are regularly spaced about 85-100 km apart along the ridge, and are characterized by accumulated hummocky terrain, high relief, off-axis seamount chains and significant MBA lows. We suggest that these eruptive centers correspond to areas of enhanced magma flux, and that their spacing reflects the geometry of underlying mantle upwelling cells. The large-scale thermal structure of the mantle primarily controls discrete and focused magmatism, and the relatively wide spacing of these segments may reflect cool mantle beneath the ridge. Segment centers along the southern Knipovich Ridge are characterized by lower relief and smaller MBA anomalies than along the northern section of the ridge. This suggests that ridge obliquity is a secondary control on ridge construction on the Knipovich Ridge, as the obliquity changes from 35° to 49° from north to south, respectively, while spreading rate and axial depth remain approximately constant. The increased obliquity may contribute to decreased effective spreading rates, lower upwelling magma velocity and melt formation, and limited horizontal dike propagation near the surface. We also identify small, magmatically weaker segments with low relief, little or no MBA anomaly, and no off-axis expression. We suggest that these segments are either fed by lateral melt migration from adjacent magmatically stronger segments or represent smaller, discrete mantle upwelling centers with short-lived melt supply. 相似文献
946.
947.
多尺度分析技术广泛应用于高分辨率遥感影像的特征提取和建模。分解层数受制于影像的大小,下采样小波变换实现的影像多尺度表达难以描述大范围的空间模式,导致分类结果出现"胡椒盐"现象;面向对象的影像分析技术虽避免了"胡椒盐"现象,但由于仅利用了单尺度的的特征,也难以描述影像多层次的空间模式,导致分类精度较低。为改善分类结果中的"胡椒盐"现象和提高分类精度,提出了一种结合区域多尺度遥感影像分割和马尔可夫随机场的分类方法。首先,获得原始影像过分割区域,依据区域内亮度均值以及区域间的共享边界长度信息,提取影像低频和高频特征,采用该低频特征波段代替原始影像,重复分割与特征波段提取过程,形成影像的区域多尺度表达。然后,以原始图像为初始尺度,以分割区域为处理单元,以更细尺度分类结果为标记场先验,以当前高频特征建立特征场,逐层分类、投影,获得最终尺度分类结果。合成纹理影像和多光谱遥感影像的实验表明:相比于小波域多尺度建模方法和单尺度区域建模方法,本文提出的方法可以有效提高分类精度,并避免"胡椒盐"现象的产生。 相似文献
948.
ABSTRACT Urban functional zones (UFZs) are important for urban sustainability and urban planning and management, but UFZ maps are rarely available and up-to-date in developing countries due to frequent economic and human activities and rapid changes in UFZs. Current methods have focused on mapping UFZs in a small area with either remote sensing images or open social data, but large-scale UFZ mapping integrating these two types of data is still not be applied. In this study, a novel approach to mapping large-scale UFZs by integrating remote sensing images (RSIs) and open social data is proposed. First, a context-enabled image segmentation method is improved to generate UFZ units by incorporating road vectors. Second, the segmented UFZs are classified by coupling Latent Dirichlet Allocation (LDA) and Support Vector Machine (SVM). In the classification framework, physical features from RSIs and social attributes from POI (Point of Interest) data are integrated. A case study of Beijing was performed to evaluate the proposed method, and an overall accuracy of 85.9% was achieved. The experimental results demonstrate that the presented method can provide fine-grained UFZs, and the fusion strategy of RSIs and POI data can distinguish urban functions accurately. The proposed method appears to be promising and practical for large-scale UFZ mapping. 相似文献
949.
INTRoDUCTIoNTheclassificationofimagedataisoneofthemostimPOr-tantimagedataanalysistasksinremotesensing.Inpractice,theimageclassificationwillbedoneintwoways:per-fieldandper-pixelbasis(VenkateswarluandRaju,l993).Inper-fieldclassifiers,asmallhomogeneousregion(agroupofpix-eIsthatareneartoeachother)willbeclassifiedbyassumingsomedistributionforallthesepixels(VenkateswarluandRa-ju,1993).Inper-pixelclassification,eachpixelintheimagewillbeclassifiedintosomemeaningfultypeofgroundcover.Astherearelo… 相似文献
950.
纹理图像统计模型与纹理图像分割 总被引:4,自引:1,他引:4
本文详细介绍了一种新的纹理图像统计模型-Gibbs模型,给出了两种常用的Gibbs分布。在此基础上作者详细推导出了两种纹理图像的分割算法,并用一幅遥感图像进行了实验,获得了较好的分割结果。 相似文献